CN1241148A

CN1241148A - Method for dewatering microalgae with bubble column

Info

Publication number: CN1241148A
Application number: CN 97180839
Authority: CN
Inventors: S·A·格尔彻尔; J·S·卡内尔
Original assignee: Eastman Chemical Co
Current assignee: Eastman Chemical Co
Priority date: 1996-12-20
Filing date: 1997-12-10
Publication date: 2000-01-12

Abstract

A process for dewatering an aqueous suspension of microalgae is disclosed in which the aqueous suspension of the algae is introduced into a bubble column or a modified bubble column for generating a froth of bubbles and adsorbed algal cells that can be separated from the aqueous suspension. In one advantageous embodiment, the bubble column is a multi-stage loop-flow flotation column that has three loop-flow zones, each of which is defined by a draft tube concentrically mounted in the column to divide each loop-flow zone into a riser and the downcomer. Fine bubbles of gas and brine are in cocurrent upward flow in the riser and in cocurrent downward flow the downcomer. A higher gas holdup is promoted in the riser than in the downcomer, thereby circulating the brine in loop-flow upwardly through the riser and downwardly through the downcomer. Liquid communication between adjacent loop-flow zones is substantially eliminated. A froth enriched in algae is generated that can be separated from the aqueous suspension. The process has application in the recovery of mixed carotenoids from Dunaliella salina.

Description

Carry out the method for dewatering microalgae with bubble column

Invention field

The present invention relates to the method for extracting substance from algae.More specifically, the present invention relates to from Dunaliella salina, extract the method for mixing carotenoid.

Background of invention

Carotenoid is in citrus and yellow vegetable and the dark orange-yellow pigment of finding in multiple deep green food.β-Hu Luobusu is the abundantest in the various types of carotene.β-Hu Luobusu can change into vitamin A in vivo.Vitamin A is a kind of fat-soluble VITAMIN, and is different with the water-soluble vitamins that can not store in vivo, and it can mainly be stored for some time in liver in vivo.If the vitamin A of overdose is then harmful.But β-Hu Luobusu changes into vitamin A in vivo as required, is generally considered to be the source of nontoxic vitamin A, even is taking in a large number down.

β-Hu Luobusu has been proved to be a kind of antioxidant, can resist the harm that oxidation brings takes place in the animal tissues.For above-mentioned reasons and as the source of nontoxic vitamin A, β-Hu Luobusu is a high value, and is commercially important nutritional additive.But people pay close attention to such problem recently: β-Hu Luobusu is widespread in nature, and how it is separated from mix carotenoid, as a kind of nutritional additive with health role.

Derive from the mixing carotenoid of plant, comprise β-Hu Luobusu, can from various sources, obtain, comprise Radix Dauci Sativae, spinach and plam oil, but they are higher in relative concentration that Dunaliella salina belongs in the algae.These algaes are grown in the spissated salts solution usually.Under suitable growing condition, mix carotenoid and account for more than 10% of algae dry weight.

For example, when Dunaliella salina was in the salt brine solution that high temperature, high light and sodium chloride concentration be higher than 20% (weight/unit volume), it trended towards accumulating a large amount of carotenoid and glycerine.It is believed that carotenoid can protect algae to avoid illumination.Along with the increase of salt concn in the salt solution, the concentration of carotenoid also increases, till the limit salt concn that algae can tolerate.

Proposed at present much from Dunaliella salina, to extract the method for β-Hu Luobusu, carotenoid and other valuable ingredients.Dunaliella salina provides the source of a kind of β-Hu Luobusu and other carotenoid, and it has been used to the production of several nutritional additives at present.But, under the situation of the solvent that does not adopt genotoxic potential and other undesirable substance, from Dunaliella salina, extract carotenoid cost-effectively and still have some problems.Also there are a lot of difficulties as a kind of carotenoid source in Dunaliella salina in the coml exploitation.

The salt tolerant algae comprises Dunaliella salina, generally is grown in the salt lake, for example the Great Salt lake of Utah.From lake and other natural surroundings, collect Dunaliella salina commercial be generally unpractical, partly cause is, when the growth conditions of algae was not added control, its concentration was very low.

Commercial, collect in the culture that Dunaliella salina is grown from the pond of special building out of doors usually.Generally all build in hot dry, the overcast and rainy few area of weather in these outdoor ponds, helps improving the output of carotenoid.

There is the method for two kinds of different aquatic breed to cultivate algae.A kind of is intensive, and another kind is extensive.These two kinds of aquatic cultural techniques all need to add feed in culture environment, to replenish necessary inorganic nutriment, as phosphorus, nitrogen, iron and trace-metal, these all are necessary by photosynthesis increase biomass.

The main difference of these two kinds of production models is: the hybrid mode difference of algae growing environment.Intensive pond adopts machine tool to mix, and extensive pond utilizes wind-force to mix.Therefore, in the aquatic breed of intensity, can be controlled more accurately the factor that influences the algae growth.

In two kinds of intensive and extensive patterns, the saltiness of growing environment is controlled in certain scope, is about 18%-27% (weight sodium chloride/unit volume salt solution) usually.This concentration range is believed to obtain maximum carotenoid output.The optimum growh scope that it has been generally acknowledged that Dunaliella salina is between saltiness 18%-21%, and when saltiness surpasses approximately 27% the time, the carotenoid in the algae biomass has production peak.It is reported, when saltiness reaches about 24% the time, the output maximum of carotenoid in the per unit volume salt solution.

The general investment in the outdoor pond of intensive aquatic breed is bigger, adopts concrete constructions usually and tiles with plastics.The brinish degree of depth is controlled at 20 centimetres usually, and this is the optimum depth that produces the algae biomass.The pond profile of the intensive aquatic breed that has proposed has multiple.But out of door water guide pond generally is commercial most important.The water guide pond has adopted impeller to mix.Need careful control chemistry and biology parameter, comprise concentration, salt solution pH value and the culture purity of salt and feed.

Extensive aquatic breed is carried out in Australian sweltering heat and arid area.The outdoor pond of extensive aquatic breed is usually greater than the outdoor pond of the aquatic breed of intensity, and they are built on the riverbed usually.Open-air pond generally surrounds with earth embankment.Do not adopt mixing equipment.The mixing in pond is undertaken by wind-force.In order to obtain maximum carotenoid output, need make the pond degree of depth and chemical constitution realize optimization.

But, compare with intensive pond, because it is bigger that extensive pond lacks the volume in effectively mixing and pond, the parameter of carotenoid output that it is best and culture purity and stability is more wayward, the brinish change of component is bigger, and the concentration of the biomass of algae also is lower than intensive pond.Extensive pond more is subject to the influence of predator and rival's invasion and attack.

Predator and rival generally can not survive in the salt concn more than 20% or 20%.If the pond salt concn is lower than about 20%, culture may be subjected to the predator's of breeding invasion and attack rapidly, thereby kills the Dunaliella salina population in a large number.Main predator is ciliate Fabreasalina and boiled shrimps with shell in salt water Artemia salina.When salt concn is lower than approximately 15% the time, other algae easily competes nutrition with Dunaliella salina, and the predator also will further reduce the Dunaliella salina population.

Because culture is more rare, from the salt solution of extensive pond, collects algae than from intensive pond, collecting algae and have more problem.But, have now found that algae is tending towards assembling in heaps at the edge in extensive pond and natural salt lake.Algae is often blown over the surface in lake or pond, in side gathering in heaps (windrows) with the wind.Now think,, can significantly improve economic benefit if having the ability of piling up algae of gathering because the high density of algae is assembled.Yet the method for algae is piled up in also dissatisfied at present gathering.

Gather consistently from the gather position of algae of a fixed that to pile up algae normally impossible.The direction of wind has certain unpredictability usually, and often changes.Algae heap perhaps along the pond or the edge, lake form in different positions.When the algae heap does not have to process with the poor dilute suspension of algae when fixed is gathered position formation, will cause output to descend.Because the input of the culture of processing dilution will increase, the cost of gathering also improves thereupon.

Yet, height gather cost can be by the aquatic cultivating pool of building dense type the time concrete and the fund input of plastics offset.The extensive pond of per unit volumetrical soil system building cost is starkly lower than builds the cost that the aquatic cultivating pool of concrete intensity is arranged.

Now think,, can imagine the cost that to save the pond building basically, the cost and the configuration brinish cost of feed so if can from the lake of its spontaneous growth, gather algae.But the algae of gathering from lake and other natural surroundings is generally considered to be uneconomic, does not also have commercial benefits.Common also salt concn, the mineral substance of lake water and the degree of mixing in trophic component and natural salt lake of uncontrollable lake water.The algae culture of the dilution of poor stability also may occur.

Partly also have many problems and difficulty owing to separate algae from the salt solution of their growths, the processing of the poor culture of Dunaliella salina is normally uneconomic.Algae has mobility and density is moderate, be the elliptical shape of about 12-16 * 25 micron size, and these make the algaes of gathering have certain difficulty.

Dunaliella salina is generally by using chemical floc or setting accelerator and settling vessel, whizzer, strainer, sorbent material or other separation means to separate from the salt solution that contains algae.Chemical processing agent as silane, can be used for strengthening in the adsorption medium absorption.There has been several different methods from algae, to extract β-Hu Luobusu, carotenoid and other valuable ingredients, comprised glycerine and protein.Varsol, edible oil solvent and supercritical co all have been suggested as the extraction solvent.Algae also can carry out fragmentation by mechanical means, is beneficial to the extraction of composition.

The use of chemical additive such as flocculation agent and setting accelerator has limited the business development of Dunaliella salina as carotenoid and β-Hu Luobusu source, and partly cause is that these materials join algae suspension, has increased cost in especially rare suspension.And chemical additive chemical processing agent and varsol are considered to undesirable components in nutritional additive.

The Dunaliella salina of gathering more cost-effectively, and extract carotenoid and other valuable ingredients, and make it contain less or do not contain bad additive, be very necessary.

Summary of the invention

The invention provides and a kind ofly from the micro algae growth substratum, separate little algae, so that from this little algae, extract the method for composition.This method comprises can be with algae dehydration and the absorption bubble separation method that obtains algae enriched material (therefrom can extract economically and can extract composition).Extractible enriched material can just obtain the enriched material from various.Polluting the chemical additive and the treatment agent of growth medium or algae enriched material can avoid using.If desired, growth medium after the extraction and algae residue also can return its growing environment.

The present invention can make the algae dehydration that obtains economically from the dilute suspension in natural lake and pond.Cell content in dilute suspension is lower than 2000 cells/ml growth mediums sometimes.Many absorption bubble separating units can be used for making the algae dehydration.In corresponding absorption bubble separating step, algae can concentrate gradually.

The present invention can be applicable to algae and piles up gathering of thing, and comprises a kind of equipment of movably gathering.On the one hand, absorption bubble separation method uses air-flow froth flotation equipment that make with light plastic, that the area that contacts to earth is little.Area is little owing to contact to earth, and equipment can be installed in and be easy to move on flat-bed trailer, trailer, raft or other easy-to-handle transportation means of piling up thing formation position.This equipment can be moved to piles up the thing position, rather than waits for that piling up thing moves to the equipment position.

The present invention also can make the more spissated suspension dehydration of cultivating economically in extensive and intensive cultivating pool, wherein the quantity of the cell in this pond can reach 1,000,000 cells/ml growth mediums sometimes.

Method of the present invention comprises following step: at first, the source that obtains the algae suspension in growth medium can comprise intensive pond, extensive pond or natural lake, as Great Salt lake's salt solution of the Utah of Dunaliella salina riotous growth.After algae suspension obtains, from water-containing medium, separate algae by absorption bubble partition method.

On the other hand, the present invention includes dispersed gas flotation body method (generally include machinery with the foam flotation method of air-flow), gas dissolved flotation process and electrolysis process, these methods are used for making algae suspension dehydration that Dunaliella salina belongs to and extract composition from algae not using under adverse chemical additive or the treatment agent condition.The use of food grade solvent can make the rate of recovery of mixing carotenoid in the Dunaliella salina improve.

Electrolysis and gas dissolved flotation are different from the dispersed gas flotation body.When water-containing medium was strong brine, because salt solution electroconductibility is better than clear water, stronger electric current was essential for the electrolytic floatage technology.Gas dissolves than more being not easy in clear water in strong brine usually.

The dehydration of Dunaliella salina can be surrounded the cytolemma of frond by breaking, and removes moisture by absorption foam method method then under the situation of not using setting accelerator or flocculation agent and carries out.Though do not wish to accept the limitation of opinion, can think that when surrounding the membranolysis of frond, frond is adsorbed on the hydrophobic bubble that closely contacts with salt solution.The use of shear conditions can make cotton-shaped frond fracture usually, and for the method for direct flotation flock, this condition is inadvisable.Algae appears to contain enough concentration and can produce the natural tensio-active agent of stable foam.There are several fracture methods to discuss in the detailed Description Of The Invention hereinafter.

In the pneumatic flotation of one of dispersed gas flotation body method, gas is dispersed into rill.Gas can be air, or oxygen-free gas or do not contain the gas of the oxygenant that makes the carotenoid oxidation.Rill closely contacts with algae suspension, and the absorption algae forms foam and agglomerate of algae and the salt solution that does not contain algae in the foamy surface.Foam separates with spissated algae suspension form of foam from liquid phase with the agglomerate of algae.

If desired, flotation aid can be used for strengthening the rate of recovery.At least in the Dunaliella salina dehydration in salt solution, can not need flocculation agent or setting accelerator, but need, also can use.The disruptive algae by being adsorbed in bubble by flotation, rather than by coagulating the wadding process.High shear field can be used for the bubble that provides little, and can make between foam and particulate and closely contact, but in the method for floating of wadding a quilt with cotton with fixed attention, generally uses low shear field, to reduce the flock fracture to minimum.

By producing algae suspension liquid jet, make liquid jet pass through gas again, the gas dispersion phase in the algae suspension of going forward side by side, like this, the gas that is used for pneumatic flotation can be dispersed into rill.In the detailed Description Of The Invention be a kind ofly can be applied to this equipment in content on the one hand of the present invention hereinafter with the Jameson groove of describing.

As in tower, enter in the liquid phase by jet flow stream, gas can be dispersed into rill.A kind of multi-stage circulating-flow flotation tower is sometimes referred to as " MSTLFLO " tower, is a kind of equipment that is used to implement this partial content of the present invention.

By importing gas in algae suspension, mechanical shearing suspension and gas again, gas can be dispersed into rill.By importing gas in turbulent, swiftly flowing liquid, gas can be dispersed into rill, comprises the fixedly agitator that produces rill in this liquid.Usually, liquid is clear water, salt solution or a kind of surfactivity solution.

According to environment and obtainable equipment situation, aforesaid device and other can produce rill and can provide the combination between the tight equipment that contacts between foam and the algae suspension also to be suitable for.

Foam can be finished by following several method with tight contact the between the algae suspension.Foam can mix by machinery or air-flow with suspension.Rotary blade on the mechanical mixing equipment general using Z-axis provides mechanically mixing and ventilation.Ventilate and also can be undertaken by gas blower.

It is to rely on gas to join in the biphasic system of bubble and algae suspension that air-flow mixes, and forms density variation and realizes mixing.Between foam and the algae suspension can by convection current or and the combination of stream or the whole bag of tricks contact.

Absorption bubble separating step is recycled and reused for usually and concentrates algae suspension, can obtain the algae enriched material from algae suspension, and is suitable for extracting extractible composition from algae, comprises extracting from Dunaliella salina and mixes carotenoid.

In another aspect of this invention, method of the present invention comprises filters algae suspension.Algae suspension can with contact or filter by filter membrane (as microfiltration).By the thick-layer filter media, before absorption bubble separating step, carry out usually, be a kind of pre-concentration step.Though any disruption method of describing in the detailed description of the present invention hereinafter is desirable, algae suspension is through enough pressure drops usually, and algae is generally just broken before filtering.Micro-filtration is usually as a kind of back enrichment step, and it carries out after absorption bubble separating step, to obtain a kind of algae enriched material that high density gas is extracted the algae composition that is suitable for.

On the other hand, the present invention includes the algae suspension that to have dewatered and contact, and from the algae suspension of dehydration, extract composition with suitable solvent.If desired, solvent can be pre-dispersed in the algae suspension that extracts subsequently.In the invention process, the extraction solvent that is suitable for using comprises: edible oil, flavouring agent, petroleum chemistry solvent and high density gas, however may not obtain identical result.Flavouring agent is considered to safe usually, has excellent characteristic as extracting solvent, and its viscosity is low, be easy to use, have stronger dissolving power than edible oil.The petroleum chemistry solvent is not used in the extraction of nutritional additive composition usually, for this reason, is often avoided using.

If the suitable concn of algae obtains in the suspension, if desired, extraction can be finished by high density gas, and high density gas comprises overcritical and subcritical carbonic acid gas and other gas.Generally, after pneumatic flotation, algae is concentrated by microfiltration membrane, to obtain to be suitable for carrying out the concentration of the residue of composition extraction with high density gas.But, if desired, be with or without microfiltration step, can use more traditional extracting method.

Like this, compare with the existing Dunaliella salina method of extract mixing carotenoid with dewatering and from algae of gathering, the present invention especially provide more economical effectively and the qualified method of nutrition.Can be from rare enriched material, pile up thing or the more spissated source and gather.If desired, can use the equipment of movably gathering.Under the condition of not using flocculation agent, setting accelerator or other bad additive, can finish dehydration by absorption bubble separation method.β-Hu Luobusu and other carotenoid can use food grade solvent to extract from spissated algae, to obtain edible mixing carotenoid.

The accompanying drawing summary

Features more of the present invention and advantage are described.In conjunction with the accompanying drawings, other advantage of the present invention will become obvious along with the description of invention process.Wherein:

Fig. 1 is acquisition, the algae dehydration of algae suspension and the schema that extracts composition from algae.

Fig. 2 is the pump circulation sketch of frond of breaking.

Fig. 3 is the cross-stream micro-filtration general flow chart of algae suspension.

Fig. 4 is circulation and a time relation synoptic diagram in the cross-flow microfiltration flow process of Fig. 3.

Fig. 5 is for describing the sketch of different zones in the foam flotation method.

Fig. 6 is the pneumatic flotation general flow chart, comprises the rougher, the selected pond that make algae suspension dehydration, scans the pond.

Fig. 7 is the sketch of mechanical foam flotation cell.

Fig. 8 is the sketch of single downspout conductor Jameson groove.

Fig. 9 is multi-stage circulating-flow foam flotation tower (being also referred to as a MSTLFLO tower) sketch.

Figure 10 is Canadian tower (being also referred to as a foam column or conventional tower sometimes) sketch.

Figure 11 is favourable pneumatic flotation general flow chart, comprises Jameson rougher, one-level Jameson cleaner cell, secondary MSTLFLO preparator, cross-flow microfiltration unit, continuous high density gas extraction unit and the cyclonic separator that mixes the carotenoid product is provided.

Figure 12 extracts the method flow diagram that mixes carotenoid and other valuable components from algae.

Detailed Description Of The Invention

The general step that separates algae from the algae growth medium of the present invention as shown in Figure 1. Fig. 1 has represented to mix carotenoid for extracting from Dunaliella salina, makes to contain the method that algae is the salt solution dehydration of Dunaliella salina.

Dunaliella salina is some uniqueness in various algaes, and it is generally and contains chlorophyllous unicellular organism, does not have real cell membrane. Yet Dunaliella salina is considered to have the protectiveness phospholipid cell membrane, and this cell membrane is broken in the invention process. In the separation process of absorption bubble, influential to the surface-active effect of Dunaliella salina in salt solution mainly is composition in the algae body, rather than cell membrane.

Should be realized that, comprise Dunaliella bardawil kind in the Dunaliella, as described herein-in the same, content of the present invention is applicable to Dunaliella bardawil too. Perhaps have some disputes in the document about the Dunaliella classification, Dunaliella salina (Dunaliella salina) is that same kind also is possible with Dunaliella bardawil.

But, should be realized that to also have other algae, fresh water and salt algae also can be adopted method of the present invention to dewater, but not necessarily be obtained identical result. Perhaps, other algae comprises other beneficiating ingredient, comprises carotenoid, protein and other organic compound, if necessary, also can extract according to the present invention, but not necessarily obtain identical result. Content of the present invention also is applicable to the algae of Chlorophyta and Rhodophyta usually.

For ease of reading, following title has been listed the remaining content and the embodiment of detailed Description Of The Invention.I. algae II. algae cell rupture III. chemical assistant and chemical processing agent (optional, but optional usually) the IV. mechanical filter of gathering carries out the algae dehydration to separate algae V. absorption bubble partition method from growth medium

A. general introduction

B. pneumatic flotation

C. pneumatic flotation flow process

1. roughly select

2. selected

3. scan

D. common machinery and air-flow flotation cell

1. mechanical flotation cell

2. air-flow flotation cell

The a.Jameson groove

B. multi-stage circulating-flow flotation tower (MSTLFLO)

The c.Canadian tower

D. gas-sparged hydrocyclone (ASH)

E.EKOFLOT air-flow flotation cell

F.Microcel ^TMThe microfoam flotation tower

G. other floatation equipment

E. favourable pneumatic flotation flow process VI. reclaims composition from spissated algae suspension

A. the purifying of composition with separate

B. β-Hu Luobusu and other carotenoid

C. product and application

D. glycerine, protein and other composition VII. embodiment

A. cell rupture in pump circulation

B. thick-layer filters

C. microfiltration

D. pneumatic flotation

1. mechanical foam flotation

2. air-flow pneumatic flotation

The a.Jameson groove

B. multi-stage circulating-flow flotation tower (MSTLFLO)

The c.Canadian tower

D. gas-sparged hydrocyclone (ASH)

E. the recovery of valuable components

1. solvent distribution coefficient

2. liquid extraction

3. liquid extraction mass transfer kinetics

4. extracting carotenoid I. algae continuously with Limonene gathers

Among Fig. 1,, obtain containing the feedstream of Dunaliella salina salt aqeous suspension from its source according to step 20.Usually from the source algae suspension pump is delivered to the algae dehydration equipment, just obtained feedstream.Generally, impeller pump is used to the algae of gathering, however the also alternative use of other pump.Carry out all kinds liquid when shifting in chemical industry, impeller pump is one of the most widely used pump.

Sometimes, adopt the pump of movably gathering algae suspension to be transferred to dehydration equipment from the source.In this case, the present invention can be used for piling up gathering of thing.The pump of gathering can be floating pump or submersible pump, or can be installed in the pump on raft or the miscellaneous equipment, and this equipment is easy to move to the position of piling up thing formation.

Dewatering of the present invention mainly relies on the little foam flotation tower of the area that contacts to earth to carry out.Area is little owing to contact to earth, and on the flat-bed trailer that equipment can be installed in, trailer, raft or other easy-to-handle transportation means, this transportation means is easy to move to or the approaching position that receives feedstream.This equipment can be moved to the position of gathering, rather than waits for that the position of gathering moves to the equipment position.

The concentration that is used as the algae suspension of feedstream can change to more spissated suspension scope at dilute suspension.The present invention can dewater the algae dilute suspension in natural lake and the pond.For example, the present invention can be used for making the natural Dunaliella salina population dilute suspension dehydration that obtains from the Great Salt lake, Utah.

Cell concn in the dilute suspension is lower than 2000 cells/ml growth mediums sometimes.Pile up the position that thing forms because the removable pump of gathering can be moved to, the use that this moves the pump of gathering has improved the economic benefit that obtains algae suspension.

The present invention can make the extensive and intensive more spissated suspension dehydration that obtains in the pond of cultivating economically, and its cell quantity can reach 1,000,000 cells/ml growth mediums sometimes.II. algae cell rupture

Shown in Fig. 1 step 22, usually, no matter filter by the separation of absorption bubble or by thick-layer, the Dunaliella salina frustule all breaks before the suspension dehydration.The disruptive cell has the high rate of recovery, mixes carotenoid/milliliter suspension at 0.0003 milligram and mixes between carotenoid/milliliter suspension with 0.3 milligram.It is about 2 that this scope is equivalent to, 000-3,000,000 frustule/milliliter.

The process of ruptured cell can be carried out in air, but is favourable under the condition of oxygen-free gas or oxygenant, and the composition that can reduce ruptured cell is exposed in the oxygen.The oxidation of valuable compound comprises that the oxidation of carotenoid then can be avoided basically.Suitable gas comprises the algae cellular constituent is inert gasses, as nitrogen, carbonic acid gas, argon gas be considered to chemically inert rare gas of tool and their mixture other.

Ruptured cell is necessary for reclaiming carotenoid before the air-flow pneumatic flotation.But, should be appreciated that the air-flow floatation equipment when operation, also will make cell rupture, as will be explained hereinafter, so the step of independent ruptured cell in advance is unnecessary.In the shear field that the rotor of mechanical foam floatation equipment and stator structure form, cell is easy to break.By complete cell is joined in the mechanical foam floatation equipment, can the reclaiming more than 95% of effective cell.If before or after the sepn process of absorption bubble, use thick-layer filtering and concentrating algae suspension, the process of ruptured cell is necessary, because thick-layer can be caught frond effectively.

Any suitable method all can be used for ruptured cell.Cell can break mechanically, as high-shear impeller and French squeezing machine.By making the valve of suspension flow in recycle pump, also can make cell rupture.

The first step of dehydration is under high pressure to make algae suspension by the Jameson groove, and this moment, the algae cell also can be broken.The process of Jameson groove and its ruptured cell will pneumatic flotation technology hereinafter carries out describing in the content of algae suspension dehydration.By the algae of in the Jameson groove, breaking, can save the independent step of breaking.

Come the recovery part feedstream by the pump of gathering that salt solution is transported to dehydration equipment from its source, can make suspension be easy in the blowback road, circulate.

The equipment of the algae cell that breaks shown in Figure 2 is by making the valve of suspension flow in the blowback road come ruptured cell.Fig. 2 will describe among the embodiment hereinafter, when also having described simultaneously in the pump circulation ruptured cell, is how to determine the pressure drop and the rate of recovery.

As shown in Figure 2, by pump 38 (can be impeller pump), algae suspension be transported to dehydration equipment 36 from its source 34.Pump main road 40 carries salt solution to dehydration equipment.Throttling valve 42 in the pump main road is used to adjust pressure drop.Salt solution advances dehydration equipment by material inlet pipeline 44.Circulating line 46 is used for carrying salt solution from pumping oral-lateral to pumping into the oral-lateral circulation.By the valve in the blowback road 50, the flow velocity in the circulating line can change as required to reach required recovery percent.

The algae suspension flow when cell rupture is carried out in a pressure drop, there is the quantity of two parameter decision ruptured cells.First parameter is the size of pressure drop, and second parameter is the cell quantity of this pressure drop of flowing through.The per-cent of algae of breaking improves with the raising of pressure drop and recovery percent.Be lower than under about 200 pounds/square inch pressure drop condition, repeating repeatedly can to make cell rupture more than 40% by pressure drop.Yet, when recovery percent is higher than 100%, be higher than under about 150 pounds of/square inch pressure drop conditions, it is little to produce effects.Repeat repeatedly can increase the percentage of ruptured cell by pressure drop.

Confirm, algae suspension is passed through by the about 100-300% of the rate of recovery, the pressure drop that the blowback road of the about 50-200 pound of pressure drop/square inch provides, Dunaliella salina can effectively break.In addition, confirmed that also the about 100-150 pound/pressure drop of square inch and the rate of recovery of about 200-300% are suitable for.III. chemical assistant and chemical processing agent (optional, but optional usually)

Because a variety of causes that describes below especially obtains the reason of product as nutritional additive from algae, use chemical assistant and chemical processing agent normally to there is no need when algae is gathered and dewater.Should be emphasized that in implementation process of the present invention, chemical assistant and chemical processing agent are normally unwanted.In other and ruptured cell technology associated viscera of the present invention, also can not use chemical assistant and chemical processing agent to dewater.But, if desired, can select to use chemical assistant and chemical processing agent.

According to the needs of various purposes, before the dehydration chemical assistant is joined in the algae suspension.The chemical assistant that improves separating effect can be divided into three types: setting accelerator, surface-modifying agent and pre-dispersed solvent.Before extraction step, as before suspension dehydrating step, the solvent that uses in the following continuous extraction step that reclaims carotenoid can disperse in algae suspension.These solvents it is said by " pre-dispersed ".Solvent comprises pre-dispersed solvent, will describe in the extraction step of the present invention hereinafter.The interpolation of setting accelerator such as ion setting accelerator and polymer flocculation agent can produce the bigger separated aggregate that is easy to.The interpolation of surface-modifying agent such as pore forming material and collector makes algae be more conducive to flotation.

Chemical assistant can join in the mixing equipment behind cell rupture or before the separation of absorption bubble.But, do not need to use undesirable chemical assistant when carrying out the Dunaliella salina dehydration among the present invention.The cell rupture technology can be so that the algae dehydration among the present invention.

Opposite chemical assistant can influence the quality and the value of the nutritional additive for preparing with the algae composition unfriendly, also influences the quality of algae growing environment simultaneously unfriendly.Perhaps, some chemical assistants in the process of preparation nutritional additive are harmful to health.For algae growing environment and algae residue, the use of chemical assistant also can cause the problem in the offal treatment.For example, when the algae suspension that obtains from the Great Salt lake dewatered, owing to do not use bad chemical assistant, salt solution can return in the lake.

From economic angle, some chemical assistants also are worthless.When relative rarer suspension was used to collect algae in natural lake and the extensive pond, the frond that condenses need use a large amount of chemical substances, as alum.Therefore, need the subsequent step of separation chemistry additive from frond, the also corresponding production cost that increased.

Though chemical assistant is normally unnecessary, use pore forming material to be still feasible with the rate of recovery that improves algae in the pneumatic flotation process.Pore forming material can join before entering froth flotation equipment in gas phase or the liquid phase, or directly joins in the algae suspension in the froth flotation equipment, to increase foamy stability and to produce rill.The example of pore forming material comprises: 2-Ethylhexyl Alcohol, methyl isobutyl carbinol (being also referred to as MIBC) and Dowfroth 250.Dowfroth 250 can be from being positioned at Midland, and the Dow chemical company of Michigan buys.When using pore forming material, the consumption of pore forming material is according to different variation of mode of algae suspension dehydration.Usually, the consumption of pore forming material changes between 5-25ppm.

Yet, should be emphasized that, from Dunaliella salina, reclaim in the process of carotenoid, generally do not need to use pore forming material.Though do not wish to be confined to theory, can think that algae contains the compound of enough concentration, and have the surfactivity ability that in saturated brine, produces rill.

Algae in the feedstream can be collected device and compressor is regulated, to improve the selectivity of flotation.For example, improving rill is feasible to Dunaliella salina rather than to salt tolerant bacterium or other unwanted competitive algae or predator's adsorption selectivity.Collector is assembled frond, and absorption or adsorb them in foam surface, so that frond can be collected with foam.On the other hand, compressor is assembled unwanted composition in the suspension, repels them basically and is adsorbed on the foam.The use of compressor is feasible, otherwise a lot of impurity will be recovered with algae.

Setting accelerator comprises synthesized polymer and ion setting accelerator.The ion setting accelerator generally comprises alum or iron(ic) chloride.Usually, it is feasible not using setting accelerator.Setting accelerator is unnecessary in the invention process.But, the present invention many aspect, their use is to determine as the case may be, and also may be favourable.For example, the use of setting accelerator can improve the rate of recovery of algae composition in the thick-layer filtration medium sometimes.IV. mechanical filter is to separate algae from growth medium

According to Fig. 1, method of the present invention can comprise various filtration steps selectively.Before absorption bubble separates algae in the salt solution and afterwards under the both of these case, shown in step 24 and 28, all can use mechanical filter respectively.Usually, before the absorption bubble separated, algae suspension can filter by thick-layer and concentrate.At absorption bubble after separating, algae suspension can concentrate by microfiltration.But, should be realized that any in these filtration steps all can use before or after absorption bubble separating step, and in some cases, perhaps absorption bubble separating step is unnecessary.Yet, effectively carrying out during algae suspension concentrates in the mode that obtains the algae composition, the absorption bubble separates normally most economical a kind of.

It is a kind of extremely economically feasible ultimate technology of algae suspension that is used for concentrating that thick-layer filters, and this ultimate value is only to contain about 1% solid in the feeding liquid.Surpass this ultimate value, it will be uneconomic that thick-layer filters.Along with the increase of solids content, need will get more and more by the number of times of countercurrent washing, to remove the solid in the filtration medium.It is also increasing to force liquid to pass through the pressure of tower during filtration.Therefore, thick-layer filters usually and carried out before the absorption bubble separates, and is used for concentrating algae suspension, if carry out the almost not effect of this step at absorption bubble after separating.

Algae suspension, was realized through a granular media layer filtering to dirty by gravity then during thick-layer filtered, and this granular media is normally husky.Algae is retained in the slit between the hole neutralization medium particle of granular media.

Thick-layer filters should not be considered to coarse filtration.Coarse filtration is only carried out at screen cloth or fiber surface.And thick-layer filters particulate is kept somewhere in each of whole filtering layer inside might be detained hole and slit from the algae cell in the suspension that flows through.

Suitable thick-layer filtration medium comprises: common medium such as quartz sand, pomegranate stone sand, hard coal, glass fibre and their mixture that uses in commercial process.These media can obtain spissated valuable components so that separate by the absorption bubble further with clear water or salt water washing with the recycle-water frustule.

Medium also can contact with solvent to reclaim the valuable components in the captive algae cell.Extracting the solvent of describing in the content of carotenoid by Dunaliella salina hereinafter can be used for thick-layer too and filters from frond composition like the extract phase.

Complete cell or the composition in the ruptured cell all can filter by thick-layer and reclaim.Complete cell can make cell coagulate wadding before filtration and reclaim.But if cell breaks before filtration, the rate of recovery will increase significantly so.The algae stock suspension that is at least 0.002 milligram of carotenoid/mL of saline with content is carried out enforcement of the present invention, can obtain surpassing 70% the carotenoid rate of recovery.Use the filtering example of thick-layer to see the description of embodiment part among the present invention.

For some leaching process or owing to the needs of other reason, the carotenoid concentration in the Dunaliella salina can be increased to above thick-layer filter or the sepn process of absorption bubble in feasible ultimate value.Usually, the sepn process of absorption bubble has a feasible upper limit, and promptly the peak concentration of carotenoid is no more than 10,000ppm.For some viable economically purge processes, as the high density gas leaching process, in the algae suspension concentration should exceed of carotenoid about 10,000ppm.

Microfiltration can increase the concentration of carotenoid in the Dunaliella salina salt aqeous suspension, and can surpass usually that bubble separates available concentration, and this concentration is to calculate with the order of magnitude that carotenoid in the penetrant does not have the loss of measuring.When implementing microfiltration in the present invention, it is about 20 that concentration can reach, 000ppm.Fig. 3 has represented a kind of sketch of cross-flow microfiltration process.The equipment of use Fig. 3 carries out microfiltration and sees embodiment part of V II C for details.

As shown in Figure 3, Dunaliella salina salt aqeous suspension, the suspension that for example obtains from bubble cell injects holding tank 62.Suspension is transported to cross-flow microfiltration device 66 by pump 64.Before entering strainer, heat exchanger 68 can optionally be used for cooling suspension.Microfilter is furnished with by porous-film equipment and forms, and algae suspension is pumped along porous-film.Typical film can contain stupalith such as zirconium white, and common absolute scale is less than 10 microns.

Filter membrane is normally cylindrical, and suspension then is pumped through this right cylinder.Salt solution is removed by pipeline 69 as penetrant by film.Frond is retained in the suspension, as retentate by right cylinder after pipeline 70 be recovered.Retentate can be transported back holding tank, and cycles through strainer repeatedly up to obtaining enough concentration.In addition, retentate can be transported to another step of microfilter or directly be transported to extractor by pipeline 72.

The carotenoid sphere diameter generally can be found to have in penetrant to lose usually less than 1/10th microns significantly.Frond in the suspension that obtains by froth flotation equipment is disruptive normally, and suspension is gel a little, easily very fast obstruction filter membrane.Yet by implementing method of the present invention, carotenoid is difficult for detecting usually in penetrant, and effluent is after initial drop, and the amount of the effluent by filter membrane keeps constant basically, and need not to improve pressure drop.

Clear water can join in the feedstream or in the retentate, to reduce the salt concn of suspension.Additional filtering and dilution step can increase as required, to obtain required final salt concn and the carotenoid concentration in the retentate.The dilution process of carrying out after the filtration is sometimes referred to as: " diafiltration (diaflitration) ".The effluent of microfiltration and diafiltration and the curved line relation of time are also partly described embodiment hereinafter as shown in Figure 4 simultaneously.V. absorption bubble partition method is carried out algae dehydration A. general introduction

As shown in Figure 1, through the step 22 of algae cell rupture with optionally behind the filtration step 24 and 28,,, then be necessary to adsorb bubble and separate to concentrate algae suspension according to step 26 if if carrying out filtering words has also seldom.

Absorption bubble separates that the algae cellular material optionally adsorbs in its surface when being based on bubble flow and crossing aqeous suspension.Bubble floats the formation foam, takes away the algae material, normally distillates from cat head.Absorption bubble separation method is suitable for removing a spot of algae from a large amount of salt solution.

Various absorption bubble isolation technique are arranged, and some of them have foam to produce, and some does not have foam to produce.A kind of absorption bubble isolation technique that is used to algae is dewatered is a dispersed gas flotation body technology, is called " pneumatic flotation ".The sketch of the pneumatic flotation technology of gas dispersion in liquid is seen Fig. 5.

The another kind of absorption bubble isolation technique that can implement to use in the present invention is electro-flotation method and gas dissolved flotation process.Yet, should be realized that there is limitation in force in these methods, and they also there is no need with dispersed gas flotation body method the effect that is equal to is arranged.In electro-flotation method, the electric current feeding is about to separate in the aqueous substratum of algae, can produce bubble.If aqueous substratum is spissated salt solution, producing bubble needs big relatively electric current.In the gas dissolved flotation process, in independent container, under pressure, gas is dissolved in the part material stream, then the mixture that forms is imported flotation vessel.A unexpected pressure drop can cause the gas dissolved assembly, forms rill.The solubleness of air in salt solution is limited, and other does not have impregnable more soluble gas can select to use to carotenoid yet, as helium.B. pneumatic flotation

As shown in Figure 5, froth flotation equipment comprises foam generating area 84, collecting region 86, disengaging zone 88 and froth zone 90.Part or all of these zones can also can be in different containers in same container.When feedstream 80 enters froth flotation equipment,, collecting region 86 can be at first entered, also foam generating area 84 can be at first entered according to used equipment difference.In both cases, gas all after the foam generating area is scattered in algae suspension, enters collecting region and forms the gas-liquid two-phase dispersed system.Producing a large amount of rills needs to reach maximum gas table area, like this, in the algae suspension of a constant volume, is beneficial to the collision of bubble and frond.

At collecting region, under the condition that promotes closely contact, algae suspension contacts with rill.Bubble and frond collision form bubble algae aggregation.Carrying out violent mixing at collecting region needs with the frequency that improves collision.

Bubble and algae aggregation after collecting region forms, generally by action of gravity, they in the disengaging zone 88 with do not contain the salt water sepn of algae.Gas density is less than 2 to 3 orders of magnitude of brine density.The difference of density impels bubble and algae aggregation to float on Gas-Liquid Dispersion surface mutually, accumulates with the foamy form at froth zone 90.

The foam that is rich in carotenoid overflows froth zone along flowing out line 93.Collection rinse bath 122 among Fig. 6 generally is used to receive the overflow substance of froth zone, foam fragmentation in rinse bath.Substrate streamline 92 is effusive to be the salt solution that does not contain algae.The bottoms stream line effluent of floatation equipment can repeat to reclaim or abandon.

It should be nontoxic being used to adsorb the suitable gas that steeps separating device, as air, nitrogen, carbonic acid gas, helium, argon gas be considered to chemically inert rare gas of tool and their mixture other.The rare gas element of oxygen-free gas or oxygenant is preferred for the extraction of carotenoid, in order to avoid carotenoid is oxidized in tenuigenin.C. pneumatic flotation circulation

Use froth flotation equipment can make the rate of recovery of valuable components in the algae and concentration reach maximum in the flotation circuit.Energy investment higher relatively in the floatation process can be compensated by high-recovery and the high density that adopts flotation circuit to obtain.

Fig. 6 has represented the pneumatic flotation circulation briefly, and the foam flotation tower that will be used for the air-flow pneumatic flotation is connected in series.But, should be appreciated that illustrated principle can be applicable to comprise machinery and air-flow froth flotation equipment pneumatic flotation circulation.

The foam circulation process that Fig. 6 represents comprises to be roughly selected district 94, selected district 96 and scans district 98.The function of flotation vessel depends on its trizonal which position in circulation.Algae suspension enters coarse classifier 100 as incoming flow 102.Overflow substance in the coarse classifier provides incoming flow 104 for first preparator 106.The algae concentrated solution flows out by materials flow 110 from whole preparator 108.The incoming flow 112 of scavenger 114 is just provided by the substrate effluent of first preparator 106, has improved the rate of recovery of carotenoid.The salt aqueous waste solution that does not contain algae is discharged from the bottoms stream 118 of coarse classifier 100 and the bottoms stream 120 of whole scavenger 116 respectively.As required, use multistage preparator and multistage scavenger that best product recovery rate and concentration can be provided.As required, can not use scavenger.In addition, the bottoms stream thing 118 of coarse classifier can the behavior incoming flow be supplied with the machine 114 that just all selects, so that processing in scanning district 98.In this case, if desired, the bottoms stream thing of first preparator 106 also can reclaim and enter coarse classifier 100, perhaps discharges as waste liquid, perhaps as the charging of scavenger just.1. roughly select

The function of coarse classifier 100 is as the elementary pneumatic flotation of roughly selecting district 94, is used to separate algae and salt solution.The purpose of coarse classifier is to produce the high algae rate of recovery, and suitably increases concentration.Therefore, coarse classifier is generally guaranteeing that value product obtains to move under the highest rate of recovery and the moderate concentration conditions.The operational conditions that is used as the floatation equipment of coarse classifier is compared with the floatation equipment as preparator, and the flow velocity of surface gas is higher usually, and depth of foam is less.

Will be from the source of algae such as natural lake or pond, or acquisition algae suspension pump is delivered to coarse classifier as raw material 102 in some other source as intensive and the extensive cultivating pool.Suspension can adopt above-described ruptured cell or mechanical filter brinish step to carry out pre-treatment as required.That live, complete cell or disruptive cell or their mixture all can enter coarse classifier.If there is not cell rupture step in advance, the use of coarse classifier can make the most of cell in the raw material break in coarse classifier.

The surface that bubble that produces and algae aggregation float over gas and liquid suspension, they can be used as spissated foam and are collected.Enriched material overflow from coarse classifier enters collects washing machine 122, enters holding tank 252 then, as shown in figure 11.The bottoms stream thing 118 of coarse classifier can be sent back to place, salt solution source or be abandoned, or further handles by one or more levels floatation equipment that is arranged in parallel.2. selected

Leaving the algae suspension 104 of roughly selecting district 94 as the overflow substance of coarse classifier 100 can be by placed in-line one or more preparators 106,124 and 108 further enrichment carotenoid.The purpose in selected district is the algae enriched material that is rich in carotenoid that produces favourable recovery.The algae cell concentration is in the foam that each

preparator overflows.Preparator

106 and 124 overflow substance provide the raw material of next preparator.The bottoms stream thing generally is recovered the raw material as the preparator of front.Usually, when carrying out flotation, can obtain the carotenoid of concentration at least about 2000ppm with method of the present invention.

Selected district can comprise single pneumatic flotation container or comprise a plurality of containers that serial or parallel connection receives feedstream.The bottoms stream thing of preparator can be dropped, return the coarse classifier district, return the front preparator, handle by one or more scavengers of serial or parallel connection or according to the concentration of carotenoid in the bottoms stream thing.3. scan

In scanning district 98, the carotenoid of losing in the bottoms stream thing can be collected to obtain maximum product recovery rate.The enriched material 126 of scanning district's acquisition is recovered and enters selected district, and the bottoms stream thing of scanning the district is dropped or returns place, salt solution source usually.Scanning the district can comprise single pneumatic flotation container or comprise a plurality of containers that serial or parallel connection receives feedstream.

As shown in Figure 6, scan district 98 and comprise 3 placed in-line scavengers 114,128 and 116.The description that the raw material supplying of scavenger sees

above.Scavenger

114 and 128 bottoms stream

thing

130 and 132 provide the raw material in the next series connection scavenger respectively.The overflow substance 126 of each scavenger is as the raw material in selected district.D. common machinery and air-flow flotation cell

The suitable foam floatation equipment comprises the equipment of the commercial contact for gases and liquids that can obtain.These equipment are also referred to as " groove ", can be divided into two kinds of main classifications: mechanical flotation cell and air-flow flotation cell.The stator and the rotor structure that can disperse gas and can provide enough bubbles to contact with algae be provided mechanical flotation cell.In the mechanical flotation cell that turns round under enough speed, the shear field that wheel rotor produces can make frond break.When impeller turned round under enough speed, the step of independent ruptured cell there is no need.

The maximum difference of air-flow flotation cell and mechanical flotation cell is whether rotary blade is arranged in the floatation equipment.In the air-flow floatation equipment, the collision of bubble and algae is only caused by the gas that feeds, and does not have other running gear.Usually before the air-flow flotation, algae broken and be necessary.But when the air-flow flotation cell moves under suitable condition (hereinafter will describe), frond can break in groove.Air-flow flotation cell subsequently can be operated as preparator and scavenger, because frond breaks, there is no need to carry out under similar condition.

According to equipment performance with separate purpose, use arbitrary or all positions that air-flow and mechanical flotation cell can be in the pneumatic flotation flow processs.But the air-flow flotation cell has advantage than mechanical slot usually.Under certain device capacity and energy expenditure, gas flow equipment is compared with mechanical means, and gas flow equipment can obtain the higher rate of recovery and turnout, therefore can reduce the cost of fund and operating aspect.Gas flow equipment can be made by plastics in light weight, that price is low, can further save fund, improves mobility.These advantages and some other advantage will further describe hereinafter.

Machinery described herein and air-flow flotation cell have several common operating parameters, as the surface velocity J of gas phase _g, gas and raw material ratio, residence time, the consumption of flotation aid and the character of flotation gas of liquid in flotation unit.Several design variables also have various froth flotation equipments, as the depth-width ratio of collecting region, the depth-width ratio of disengaging zone, the method that contacts as and stream, adverse current, cross-stream and mechanically mixing, separate bubbles and the method for algae aggregation and the method that produces bubble from slurries.

The performance of froth flotation equipment can quantize according to the carotenoid concentration in the foam and the carotenoid rate of recovery.Each froth flotation equipment all has several specific geometry parameter and operating parameters, but above-mentioned significant parameter is that whole method for floating described herein field is common.1. mechanical flotation cell

The flow dynamic characteristic of mechanical flotation cell 134 is seen Fig. 7.Mechanical slot adopts stator and rotor structure 136 to import gas usually, forms bubble, makes bubble and algae collide by the mobile of liquid.The ratio of container height and diameter is called " depth-width ratio ", changes between about 0.7 and 2 usually.Typically, the groove of four or more similar Fig. 7 is connected to be provided with and can be realized sufficient mixing basically, makes the short-circuit cycle of liquid phase reach minimum simultaneously, and stator and rotor structure 136 all are equipped with in the middle part of each groove.Auxiliary gas blower can be installed usually provide enough gas in the groove.

Collecting region 150 and disengaging zone 152 are all in the same container of mechanical slot.If desired, mechanical slot can seal so that operate be more prone to carry out and reclaim basically can not oxidation carotenoid gas.

By rotary blade 138, i.e. bubble generator, gas is dispersed into rill.Rotary blade can produce a low pressure area, make gas pass through air suction pipe 148 and flow into collecting regions 150, along with gas from flowing that trench bottom makes progress, be dispersed into rill, mix with algae suspension.

Algae suspension enters mechanical slot as incoming flow 140 by material feeding box 141.Bubble contacts by the turbulent flow that rotary blade produces with algae.Bubble leaves collecting region 150 with the algae aggregation and enters relative immobilized disengaging zone 152, and they float on the surface of liquid phase and realize separating.

Bubble and algae aggregation be by gravity and liquid phase separation, then at the froth zone 154 at the groove top foam of carotenoid of having collected enrichments.Enrichment the foam of carotenoid be recovered as algae concentration logistics 144.Foam overflows groove usually and enters the collection washing machine.In addition, foam also can reclaim by mechanism, as froth paddle.Liquid phase is then passed back into collecting region, and the salt solution bottoms stream thing 146 that final conduct does not contain algae leaves this groove.

The stator of appropriate design and rotor structure can produce quantitative gas, and this gas dispersion is become rill, and make gas and liquid mixing, realize enough contacting between algae and the bubble.In two phase mixtures, obtain high collision frequency of bubble and algae and good flotation performance, need good mixing and enough liquid hold-up time.

J _gDefinition in mechanical flotation cell be the capacity gas flow rates/with the cross-sectional area of the foam groove parallel with the liquid phase interface.Along with J _gThe increase of value, the hold-up of gas in liquid phase also increases, and the hold-up in foam reduces, and can obtain flotation power faster, but the concentration of carotenoid (not calculating gas) reduces in foam.For for extracting carotenoid the Dunaliella salina, J _gCan between about 0.1 to 5cm/s, changing of value.J _gValue preferred about 2 is to 4cm/s.

The liquid hold-up timing definition is the volume/liquid capacity flow velocity of disperse phase in the mechanical slot.The long residence time can obtain the higher carotenoid rate of recovery in foam.For for extracting carotenoid the Dunaliella salina, the residence time is about 3 to 12 minutes.Residence time is preferably about more than 5 minutes.

The benefit that the ratio of gas and raw material is little comprises: reduce the capacity of equipment and the cost of the gas blower in the saving mechanical slot.For for extracting carotenoid the Dunaliella salina, the ratio of gas and raw material is about 5 to 20.The ratio of gas and raw material preferably about 5 to 15.

The terminal velocity of impeller influences the size of bubble and passes through the circulation again of collecting region.Along with the increase of terminal velocity, bubble size diminishes, by the increase of circulation again of collecting region.But high terminal velocity may cause bigger mechanical loss, and the required power of drives impeller is higher.Bubble and algae aggregation can break under high terminal velocity.For for extracting carotenoid the Dunaliella salina, terminal velocity is about 900 to 2500 feet per minute clocks.Preferably about 1500 to the 1800 feet per minute clocks of terminal velocity.The terminal velocity that surpasses about 1500 feet per minute clocks is favourable for the frond that breaks.

Mechanical flotation cell has four main geometry parameters.These geometry parameters are: the 1) ratio of the submergence of rotor and liquid depth, 2) ratio of groove diameter and impeller diameter, 3) ratio of liquid depth and groove diameter, 4) design of rotor and stator structure.For for extracting carotenoid the Dunaliella salina, the submergence of rotor and the ratio of liquid depth are about 0.7 to 0.75.The ratio of groove diameter and impeller diameter is about 1.5 to 5.5.Often the groove diameter that uses and the ratio of impeller diameter are about 2.The ratio of liquid depth and groove diameter is about 0.6 to 0.9, and preferred 0.8 to 0.9.

Rotor and stator structure comprise: by Dorr-Oliver Incorporated ofMillford, the product that Connecticut makes, by Svedala of ColoradoSprings, the product that the Denver Equipment Company of branch office of Colorado makes, by Wemco Products of Salt Lake City, the product that Utah makes and by Outomec Oy of Espoo, the product that Finland makes.2. air-flow flotation cell

The air-flow flotation cell is different from the flotation cell of mechanical agitation in many aspects.Bubble all can produce by any mechanical system well known in the prior art in airslide.Bubble can pass through perforated pipe foam generating device, throttling orifice plate, Venturi tube or static mixer and produce.When using static mixer, adopt foaming agent solution to mix usually with gas.

Some airslides are compared with mechanical slot, and they can produce thinner bubble.Therefore, in airslide, collision frequency is higher, and required residence time of flotation is shorter usually.

Air-flow flotation cell, particularly flotation tower have bigger depth-width ratio than mechanical slot usually.The container height of airslide and the ratio of diameter are also bigger usually.Gas flow equipment can produce thicker foam layer usually, correspondingly needs to increase drain time and moisture eliminator, to obtain more spissated foam.Because the height of container is usually greater than the diameter of container, washing lotion can

Join in the foam to improve the purity of product.

The air-flow flotation cell is that in light weight, material and laid down cost are low with respect to another advantage of mechanical slot.The air-flow flotation cell can be made by the low light plastic of price, and owing to do not have impeller and driving arrangement, weight and cost can further reduce.Because the generation of bubble and gas all do not need to use mechanical rotor and stator module with contacting of liquid, the investment of air-flow flotation cell and running cost also have tangible reduction than mechanical slot.

Generally speaking, collecting under the limited situation, perhaps under the limited situation of weight-carrying capacity, all can operate as the air-flow flotation cell of preparator.Collecting under the limited situation, the collecting amount of particulate is subjected to collision number quantitative limitation between bubble and the algae.Under the limited situation of weight-carrying capacity, bubble surface is saturated by the algae material.Therefore, the collecting amount speed of particulate is joined the surface-area size restriction of the bubble in the tower.Can reach minimum owing to be used for the brinish volume of leaching process, be favourable by the saturated bubble of algae material almost so form the surface.

According to Fig. 5, if desired, feedstream can pass through machinery or chemical treatment, makes algae be easy to flotation more.In the bubble generation district, by bubble generator, gas is dispersed into rill.The inside that bubble generator can be installed in froth flotation equipment also can be installed in its outside.An example of built-in bubble generator is the perforated pipe foam generating device.An example of external bubble generator is a static mixer, and foaming agent solution mixes with gas in the mixing tank.

Bubble and algae suspension enter collecting region, and bubble and algae collision form bubble algae aggregation.Bubble and algae can be by gas phase and liquid phase adverse current or and stream or mix by air-flow and to realize collision.Aggregation floating by the disengaging zone to liquid phase and foamy interface, flow into froth zone, increase sharply at this gas hold up.

Foam can contact with washing lotion, so that separate hydrophilic particulate and the supplementary feed that is pulled away in the algae from foam.Foam is rich in biomass and leaves equipment.Liquid phase is discharged from as the bottoms stream thing that does not contain biomass in device bottom.

Air that can be recycled or inertia flotation gas are easy to use in the air-flow floatation equipment.Collect the washing machine gas that promptly can be recycled by sealing.Pore forming material can be added in liquid phase or the gas phase to produce rill.

There are several air-flow floatation equipments can be in algae of the present invention dehydration and from Dunaliella salina, carry out using in the process that carotenoid reclaims.These equipment comprise having the tower than large ratio of height to width, and it has many advantages of said flow equipment.Some air-flow flotation cells and their uses in the present invention will be described below.

The air-flow flotation cell comprises hydrocyclone or " ASH " that induces gas flotation groove and injection air.In inducing the gas flotation groove, together by the nozzle ejection of trench bottom, gas promptly is dispersed in the liquid with liquids and gases.ASH utilizes gas to shift by a porous wall and forms foam, foam overflow and going out.The a.Jameson groove

The Jameson groove 156 of single downspout conductor as shown in Figure 8.The Jameson groove is in U.S. Pat 5,188,726, US5, and open in 332,100 and US4,938,865, used these contents are also listed this paper as a reference in.For carrying out the carotenoid extraction the Dunaliella salina, the algae material accounts for 60ppm to 13% (not calculating gas) in the foam that the Jameson groove produces for of the present invention.

The Jameson groove is made up of two main members.First member is a downspout conductor 158, and normally diameter is about 100 to 280 millimeters, is about 3 meters post.Second member is upper reaches pipe 160.The upper reaches pipe is the groove that a downspout conductor injects.The diameter of upper reaches pipe is usually greater than the diameter of downspout conductor.In addition, a plurality of downspout conductors can inject same upper reaches pipe.

The downspout conductor of Jameson groove defines collecting region 86 (Fig. 5), and its depth-width ratio is about 10 to 30 usually.The upper reaches pipe comprises disengaging zone 88 (Fig. 5) and froth zone 90 (Fig. 5), and its depth-width ratio is about 0.5 to 5 usually.Contacted method is a heterogeneous downwards and stream in downspout conductor.Bubble and algae aggregation in the pipe of upper reaches by action of gravity with do not contain the salt water sepn of algae.By high-velocity jet, gas entrainments in liquid phase and disperses, so produce bubble in downspout conductor.

Algae suspension enters the downspout conductor top by pipeline 162, by throttling orifice plate 164, forms the high-speed liquid injection stream.Because the pressure of downspout conductor reserving space 166 makes gas enter the downspout conductor reserving space by pipeline 168 less than normal atmosphere.The gas that sprays clashes into liquid in downspout conductor surface makes gas be brought in the liquid phase.By the lost high-speed gradient that produces of the momentum of jet-stream wind, entrapped gas can be dispersed into rill.With the form of two-phase flow, gas and liquid flow are crossed downspout conductor.The two-phase flow form approaches the downward also plug flow of stream in vertical tube, makes the collision of bubble and algae form bubble algae aggregation.Heterogeneous dispersion liquid, the bottom of process downspout conductor enters the upper reaches pipe.

During the operation of Jameson groove, the liquid plane 170 in the pipe of upper reaches is higher than downspout conductor end 172 a little, forms a hydraulic seal state.Bubble and algae aggregation are in upper reaches Guan Zhongyu salt water sepn.Aggregation floats on the upper reaches tube-surface, is collected to enter with the foam 174 that overflows groove and collects washing machine 176.The salt solution that does not contain algae goes out from the bottom land logistics as materials flow 178.

Product concentration reaches best in product recovery rate and the foam in order to make, and the upper reaches pipe is projected depth as required.Because diameter can be taken away aggregation less than about 500 microns superfine bubble in bottoms stream 178, the upper reaches pipe needs certain degree of depth to avoid the generation of this phenomenon.For the operation of high-recovery, the foamy degree of depth can be lower than 50 milliliters, but is generally 300 to 800 milliliters.Washing lotion 180 can add in the foam to improve enriched material purity.The Jameson groove can be operated under air conditions, also can be in making the minimum gas of carotenoid degraded closed-loop operation.

Usually, superficial gas velocity, J in the operational condition of Jameson groove, especially the upper reaches pipe _g, can change according to different purposes, as roughly select, scan or purify.

The J of Jameson groove _gBe defined as the superficial gas velocity in the pipe of upper reaches, it equals gas volume flow velocity/upper reaches pipe cross-sectional area parallel with the liquid phase interface with foam.To groove J _gSelection can be so that bubble fully separates in the pipe of upper reaches with the algae aggregation, can make foam stabilization simultaneously.J _gIn the foam flooding point maximum value is arranged, at this moment, equal at the gas hold up of disengaging zone and froth zone, interface disappears.At high J _gUnder the value condition, before the groove generation overflow, bubble and algae aggregation obviously are brought into bottoms stream 178, and illustrating to reclaim has loss.J _gMinimum value determine according to the demand that produces stable foam.If gas flow rate is too small, foam is easy to break, and seriously causes aggregation to be brought into disengaging zone in the upper reaches pipe 160 repeatedly.

Superficial gas velocity depends on system characteristic and its purposes in the pipe of upper reaches.Be used for roughly selecting the dehydration of Dunaliella salina, J _gValue is about 0.1 to 1.0 cel.J in the coarse classifier _gBe worth preferred 0.3 to 0.5 cel.Be used for the dehydration of selected Dunaliella salina, J _gValue is about 0.05 to 0.5 cel.J in the preparator _gBe worth preferred 0.1 to 0.35 cm per minute.

Superficial gas velocity is relatively low, and partly cause is to have tensio-active agent in the algae at least.The tensio-active agent of high density can cause at low J _gFoam overflow under the value condition.Be during pneumatic flotation carotenoid, only to need so low J astoundingly _gValue.Be more astoundingly, natural pore forming material has so high concentration and has the surfactivity ability that makes carotenoid be easy to flotation in the algae, even in the saturated salt solution of sodium-chlor.

The downspout conductor surface velocity of Jameson groove can be calculated by the cross-sectional area of raw material flow rate and downspout conductor and obtain.The downspout conductor residence time is a parameter that is closely related, and it is defined as downspout conductor volume/raw material volumetric flow rate.These two parameters value directly influence the turnout and the performance of equipment.The long residence time also means low surface velocity, can improve the effect that algae is collected, thereby carotenoid has the high rate of recovery in foam.The treatment capacity that short residence time and big surface velocity can increase tower.

For for reclaiming carotenoid the Dunaliella salina, the downspout conductor surface velocity is about 0.1 to 0.4 meter per second.The downspout conductor residence time is about 9 to 30 seconds.For for reclaiming carotenoid the Dunaliella salina, when Jameson groove during as coarse classifier and scavenger, the value of downspout conductor surface velocity and residence time is about 0.15 to 0.3 meter per second and about 10 to 20 seconds respectively.When the Jameson groove when the preparator, the value of downspout conductor surface velocity and residence time is about 0.1 to 0.2 meter per second and about 15 to 25 seconds respectively.

The ratio of gas and raw material is defined as the ratio between gas volume flow velocity and the liquid capacity flow velocity.Have the more rill of homogeneous of distribution of sizes owing to formed, the ratio of gas and raw material reduces and will have stabilization to tower in the Jameson groove.Along with the increase of the ratio of gas and raw material, the thick bubble that specific surface is little and distribution of sizes is wide will form.Finally, it flows downward vis-a-vis and rises to form air pocket.

For for reclaiming carotenoid the Dunaliella salina, when the Jameson groove was used as coarse classifier, scavenger and preparator, the ratio of gas and raw material all was about 0.3 to 0.9, and preferred about 0.4 to 0.7.

Feed pressure in the downspout conductor ingress has determined the speed of spraying.For for reclaiming carotenoid the Dunaliella salina, be beneficial to flotation by the mechanical pretreatment algae of breaking, its feed pressure is about 20 to 60 pounds/square inch.For the Jameson groove is used as coarse classifier and scavenger, preferred about 50 to 60 pounds/square inch, for it is used as preparator, preferred about 20 to 25 pounds/square inch.

For for reclaiming carotenoid the Dunaliella salina, for coarse classifier, scavenger and preparator, jet velocity is about 8 to 25 meter per seconds, for for coarse classifier and scavenger, preferred about 10 to 20 meter per seconds, for for preparator, preferred about 8 to 15 meter per seconds.

For the Jameson groove, two kinds of design proportion are arranged: the ratio of the ratio of downspout conductor diameter and throttle orifice diameter and upper reaches pipe diameter and downspout conductor diameter.For for reclaiming carotenoid the Dunaliella salina, the diameter proportion of downspout conductor and throttle orifice is about 7 to 13, and preferred 8 to 10.For for extracting carotenoid the Dunaliella salina, the upper reaches pipe is about 2 to 10 with the diameter proportion of downspout conductor, is preferably greater than 5.

For saving the independent step of breaking, under high feed pressure condition, can move the Jameson groove.The operation Jameson groove algae of can breaking at mouth of pipe place under high feed pressure is also without any need for impelling algae to be easy to the machinery or the Chemical Pretreatment step of flotation.The feed pressure that is higher than 60 pounds/square inch is called high feed pressure.Usually, the Jameson groove moves to be used for ruptured cell under about 150 to 300 pounds of/square inch feed pressures.

By the throttling orifice plate than normally used more aperture is installed at the nozzle place, the Jameson groove can move under the feed pressure more than 60 pounds/square inch.But the bubble that high jet velocity usually produces is meticulous so that can not be separated in the pipe of upper reaches, and causing has bubble and algae aggregation to be pulled away in bottoms stream 178 (Fig. 8).Under high feed pressure, move, be necessary to install a divergence form nozzle or inducer to change the downward momentum of injection stream.

Injection stream can be calculated by Bernoulli equation by the speed of downspout conductor top throttle orifice.Injection stream is made up of three districts: free jet, volume jet and mixing zone.When raw material entered downspout conductor by throttling orifice plate, raw material was the form of free jet.Free jet has produced low pressure area at reserving space, and gas transfer arrives the injection stream surface.The zone of injection stream bump fluid surface is called the volume jet, is involved in the liquid at this regional gas.In the mixing zone that is lower than fluid surface, the momentum of injection stream is scattered and disappeared.The high-speed gradient that forms is smashed the gas that is involved in, and forms rill.B. multi-stage circulating-flow flotation tower (MSTLFLO)

Multi-stage circulating-flow flotation tower 182 is seen shown in Figure 9.MSTLFLO is an improved bubble column, is made up of following each several part: atomizer 184 is used for gas is imported tower bottom; A string vertical inducer that is installed in the tower, drainage tube 186,188 and 190; Lay respectively at the inducer 192,194 and 196 at drainage tube 186,188 and 190 tops, to produce suitable water power; Feed distributor 198; With the concentric collection washing machine 200 of tower.The MSTLFLO tower is by D.X.He, F.X.Ding, H.Hu and S.H.Chiang disclosed in the 5th being entitled as in " A Multiple-loopFlotation Column for Wastewater Treatment " article of volume 133-188 page or leaf of " SeparationsTechnology " nineteen ninety-five.The full content of people's such as He article is also listed this paper as a reference in.

The primary features of MSTLFLO tower is the assembling of multistage drainage tube.Spray in the drainage tube 186 at the bottom of the tower from the gas of pipeline 185, the gas hold up that produces in this drainage tube gas hold up interior than the annular zone between drainage tube and the tower wall 202 is bigger.The difference of gas hold up forms a circulation pattern.Upwards flow in gas and the zone 204 of liquid dispersion in drainage tube, this regional function is equivalent to the upper reaches pipe, and flows downward in annular zone 202, and this regional function is equivalent to downspout conductor.Mobile in downspout conductor approach heterogeneous downwards and the plug flow of stream.Reduced more homogeneous of size distribution that axial blended cycling stream water power can make bubble.With respect to the conventional bubble flotation tower (also claiming the Canadian tower) that does not contain drainage tube, the flotation power of MSTLFLO tower obviously improves.Bubble column as shown in figure 10.The MSTLFLO tower can repack bubble column into by the removal drainage tube.

The collecting region 86 of MSTLFLO tower and disengaging zone 88 (Fig. 5) are in same container.The depth-width ratio of this container is greater than 5.Though bound by theory not, the collecting region of MSTLFLO tower can be considered to the downspout conductor and the upper reaches pipe of each drainage tube, are heterogeneous and fluidization tower plug flow in the drainage tube.The disengaging zone of tower is to be positioned on the feed distributor 198, is positioned at below the gas-liquid interface.

Aggregation accumulates in the froth zone of foam and liquid interface top and overflows tower, enters and collects washing machine 200.Lather collapse forms spissated algae suspension, and it reclaims by pipeline 206.The salt solution bottoms stream that does not contain algae is drained by pipeline 208 at the bottom of tower.

In the MSTLFLO tower, superficial gas velocity J _gBe defined as gas volume flow velocity/tower cross-sectional area.Along with J _gIncrease, gas hold up in heterogeneous dispersed system increases, the algae collecting effect improves.But, along with J _gIncrease enter in the foam because the bubble band that rises more water, cause the gas hold up in the foam to reduce.Work as J _gWhen being worth near maximum, the gas hold up in the foam in the gentle liquid dispersion system of gas hold up equates, causes the tower overflow, and interface disappears.

For for reclaiming carotenoid the Dunaliella salina, J _gValue is about 0.1 to 1.0 cel, preferred 0.2 to 0.5 cel.Surprisingly, the flotation of carotenoid only needs so little J _gValue.More surprisingly, natural pore forming material has so high concentration and has the surfactivity ability that makes carotenoid be easy to flotation in the algae, even in the saturated salt solution of sodium-chlor and under the condition that other ion exists, all shows such characteristics.

The liquid hold-up timing definition is MSTLFLO tower volume/liquid starting material volumetric flow rate.The long residence time can be improved the rate of recovery of carotenoid in the foam.The short residence time can be improved the tower treatment capacity.For for reclaiming carotenoid the Dunaliella salina, to collect under the limited situation, the liquid hold-up time is about 2 to 20 minutes.Under the limited situation of weight-carrying capacity, the residence time was above 20 minutes.

In the MSTLFLO tower, use the benefit of little gas raw material ratio to comprise: the cost that reduces volume of equipment and pressurized gas.For for extracting carotenoid the Dunaliella salina, the ratio of gas and raw material is about 0.10 to 1.5, and preferred about 0.2 to 0.8.So little gas raw material ratio is wonderful, is favourable for the flotation of carotenoid.

Be reduced under the minimum inert gas conditions in the oxidation that makes the class Radix Dauci Sativae,, adopt the MSTLFLO tower more favourable as under carbonic acid gas, nitrogen, helium or rare gas condition.Compare with air, the use of carbonic acid gas can improve flotation power.

The use of multistage drainage tube can reduce the axial mixing in the tower, reduces short-circuit cycle, improves the performance of tower.For for reclaiming carotenoid the Dunaliella salina, the progression of drainage tube is about 1 to 5, preferably above 1 grade.

For for extracting carotenoid the Dunaliella salina, the ratio of drainage tube diameter and tower diameter is about 0.5 to 0.9, and preferred about 0.5 to 0.7.

Flotation carotenoid from Dunaliella salina can produce metastable foam, then needs the relatively large washing machine of cross-sectional area to hold foam.For for extracting carotenoid the Dunaliella salina, the ratio of washing machine diameter and tower diameter is 2, and this ratio usually should be greater than 1.25.The c.Canadian tower

The Canadian tower is also referred to as conventional tower or bubble column, as shown in figure 10.The diameter of bubble column 210 is about 0.5 to 3.0 meter usually, and height is about 9 to 15 meters usually.Sectional area can be for square or be circular.

Raw material algae suspension enters in the tower by the pipeline 212 that is lower than foam and liquid interface 214 about 1 to 2 meter, and to dirty.Gas is dispersed into rill by atomizer 218 usually at the bottom of pipeline 216 enters tower.Can use rare gas element, as carbonic acid gas, nitrogen, helium or rare gas, so that the carotenoid degraded is minimum.Gas, normally air can directly inject at the bottom of the tower, forms internal spray (shown in Reference numeral 218), or before injecting as outer jet, at first the mixture with water, algae suspension, foaming agent solution or their combinations contacts.The interior spray device is made by the perforated pipe that fabric (as cloth) covers usually, or is made by perforation rubber.

The adverse current of gas and algae suspension makes bubble and algae in collecting region 86 (Fig. 5) collision, and collecting region is defined as the zone of below, product distribution district 222 (Figure 10).The disengaging zone of tower is 214 the zone that is higher than product distribution district 222, is lower than foam and liquid interface.Aggregation accumulates in the froth zone of foam and liquid interface top and overflows tower, enters and collects washing machine 226.Lather collapse forms spissated algae suspension, reclaims by pipeline 228.The salt solution that does not contain algae flows out from tower L bottom as materials flow 220.

Tower can move under any required foam depth, yet the foamy degree of depth is generally 50 to 100 centimetres in practice.Washing lotion can join (shown in Reference numeral 224) in the foam, to separate the hydrophilic particulate that is swept away from the algae biomass.For obtaining best washing effect, tower moves under positive bias usually, this means that foam is crossed in the net inflow of a downward water.The bias voltage current flow out tower by bottoms stream.The flow velocity of bottoms stream should be greater than input speed, and is constant with the height of keeping foam and liquid interface.D. gas-sparged hydrocyclone (ASH)

According to the present invention, for for reclaiming carotenoid the Dunaliella salina, in the ASH unit, algae weight concentration in the foam (not calculating gas) is about 0.001% to 0.3%.ASH leads to the cylindrical highly compressed tangential admission mouth with porous wall by one and forms, and the gas of compression enters this equipment by hole wall.The foam base that tilts is positioned at the bottom of cyclone, so that the cross-sectional area of bottoms stream is easy to change.The vortex finder of various diameter can be used for the output speed of control foam.

Mode with tangent line enters ASH equipment to raw material at the cyclone top, and the path through a spiral arrives the bottom then, leaves by annular bottoms stream opening again.The hole wall that air passes through produces bubble.Collision between algae and the bubble occurs on the outer vortex, and this zone definitions is collecting region 86 (Fig. 5).Along with flow direction hydrocyclone bottom, gas phase contacts with the cross-stream pattern with liquid phase.Centrifugal force can make bubble, and 88 (Fig. 5) separate in the disengaging zone with the salt solution that does not contain algae with the algae aggregation, and undefined zone between inner vortex and the outer vortex can be thought in the disengaging zone.Bubble and algae aggregation are transported to froth zone 90 (Fig. 5), form inner vortex, move to the hydrocyclone top and overflow.

The J of ASH equipment _gBe defined as cross-sectional area by the gas volume flow velocity/dividing plate of dividing plate.For for reclaiming carotenoid the Dunaliella salina, J _gValue is about 0.7 to 6 cel, is preferably greater than 3 cels.

The liquid hold-up timing definition of ASH equipment is ASH volume of equipment/liquid capacity flow velocity.For for reclaiming carotenoid the Dunaliella salina, the residence time is about 1 to 10 second.

For for reclaiming carotenoid the Dunaliella salina, the ratio of gas and raw material is about 0.4 to 6, is preferably greater than 3.E.EKOFLOT air-flow flotation cell

Algae suspension 80 (Fig. 5) is pumped to the top of tower by pipe in the Wen, and the function of pipe is as bubble generation district 84 (Fig. 5) in the Wen.Gas is involved in the algae suspension, and the mixture of formation moves down by feed-pipe, and the collision between gas and the algae mainly occurs in the feed-pipe.Feed-pipe has been taken on the function of collecting region 86 (Fig. 5).By divider, the Gas-Liquid Dispersion system of containing bubble and algae aggregation enters disengaging zone 88 (Fig. 5), and the disengaging zone is in an independent container.Aggregation floats over the surface of froth zone 90 (Fig. 5), accumulates at froth zone.The salt solution that does not contain algae goes out container as materials flow 92 (Fig. 5) logistics.

Foam is scraped the machine of sweeping, and is turbination, can raise or reduce, and is used to change the size of foam area to reach optimal separating efficiency.Foam can contact with washing lotion, to improve the purity of product.The foam that purifies overflows container, enters the collection washing machine, and leaves the collection washing machine as enriched material.Be about 2 to 3 minutes in the residence time of disengaging zone, similar in appearance to the Jameson groove.But the residence time in Jameson groove downspout conductor is about 5 to 10 seconds usually.Residence time in EKOFLOT container inflation mechanism is a Millisecond.The inflation mechanism of EKOFLOT groove is the position that bubble and algae bump, and is defined as collecting region.F.Microcel ^TMThe microfoam flotation tower

Microcel ^TMTower is in U.S. Pat 4,981, and open in 582 and US5,167,798, used these contents are also listed this paper as a reference in.Microcel ^TMTower is by being positioned at Pittsburgh, the ICF Kaiser Engineers of Pennsylvania, Inc., manufacturing.Tower is made up of following parts: the inflation area at the bottom of tower; An one-way slabs that is positioned at inflation area top is used to make microvesicle to rise up among the liquid but stops solid to fall into inflation area from sediment; A collecting region; A froth zone.Algae suspension charging 80 (Fig. 5) enters in the tower from the position that is lower than the foam liquid interface, then to dirty.Gas 82 (Fig. 5) is scattered in the liquid by microvesicle generators in the tower outside, the function of microvesicle generators is as bubble generation district 84 (Fig. 5).Suitable liquid comprises algae suspension charging 80, bottoms stream 92, foaming agent solution or their combination.Atomizer by the outside produces microvesicle, and the microvesicle size is 50 to 400 microns.Then, microvesicle is imported into inflation area.

The liquid that is used to produce microvesicle flows out the inflation area that does not contain bubble by the aperture, is recovered and enters microvesicle generators.Microvesicle leaves inflation area by one-way slabs, enters collecting region 86 (Fig. 5), and collecting region is to be positioned at the zone feed distributor below, the inflation area top.Because the diameter of bubble is little, mobile in collecting region is basic immobilized, thereby makes algae suspension and microvesicle obtain effective counter current contact.The salt solution that does not contain algae flows out as bottoms stream by the aperture on the one-way slabs.Bubble and algae aggregation rise to froth zone from collecting region, accumulate at froth zone.Washing lotion can join in the foam, to separate the hydrophilic particulate that is pulled away from the algae biotron.Be rich in carotenoid foam overflow tower, enter the collection washing machine, and leave washing machine as enriched material.

Microvesicle generators is made up of the winglet sheet that many series connection are provided with, and the fluidic direction is often changed.This design is similar in appearance to static mixer.Liquid passes through mixing tank with extremely high speed pumping, and required volumetrical gas is introduced into fluid pipeline before entering mixing tank.Fluidic shearing force dispersed gas body forms microvesicle.By this technology, can produce the microbubble suspensions (by volume calculation) that contains the above gas of 50 volumes.G. other floatation equipment

Except above-described specific machinery and air-flow floatation equipment, also have many equipment that are suitable for principle of the present invention not mention.These equipment are mainly different in detail, different geometrical shapies is arranged or adopt different bubbles and the algae way of contact, the mode that is separated or bubble generation mode as them.

No matter select what kind of absorption bubble isolation technique, thick-layer to filter and the microfiltration combination, algae suspension should be concentrated into an optimum concn, makes leaching process the best, and this depends on many factors, comprises economic factors.Because the big container that need provide solvent to contact with suspension, or owing to need to use a large amount of solvents, it is infeasible extracting composition from the algae suspension of lower concentration.Thick-layer filters, the absorption bubble separates and microfiltration can be used in combination respectively, or is used in combination with other algae suspension dehydration technique, to obtain to extract required concentration and benefit.E. favourable pneumatic flotation circulation

For reclaiming carotenoid, using a purpose of absorption bubble separation method is the foam that produces the carotenoid that contains maximum concentration, especially uses froth-flotation method.In flotation flowsheet, any floatation equipment all can use in any position.But above-mentioned froth-flotation method there is no need to have the effect that is equal to aspect the ability of the concentrated carotenoid of foam.A favourable pneumatic flotation flow process that is used for algae such as Dunaliella salina dehydration is described below with reference to Figure 11.The Jameson groove is as coarse classifier 230 and one-level preparator 232.The MSTLFLO tower is connected in series with Jameson groove preparator 232 as secondary preparator 234.Jameson groove and MSTLFLO tower can be installed on above-mentioned raft, trailer or other transportation means, to be easy to obtain the algae feedstream.

As shown in figure 11, saliferous is given birth to the salt solution feedstream 236 of Dunaliella salina by its source acquisition.The source comprises: the Great Salt lake of natural lake such as Utah, intensive pond or extensive pond.Feedstream can be by above-mentioned impeller pump as movably floating pump acquisition.Raw material is transported to the feed(raw material)inlet 240 of Jameson groove coarse classifier 230 by pump 238.

Before raw material entered Jameson groove coarse classifier, algae can be broken or break by other above-mentioned mechanism in the pump circulation.

Foam is collected in collecting washing machine 248, then or break and conventional pumping, perhaps by foam pump 250, is pumped to storagetank 252, is used for Jameson groove preparator 232 as the feedstream 253 that is rich in carotenoid.Bottoms stream 254 can be dropped or return its place, source, or handles by the content of describing during above V.C. summarizes.

The feedstream that is rich in carotenoid 253 of Jameson groove preparator is pumped to feed(raw material)inlet 256, and separates in the Jameson groove.Usually produce than coarse classifier 230 exsiccant foam more.The liquid stream 258 that is rich in carotenoid is stored in the raw material tank 260, as the raw material of MSTLFLO tower preparator 234.Bottoms stream 262 is similar to the bottoms stream of coarse classifier and handles.

The feedstream 264 that is rich in carotenoid is pumped to the feed(raw material)inlet 266 of MSTLFLO tower preparator 234 from storagetank 260, and is separated then, as mentioned above.Produce the foam of the further enrichment carotenoid of exsiccant again, collect foam, be stored in storagetank 268, further handle again.Further handle and comprise: microfiltration is dewatered further to make algae, or adopts any method that describes below to extract.

As shown in figure 11, being right after is high density gas extraction units 272 in above-mentioned microfilter 270 back.Compare with the concentration of carotenoid in the pneumatic flotation flow process, microfiltration makes the concentration of carotenoid be the order of magnitude to be increased, and can reach about 20 in debris 274, and 000ppm is suitable for the extraction of high density gas.Penetrating fluid 276 is an effluent brine solution, and the situation according to containing chemical additive (even having also seldom) in the effluent brine abandons or return former lake or pond.

Debris 274 is pumped to high density gas as feedstream and extracts equipment 272.High density gas is carbonic acid gas in this case, adds with the direction with the feedstream counter current, and this part content is conventionally known to one of skill in the art, also will extract in the relevant content with high density gas hereinafter to further describe.The bottoms stream 278 that high density gas is extracted equipment is residual solution, is the waste liquid that does not contain carotenoid, extracts the content of other cellular material after can being dropped or extracting by carotenoid among the VI hereinafter again and further handles.

The extract 280 that high density gas is extracted equipment overflows tower, expands to enter separator 282 to separate mixing carotenoid from high density gas.Mix carotenoid and flow out separator as bottoms stream 284.High density gas 286 flows out separator from the separator top, be recycled to the bottom that high density gas is extracted equipment by compressor.Mixing carotenoid can further handle by the method for following recovery certain kinds carotene.VI. from spissated algae suspension, reclaim selected composition

See the step 30 and 32 of Fig. 1, by using the extracting method of all kinds of SOLVENTS, carotenoid can be recovered from spissated algae suspension.Extracting method can be selected from: liquid/liquid extracts; Solid-liquid extracts, and is also referred to as leaching process; Gu liquid/liquid/extraction is that a kind of three-phase extracts, wherein immiscible two-phase forms in solid matter and above-mentioned high density gas is extracted.

Under the concentration conditions greater than about 100ppm, the immiscible organic solvent of any and water all can be used for extracting carotenoid from Dunaliella salina salt aqeous suspension.Organic solvent should can change the physics and the chemical property of carotenoid at least sharply.As long as produce two or more immiscible phase systems, solvent can be selected from: synthetic or natural flavoring, edible oil, petroleum chemistry solvent, high density gas and their combination.Because following a variety of causes, in these solvents, other solvent of some solvent ratio is more feasible, still, and the effect that unnecessary generation is identical.

The common viscosity of petroleum chemistry solvent is low, and the solute molecule diffusibility is strong.Carotenoid usually in the petroleum chemistry solvent solubleness higher, it is feasible carrying out concentration extraction.The petroleum chemistry solvent comprises: aliphatic hydrocarbon, as hexane, pentane, octane, sherwood oil, hexanaphthene, methylene dichloride, methyl alcohol, ethanol and other lower boiling alcohol; Arene such as benzene and toluene; And many other unlisted petroleum chemistry solvents.If desired, use petroleum chemistry solvent also capable of being combined.

Yet, should be realized that for the extraction of the carotenoid that is used as nutritional additive, the petroleum chemistry solvent is considered to undesirable solvent usually.Though at least to a certain extent, solvent residues can be removed by chromatography.But for many people, the petroleum derivation compound is used for processing nutritional additive and at nutritional additive any petroleum residues is arranged all is not satisfied.

From the angle of trophology, edible oil is more preferred than petroleum chemistry solvent.Edible oil derives from animals and plants, as fish oil.The food plant Oil solvent comprises Semen Maydis oil, sweet oil, soybean oil, Thistle oil, sunflower oil and a lot of other oil.If desired, use edible oil also capable of being combined.

Yet with petroleum chemistry solvent phase ratio, the common viscosity of edible oil is higher, and the solute molecule diffusibility is lower.The carotenoid solubleness in edible oil usually is limited, does not change the physics of carotenoid and the step of chemical property, as adopts overheated step, then is difficult to obtain spissated extract.

Synthetic and natural flavoring more caters to the need than petroleum chemistry solvent and edible oil usually.Natural flavoring is more suitable for the extraction of nutritional additive.From the angle of nutritional additive, by Flavorand Extract Maufacturers Association, or FEMA is divided into " it has been generally acknowledged that safety " level, or the spices of GRAS level does not have the shortcoming of petroleum chemistry solvent.With petroleum chemistry solvent phase ratio, residual perfume solvent acceptable normally in nutritional additive, and reduced follow-up purifying and cost recovery.Can select to use spices aspect boiling point, viscosity and molecular diffusion performance and like the petroleum chemistry solvent phase.

Spices suitable among the present invention comprises: carboxylic acid methyl-, ethyl-, propyl group-, butyl-, isobutyl--, phenyl-and octyl group-ester class, as acetic ester, ethanoate, propionic ester, butyric ester, capronate, octanoate, heptanoate, octanoate, decylate, laurate and isopentanoate.Other spices example includes but are not limited to: phenyl aldehyde, other formaldehydes, Limonene and other terpene.If desired, use spices also capable of being combined.

Method flow shown in Figure 12 is a typical extraction step.In initial solvent extraction step 300, spissated algae suspension contacts with solvent.Carotenoid is transferred to the second fluid phase, i.e. extract phase or solvent phase from salt solution.As the described leaching process of step 302, form two-phase and waste liquid layer.Form the waste liquid layer of algae residue between thick extract phase and residue liquid phase, contain carotenoid and solvent in the wherein thick extract phase, the residue liquid phase is mainly the carotenoid of salt solution and trace.The algae residue contains chlorophyll, glycerine, phosphatide and protein usually, can abandon, also can be according to step 310, and further processing is to reclaim these compositions.

Extraction can be carried out in batches, also can carry out continuously.The batch-wise leaching process is proved to be feasible.Organic phase and water fully stir, and all carotenoid all is extracted enters in the organic phase.Stop to stir.Dispersed system leaves standstill, and forms three different zones: residue liquid layer, extraction liquid layer and waste liquid layer.Separate these liquid layers by decant carefully, further to process by following step.

The various extraction equipment that are used for extracting continuously comprise: single-stage, multistage mixing machine and settling vessel; Centrifugal extractor is as by being positioned at Pittsfield, the product that the Robatel of Massachusetts makes and by Baker Perkins of Saginaw, the Podbelniak that Michigan makes; Extraction column such as Karr tower, York-Scheibel tower and rotating disc contactor, by being positioned at Parasippany, the Glitsch Technology Corporation of New York makes, by being positioned at Allschwil, Kuhni tower that the Kuhni of Switzerland makes and filling perforated plate tower.

Continuous extraction method adopts settling methods.Under centrifuge field or gravity field, can be separated, the cost of gravity settling is lower.Setting accelerator is added into wherein usually, to help decant.According to the type of aquatic breed, before being recovered into bio-reactor or returning the pond, any added solvent that residual solution can further be condensed and may be brought into to reclaim.Gu setting accelerator, liquid/liquid/centrifugal, flotation cell and liquid/liquid cyclonic separator also can be used for reclaiming solvent from salt solution, salt solution also can return floatation equipment and purify.

This extracting method can be used for extracting carotenoid from salt solution, salt solution can be according to existing enrichment step, after concentrating as above-mentioned enrichment step, also untreated, the method for extracting from untreated salt solution promptly is a collecting method.In the later case, from decanting vessel, reclaim the ratio that solvent can increase solvent and raw material in the mixing tank.

If desired, water can carry out pre-treatment so that contained chlorophyll is minimum in the organic phase.Before extraction, the water that contains biomass can carry out alkaline purification, as NaOH, with saponification chlorophyll, stops it to be extracted with carotenoid and enters organic phase.In addition, also can will contain the aqueous phase as acidified of biomass, enter organic phase to stop chlorophyll to be extracted.

Before one or more dehydrating steps, solvent is disperseed in algae suspension.In this case, solvent is extracted after pretreated by pre-dispersed and raw material again.For example, before initial absorption bubble separated, solvent can be by pre-dispersed in algae suspension.A. the purifying of composition with separate

The crude extract of carotenoid separates with residual solution with the waste liquid layer as stated above.Be rich in the crude extract of carotenoid and be rich in glycerine and proteinic waste liquid layer all can be handled, to reclaim preparation and purifying valuable ingredients.Callable compound comprises: all-trans β-Hu Luobusu, 9-cis β-Hu Luobusu, alpha-carotene, zeaxanthin, kryptoxanthin, xenthophylls, glycerine, protein and other composition.The various technology of crude extract purifying are known in those skilled in the art.

According to step 312, by one or more technology, as by evaporating solvents such as flash distillation, distillation, wiped film vaporization, short-path distillation and molecular distillations, crude extract can be further concentrated.Select suitable solvent, can be so that this enrichment step carry out at low temperatures, carotenoid will not be degraded or isomerization again.The working method of preferred crude extract depends on the product of required acquisition.

Can directly from enrichment step 312, collect carotenoid, also can by solvent exchange process carotenoid be scattered in the edible oil again according to enrichment step 314 as the solid phase.Blended carotenoid product is 316 purifying set by step as required.Before evaporation, can also can be after extracting before extracting, edible oil mixes with spices, makes the spices of desired amount be evaporated, and stays carotenoid in edible oil.Edible oil can be animal oil or mixed vegetable oil, as sweet oil, canola oil, peanut oil, soybean oil, Thistle oil, sunflower oil, plam oil, Semen Maydis oil and composition thereof.By this method, can not need expensive edible oil molecular distillation step basically, the molecular distillation step is mainly used in and further concentrates carotenoid suspension.B. β-Hu Luobusu and other carotenoid

The edible oil suspension of mixing carotenoid can be used as nutritional additive, food colorant and the food fortifier of human body and sells on market.In addition, the product of the different concns ratio of various types of carotene can be by separating step production subsequently, the description that sees below.Crude extract can carry out purifying by chromatography, from recyclable carotenoid of its fraction crystallization and solvent.Other processing comprises: crystallization, supercritical fluid chromatography, reverse-phase chromatography and high performance liquid chromatography (HPLC).

Many products can obtain by these cell processing.Supercritical fluid chromatography is separated all trans alpha-carotenes, alpha-carotene cis-isomeride, all trans β-Hu Luobusus, β-Hu Luobusu cis-isomeride.Reverse-phase chromatography can be used for separating xenthophylls, zeaxanthin, beta-cryptoxanthin, myoxanthin, Lyeopene, alpha-carotene and β-Hu Luobusu.HPLC can be used for separating β-Hu Luobusu, myoxanthin, canthaxanthin, fucoxanthine, astacin, 13-15-two-cis-β-Hu Luobusu, 15-cis-β-Hu Luobusu, β-Hu Luobusu, 9-cis-β-Hu Luobusu and 13-cis-β-Hu Luobusu.HPLC is used in combination with supercritical fluid chromatography and can be used for separating 13-13 '-two-cis-β-Hu Luobusu, 9,13,13 '-three-cis-β-Hu Luobusu, 9-13 '-two-cis-β-Hu Luobusu, 15-cis-β-Hu Luobusu, 9-13-two-cis-β-Hu Luobusu, 13-cis-β-Hu Luobusu, 9-9 '-two-cis-β-Hu Luobusu, all trans β-Hu Luobusus and 9-cis-β-Hu Luobusu.

Highly purified β-Hu Luobusu extract is made up of with the various trans-isomer(ide)s that are less than 50% (weight) the 9-cis-isomeride of 40% (weight) at least, and it can be by preparing at activatory alumina column separating isomerism body.The extract that is rich in 9-cis-β-Hu Luobusu is made up of the 9-cis-isomeride of 75% (weight) at least, can be by the crystallization in non-polar solvent of all trans-isomer(ide)s is prepared.Highly purified β-Hu Luobusu extract can be by removing solvent from crude extract, and carotenoid is suspended in minimum non-polar solvent be prepared again.This solvent is selected from: ethane, hexane, pentane, octane and sherwood oil.Then, nonpolar extract is collected fraction by activatory oxide pillars and tower.The fraction that at first will contain orange/red carotenoid primary spectrum band (main band) dilutes, collect fraction, the vaporising under vacuum solvent, promptly obtain highly purified natural β-Hu Luobusu product, usually form by various trans, 40%9-cis, 3% other β-Hu Luobusu isomer, 5% alpha-carotene and 2% other carotenoid of 50%.Faint yellow carotenoid dilution with after the β-Hu Luobusu fraction still comprises some β-Hu Luobusus.

Regularly washing tower does not have diluted any polarity carotenoid, lipid and chlorophyll to remove.Highly purified natural 9-cis-β-Hu Luobusu obtains through the following steps: highly purified natural beta-carotin is dissolved in the minimum non-polar solvent, be warming up to 40-50 ℃ of dissolving β-Hu Luobusu, the cooling solvent to-20 ℃ with all trans-isomer(ide)s of preferential crystallization, separate solid phase and liquid phase.The crystalline step can repeat, to improve the purity of crystal and upper solution.Solvent in the evaporative removal upper solution, the prepared product of 9-cis-isomeride is rich in acquisition, and its concentration is at least 75% (weight).C. product and application

The β-Hu Luobusu that obtains by method of the present invention can be prepared into the product of any kind for selling with other carotenoid.Spray-dired Dunaliella salina powder can add in the animal-feed.Product can be the carotenoid oil suspension, carotenoid microcapsules of various concentration, water dispersible natural mixed carotenoid powder.β-Hu Luobusu also can be purified and the form sale to be rich in the 9-cis-isomeride or to be rich in all trans-isomer(ide)s.Other carotenoid that obtains by the inventive method also can be purified and sell with the form of product.D. glycerine, protein and other composition

The algae residue can be dropped or further process according to step 310, to reclaim other valuable ingredients in the algae, as glycerine, chlorophyll and protein.

The waste liquid layer can contact with ethanol, reclaims glycerine.Ethanol evaporation then, the glycerin residues of acquisition can be carried out purifying by distillation.Glycerine can be extracted, decolours and distill, to obtain practical product for selling.Behind the glycerin extraction, remaining cellular material rich in proteins after the drying, obtains algae albumen, can be used as animal-feed.Cellular material is before drying, and the used water washing is to remove residual salinity.VII. embodiment

The following examples are for example understood several partial contents of the present invention, but do not limit the present invention.According to the specific content of embodiment the present invention pointed, the structure of embodiment is organized by subhead.But, should be realized that the soluble explanation of embodiment several partial contents of the present invention under specific title.These titles should not be considered to that embodiment monopolizes under the different title.A. cell rupture in pump circulation

According to Fig. 2, as described below, the size of pressure drop and the quantity of the Dunaliella salina by pressure drop can be estimated the degree of breaking of Dunaliella salina.The salt solution that contains Dunaliella salina is transported to Jameson groove 36 by pump 38 pond 34 from the Great Salt lake, and wherein pump is Grundfos SeriesC stage chamber pump CR30-80U.Salt solution is circulation repeatedly in the blowback road, with the algae of breaking.By-pass flow 46 defines circular flow.Leak conduit 48 salt solution that is used for releasing returns the pond.By-pass flow flow and discharge flow are controlled by valve 50 and 52 respectively.As required, the recovery percent in the circulation of required pump can provide by the change of flow velocity.By throttling valve 42, pressure drop can transfer to required value.

Under each blowdown presssure, by the master cylinder discharge speed Q of pipeline 40 ₁Measure as follows: valve-off 50, measure earial drainage speed Q by pipeline 48 ₄With the input speed Q of Jameson groove at 44 places ₅It is that 55 gallons bucket is determined the required time that the earial drainage flow velocity can be filled capacity by measurement.The charging flow velocity of Jameson groove can be by following Equation for Calculating:

&upsi; = \sqrt{\frac{2 Δp}{ρ}}

Q_{5} = C_{0} \frac{{πd}_{0}^{2}}{4} &upsi;

Wherein υ is a throttle orifice speed, and Δ p is that ρ is a fluid density, C in the approximation of the feed pressure of pressure detection meter 54 places mensuration ₀Being the throttle orifice coefficient, is 0.61, d ₀Being the throttle orifice diameter, is 0.3125 inch.

Under specific blowdown presssure, master cylinder discharge speed Q ₁Calculate according to the mass conservation.When valve 50 was pent, the by-pass flow amount was zero, and following equation is set up.

Q ₁＝Q ₄+Q ₅

Valve 50 opens so that salt solution circulation time in the blowback road, and the by-pass flow flow velocity is according to following Equation for Calculating:

Q ₂=Q ₁-(Q ₄+ Q ₅) Q wherein ₄And Q ₅Adopt above-mentioned method to measure Q ₂It is flow velocity by pipeline 46.

Pump circulation recovery percent R calculates by following formula:

R＝(Q ₂/Q ₅)·100％

Pressure drop (Δ p) by throttling valve 42 forms has promoted breaking of cell, can calculate by following formula:

Δ P _t=p ₁-p ₂P wherein ₁And p ₂Be respectively pressure indicator 56 and 58 measured force value.

In present method, the algae percentage that breaks can calculate by cell counting.Measurement pumps into every milliliter of viable count Q of the feedstream of pipeline 60 ₀Every milliliter of viable count Q with the bottoms stream 50 of Jameson groove ₇The algae percentage ratio F that breaks calculates by following formula:

F=(1-CC _t/ CC _f) 100% CC wherein _tAnd CC _fIt is respectively the cell count in feedstream and the Jameson bottom land thing sample.Cell count is meant cell numbers all in every mL of saline.B. thick-layer filters

Mixed brine suspension is 30 seconds in organizing beating crusher, and the Dunaliella salina frustule is broken.With 1 liter disruptive Dunaliella salina suspension salt-water liquid filter by the tower that is filled with filtration medium.The internal diameter of tower is 30 millimeters, and length is 80 millimeters.Various filtration mediums are as shown in table 1.

The filtration medium type that table 1 uses

The type of medium	The size of medium	The medium amount of using in the test
The type of medium	The size of medium	The medium amount of using in the test	Quartz sand	0.25-.035 millimeter	43 grams
Hard coal	0.85-0.95 millimeter	23 grams	Quartz sand	0.25-.035 millimeter	43 grams
Hard coal	0.85-0.95 millimeter	23 grams	Glass wool		2.2 gram
Blending agent	Sand, hard coal and garnet mixture		Glass wool		2.2 gram

After filtering end, medium uses distilled water wash to reclaim cellular material.This water solvent extraction, gained solution carries out the carotenoid analysis.Medium is used solvent wash more then, and gained solution also carries out the carotenoid analysis.Feedstream before filtering and filtrate is sampling analysis carotenoid also, is trapped in carotenoid percentage in the medium with measurement.Embodiment 1-7 the results are shown in table 2.

Table 2 thick-layer filtering result

Embodiment number	Media type	Be trapped in the carotenoid % in the medium	Washing water (milliliter)	The carotenoid that reclaims in the washing water (milligram)	Solvent washing lotion (milliliter)	The carotenoid that reclaims in the solvent (milligram)	Solvent
Embodiment number	Media type	Be trapped in the carotenoid % in the medium	Washing water (milliliter)		Solvent washing lotion (milliliter)	The carotenoid that reclaims in the solvent (milligram)	Solvent	??1	Quartzy	????70.4％	??-	????-	????-	????-	-
??2	Quartzy	????72.2％	??50	????0.94	????30	????0.38	Limonene	??1	Quartzy	????70.4％	??-	????-	????-	????-	-
??2	Quartzy	????72.2％	??50	????0.94	????30	????0.38	Limonene	??3	Garnet	????17.9％	??100	????0.16	????30	????0.02	Limonene
??4	Quartzy	????66.7％	??200	????0.37	????60	????0.03	Limonene	??3	Garnet	????17.9％	??100	????0.16	????30	????0.02	Limonene
??4	Quartzy	????66.7％	??200	????0.37	????60	????0.03	Limonene	??5	Glass wool	????79.9％	??150	????0.88	????75	????0.36	Limonene
??6	Blending agent	????30.8％	??-	????-	????-	????-	Limonene	??5	Glass wool	????79.9％	??150	????0.88	????75	????0.36	Limonene
??6	Blending agent	????30.8％	??-	????-	????-	????-	Limonene	??7	Quartzy	????83.5％	??100	????0.82	????24	????0.04	Heptane

When adopting the thick-layer filtration to carry out the algae dehydration, ruptured cell will illustrate in the following embodiments to the influence of this process.Except that cell before filtration did not break, other step was identical with the step that embodiment 1-7 describes.Thick-layer adopts the quartz sand of 0.25 to 0.35 millimeter of particle diameter as filtration medium.Salt solution carries out following processing before filtration: algae suspension was mixed 1 minute in not aeriferous Denver D-12 mechanical flotation cell with the TRITONX-100 nonionogenic tenside.The tensio-active agent volumetric concentration is 25ppm.The rate of recovery that draws algae according to carotenoid concentration is 25%.C. microfiltration

The equipment of microfiltration as shown in Figure 3.The algae concentrated solution that derives from bubble cell is added in the raw material tank 62, be pumped to cross-flow microfiltration device 66 by pump 64 (7.5 horsepowers, 102 amperes, 460 volts are moved down) again.The cross-flow microfiltration device contains the zirconium oxide film of 1.4 microns in specified aperture, 2.15 square inches of surface-area.This film is by being positioned at Whittier, and the U.S.Filter of California provides.The microfiltration cell cross-section is a hexagon, has 19 flow passages.4 millimeters of each channel diameters, long 80 centimetres.Heat exchanger 68 is used for cooling off feedstream before entering strainer.Pressure drop by film is measured by pressure indicator 74 and 76.

Stagnant liquid 70 returns raw material tank, to return strainer.Abandon filtrate 69.Under different time, the quality of record filtrate.Circulation N calculates according to following formula:

N = \frac{M_{2} - M_{1}}{A (t_{5} - t_{1})}

Wherein A is the cross-sectional area of the negotiable liquid of filter, M ₂And M ₁Be respectively time t ₂And t ₁The time amount of filtrate.The flow velocity of raw material is measured according under meter 78.The temperature thermometer measure.Collecting retentate and filtrate sample, analysis classes carotene.

Suspension continuous filtration 6 hours.Reclaim about 150 pounds filtrate.The curve of circulation and time as shown in Figure 4.Observe after the first effluent of cross-flow microfiltration, in whole operation process, under pressure drop did not obviously increase, circulation kept 115kg/hr/m substantially ²Constant.This result is astonishing, thinks that the algae after breaking has the characteristic of gel, can very fast obstruction filter membrane.More surprisingly, in filtrate, do not detect carotenoid.Because the particle diameter of carotenoid is very little,, think to have tangible carotenoid loss less than 0.1 micron.

Diafiltration is used for reducing the salt concn of stagnant liquid.Clear water joins in the raw material tank 62.According to the salt concn of final stagnant liquid, whether decision needs to increase is filtered and water-reducible step.After 6 hours filtrations finish, with the clear water dilution stagnant liquid of equivalent, and filtered 13 minutes, make volume identical with original volume.After filtering in 13 minutes, add the clear water dilution of equivalent again, carry out the diafiltration second time, filtered 13 minutes, make volume identical with original volume.The circulation that these percolation tests are measured as shown in Figure 4.D. pneumatic flotation 1. mechanical foam flotation

The salt solution that the contains Dunaliella salina suspension small-sized froth flotation equipment of Denver D-12 of packing into.Froth flotation equipment can suck an amount of air by the speed of impeller through design.The diameter that use has 8 leaves is 2.75 inches a impeller.Except that embodiment 20, remaining embodiment all adopts the tempering tank of 2000g, and embodiment 20 adopts the tempering tank of 4000g.Collection liquid sample under the different time, the rate of recovery of carotenoid in measurement floatation kinetics and the salt solution.After running finishes each time, collect spissated foam, under the 456nm wavelength, measure carotenoid by the UV-VIS spectrograph.

The variable of test comprises: initial classes concentration of carotene and dosage of surfactant in wheel speed, gas flow rate, groove volume, the salt solution.Gas flow rate changes according to the compressed-air actuated amount of stir shaft.According to uncracked algae, the concentrated foam in disruptive algae and the previous flotation is measured the rate of recovery.Embodiment 8-10

The Dunaliella salina frustule mixes in historrhexis's machine and broke in 30 seconds.2000 milliliters of suspension saline solutions that contain ruptured cell flotation cell of packing into mixed 10 to 20 minutes.The carotenoid rate of recovery after 10 minutes is summarized in table 3.Table 3 the disruptive algae after flotation in 10 minutes wheel speed to the influence of the carotenoid rate of recovery

Embodiment number	Wheel speed (rpm)	The carotenoid rate of recovery (%)
Embodiment number	Wheel speed (rpm)	The carotenoid rate of recovery (%)	????8	????1300	????86
????9	????1500	????87	????8	????1300	????86
????9	????1500	????87	????10	????1700	????86

Embodiment 11-16

2000 mL of saline that the contain Dunaliella salina suspension flotation cell of packing into mixed 35 minutes.The carotenoid rate of recovery after 10 minutes is summarized in table 4.Table 4 the disruptive algae after flotation in 10 minutes impeller commentaries on classics degree to the influence of the carotenoid rate of recovery

Embodiment number	Wheel speed (rpm)	The carotenoid rate of recovery (%)
Embodiment number	Wheel speed (rpm)	The carotenoid rate of recovery (%)	????11	????1300	????51
????12	????1500	????70	????11	????1300	????51
????12	????1500	????70	????13	????1700	????79
????14	????1700	????72	????13	????1700	????79
????14	????1700	????72	????15	????2000	????96
????16	????2300	????99	????15	????2000	????96

Embodiment 17-20

The salt solution that the contains Dunaliella salina suspension flotation cell of packing into mixed 35 minutes under the 1500rpm rotating speed.The groove volume is summarized in table 5 to the influence of the carotenoid rate of recovery.10 minutes pit volumes of table 5 are to the influence of the carotenoid rate of recovery in the Dunaliella salina

Embodiment number	Groove volume (milliliter)	The carotenoid rate of recovery (%)
Embodiment number	Groove volume (milliliter)	The carotenoid rate of recovery (%)	????17	????2000	????79
????18	????2400	????69	????17	????2000	????79
????18	????2400	????69	????19	????2800	????69
????20	????4000	????68	????19	????2800	????69

Embodiment 21-25

2000 mL of saline that the contain Dunaliella salina suspension flotation cell of packing into mixed 10 minutes.Gas flow is summarized in table 6 to the influence of the carotenoid rate of recovery after 10 minutes.Table 6 gas flow and wheel speed are to the influence of the carotenoid rate of recovery in the uncracked Dunaliella salina

Embodiment number	Gas flow rate	Wheel speed (rpm)	The carotenoid rate of recovery (%)
Embodiment number	Gas flow rate	Wheel speed (rpm)	The carotenoid rate of recovery (%)	????21	??43CFH	????2550	????98
????22	??50CFH	????2000	????92	????21	??43CFH	????2550	????98
????22	??50CFH	????2000	????92	????23	??40CFH	????2000	????94
????24	??30CFH	????2000	????92	????23	??40CFH	????2000	????94
????24	??30CFH	????2000	????92	????25	??40CFH	????1500	????84

Embodiment 26,27 and 28

2000 milliliters of salt solution that contain basic, normal, high concentration Dunaliella salina are respectively charged into flotation cell, mix 10 minutes.Cell concn is summarized in table 7 to the influence of the carotenoid rate of recovery.

Table 7 after 10 minutes carotenoid concentration to the influence of the carotenoid rate of recovery

Embodiment number	Carotenoid concentration	The carotenoid rate of recovery (%)
Embodiment number	Carotenoid concentration	The carotenoid rate of recovery (%)	????26	0.00032 mg/ml salt solution (～1800 cells/ml)	????90％
????27	0.002 mg/ml salt solution	????70％	????26	0.00032 mg/ml salt solution (～1800 cells/ml)	????90％
????27	0.002 mg/ml salt solution	????70％	????28	0.125 mg/ml salt solution (～1.3M cells/ml)	????66％

Embodiment 29 and 30

2000 milliliters of suspension saline solutions that contain Dunaliella salina flotation cell of packing into.Triton X-100 joins in the salt solution, and solution is at the 1500rpm rotating speed, and no air conditions mixed 1 minute down.Open air door then, suspension and air mixed 20 minutes.Measure the carotenoid rate of recovery after 10 minutes, the results are summarized in table 8.

10 minutes rear surface surfactant concentrations of table 8 are to the influence of the carotenoid rate of recovery

Embodiment number	Surfactant concentration (ppm)	The carotenoid rate of recovery (%)
Embodiment number	Surfactant concentration (ppm)	The carotenoid rate of recovery (%)	????29	????25	????10％
????30	????100	????25％	????29	????25	????10％

Embodiment 31 and 32

2000 milliliters of concentrated foams that derive from flotation cell reinstall flotation cell, mix 35 minutes.Measure the carotenoid rate of recovery after 10 minutes, the results are summarized in table 9.Table 9 after 10 minutes wheel speed to influence from the carotenoid rate of recovery in the concentrated foam of last flotation

Embodiment number	Wheel speed (rpm)	The carotenoid rate of recovery (%)
Embodiment number	Wheel speed (rpm)	The carotenoid rate of recovery (%)	????31	????1500	????94％
????32	????2000	????85％	????31	????1500	????94％

Embodiment 33

On the rotor and stator structure in Denver DR-8 four each groove of scouring machine tool floatation equipment, all be equipped with the Rushton turibine rotor of 8 flat blades.This unit continuous feed concentration is the algae suspension of 7 grams per milliliters.The ratio of groove diameter and impeller diameter is 2.1.The ratio of groove height and groove diameter is 0.84.The submergence of rotor and the ratio of liquid depth are 0.75.4 all impellers, its impeller tip speed is all constant in 1790 inch per minute clocks.The liquid hold-up time is 11 minutes.J _gValue is 4.0 cels.The ratio of gas and raw material is 16.4.The solid percentage is 0.02% (not calculating gas) in the foam.The carotenoid rate of recovery is 78%.2. air-flow pneumatic flotation a.Jameson groove

The suspension saline solution that contains Dunaliella salina suspension is packed into and is handled in the mechanical pretreatment equipment, with ruptured cell, handles in the Jameson groove then.The downspout conductor diameter of Jameson groove and the ratio of throttle orifice diameter are 8.6, and upper reaches pipe diameter and downspout conductor diameter L ratio are 5.The J of groove _gValue is 0.44 cel.Jet velocity is 21.5 meter per seconds.The downspout conductor surface velocity is 0.20 meter per second.The downspout conductor liquid hold-up time is 15.1 seconds.The ratio of air and raw material is 0.52.The carotenoid rate of recovery average out to 58.8% of this process.The solid percentage is 0.02% (not calculating gas) in the foam.Embodiment 35

The foam that produces in the test that embodiment 34 describes is collected, and handles with the Jameson groove of the geometrical shape with embodiment 34 descriptions, further to concentrate carotenoid.The J of groove _gValue is 0.27 cel.Jet velocity is 10.6 meter per seconds.The downspout conductor surface velocity is 0.13 meter per second.The downspout conductor liquid hold-up time is 23.2 seconds.The ratio of air and raw material is 0.49.The carotenoid rate of recovery average out to 89.7% of this process.The solid percentage is 0.5% (not calculating gas) in the foam.Embodiment 36

The salt solution that contains Dunaliella salina suspension is not carrying out under any machinery or the Chemical Pretreatment situation, handles with the Jameson groove of the geometrical shape with embodiment 34 descriptions.The J of groove _gValue is 0.65 cel.Jet velocity is 46.1 meter per seconds.The downspout conductor surface velocity is 0.175 meter per second.The downspout conductor liquid hold-up time is 17.5 seconds.The ratio of air and raw material is 0.88.The carotenoid rate of recovery average out to 52.8% of this process.The solid percentage is 0.02% (not calculating gas) in the foam.Embodiment 37

The foam that produces in the test that embodiment 34 describes is collected, and handles with the Jameson groove of the geometrical shape with embodiment 34 descriptions, further to concentrate carotenoid.The Jg value of groove is 0.29 cel.Jet velocity is 11.9 meter per seconds.The downspout conductor surface velocity is 0.14 meter per second.The downspout conductor liquid hold-up time is 21.7 seconds.Feed pressure is 22 pounds/square inch.The ratio of air and raw material is 0.49.The carotenoid rate of recovery average out to 68% of this process.The solid percentage is 8.3% (not calculating gas) in the foam.Embodiment 38

The salt solution that contains Dunaliella salina suspension is handled with froth flotation equipment.Foam breaks basically, enters in the Jameson groove with geometrical shape that embodiment 34 describes with 65 liters/minute flow velocity continuously.The gas flow rate that enters groove is 1.1 standard cubic foots/minute (SCFM).Move 1 hour, the rate of recovery average out to 89.7% of carotenoid in the foam.Embodiment 39

The salt solution that contains Dunaliella salina suspension is handled with froth flotation equipment.Collect bottoms stream, enter in the Jameson groove with geometrical shape that embodiment 34 describes with 62 liters/minute flow velocity continuously.The gas flow rate that enters groove is 1.7 standard cubic foots/minute (SCFM).The rate of recovery average out to 79% of carotenoid in the foam.B. multi-stage circulating-flow foam flotation tower (MSTLFLO)

The MSTLFLO tower is used for the following examples 40 to 47, and its diameter is that 4 inches, height are 125 inches, 3 drainage tubes are housed.The depth-width ratio of drainage tube is 12.2.The ratio of drainage tube diameter and tower diameter is 2.The ratio of rinse bath diameter and tower diameter is 2.Do not add pore forming material.Brinish pH value is 6-7.The sintering metal atomizer is used for injection air and enters in the tower.The diameter of atomizer is 10 microns of 1 inches, long 6 inches, aperture.Atomizer is installed in the bottom of a bottom drainage tube.Feed distributor is installed in 6 inches places, drainage tube top.Embodiment 40

Fill the salt solution that contains carotenoid in the MSTLFLO tower.Air velocity and raw material flow rate are respectively 1.5SCFH and 3.4 liters/minute, make that the ratio of air and raw material is 0.21.Tower moves in a continuous manner, and raw material, foam and bottoms stream sample are gathered with 5 minutes interval.J _gValue is 0.15 cel.The liquid hold-up time is 5.2 minutes.The solid percentage is about 6% (not calculating gas) in the foam.The rate of recovery of carotenoid is 78%.Embodiment 41

Fill the salt solution that contains carotenoid in the MSTLFLO tower.Air velocity and raw material flow rate are respectively 1.5SCFH and 6 liters/minute, make that the ratio of air and raw material is 0.12.Tower moves in a continuous manner, and raw material, foam and bottoms stream sample are gathered when 5 minutes gaps.J _gValue is 0.15 cel.The liquid hold-up time is 3.2 minutes.The solid percentage is about 17% (not calculating gas) in the foam.The rate of recovery of carotenoid is 76%.Embodiment 42

Fill the salt solution that contains carotenoid in the MSTLFLO tower.Air velocity is 3SCFH.Tower moves in the mode of batch treatment, and raw material, foam and bottoms stream sample are gathered when finishing a flotation (20 minutes).J _gValue is 0.29 cel.The solid percentage is about 11% (not calculating gas) in the foam.The rate of recovery of carotenoid is 83%.Embodiment 43

The saliferous of packing in the embodiment 41 described MSTLFLO towers is given birth to the salt solution of Dunaliella salina.This salt solution is that previous floatation equipment was handled.The gas flow rate that enters in the tower is 3-4SCFH.After 25 minutes, the rate of recovery of carotenoid is more than 87% in the foam.Embodiment 44

The salt solution that contains Dunaliella salina suspension is handled with froth flotation equipment.Foam breaks basically, enters embodiment 41 described MSTLFLO cats head with 2 liters/minute flow velocity continuously.Air sprays from the bottom of tower and enters, and flow velocity is 2SCFM.Tower moves more than 30 minutes continuously.The rate of recovery average out to 81.5% of carotenoid in the foam.Embodiment 45

In the test similar to embodiment 41, salt solution enters in the MSTLFLO tower with 3.25 liters/minute flow velocity.Tower moved more than 30 minutes, the rate of recovery average out to 86.3% of carotenoid in the foam.Embodiment 46

In the test similar to embodiment 45, salt solution enters in the MSTLFLO tower with 1.14 liters/minute flow velocity.Tower moved more than 30 minutes, the rate of recovery average out to 84.9% of carotenoid in the foam.Embodiment 47

In the test similar to embodiment 41, salt solution enters in the MSTLFLO tower with 0.69 liter/minute flow velocity.Tower moved more than 45 minutes, the rate of recovery average out to 81.1% of carotenoid in the foam.The c.Canadian tower

Above-mentioned MSTLFLO tower moves unloading except behind all drainage tubes.Do not add pore forming material.Brinish pH value is 6-7.Use identical atomizer.Feed distributor is installed in 36 inches places, foam overflow weir below.Embodiment 48

Bubble column is filled the salt solution that contains carotenoid.Air velocity and raw material flow rate are respectively 5SCFH and 5.8 liters/minute, make that the ratio of air and raw material is 0.41.Tower moves in a continuous manner, and raw material, foam and bottoms stream sample are gathered when 5 minutes gaps.J _gValue is 0.49 cel.The liquid hold-up time is 3.1 minutes.The solid percentage is about 0.7% (not calculating gas) in the foam.The rate of recovery of carotenoid is 65%.Embodiment 49

The salt solution that contains Dunaliella salina suspension is handled with froth flotation equipment.After foam breaks basically, join diameter and be in 4 inches the bubble column.Air enters in the tower by the flow velocity of atomizer with 20 SCFM from the bottom of tower.After the flotation 12 minutes, the rate of recovery 90% of carotenoid in the foam.D. gas-sparged hydrocyclone (ASH) embodiment 50

Before feedstream began with set-point to add, gas began to flow into gas-sparged hydrocyclone with required flow velocity.20 microns of the aperture average out to of polyethylene film are formed by plastic casing and 2 inches diameter, the polyethylene film that is about 18 inches in the ASH unit.The gaseous tension that film is executed pressure side maintains 15-10 pound/square inch.Do not add surfactant and promote flotation.Gather raw material, foam and bottoms stream sample assessment ASH performance.J _gValue is 5.9 cels.Gas and material rate are 5.8.The liquid hold-up time is 1.3 seconds.The solid percentage is about 0.09% (not calculating gas) in the foam.The rate of recovery of carotenoid is 68%.Embodiment 51 to 54

Arrangement embodiment 50LASH unitary data are to determine to extract the rate of recovery and the concentration of carotenoid from disruptive algae.The results are summarized in table 10.Pressurized air is by the hole wall of movable flow device.Pack into the top of movable flow device of raw material.The foam overflow of enrichment carotenoid is flowed out, and the salt solution that does not contain algae flows out as substrate.

The rate of recovery of carotenoid and concentration among table 10 ASH

Embodiment number	Feed pressure (pound/square inch)	Raw material flow rate (gallon per minute)	Gas/raw material capacity ratio, Q*	The carotenoid rate of recovery (%)
Embodiment number	Feed pressure (pound/square inch)	Raw material flow rate (gallon per minute)	Gas/raw material capacity ratio, Q*	The carotenoid rate of recovery (%)	????51	????7	????11.8	????5.7	????40
????52	????6	????11.8	????2.9	????52	????51	????7	????11.8	????5.7	????40
????52	????6	????11.8	????2.9	????52	????53	????7	????11.8	????5.7	????49
????54	????7	????11.8	????5.8	????68	????53	????7	????11.8	????5.7	????49

E. the extraction 1. solvent distribution coefficients of valuable components

For for the carotenoid that extracts the Dunaliella salina, measure its distribution coefficient between salt solution and all kinds of SOLVENTS down at 25 ℃, be used for extraction step to select suitable solvent.3 milliliters of solvents and 12 milliliters of algae concentrated solutions add in 25 milliliters the test tube.Before decant and sampling, fully shake and mix test tube to finish the transfer of material.The results are summarized in table 11.Distribution coefficient is defined as carotenoid concentration in the organic phase/aqueous phase carotenoid concentration.

Under 25 ℃ in the table 11, the distribution coefficient of carotenoid between salt solution and several organic solvent

Embodiment number	Solvent	The rate of recovery (%) of carotenoid in solvent	Distribution coefficient (organic phase/water)
Embodiment number	Solvent	The rate of recovery (%) of carotenoid in solvent	Distribution coefficient (organic phase/water)	????55	Phenyl aldehyde	????99.4	????159
????56	Decyl alcohol	????98.6	????73	????55	Phenyl aldehyde	????99.4	????159
????56	Decyl alcohol	????98.6	????73	????57	Ethyl acetate	????100	????＞1000
????58	Ethyl butyrate	????98.7	????79	????57	Ethyl acetate	????100	????＞1000
????58	Ethyl butyrate	????98.7	????79	????59	2-heptanone	????99.7	????31
????60	Suitable-blatter alcohol	????99.7	????31	????59	2-heptanone	????99.7	????31
????60	Suitable-blatter alcohol	????99.7	????31	????61	Isoamyl Acetate FCC	????99.9	????958
????62	Isobutyl acetate	????100	????＞1000	????61	Isoamyl Acetate FCC	????99.9	????958
????62	Isobutyl acetate	????100	????＞1000	????63	Octanal	????93.2	????14

2. liquid extraction

The salt solution that the contains Dunaliella salina suspension flotation cell of packing into mixed 10 minutes.Collect spissated foam, in flotation cell with air mixed 10 minutes.2000 milliliters through twice spissated foam that contains carotenoid packed 3 liters mixing tank into 400 milliliters of solvents in, the geometrical dimension such as the table 12 of mixing tank are listed.

Table 12 is used for the specification of the mixing vessel and the impeller of substance transfer kinetic test

Project	Specification
Project	Specification	Impeller	6 flat blade Rushton turbines
Diameter	2.5 inch	Impeller	6 flat blade Rushton turbines
Diameter	2.5 inch	The dish diameter	2.0 inch
Width of blade	0.5 inch	The dish diameter	2.0 inch
Width of blade	0.5 inch	Depth of blade	9/16 inch
Container	Cylindrical, have 4 equally spaced inducers	Depth of blade	9/16 inch
Container	Cylindrical, have 4 equally spaced inducers	Diameter	5.75 inch
Liquid height	7.75 inch	Diameter	5.75 inch

Mixture stirred 20 minutes under the 600rpm rotating speed.Timing acquiring brine sample measurement of species transfering dynamics.After 20 minutes, stop the mixing tank record and be separated the time.The phase of deoiling of inclining, the salt water returns mixing tank.400 milliliters of fresh solvents add in the extractor, and multiphase mixture stirred 20 minutes under the 600rpm rotating speed.Be separated once more 20 minutes.The solvent phase in extracted twice stage all left standstill 4 hours again, to reduce gluey algae residue volume.Centrifugal solids is to separate solvent and salt water from the algae residue.Evaporative removal solvent from the carotenoid extract adds sweet oil, forms carotenoid sweet oil suspension.The extraction and the data that are separated provide in the following embodiments.Embodiment 65 utilizes heptane to extract carotenoid from spissated foam.

Total extraction step as mentioned above.2530 spissated foams of gram and 280 gram heptane add in the mixing tank.Rate of recovery data are summarized in table 13.Table 13 utilizes heptane to extract the mixing tank/settling vessel kinetics of carotenoid from Dunaliella salina

Stage #	Mixing time (minute)	The carotenoid rate of recovery (%)
Stage #	Mixing time (minute)	The carotenoid rate of recovery (%)	????1	????20	????97.7％
????2	????20	????71.7％	????1	????20	????97.7％

Embodiment 66 utilizes Limonene to extract carotenoid from spissated foam.

Total extraction step as mentioned above.2516 spissated foams of gram and 343 gram Limonenes add in the mixing tank.Rate of recovery data are summarized in table 14.Table 14 utilizes Limonene to extract the mixing tank/settling vessel kinetics of carotenoid from Dunaliella salina

Stage #	Mixing time (minute)	The carotenoid rate of recovery (%)
Stage #	Mixing time (minute)	The carotenoid rate of recovery (%)	????1	????20	????95.0％
????2	????20	????84.7％	????1	????20	????95.0％

Embodiment 67 utilizes ethyl butyrate to extract carotenoid from spissated foam.

Total extraction step as mentioned above.2499 spissated foams of gram and 353 gram butylacetates add in the mixing tank.Rate of recovery data are summarized in table 15.Wheel speed is 800rpm.Table 15 utilizes ethyl butyrate to extract the mixing tank/settling vessel kinetics of carotenoid from Dunaliella salina

Stage #	Mixing time (minute)	The carotenoid rate of recovery (%)
Stage #	Mixing time (minute)	The carotenoid rate of recovery (%)	????1	????10	????95.4％

Embodiment 68 utilizes sweet oil to extract carotenoid from spissated foam.

Total extraction step as mentioned above.1845 spissated foams of gram and 280 gram sweet oil add in the mixing tank.After 10 minutes, the rate of recovery of carotenoid is 77% in the foam.Embodiment 69 residual solution purify.

To add in the flotation cell from second 2000 milliliters of residual solution extracting the stage, under the 2000rpm rotating speed, mix 20 minutes.After 16 minutes, the rate of recovery of carotenoid is 82% in the foam.Embodiment 70 residual solution purify.

Saturated NaCl salt solution contacts with solvent, reaches balance at 25 ℃.Measure the concentration of solvent in the saturated brine.Gac is added in the solution, and mixed serum is until balance.Carbon is sedimentation from slurries, gathers brine sample, measures solvent strength.The results are shown in table 16.The concentration of solvent (ultimate value that solvent strength is measured in the salt solution is 5ppb) in the saturated NaCl salt solution before and after the absorption of table 16 carbon-coating

Solvent	The concentration of solvent in the saturated NaCl salt solution before the carbon-coating absorption	The concentration of solvent in the saturated NaCl salt solution in carbon-coating absorption back
Solvent			Heptane	????875ppb	????＜5ppb
Limonene	????125ppb	????＜5ppb	Heptane	????875ppb	????＜5ppb

3. liquid extraction mass transfer kinetics

Mass transfer kinetics is mainly measured in 3 liters cylindrical vessel, and the geometrical shape of container has been summarized in table 12.Impeller is installed in container central authorities.According to asynchronism(-nization), collect the sample of liquid/liquid dispersion system, measure the concentration of aqueous phase carotenoid.This research the results are summarized in table 17.Table 17 wheel speed and solvent and material rate extract the influence of the carotenoid rate of recovery in the body to liquid

Embodiment number	Solvent	Wheel speed (rpm)	Solvent/material rate (v/v)	The rate of recovery of carotenoid (%) after 10 minutes
Embodiment number	Solvent	Wheel speed (rpm)	Solvent/material rate (v/v)	The rate of recovery of carotenoid (%) after 10 minutes	????71	Limonene	????600	????0.21	????92.1
????72	Limonene	????600	????0.15	????91.6	????71	Limonene	????600	????0.21	????92.1
????72	Limonene	????600	????0.15	????91.6	????73	Limonene	????600	????0.10	????87.8
????74	Limonene	????600	????0.05	????82.3	????73	Limonene	????600	????0.10	????87.8
????74	Limonene	????600	????0.05	????82.3	????75	Ethyl butyrate	????600	????0.20	????99.1
????76	Ethyl butyrate	????600	????0.15	????97.8	????75	Ethyl butyrate	????600	????0.20	????99.1
????76	Ethyl butyrate	????600	????0.15	????97.8	????77	Ethyl butyrate	????600	????0.10	????97.8
????78	Ethyl butyrate	????600	????0.05	????97.1	????77	Ethyl butyrate	????600	????0.10	????97.8
????78	Ethyl butyrate	????600	????0.05	????97.1	????79	Ethyl butyrate	????500	????0.10	????96.9
????80	Ethyl butyrate	????700	????0.10	????98.5	????79	Ethyl butyrate	????500	????0.10	????96.9

4. extract carotenoid embodiment 81 continuously with Limonene

Contain in the flow velocity adding Denver#5 water treatment flotation cell of salt solution with 10 gallon per minute of Dunaliella salina suspension, its volume is about 100 gallons.From flotation cell, reclaim spissated foam, together join in 3 liters the mixing tank with Limonene.The geometrical property of mixing tank and impeller is identical with table 12 column data, and wheel speed is 600rpm.The effluent of mixing tank is pumped to decanting vessel by a line strainer of breaking gelationus algae residue.Decanting vessel is equipped with the distiller pad of 4 inches of diameters, 12 inches of length, derives from Parasippany, the Otto York of New York.Solvent phase overflows decanting vessel, enters medial launder, pumps into the flash vaporization jar again.Before this unit operation, in the flash vaporization jar, add sweet oil.Evaporative removal solvent in the flash vaporization jar, carotenoid reclaims with its form of suspension in sweet oil.The solvent of evaporation is condensed, and returns mixing tank.The rate of recovery of extracting is listed in table 18.Rate of recovery average out to 60% in this process bubble cell.

Table 18 extracts the effect of carotenoid continuously from salt solution with Limonene

Volume ratio in the disperse phase (Limonene)	The carotenoid rate of recovery (%)
Volume ratio in the disperse phase (Limonene)	The carotenoid rate of recovery (%)	????0.2	????83.2
????0.15	????81.2	????0.2	????83.2

Foregoing invention has been described particularly preferred embodiment.But the description of front will not limit the invention to specific embodiment, and one skilled in the art would recognize that the description according to the front, can carry out various variations in aim of the present invention and scope.In the scope of the invention of claims definition, the present invention includes all replacements, modification and equivalent.

Claims

1. little algae aqeous suspension dehydration method comprises following steps:

(a) obtain the algae aqeous suspension from the algae source;

(b) the algae cell that breaks;

(c) aqeous suspension is fed foam flotation tower, in tower, flow downward by action of gravity;

(d) produce thin bubble, form clean adverse current with aqeous suspension, closely to contact with aqeous suspension;

(e) bubble absorption algae cell forms bubble algae aggregation; With

(f) foam of formation bubble algae aggregation.

2. the described method of claim 1, the step (d) that wherein produces thin bubble comprises jet flow stream and enters in the tower.

3. the described method of claim 1, the step (d) that wherein produces thin bubble is finished in the tower outside, and bubble is imported in the tower.

4. the described method of claim 1 also is included in the step of recirculated water suspension in the tower internal recycle loop, promotes that rill contacts with the tight of algae cell.

5. the described method of claim 1, wherein tower comprises the cycling stream zone that at least one is limited by vertical inducer, and inducer is divided into upper reaches pipe and downspout conductor with tower, and wherein gas and liquid make progress in the pipe of upper reaches and stream, in downspout conductor, also flow downwards, to promote tight contact.

6. the described method of claim 5, wherein tower comprises the multi-stage circulating-flow zone, separates by inducer between the zone.

7. the described method of claim 6, also comprise following steps in the inducer zone above the cycling stream zone: 1) change air flow direction it is upwards flowed, therefore, make by the gas in dirty area under control minimum, with 2) change liquid stream and flow to and it is flowed downward enter dirty area under control, the liquid in wherein adjacent two cycling stream zones exchanges and can avoid substantially.

8. the described method of claim 5, wherein vertical inducer is made up of the drainage tube that is installed in tower central authorities.

9. the described method of claim 1, wherein tower comprises at least one cycling stream zone, it defines a radially inner zone and radially outer annular region, this method also comprises promotion radially to the inner compartment step higher than the gas hold up of annular region, what algae suspended circulates in cycling stream, upwards by radially inner zone, downwards by annular region, to promote tight contact.

10. the described method of claim 9, wherein tower comprises the multi-stage circulating-flow zone, separates by inducer between the zone.

11. the described method of claim 10, also comprise following steps in the inducer zone above the cycling stream zone: 1) change air flow direction, it is upwards flowed, thereby make by the gas in dirty area under control minimum, with 2) the change liquid stream flow direction, it is flowed downward, make it enter dirty area under control, the liquid in wherein adjacent two cycling stream zones exchanges and can avoid substantially.

12. the described method of claim 9, wherein vertical inducer is made up of the drainage tube that is installed in tower central authorities.

13. the described method of claim 1, wherein tower comprises at least one cycling stream zone, define a basic inside zone and outside substantially annular region, it is basic to the high step of the gas hold up of inner compartment that this method also comprises the basic outwards annular region of promotion ratio, by the circulation downwards in cycling stream of basic outwards annular region algae suspension, by substantially to inner compartment in cycling stream to cocycle, to promote tight contact.

14. the described method of claim 13, wherein tower comprises the multi-stage circulating-flow zone, separates by inducer between the zone.

15. the described method of claim 14, inducer zone above the cycling stream zone also comprises following steps: 1) change air flow direction it is upwards flowed, therefore, make by the gas in dirty area under control minimum, with 2) change liquid stream and flow to and it is flowed downward enter dirty area under control, the liquid in wherein adjacent two cycling stream zones exchanges and can avoid substantially.

16. the described method of claim 13, wherein vertical inducer is made up of the drainage tube that is installed in tower central authorities.

17. the described method of claim 1 also comprises the step of breaking foam, and the further condensed water suspension of repeating step (c) to (f) here.

18. the described method of claim 1, wherein aqeous suspension is the suspension of Dunaliella salina in salt solution.

19. the dehydration method of a Dunaliella salina salt aqeous suspension comprises following steps:

(a) obtain algae suspension from the algae source;

(b) the algae cell that breaks;

(c) suspension is fed foam flotation tower, in tower, flow downward by action of gravity;

(d) produce thin bubble, form clean adverse current with suspension, closely to contact with suspension;

(e) loop suspension in tower internal recycle loop promotes that rill contacts with the tight of algae cell;

(f) bubble absorption algae cell forms bubble algae aggregation; With

(g) foam of formation bubble algae aggregation.

20. the described method of claim 19, wherein tower comprises the cycling stream zone that at least one is limited by vertical inducer, and inducer is divided into upper reaches pipe and downspout conductor with tower, and wherein gas and liquid make progress in the pipe of upper reaches and stream, in downspout conductor, also flow downwards, to promote tight contact.

21. the described method of claim 20, wherein tower comprises the multi-stage circulating-flow zone, separates by inducer between the zone.

22. the described method of claim 21, inducer zone above the cycling stream zone also comprises following steps: 1) change air flow direction it is upwards flowed, therefore, make by the gas in dirty area under control minimum, with 2) change liquid stream and flow to and it is flowed downward enter dirty area under control, the liquid in wherein adjacent two cycling stream zones exchanges and can avoid substantially.

23. the described method of claim 20, wherein vertical inducer is made up of the drainage tube that is installed in tower central authorities.

Mix carotenoid 24. a method of separating Dunaliella salina from salt solution, isolating algae are used for reclaiming, the method includes the steps of:

(a) obtain the suspension of Dunaliella salina salt solution from its source;

(b) the algae cell that breaks;

(c) salt solution is fed the multi-stage circulating-flow flotation tower, substantially flow downward in tower by action of gravity, this tower comprises at least two cycling stream zones that limited by vertical inducer, inducer is divided into upper reaches pipe and downspout conductor with tower, wherein gas and liquid make progress in the pipe of upper reaches and stream, also flow downwards in downspout conductor;

(d) enter in the upper reaches pipe of minimum race way by jet flow stream, gas is dispersed into rill, and adverse current is passed through salt solution;

(e) make pipe interior gas hold up in upper reaches than gas hold up height in the downspout conductor, salt solution to cocycle, upwards by the upper reaches pipe, passes through downspout conductor downwards in cycling stream;

(f) air-flow in the pipe of upper reaches is upwards flowed, make the gas fractional flow that enters downspout conductor minimum;

(g) make the liquid in the pipe of upper reaches flow to current downflow, make it enter dirty area under control, the liquid in wherein adjacent two cycling stream zones exchanges and can avoid substantially, and rill closely contacts the surface that algae is adsorbed in bubble with the algae cell; With

(h) foam of formation enrichment algae, algae has realized separating with salt solution.

25. the described method of claim 24 also comprises the step that breaking foam obtains the algae enriched material, wherein repeating step (c) to (i) is to obtain to mix the concentration extracted of carotenoid.

26. the described method of claim 24 also comprises the step that breaking foam obtains the algae enriched material, wherein repeating step (c) to (i) is to obtain the required mixing carotenoid concentration of cross-flow microfiltration.

27. the described method of claim 24 also comprises following steps: a) cross-flow microfiltration algae enriched material makes the mixing carotenoid concentration in the stagnant liquid can carry out the high density gas extraction; B) from stagnant liquid, extract mixing carotenoid with the high density gas extraction method, obtain exsiccant mixing carotenoid extract.

28. the described method of claim 27 also comprises the step by chromatography purification mixing carotenoid.

29. the described method of claim 24, wherein superficial gas velocity J _gBe about 0.1 to 1.0 cel.

30. the described method of claim 24, wherein the ratio of gas and raw material is about 0.1 to 1.5.

31. the described method of claim 24, wherein the liquid hold-up time is about 2 to 20 minutes.

32. the described method of claim 24, wherein solid accounts for the percentage of foam wt in the foam, does not calculate gas weight, is about 60ppm to 17%.

33. the described method of claim 24, wherein said gas does not contain oxygen.

34. a method of extracting blended carotenoid from Dunaliella salina, the method includes the steps of:

(a) obtain the suspension of Dunaliella salina salt solution from its source;

(b) the algae cell that breaks;

(c) algae suspension is fed the multi-stage circulating-flow flotation tower, flow downward only in tower by action of gravity, this tower comprises at least two cycling stream zones, and each zone all defines a radially inner zone and a radially outer annular region;

(d) by the gas that sprays oxygen-free gas enter minimum race way radially in inner compartment, form clean adverse current, its superficial gas velocity J by suspension _gBe about 0.1 to 1.0 cel, the ratio of gas and raw material is about 0.1 to 1.5;

(e) impel substantially gas hold up to inner compartment than annular region height, algae suspension circulates in cycling stream, upwards by radially to inner compartment, passes through annular region downwards;

(f) radially to the air-flow of inner compartment upwards and radial inward flow moving, make by the gas of annular region minimum;

(g) liquid is flowed to down and flow radially outward, make it enter annular region, do not carry out backmixing substantially, and rill closely contacts with algae suspension, algae is adsorbed in bubble surface;

(h) foam of formation enrichment algae, algae has realized separating with salt solution;

(i) breaking foam obtains the algae enriched material; With

(j) repeating step (c) to (i) to be to obtain spissated mixing carotenoid, and promptly solid accounts for the percentage of foam wt in the foam, does not calculate gas weight, is about 1 to 17%.