EP2988759A1 - Method for extracting organic solids and oil from marine organisms enriched with astaxanthin - Google Patents

Abstract

The present invention relates to a method for extracting shrimp oil. Particularly, shrimp processing water (EPC) is recovered and subjected to a dissolved air flotation (DAF) system after adding a flocculating agent. The suspended and dissolved solids form aggregates that are recovered from the surface by means of a procedure referred to as "skimming". The skimming product is then directed into a horizontal centrifuge (settling tank) in order to separate the solid phase (SOC) and the liquid phase consisting of water and shrimp oil. The liquid phase is pumped into the 3-phase vertical centrifuge in order to separate the shrimp oil, the water, and the solids. The solids recovered after using the separator can then be added to the solid phase obtained after settling. The resulting shrimp oil is very rich in astaxanthin, and the resulting water contains very little organic material and can be returned to the general processing plant effluent.

Description

 PROCESS FOR EXTRACTING ORGANIC SOLIDS AND OIL

 MARINE ORGANISMS ENRICHED WITH ASTAXANTHINE

References to previous requests

[0000] This application claims priority of the US provisional application

61 / 782,013 filed March 14, 2013, the contents of which are fully incorporated by reference.

Field of the invention

The present invention relates to a method for extracting organic solids and oil of marine organisms, particularly crustaceans, rich in astaxanthin, and astaxanthin enriched compositions resulting therefrom.

Prior art

[0002] Fishermen's cooperatives and other fish processing companies process millions of pounds of shrimp a year. The main finished product, cooked and frozen shrimp, is then distributed on national and international markets. The shrimp processing process includes several stages (cooking, cooling, dehulling, inspection, brining, dripping, freezing, etc.) and requires a very large quantity of drinking water (about 2000 L / min). Transformation of the shrimp generates an effluent that contains approximately 18,000 mg / L total solids (ST), consisting of approximately 2,000 mg / L total suspended solids (SST) and approximately 16,000 mg / L solids. total dissolved solids (SDT). These raw material particles contain on average 3000 mg / L of crude protein and about 800 mg / L of fat (oil).

Until recently, these effluents, considered to be readily biodegradable, were discharged into the environment without any treatment contributing to a considerable loss of raw material and pollution of the surrounding coastal waters. In order to remedy this problem, a process and an effluent treatment unit have been put in place, including a dissolved air flotation system (DAF). DAF treatment recovered above 80% of the suspended solids contained in the shrimp effluents in the form of organic sludge. These contain at most 8% solids and 92% water. This sludge was then partially dewatered using a horizontal two-phase centrifuge called "decanter". The sludge recovered after the decanter contains approximately 18% total solids which consist of less than 2% fat and 11% crude protein. It is therefore possible to use them as ingredients for animal feed. Due to the fact that this is the last stage of shrimp effluent treatment, the effluent obtained after the decanter stage can now be discharged into the environment.

A sample taken from this decanter effluent for analysis has particularly attracted our attention by its dazzling orange-pink coloring. Thanks to our expertise in the field of physicochemical characterization of marine and derived products, we understood that this color was due to astaxanthin, a carotenoid pigment that is responsible for the orange-pink coloring of the flesh of salmonids and fish. crustaceans (crab, shrimp, lobster). Surprisingly, we realized that our process also allowed to concentrate the pigments

carotenoids that were solubilized in the water used during the shrimp processing process. Knowing that astaxanthin is of great economic interest, the effluent obtained after the decanter stage has become an object of detailed study on our part. The physicochemical analyzes of the decanter effluent showed that it contained a significant amount of shrimp oil and crude protein. Since astaxanthin is a very oil-soluble pigment, we aimed to extract the oil from its aqueous medium to obtain a high-added product, rich in astaxanthin. Generally, this pigment can be extracted from crustacean shells by various techniques (e.g., enzymatic digestion) during the production of chitin / chitosan but the industrial processes used for this operation are usually slow and expensive.

[0006] As a result, the effluent resulting from the processing of the shrimp represents an alternative and very advantageous source for obtaining concentrated astaxanthin in the form of shrimp oil. We have therefore developed a process for extracting astaxanthin-rich shrimp oil from shrimp processing effluent, which was once released into the environment. Summary of the invention

According to a first aspect, the invention relates to a process for extracting oil and organic solids from marine organisms, particularly an oil and an organic solid enriched in active ingredient, among others astaxanthin. In accordance with one particular aspect, the invention relates to a method for extracting oil of marine origin, comprising:

 (a) obtaining a treatment effluent from a marine organism;

 b) adding a flocculant to the treatment liquid of a) and separating an aqueous phase from the flocculated solids at the surface to recover the solids;

 c) separating the solids recovered in b) into a solid phase and a liquid phase and recovering the solid phase and / or the aqueous phase;

 d) subjecting the liquid phase obtained in c) to vertical centrifugation to obtain an aqueous phase and an oil; and

 e) recover the oil thus separated. In particular, in step b) the separation of the aqueous phase of the flocculated solids at the surface is carried out with a dissolved air flotation system (DAF); in step c) the separation of said flocculated solids in b) into a solid phase and a liquid phase is carried out with a horizontal 2-phase centrifuge (decanter); and in step d) obtaining the aqueous phase and the oil is carried out by subjecting the liquid phase obtained in c) to vertical centrifugation (separator).

In accordance with another aspect, the method also comprises the following step: f) the solid phase recovered in step c) is then dried to form an organic solid enriched in proteins.

In accordance with a particular aspect, the invention relates to the oil as obtained by the process defined herein. In particular, shrimp oil comprises more than 800 μg / g (ppm) of astaxanthin, more than 500 μg / g of vitamin E; more than 2000 IU / 100g of vitamin A; and more than 13g / 100g des-3 fatty acids. In accordance with a particular aspect, the invention also relates to a solid residue as obtained by the process defined herein. In particular, the solid residue comprises more than 60% proteins; more than 400 pg / g of vitamin E; more than 4000 IU / 100g of vitamin A; and more 350 μg / g astaxanthin. Alternatively, the invention relates to a composition comprising an oil and / or an organic solid as defined herein, mixed with an excipient. In particular, the excipient is a flour, particularly a flour enriched with marine proteins. In accordance with a particular aspect, the invention also relates to the use of an oil or solid residue as defined herein as a food additive in an aquaculture feed.

[0013] Also, the invention relates to the use of an oil or organic solids as defined herein for the production of a food or a food supplement. In particular, the food or dietary supplement is intended for human, animal (such as farm animals, domestic animals) or aquaculture. More particularly, the food additive is used in an aquaculture feed.

Still, in accordance with a particular aspect, the invention also relates to the use of an oil or the solid product as defined herein as a food additive in feeds for birds such as laying hens and other poultry .

Detailed Description of the Invention Description of the Figures

Figure 1. Schematic of the extraction process of the shrimp oil. Figure 2. Variation of the crude protein concentration in the mud recovered from the settler as a function of the increase in the speed of rotation of the decanter bowl during experiments A, B and C.

Figure 3. Variation of the concentration of fat in the sludge recovered from the settler as a function of the increase in the speed of rotation of the decanter bowl during the experiments A, B and C.

Figure 4. Variation of the concentration of total solids in the decanter effluent as a function of the increase in the speed of rotation of the decanter bowl during experiments A, B and C. Figure 5. Variation of the concentration of total suspended solids in the decanter effluent as a function of the increase in the speed of rotation of the decanter bowl during experiments A, B and C.

Figure 6. Variation in the concentration of crude protein in the decanter effluent as a function of the increase in the speed of rotation of the decanter bowl during the experiments of A, B and C.

Figure 7. Variation of the concentration of fat in the decanter effluent as a function of the increase in the speed of rotation of the decanter bowl during experiments A, B and C. Figure 8: Effect of the temperature and speed of the settler on the

fat concentration (MG) in the decanter effluent.

[0023] Figure 9: Effect of the temperature and the speed of the settler on the

total solids (ST) concentration in the decanter effluent.

[0024] FIG. 10: Effect of the temperature and the speed of the decanter on the

percentage of total solids (ST) and fat (MG) in organic shrimp solids (SOC).

Figure 11: Effect of the SKIM temperature on the concentration of total solids and fat effluent decanter when the decanter rotates at 2700 rpm.

Figure 12: Effect of temperature on the percentage of total solids and fat in the SOCs.

Abbreviations and definitions

Abbreviations

DAF: dissolved air flotation; DEC: decanter or horizontal centrifuge with 2 phases; EC: heat exchanger; EPC: shrimp process water: cooking water, rinsing water, etc .; PL-E: liquid phase; PS-RC: solid phase; HC: shrimp oil; MO: organic matter; SEP: vertical separator or centrifuge; R1: receptacle 1; R2: receptacle 2; SDT: total dissolved solids; SKIM: layer flocculated solids on the surface of the liquid phase; SOC: organic shrimp solids; SST: total suspended solids; and ST: total solids.

Definitions

 The use of the term "about" as used herein refers to a margin of error of + or - 5% of the indicated number. For the sake of precision, the term "about" when used, for example with the term 90%, means 90% +/- 4.5% i.e. from 86.5% to 94.5%.

The term "solid residue" as used herein refers to a shrimp "protein concentrate" or other marine organism resulting from the present process, and these two terms may be used interchangeably.

Detailed description of particular achievements

The present invention relates to the recovery of wastewater effluents from the processing and production of marine organisms such as fish (including fatty fish) and crustaceans (including herring, sardines, among others). mackerel, salmon, trout, shrimp, crab, lobster and krill). The food processing of these organisms is causing unsuspected coastal zone pollution and the plaintiff has found, quite fortuitously, that a method to reduce the organic load of the plant effluents made it possible to isolate an oil. and a flour of these marine organisms, greatly enriched in active principles and thus having a high added value.

Shrimp processing

The prawn processing method comprises several steps (cooking, cooling, dehulling, inspection, brining, dripping, freezing, etc.) and requires a very large amount of drinking water (about 2000 L / min). Transformation of the shrimp generates an effluent that contains approximately 18,000 mg / L total solids (ST), consisting of approximately 2,000 mg / L total suspended solids (SST) and approximately 16,000 mg / L solids. total dissolved solids (SDT). These raw material particles contain on average 3000 mg / L of crude protein and about 800 mg / L of fat (oil). Until recently, these effluents, considered to be readily biodegradable, were discharged into the environment without any treatment contributing to a considerable loss of raw material and pollution of the surrounding coastal waters. In order to remedy this problem, the Applicant has implemented a process and an effluent treatment unit, including among others a dissolved air flotation system (DAF). DAF treatment recovered above 80% of the suspended solids contained in the shrimp effluents in the form of organic sludge. These contain at most 8% solids and 92% water. This sludge was then partially dewatered using a horizontal two-phase centrifuge called "decanter". The sludge recovered after the decanter contains about 18% total solids which consist of less than 2% fat and 1 1% crude protein. It is therefore possible to use them as ingredients for animal feed. Due to the fact that this is the last stage of shrimp effluent treatment, the effluent obtained after the decanter stage can now be discharged into the environment.

In an unforeseen event (breakage), a sample taken from this decanter effluent for analysis has particularly caught our attention with its dazzling orange-pink coloring. Following a physicochemical characterization of marine and derived products, we have established that this color was due to astaxanthin, a carotenoid pigment that is responsible for the orange-pink coloring of the flesh of salmonids and crustaceans (crab, shrimp, lobster). Surprisingly, we realized that our process also allowed us to concentrate the carotenoid pigments that were solubilized in the water used during the process of shrimp processing. Knowing that astaxanthin is of great economic interest, the effluent obtained after the decanter stage has become an object of detailed study on our part.

The physico-chemical analyzes of the decanter effluent showed that it contained a significant amount of shrimp oil and crude protein.

Knowing that astaxanthin is a very oil-soluble pigment, we aimed to extract the oil from its aqueous medium to obtain a high-added product, rich in astaxanthin. Generally, this pigment can be extracted from crustacean shells during the production of chitin / chitosan by enzymatic digestion, but this industrial process is very slow and expensive. The process

 In accordance with a particular aspect, the invention relates to a crustacean oil extraction process, comprising:

 (a) obtaining a treatment effluent from a marine organism;

 b) adding a flocculant to the treatment liquid of a) and separating an aqueous phase from the flocculated solids at the surface to recover the solids;

 c) separating said recovered solids in b) into a solid phase and a liquid phase and recovering the solid phase and / or the aqueous phase;

 d) subjecting the liquid phase obtained in c) to vertical centrifugation to obtain an aqueous phase and an oil; and

 e) recover the oil thus separated.

Particularly, in step b) the separation of the aqueous phase flocculated solids surface is performed with a dissolved air flotation system (DAF); in step c) the separation of said flocculated solids in b) into a solid phase and a liquid phase is carried out with the aid of a horizontal centrifuge with 2 phases called decanter (DEC); and in step d) obtaining the aqueous phase and the oil is carried out by subjecting the liquid phase obtained in c) to a vertical centrifugation called separator (SEP).

flocculant

Flocculation is a process of agglomeration of solid particles (fat and crude protein) around the flocculant having an opposite charge. The products used are preferably identified as safe (Generally Recognized as Safe, GRAS). According to a particular embodiment, the flocculant added to the shrimp processing liquid is chosen from: natural or synthetic polymers, whether they are cationic (positively charged) or anionic (negatively charged).

The recovery of the organic matter (protein and oil) from the effluent of the transformation of marine organisms with anionic flocculant comprises three stages: acidification (addition of a sulfuric acid), coagulation (addition of a coagulant, FeCl ₃ or AICI ₃ ) and flocculation (addition of anionic flocculant such as polyacrylamide or alginate). While cationic flocculants do not require any pretreatment of the effluent. Especially, the anionic flocculant and is selected from: Polyfloc AP1 1 10 (from Ge Water Technologies). More particularly, the chosen flocculant is a cationic flocculant such as polyacrylamide or chitosan. Even more particularly, the cationic flocculant is chosen from: Polyfloc CP1 158 (from Ge Water Technologies); and GR-505 (from NALCO).

DAF

According to a particular embodiment of the invention, the separation of the flocculated solids from the solvent in step b) is carried out by means of a dissolved air flotation system (DAF). According to this embodiment, the dissolved air attaches to the flocculated solids ("flocs") and brings them to the surface where they float and are then recovered by a procedure called "skimming" in which the upper layer of aggregates (flocculated solids) on the surface.

The treatment liquid is usually at room temperature or at about 10 to 18 ° C when it arrives at the dissolved air flotation system.

In particular, the flocculant is added during the transfer of the liquid between the reservoir and the inlet into the DAF system. Decanter (DEC)

 According to a particular embodiment of the invention, the separation of the flocculated solids recovered from step b) into a solid phase and a liquid phase is carried out by means of a horizontal two-phase centrifuge system, commonly known as a "decanter" or DEC. In particular, this decanter has 2 continuous outlets including an output for the solid phase and an output for the liquid phase consisting of water (effluent) and shrimp oil.

According to this embodiment, the liquid phase is recovered following decantation (horizontal centrifugation) with a rotation speed of the bowl between 1800 rpm and 3300 rpm. More particularly, the decanter is operated at a speed between 2000 and 2900 rpm, more particularly between 2500 and 2800 rpm, and even more particularly around 2700 rpm.

Centrifuge (SEP)

According to a particular embodiment of the invention, the separation of the effluent and the oil from the liquid phase obtained at the decanter outlet is achieved by means of a vertical centrifuge (commonly called "separator") where the oil is recovered above the effluent (aqueous phase). In particular, this separator operates continuously and comprises 3 outputs: the top outlet (supernatant); the exit of the center (centrate), and the exit of the bottom (base). Especially, the supernatant contains the oil; the "centrate" consists of water that is almost free of organic matter and can now be discharged into the effluent of the plant without endangering the environment; and the pellet contains a solid phase that can be recovered to enrich a protein meal.

Heat exchangers

 According to a particular embodiment of the invention, each separation step is performed at a previously established temperature in order to optimize the separation of the desired components. Particularly in step a), shrimp is processed at high temperature to cook the shrimp, more particularly, the cooking water is at a temperature of about 100 ° C. The cooking water is then mixed with a large amount of cold water used for cooling and decorticating the shrimp in the receptacle R1 to reach a temperature of about 4 to 25 ° C, more particularly between 8 and 20 ° C, and even more particularly between 10 and 18 ° C when entering the DAF system (step b).

According to a particular embodiment of the invention, this separation step is performed at a previously established temperature in order to optimize the separation of the desired components. In particular, heat exchangers can be installed to control the temperature of the solid and / or liquid phase in order to optimize the separation of the components. More particularly, once stage b) is completed and the solid phase is recovered (skims), it is subjected to a first heat exchanger (EC1) in order to control the temperature before proceeding to the decanter stage. (DEC). More particularly, skim solids are subjected to a heat exchanger in order to raise their temperature to about 20 to 40 ° C, more particularly around 25 to 35 ° C, and even more particularly about 30 ° C. .

Particularly, once step c) completed and the recovered liquid phase (HC + E), it is subjected to a second heat exchanger (EC2) to control the temperature before proceeding to the separator stage (SEP). More particularly, the oil + water mixture is subjected to a second heat exchanger in order to raise their temperature to about 80 to 99 ° C, more particularly around 85 to 98 ° C, and even more particularly about 95 ° C before proceeding to separation in the vertical centrifuge.

Alternatively, if the purpose of the present method is rather to recover the organic material in the solid phase rather than in the liquid phase, once step b) completed and the recovered solid phase (skims), this one is subjected to a first heat exchanger (EC1) in order to increase the temperature before proceeding to the decanter stage (DEC). Thus, more particularly, the skim solids are subjected to a heat exchanger in order to raise the temperature to about 70 to 95 ° C, more particularly around 80 to 90 ° C, and even more particularly about 85 ° C to facilitate the migration of organic matter to the solid phase.

Specific realization of the process

 The shrimp oil extraction process comprises several steps and requires several pieces of equipment. The schematic of a particular embodiment of the prawn oil extraction process is shown in FIG.

The water leaving the shrimp processing process (EPC) is recovered firstly in a tank (R1) (1) for homogenization, and is then pumped at a rate of about 2000 L / min in a dissolved air flotation system (DAF) (2). The EPC temperature is varied from 10 to 18 ° C. A cationic flocculant (or anionic with a) acidification and b) pre-coagulation) is added to the EPC so that suspended and dissolved solids form larger flocs (aggregates). In the DAF system (2) the dissolved air attaches to the flocculated solids and brings them to the surface where they are recovered by a procedure called "skimming". Recovered solids, called skimmings (SKIM), are collected in a second tank (R 2 SKIM) (3). At this stage the SKIMs contain about 6% total solids, oil and 94% water.

The SKIMs are first pumped at 50 L / min in a heat exchanger (EC1)

(4) to raise the temperature to about 30 ° C (80 to 100 ° F), and then to the horizontal centrifuge (DEC) (5). The latter is used to separate the solid phase (organic shrimp solids (PS-RC) (6)) and the liquid phase which is recovered in a third tank (PL-E + HC) (7). This liquid phase (7) is consisting of water and shrimp oil with some traces of crude protein. In order to separate the shrimp oil from the water, the liquid phase is pumped first to a second heat exchanger (EC2) (8) to raise its temperature to about 95 ° C and then to the vertical centrifuge 3 phases (SEP) (9) with 3 continuous outputs. This centrifuge (SEP) separates shrimp oil (phase above), water / effluent (middle phase), and solid residues (phase below). These recovered solids (1 1) are then added to the solid phase (6) obtained after decantation. The shrimp oil obtained (above phase) is recovered in metal drums under nitrogen (HC) (10), and is stored in a cold store at -18 ° C. The water obtained (12) containing very little organic matter (water without MO) is returned to the general effluent of the plant.

Oil / solid obtained and compositions

 Unexpectedly, the implementation of this process produces a very rich oil astaxanthin, containing more than 505 g / g of astaxanthin, particularly more than 510, 525, 550, 580, particularly more than 600 g. / g, more than 700 μg / g, more than 800 μg / g, more than 900 μg / g, or more than 1000 μg / g of astaxanthin. In particular, this oil comes mainly from shrimp.

Also, the present process makes it possible to obtain a solid product comprising more than 60% proteins; more than 12% fat, more than 400 pg / g of vitamin E; more than 4000 IU / 100g of vitamin A; and more than 350 μg / g of astaxanthin. In particular, this residue is called "marine protein concentrate". In particular, this concentrate comes mainly from shrimp. More particularly, this concentrate is dried and optionally milled to make a flour enriched in marine proteins.

According to a particular embodiment, the invention also relates to a composition comprising the oil as defined herein, mixed with an excipient.

 In particular, the excipient may be a solid residue, a concentrate or a flour, more particularly a flour enriched in marine proteins.

According to a particular embodiment, the invention also relates to a feed for feeding at least one farmed fish, said feed comprising an oil or a solid residue as defined herein. According to a particular embodiment, the invention also relates to a dietary supplement comprising an oil or a solid residue as defined herein, one and / or the other being mixed with a physiologically acceptable excipient, particularly in a human. uses

 According to a particular embodiment, the invention also relates to the use of an oil as defined herein as a feed additive in an aquaculture feed (ie for fish raised in fish farming) or poultry, particularly, the use of this oil for the production of a food or a food supplement. In particular, the food or dietary supplement is intended for human, animal, aquaculture or poultry use. Alternatively, the invention relates to the use of a solid product (i.e. residue or concentrate) as defined herein as a food additive in an aquaculture and / or poultry feed.

[0057] In particular, the supplement or food additive is designed to be ingested in liquid or solid form by humans, animals such as farm animals or domestic animals, or by birds or fish.

Methods

 According to a particular embodiment, the invention also relates to a method for feeding a fish raised in fish farming, said method comprising the administration of the feed as defined herein.

[0059] Also, in another particular embodiment, the invention relates to a method for combating radical oxidation in humans, said method

comprising administering an effective dose against oxidation of the dietary supplement as defined herein.

The following examples are for illustrative purposes only, rather than limiting the invention to these particular embodiments. Examples

Example 1

Equipment

 The Dissolved Air Flotation system is a KROFTA brand, model Multifloat, MFV-600 Tandem; the decanter (DEC) is brand SHARPLES, model Super D-CANTER, P3400; and the centrifuge (SEP) is obtained from ALPHA LAVAL model AFPX-409.

Example 2

Determination of the optimal conditions of the decanter operation to extract the maximum amount of oil and the minimum of proteins in the shrimp effluent

The first step of this project aims to find the optimum conditions of the horizontal two-phase centrifuge (decanter) to obtain more oil and less protein in the decanter effluent without affecting the quality recovered organic mud. The speed of rotation of the decanter bowl is a parameter affecting the separation of solids from the liquid. For this, a "gearbox" has been installed on the decanter to control the speed of rotation of the bowl. Three experiments were conducted during three different shrimp processing days to obtain more representative results and to draw reliable conclusions. During the first two experiments (A and B), the efficiency of the decanter operation was evaluated at 7 different decanter bowl rotation speeds, defined in consultation with the ACPI technical team. The third experiment C was performed to confirm the results obtained during the first 2 experiments. The progress of these experiments is described in Table 1.

Table 1. Conduct of the evaluation experiment of the settling tank conditions in experiments A and B.

At each speed, the decanter was operated for half an hour before taking the first sub-samples. Fifteen minutes later, the second sub-samples are taken. Then, after another 15 minutes of operation, the third sub-samples are taken. For each decanter bowl rotation speed, sub-samples were taken from the following locations: 1) influent and DAF effluent (INF DAF, EFF DAF), 2) decanter effluent (EFF Dec ) and 3) the mud of the decanter (Mud Dec). A composite sample was prepared from 3 subsamples of each matrix taken for each decanter rotation rate and physicochemical analyzes were performed.

In order to ensure that the quality of the shrimp effluent and the operating efficiency of the DAF are stable, the DAF influent and effluent composite samples from the three experiments were analyzed and the results of these analyzes are presented in Table 2. Table 2. Results of the evaluation of the physicochemical parameters of the shrimp processing effluent (INF DAF), the DAF effluent (EEF DAF) and the efficiency of the operation of the DAF during the experiments June 9, 19 and 28, 2006.

The results of analyzes of the influent and DAF effluent samples showed that the average total suspended solids (SST) content varied slightly, while that of the total nitrogen (TKN), crude protein (PB) and fat (MG) were similar in all three experiments. The

DAF operation was more effective in experiments B and C, especially with regard to recovery of SSTs (80 and 85% were recovered respectively) and fat (69 and 68% were recovered respectively). The reduction percentages of SST (78 to 85%), TKN (28 to 32%), PB (28 to 32%) and MG (60 to 69%) in the shrimp processing effluent demonstrate that the system DAF works with the same efficiency that was achieved in the previous year after its optimization was finalized. Compound samples of organic sludge recovered from the decanter during the three experiments were analyzed to observe the change in the quality of the organic solids depending on the different speeds (RPM) of the decanter bowl. The results of these analyzes are presented in Table 3.

Table 3. Results of evaluation of the physicochemical parameters of the decanter mud at different rotational speeds of the decanter bowl during the experiments of 9, 19 and 28 June 2006.

The results of the analyzes demonstrated that with the increase in the speed of 0 rotation of the decanter bowl, the percentage of total solids in the sludge was

 increased while that of moisture decreased slightly exp. A, but the contents of these two parameters remained stable in experiments B and C.

[0068] FIG. 2 clearly demonstrates that with the increase in the speed of rotation of the clarifier, there is a slight increase in the crude protein content in the recovered sludge, thus leading to an improvement in the nutritional value of the sludge. . It should be emphasized that it is the proteins that are the main constituent sought if the sludge is used as an additive for the feeding of animals or fish.

The results of the analyzes showed that with the increase in the speed of rotation of the decanter bowl, the percentage of fat (MG) in the mud recovered decreases (Table 3). For example, during the June 9th experiment, the MG content decreased from 3.08% to 1.83% when the decanter bowl rotation speed was increased from 1800 RPM to 3240 RPM. The results of the June 19 analyzes confirmed this trend. Figure 3 clearly shows that during experiments A and B, there is a rapid decrease in MG with the increase in the speed of rotation of the decanter from 1800 to 2700 RPM.

When the speed of rotation of the clarifier exceeds 2700 RPM (75% of the maximum speed), the results obtained are inconclusive. The content of MG continues to decrease for experiment A, whereas for experiment B, an increase in the contents of MG is observed and then a decrease when the rotation speed of the decanter reaches 3240 RPM.

It should be noted that this slight decrease in MG in the mud recovered does not affect its quality because a very high concentration of MG can be harmful during the drying of the sludge. . On the other hand, the MGs that are virtually lost in the mud are found in the effluent of the settler, which increases our chance to cover them in the form of oil using the separator. Thus, the results of the analyzes demonstrated that the rotational speed of the decanter bowl can be changed without significantly affecting the quality of the recovered organic sludge.

In order to more accurately target the optimum speed of the decanter to obtain more oil and less protein in the decanter effluent, the samples composed of the effluent of the decanter of the three experiments A, B and C have have been analyzed. The total solids, total suspended solids, crude protein and fat contents were determined and the results of these analyzes are presented in Table 4.

Table 4. Results of the evaluation of the physicochemical parameters of the samples composed of the decanter effluent at different decanter bowl rotation speeds during the A, B and C experiments.

By examining the results of the analyzes performed on the condenser effluent composite samples, solids (ST and SST), crude protein (PB), and fat (MG) concentrations were found in the water. Effluent increases with increasing speed of rotation of the decanter bowl. The increase in solids (ST and SST), crude protein (PB) and fat in effluent 0 with the increase in the decanter bowl rotation speed results in a decrease in the amount of organic mud recovered without affecting its quality. Figures 4 and 5 confirm this migration of solids in the decanter effluent.

During the tests of experiment A, the concentration of solids (ST and SST) in the effluent increased in a constant and rapid manner with the increase in the speed of rotation of the decanter bowl. The solids concentration reached its maximum (37900 and 49152 mg / L of SST and ST, respectively) at a decanter bowl velocity of 2880 RPM. Subsequently, the levels of SST and ST in the effluent decreased as the speed of the settler bowl was further increased. On the other hand, 0 during experiment B, there was a constant increase in solids (ST and SST) in the effluent with the increase of the speed of rotation of the bowl of the decanter. For example, effluent collected at the highest decant rotation speed of 3240 RPM contained SST and ST levels of 41300 and 55123 mg / L, respectively. It must be emphasized that a high concentration of solids in the effluent can interfere with the proper operation of the separator and prevent extraction of the oil from the aqueous medium in addition to reducing the recovery efficiency of the sludge. Decanter effluent samples taken at bowl rotation speeds greater than 2700 RPM (75% maximum operating speed) are less suitable for optimal oil extraction from decanter effluent because they contain too much solids.

Figure 6 shows that the variation of the crude protein concentration in the decanter effluent as a function of the increase in the speed of rotation of the decanter bowl follows the same trend observed for solids (ST and SST) .

From Figure 6, it is observed that the crude protein content (PB) in the decanter effluent increases with the increase in the speed of rotation of the decanter bowl and this for all tests (A, B and C). It is certain that the migration of the PB in the effluent becomes important when the speed of the bowl of the clarifier reaches 2700 RPM is 75% of the maximum operating speed of the clarifier. Due to the fact that proteins are the main factor that can negatively influence the extraction of shrimp oil from the decanter effluent, it is preferable to work with rotational speeds below 2700 RPM.

The results presented in Table 4 demonstrate that all the samples taken in experiments A, B and C were very high in fat. The lowest MG content was obtained in tests A using a decanter rotation speed of 1800 RPM and amounted to 16030 mg / L. When the decanter bowl rotation speed is increased to 2160 RPM (60% of the maximum operating speed) the MG content in the effluent reaches a maximum of 25110 mg / L. It should also be noted that the MG content is significantly higher than the crude protein in all the samples analyzed. Figure 7 shows that the variation of the fat concentration in the decanter effluent as a function of the increase in the decanter bowl rotation speed follows the same trend observed for solids (ST and SST) because it is their main constituent. The concentration of MG in the effluent increased with the increase of the speed and reached a maximum of 251 10 mg / L at a speed of rotation of the decanter bowl of 2700 RPM (A) and 29870 mg / L at 2880 RPM decanter bowl rotation speed (B). As the speed of rotation of the decanter bowl is further increased, the fat content in the effluent begins to decrease.

The results of these experiments have shown that:

The quality of the shrimp effluent varied only slightly during these experiments.

 The change in the speed of rotation of the decanter bowl did not significantly affect the quality of the recovered organic sludge.

 Increasing the decanter bowl rotational velocity increases solids (ST and SST), crude protein, and fat in the effluent.

 Excessive rotational speed of the decanter can have a negative impact on the extraction of the oil and on the yield of the recovered organic sludge.

 The decanter effluent samples that were collected during operation of the decanter at bowl rotation rates greater than 2700 RPM are not suitable for shrimp oil production because they contain too much solids and protein .

 . The samples that were processed by operating the decanter at a speed of 1800 RPM (the lowest speed tested in this project) are less concentrated in fat despite the fact that their solids and protein contents are perfect for running. the separator.

 The decanter effluent samples that were collected during decanter operation at 2160, 2520

2700 RPM (60, 70 and 75% of the maximum speed, respectively) appear to be the most appropriate for extracting shrimp oil because they contained a good amount of fat and moderate amounts of solids and especially protein . Example 3

Optimization of extraction conditions of astaxanthin-rich shrimp oil from decanter effluent using the separator

 It is important to remember that the decant effluent is the final effluent of the effluent treatment process resulting from the processing of the shrimp before its discharge into the environment. It is also at the level of the decanter that we recover the organic matter which is found in the effluent. Consequently, our goal is to develop a process to extract oil and residual proteins found in the decanter effluent. The extraction of herring oil from its aqueous medium by centrifugation is a process that is already used in the production of flour and herring oil. A used separator was adapted to perform our shrimp oil extraction tests from the decanter effluent. The conditions which most affect the separation of the oil from its aqueous medium are: the centrifugation speed of the effluent;

 . the amount of solids (especially suspended solids) in the effluent;

 . the flow rate of the effluent to be centrifuged; and

 the temperature of the effluent.

Since the speed of operation of the separator can not be varied, all the efforts have focused on the optimization of the other three parameters such as the amount of solids in the effluent, its flow rate and its temperature. input of the separator. Based on the results of the first step, decant effluent samples taken at 2160, 2520 and 2700 RPM bowl rotation rates have been shown to be the most appropriate for recovering oil. they contain because they contain a significant amount of fat while having amounts of solids and moderate proteins. After an exhaustive analysis of all the data available for the preliminary tests, it was decided to extract the shrimp oil from the effluents that come from the decanter at a bowl rotation speed of 2700 RPM. The first test (D) was performed under the following conditions:

1) The decanter bowl rotation speed was 2700 RPM; 2) The decanter effluent was pumped into the separator at a rate of 38 liters per minute (2,280 liters per hour). This flow rate corresponds to 45% of the maximum speed of the pump; and

 3) The effluent was used at room temperature. From this first test D, we were able to successfully extract shrimp oil. By centrifuging 1634 liters of effluent, 18.5 kg of oil was extracted, which represents an average recovery rate of 11.3 grams of oil per liter of effluent. Knowing that the decanter effluent can contain between 24 and 26 g of oil per liter of effluent (see

Table 4), consequently the extraction yield was considered insufficient. Once the 18.5 kg of oil recovered, we visually noticed a bright orange pink coloring of the effluent coming out of the separator, which confirms our conclusion that all the oil that was in the effluent of the decanter had not been totally recovered.

A second test E was carried out the same day and under the same conditions, except that the effluent of the clarifier was heated by adding water vapor. The temperature of the effluent ranged from 80 to 100 ° F. After 20 minutes of operation of the extraction system, a sub-sample of each matrix (decanter effluent, sludge, separator effluent and oil) was taken at 15 minute intervals. This operation was repeated three times to obtain 3 subsamples of each matrix. The 3 sub-samples of each matrix were mixed to obtain a composite sample to obtain more representative samples and to reduce the costs of the analyzes. Samples composed of mud and shrimp oil were used to assess the quality of the finished products obtained during all the experiments of this second stage. Samples composed of decanter effluent (EFF Dec) and separator effluent (EFF Sep) were used to evaluate the efficiency of separator operation. The parameters that have been determined on the composite samples of the decanter and separator effluents are the contents of ST, SST, PB and MG. The results of these analyzes are presented in Table 5. Table 5. Results of the evaluation of the separator efficiency during the experiments of test E.

 Optimization of the separator (test E)

From the results of the analyzes presented in Table 5, it is noted that the decanter effluent is very rich in suspended solids, which consist mainly of fat and protein.

By observing the results of Table 5, we can see that there is a small contradiction between the quantities recovered from ST (17086 mg / L) and SST (19200 mg / L). This contradiction shows us that despite our efforts to prepare composite samples from 3 subsamples, the decanter and separator effluents remain very heterogeneous and difficult to analyze. Based on the results of analyzes obtained, it can be seen that a minimum of 15585 mg of shrimp oil per liter of effluent was recovered at the time of sampling. . During this experiment, by centrifuging 2635 liters of effluent, 46 kg of oil was extracted, which represents an average recovery rate of 17457 mg of oil per liter of centrifuged effluent. . This experiment also demonstrated that raising the decanter effluent temperature to between 80 and 100 ° F increased the oil recovery rate. In order to further improve the extraction efficiency of the oil, it was therefore decided to do another experiment, but this time heating the effluent to a higher temperature.

Consequently, a third experiment at the plant was carried out (F), this time using the decanter effluent heated to 175 ° F while retaining the other constant parameters such as the rotation speed of the bowl of the decanter at 2700 RPM and pumping the effluent into the separator with a flow rate of 38 liters per minute. The results of this experiment are presented in Table 6.

Table 6. Results of the evaluation of separator efficiency during experiment F.

The results of the analyzes demonstrated that the rise in the temperature of the decanter effluent greatly improved the recovery efficiency of ST, SST and MG. The results of the analyzes are consistent and confirm that during this test and at the time of sampling (that is, the extraction system operated for 1 hour), a minimum of 25680 mg d was recovered. oil per liter of effluent. During this experiment (F), by centrifuging 2350 liters of effluent, 43.5 kg of oil were extracted, which represents an average recovery rate of 1851 mg of oil per liter of centrifuged effluent. This demonstrates an improvement in the extraction yield compared to that obtained in test E (17457 mg of oil per liter of effluent), but lower than that estimated in the laboratory (25680 mg of oil per liter of effluent). It is normal that the estimated yield in the laboratory is higher than that actually obtained once the extraction process at the plant is complete, because the effluent composite samples used to determine the extraction yield were taken at the time that the operation of the extraction system equipment was stabilized, this can probably lead to overestimation of performance. In addition,

 The operation of the separator is disturbed periodically during solids evacuation, which may also have a downward influence on the efficiency. Nevertheless, this test has demonstrated that raising the Peffluent temperature to 175 ° F is a significant parameter that can improve shrimp oil extraction efficiency. Consequently, the operating conditions of the extraction system 0 used in this test for extracting the oil were considered

 satisfactory for their application on a larger scale.

The fourth test G was carried out while trying to apply the same conditions as those used in the test F. The objective of this test G was the evaluation of the operation of the shrimp oil extraction system. in large scale. During this experiment it was not possible to heat the effluent to the expected temperature of 175 ° F because of a large production volume. The temperature of the effluent reaches only 140 ° F. The extraction system operated in continuous mode and the decanter effluent was directly introduced into the separator with a variable flow rate between 38 and 46 liters per minute. The samples were taken for laboratory analysis and 0 the total volume of the centrifuged effluent as well as the total amount of recovered oil were measured at the plant to evaluate the yield. The results of this test are presented in Table 7.

Table 7. Results of the evaluation of separator efficiency during experiment G.

Estimated recovery at the plant: 363 kg of oil / 36,015 liters of effluent or 10,079 mg of oil per liter of effluent

 The density is 0.931 kg / L; (363 kg / 390 liters)

The results obtained during this large-scale experiment did not live up to our expectations. The extraction yield estimated in the laboratory was only 13575 mg of oil per liter of effluent. The yield obtained at the plant was not better and confirmed this decrease compared to that obtained during the test F. It was on average 10079 mg of oil per liter of centrifuged effluent while that obtained during the test F was on average 1851 1 mg of oil per liter. In order to explain this decrease in yield, the results of the analyzes shown in Table 7 were examined with more attention. They show that the decanter effluent contained about the same amounts of solids as those treated in previous tests. On the other hand, the amount of crude protein was higher while that of fat was less. In addition, it was noted that during this large scale test (36,015 liters), the operation of the separator was disturbed due to the solids evacuation problem. The separator was cleaned and a final test H was carried out in order to re-evaluate the oil extraction yield, but this time by treating a small amount of effluent (small scale treatment) while trying to apply the same conditions as those used in test G. The decanter effluent was heated to 140 ° F and pumped into the separator with a variable flow rate between 38 and 46 liters per minute. The results obtained during this test are shown in Table 8.

Table 8. Results of the evaluation of separator efficiency during experiment H.

Reduction / recovery 27,945 26,350 22,100 4006

Estimated recovery at the plant: 48 kg of oil / 2,344 liters of effluent or 20,478 mg of oil per liter of effluent

 The density is 0.923 kg / L; (48 kg = 52 liters)

The results of laboratory analyzes demonstrated that during this test 22100 mg of oil per liter of effluent could be extracted. The factory performance evaluation confirmed the good operating efficiency of the small-scale extraction system. On average, 20478 mg of oil per liter of centrifuged effluent was extracted, although the decanter effluent contained larger amounts of solids, crude protein and fat than in previous tests. This result shows that

 Extraction system equipment is suitable for the treatment of an average volume of effluent, that is to say when the extraction system operates over a short period of time. In order to treat large volumes of effluent, ie when the extraction system is operating in continuous mode over a long period of time, it would probably be necessary to decrease the speed of rotation of the decanter bowl in order to have an effluent less loaded with solids, which can facilitate the evacuation of solids accumulated in the separator and thus improve the extraction efficiency of the oil. The results obtained during these tests allowed to determine the parameters to have a good operation of the separator and thus obtain a good oil extraction yield:

1. The decanter bowl rotation speed can be decreased to 2520 RPM (a decant operation rate equal to 70% of its maximum speed) and even up to 2160 RPM (60% of maximum speed) in order to have a less solid effluent and thus avoid their accumulation in the separator.

 2. The effluent must be pumped into the separator at a rate of 38 to 46 liters per minute or 2280 to 2760 L / hour (a pump operating speed between 45 and 55% of its maximum flow).

3. The decanter effluent must be preheated to a minimum temperature of 140 ° F using steam. (Ideally the decanter effluent should be preheated to 95 ° C using the heat exchanger). 4. To produce this oil on a large scale it will be necessary to acquire 1) a separator more adapted to this process and 2) the heat exchanger to preheat the effluent of the decanter to a temperature 95 ° C

 Example 4

5 Characterization of the products obtained

 Characterization of recovered oil

 The total fatty acid profile was determined on each sample of shrimp oil extracted during experiments E, F, G, H in order to evaluate its quality. The results of this profile are presented in Table 9. 0

Total fatty acid profile of shrimp oil extracted during

C24: 1 0.30 0.28 0.28 0.27 0.28 0.34 0.02

C18: 2n6 0.73 0.81 0.81 0.87 0.81 0.97 0.06

C20: 2n6 0.30 0.30 0.22 0.24 0.26 0.31 0.04

C22: 2n6 0.00 0.00 0.00 0.00 0.00 0 0.00

C18: 3n6 0.00 0.00 0.00 0.00 0.00 0 0.00

C18: 3n3 0.59 0.60 0.67 0.79 0.66 0.79 0.09

C20: 3n6 0.15 0.13 0.13 0.14 0.14 0.17 0.01

C20: 3n3 0.12 0.12 0.11 0.12 0.12 0.14 0.01

C18: 4n3 1, 27 1, 38 1, 45 1, 56 1, 41 1J 0.12

C20: 4n6 0.42 0.47 0.36 0.35 0.40 0.48 0.06

C20: 4n3 0.37 0.33 0.31 0.30 0.33 0.40 0.03

C22: 4n6 0.19 0.20 0.19 0.17 0.19 0.23 0.02

C20: 5n3 (EPA) 8.87 8.77 8.49 8.45 8.64 10 0.21

C22: 5n6 0.15 0.16 0.05 0.11 0.12 0.14 0.05

C22: 5n3 0.46 0.46 0.35 0.35 0.40 0.48 0.06

C22: 6n3 (DHA) 7.83 7.56 8.28 8.55 8.05 9.6 0.44

Total 83.55 83.07 82.68 84.83 83.53 100 0.94

Saturated 18.57 19.06 18.99 19.01 18.91 23 0.23

Mono unsaturated 43.52 42.71 42.27 43.85 43.09 52 0.73

Polyunsaturated 21, 45 21, 29 21, 43 21, 97 21, 54 26 0.30

Total fat 87.27 86.77 86.36 88.60 87.25 0.97

Omega-3 19.51 19.22 19.66 20.10 19.62 23 0.37

Omega-6 1, 94 2.08 1J7 1, 87 1, 91 2.3 0.13

The results in Table 9 demonstrate that the fatty acid profile contained in the oil is similar in all the samples extracted during the experiments. The recovered oil is of good quality because it contains a large amount of acids Omega-3 (23%), including 10% EPA (Eicosapentaenoic Acid Methyl Ester) and 9.6% DHA (Docosahexaenoic Acid Methyl Ester). In addition, the analyzes performed on these samples demonstrate that the oil obtained contains no trace of moisture. This oil can therefore be a food additive with very

 advantageous, inter alia for its incorporation into aquaculture feeds and especially those for salmonids.

Physico-chemical characterization of recovered organic sludge

 Samples of the organic sludge recovered after decanting during the experiments were analyzed to determine their moisture content, total solids, fat, crude protein and ash. The results of these analyzes are presented in Table 10.

Table 10. Results of analyzes of samples composed of mud recovered during the experiments, E, F, G and H.

From the results of the analyzes in Table 10, it can be seen that the chemical composition of the sludge is constant for all the samples taken during the experiments. They consist of an average of 82, 14 ± 0.72% moisture and 17.86 ± 0.72% total solids. The total solids consist on average of 1.98 ± 0.45% fat, 1 1, 30 ± 0.48% crude protein and 3.27 ± 0.53% ash. These results indicate that the extraction of the oil did not affect the quality of the sludge recovered during these tests because its chemical composition is comparable to that obtained during the previous tests.

In order to evaluate the quality of the fat contained in the recovered sludge, the total profile of the fatty acids was carried out. The results of this profile are shown in Table 11.

Table 11. Total profile of fatty acids contained in the mud recovered from the decanter during experiments E, F, G and H.

C18: 3n3 0.02 0.03 0.02 0.02 0.02 0.73 0.00

C20: 3n6 0.00 0.00 0.00 0.00 0.00 0 0.00

C20: 3n3 0.00 0.01 0.00 0.00 0.00 0 0.00

C18: 4n3 0.04 0.04 0.04 0.04 0.04 1.5 0.00

C20: 4n6 0.03 0.04 0.03 0.03 0.03 1, 1 0.00

C20: 4n3 0.01 0.01 0.01 0.01 0.01 0.36 0.00

C22: 4n6 0.00 0.01 0.00 0.01 0.00 0 0.00

C20: 5n3

 0.39 14

(EPA) 0.38 0.42 0.40 0.38 0.02

C22: 5n6 0.00 0.00 0.00 0.00 0.00 0 0.00

C22: 5n3 0.01 0.02 0.01 0.01 0.01 0.36 0.00

C22: 6n3

 0.33 12

(DHA) 0.33 0.35 0.33 0.31 0.01

Total 2.71 3.06 2.66 2.51 2.74 100 0.23

Saturated 0.66 0.72 0.63 0.59 0.65 24 0.05

Mono

 1, 19 43

unsaturated 1, 17 1, 38 1, 13 1, 07 0.13

Poly-

0.90 33

in saturated 0.88 0.97 0.89 0.85 0.05

Total fat 2.83 3.20 2.77 2.63 2.86 100 0.24

Omega-3 0.81 0.87 0.81 0.77 0.82 30 0.04

Omega-6 0.07 0.10 0.08 0.08 0.08 2.9 0.01

The results presented in Table 11 demonstrate that the total profile of the fatty acids contained in the sludge is similar for all the samples recovered during the experiments E, F, G and H. The fat content in the sludge is very good quality. It contains a large amount of Omega-3 acids (30%), including 14% EPA (Eicosapentaenoic Acid Methyl Ester) and 12% DHA (Docosahexaenoid Acid Methyl Ester), which play an important role in nutrition. It is important to point out that the mud recovered has a slight dull pink hue which testifies to the presence of a carotenoid pigment, which adds value to its

incorporation in animal nutrition and especially in aquaculture feeds.

Example 5

Summary of conditions

In order to obtain more oil and less protein in the shrimp effluent without affecting the quality of the recovered organic sludge, the optimum conditions of the horizontal two-phase centrifuge (settler) were established. The speed of rotation of the decanter bowl is a parameter that has a great influence on the separation of solids from the liquid. Experiments were conducted to evaluate the efficiency of the decanter operation at 7 different rotational speeds of the bowl. Variations in shrimp processing effluent quality and DAF efficiency were also evaluated. The results of these experiments have shown that:

The quality of the shrimp effluent varied slightly during these experiments. The content of total suspended solids (SST) varied between

1404 and 2191 mg / L, while those of total nitrogen (400 to 462 mg / L), crude protein (2500 to 2890 mg / L) and fat (1013 to 1099 mg / L) did not vary significantly. .

 . The reduction percentages of SST (78 to 85%), TKN (28 to 32%), PB (28 to 32%) and MG (60 to 69%) in the shrimp processing effluent demonstrate that the system DAF works with the same efficiency that was achieved during the months of September and October 2005 after its optimization was finalized

 • Changing the speed of rotation of the decanter bowl does not significantly affect the quality of the recovered organic sludge.

 . Increasing the speed of rotation of the decanter bowl increases solids (ST and SST), crude protein and fat in the effluent.

The decanter effluent samples that were taken during the operation of the decanter at bowl rotation speeds greater than 2700 RPM (75% of maximum speed) is not suitable for the production of shrimp oil because they contain too much solid and protein. The samples that were processed by operating the decanter at a speed of 1800 RPM (the lowest speed tested in this project) are less concentrated in fat despite the fact that their solids and protein contents are perfect for running. the separator.

 The decanter effluent samples that were collected during decanter operation at bowl rotation speeds of 2160, 2520 and 2700 RPM (60, 70 and 75% of maximum velocity, respectively) appear to be the most appropriate extraction of shrimp oil because they contained a good amount of fat and moderate amounts of solids and especially protein.

[00101] The optimization of the extraction process of the oil which is in the decanter effluent using the separator has established that:. The decanter effluent must be preheated to a minimum temperature of 140 ° F using water vapor (ideally the decanter effluent must be preheated to 95 ° C using heat exchanger).

 . The effluent must be pumped into the separator at a rate of 38 to 46 liters per minute or 2280 to 2760 L / hour (a pump operating speed between 45 and 55% of its maximum flow).

 The decanter bowl rotation speed can be decreased to 2520 RPM (a decant operation rate equal to 70% of its maximum speed) and even up to 2160 RPM (60% of the maximum speed) in order to have Effluent less loaded solids and thus prevent their accumulation in the separator. · By observing the parameters indicated above, it is possible to extract on average 20478 mg of oil per liter of effluent.

 To produce oil on a large scale it is necessary to acquire 1) a more suitable separator for this process and 2) a heat exchanger for preheating the decanter effluent at a temperature of 95 ° C.

[00102] The optimization of the operation of the clarifier and the separator made it possible to recover organic sludge and shrimp oil. The results of the analyzes Organic sludge and oil recovered from shrimp effluents revealed that:

The sludge recovered after the decanter contains on average 17.86 ± 0.72% of total solids which consist of 1.98 ± 0.45% fat, 11.30 ± 0.48% crude protein and 3, 27 ± 0.53% ash. The fat contained in the mud is of very good quality. It contains a large amount of Omega-3 acids (30%), including 14% EPA (Eicosapentaenoic Acid Methyl Ester) and 12% DHA (Docosahexaenoic Acid Methyl Ester), which plays an important role in nutrition. It is important to note that the recovered mud has a slight dull pink hue, which indicates the presence of a carotenoid pigment, which adds value to its incorporation into aquaculture feeds. The results of freeze-dried organic sludge analyzes, referred to as Organic Shrimp Solids (SOC), are shown in Table 12.

The shrimp oil obtained is very rich in omega-3 fatty acids and astaxanthin (Table 12), a carotenoid pigment that is responsible for the orange-pink coloring of the flesh of salmonids and crustaceans (crab, shrimp, lobster). In addition, the total fatty acid profile shows that the extracted shrimp oil is of high quality because it contains a large amount of Omega-3 acids (23%), including 10% EPA (Eicosapentaenoic Acid Methyl). Ester) and 9.6% DHA (Docosahexaenoic Acid Methyl Ester). In addition, the oil obtained contains no trace of moisture. This oil can therefore be a food additive with very advantageous characteristics, among others for its incorporation into aquaculture feeds and especially those for salmonids.

T leau 12: Characteristics of organic shrimp solids and shrimp oil

Example 6

Study of the Effect of Temperature on the Separation of Organic Shrimp Solids (SOC) and Shrimp Oil Using the Decanter

The shrimp processing method comprises several stages (cooking, cooling, dehulling, inspection, brining, dripping, freezing, etc.) and requires a very large amount of drinking water. The water used during the Shrimp production (EPC) contains fats and proteins. EPC is used as a raw material in our new process for extracting shrimp oil (HC) and organic shrimp solids (SOC). Water leaving the shrimp processing process (EPC) is first collected in a tank (R1) and then pumped into a dissolved air flotation system (DAF). The EPC temperature can vary between 10 ° C and 17 ° C. In the DAF system, solids, compounds

mainly protein, fat and minerals (ash), are collected by a procedure called "skimming" or "skimming". Recovered solids, called skimmings (SKIM), are collected in a second tank (SKIM R 2) and pumped into the decanter which separates them into two phases: a solid phase, called organic shrimp solids (SOC) and a phase liquid, called decanter effluent (EFF DEC). The efficiency of the separation and the chemical composition of SOC and EFF DEC depend on several variables, but the temperature of the SKIM is the main parameter that affects the mobility of the oil. The objective of this study was therefore to determine the temperature of the SKIM and the speed of the bowl rotation of the decanter which make it possible to obtain the EFF DEC richest in oil.

In a first test, 1810 L SKIM were accumulated in the tank R2. The SKIM was heated to a temperature of 85 ° C with addition of steam. The SKIM (85 ° C) were then pumped into the decanter at a rate of 50 L / min. The decanter was operated at 3 different speeds: 65% (2520 RPM), 75% (2700 RPM), and 100% (3240 RPM) of its maximum speed. A second test was carried out under the same conditions but at a SKIM temperature of 10 ° C (natural temperature of production water). During these experiments, samples of SKIM, SOC and EFF DEC were taken to analyze the concentrations of total solids (TS), ash, crude protein (PR) and fat (MG). The results of these analyzes are presented in Table 13.

Table 13: Anal of samples taken during tests at 85 ° C and 10 ° C

Composition of the decanter effluents (EFF DEC)

 The results obtained during the tests at 85 ° C and 10 ° C showed that the temperature SKIM greatly affects the composition of EFF DEC and SOC. At 10 ° C, recovered EFF DEC contains more solids than 85 ° C. Ash values are very likely to be affected, while protein concentrations increase from 1319, 1313 and 1063 mg / L (10 ° C) to 2579, 3694 and 5106 mg / L (85 ° C), for decanter speeds 65, 75 and 100%, respectively.

[00106] Figure 8 clearly demonstrates that the temperature has a considerable effect on the concentration of fat (oil) contained in the decanter effluents. At 85 ° C, the recovered effluent had a fat concentration of 148, 96 and 126 mg / L, while at 10 ° C the concentrations were 6070, 1370 and 14880 mg / L, decanter of 65, 75 and 100%,

respectively. [00107] Figure 9 demonstrates the effect of the temperature and the speed of the settler on the concentration of total solids recovered. At 85 ° C, decanter velocity appears to have little effect on the total solids concentration of 15610, 15510 and 15580 mg / L for decanter speeds of 65, 75 and 100%, respectively. The results obtained at a temperature of 10 ° C demonstrate the effect of the decanter velocity, or we obtain concentrations of 21340, 27720 and 31790 mg / L for decanter speeds of 65, 75 and 100%.

The results clearly demonstrate that a lower temperature SKIM allows to obtain a decanter effluent richer in organic matter and particularly richer in oil. Composition of Recovered Shrimp Organic Solids (SOC)

 [00109] The total solids contained in the SKIM coming from the DAF system are distributed in the liquid and solid phases. Figure 10 demonstrates the effect of temperature as well as decanter velocity on SOC composition. It is interesting to note that the trends are the opposite of those observed for effluents. At 85 ° C, SOCs are higher in fat, with values of 12.4, 15.0 and 15.7% for decanter speeds of 65, 75 and 100%, respectively. At a temperature of 10 ° C, we obtain 3.6, 3.4 and 3.0% concentrations for the same decanter speeds. The same trend is observed for total solids and proteins.

The temperature greatly influences the fat concentration of the effluents and solids. However, since only two temperatures were selected for these tests, a second experiment was conducted at intermediate temperatures. This second experiment follows the results obtained during the first experiment in order to determine the temperature of the SKIMs which make it possible to obtain the decanter effluent (EFF DEC) the richest in oil. Intermediate temperatures of 10 ° C, 30 ° C, 40 ° C and 60 ° C were selected and the decanter operated at 75% of its maximum speed (2700 rpm). These tests were carried out under the same conditions as the previous tests. The SOC and EFF DEC samples were taken to analyze the total solids (TS), crude protein (PR) and fat (GM) concentrations. The results of these analyzes are presented in Table 14.

Table 14: Analysis of EFF DEC and SOC samples for different temperatures; decanter at 2700 rpm.

Effect of temperature on the composition of the decanter effluent (EFF DEC)

[00112] Figure 11 demonstrates the effect of temperature on the total solids and fat concentration of decanter effluents (EFF DEC). It is interesting to note the increase in fat concentration from 7870 mg / L to 1500 mg / L when the temperature is raised from 10 ° C to 30 ° C. This represents an increase of 42%. We can also see that the fat concentration reaches a maximum value at 30 ° C and then decrease and reach a minimum value at 60 ° C. A similar, though less marked, trend is observed for total solids concentration as a function of temperature. This demonstrates that the migration of fat to the liquid phase (the effluent) is favored at a temperature of about 30 ° C. Effect of temperature on the composition of organic shrimp solids (SOC)

 In Figure 12, the effect of temperature on the fat composition and total solids of SOCs is demonstrated. In both cases, an upward trend, almost linear, is obtained, contrary to what is observed for the decanter effluent. It therefore seems that a higher temperature favors the recovery of organic solids (SOC) rather than the recovery of the oil.

Conclusion

This study has demonstrated that: a) the increase of the temperature of the "SKIM" at about 30 ° C makes it possible to obtain a decanter effluent richer in the oil; and b) Increasing the temperature of the "SKIM" to about 85 ° C provides organic shrimp solids that are higher in fat and protein.

 Example 7

 [00115] Development of process for the production of shrimp oil and organic shrimp solids (SOC) based on the water used in the processing of shrimp.

[00116] Multiple studies at the laboratory scale and at the pilot plant scale allowed us to develop the process for manufacturing the new water-based products used in shrimp processing to obtain a rich shrimp oil. astaxanthin and organic shrimp solids (SOC).

[00117] Figure 1 shows the scheme of the process of manufacturing shrimp oil and organic shrimp solids (SOC) water-based used in the processing of the shrimp. Our new industrial-scale process involves several steps and requires the following equipment parts: Tank # 1: This tank is used to accumulate all the effluents from the shrimp processing process. The flow rate of the effluent leaving this tank is about 2000 l / min. The effluent contains about 1.8% solids. It must be stainless steel and isolated from the outside environment.

Dissolved Air Flotation (DAF) Basin: The DAF system is a process that uses small air bubbles that attach to solid particles. These particles rise to the surface where they are picked up by a skimming device. The solids recovered at this stage are called "skimmings" and contain about 6% organic solids and 94% water. The flow of "skimmings" is 60-90 L / m

Tank # 2: The tank * 2 is used to accumulate the skimmings recovered from the DAFs of the flotation tanks. Tank # 2 must be stainless steel and equipped with a mixer, in order to keep the solution homogeneous.

Pump # 1: This is a pump that is used to transfer "skimmings" from tank # 2 to heat exchanger # 1. The flow of "skimmings" is about 60-90 L / min. Heat exchanger # 1 (EC1): The heat exchanger is used to heat the skimmings before they go into the centrifugal decanter. This heat exchanger must be able to rapidly raise the temperature of skimmings a) from 10 ° C to 85 ° C to improve the production of SOC (quality, yield and profitability), b) from 10 ° C to 30 ° C to improve the production of shrimp oil

Decanter centrifuge (DEC): The decanter is used to separate the solid phase (SOC) and the liquid phase (effluent from the decanter) which contains the oil.

Tank # 3: Tank # 3 is used to accumulate the decanter effluent. It must be stainless steel and equipped with a mixer, in order to maintain the homogeneous solution.

Pump # 2: Pump # 2 is the same pump style as Pump # 1. It is used to transfer effluent from Tank # 3 to the second heat exchanger. Its flow will be about 50-60 l / min.

Heat Exchanger # 2 (EC2): The process of extracting shrimp oil requires two heat exchangers because there are two different operations that need it at the same time. This piece of equipment will be used to heat the decanter effluent to 90 ± 5 ° C.

Separator (SEP): The separator is a vertical centrifuge. This device is capable of separating the effluent from the decanter in three phases: shrimp oil, SOC and effluent from the separator which contains very few solids.

Claims

1. A process for extracting oil of marine origin, comprising:

(a) obtain treatment effluent from a marine organism;

b) add a flocculant to the treatment liquid of a) and separate an aqueous phase from the surface flocculated solids to recover said solids;

c) separating said solids recovered in b) into a solid phase and a liquid phase and recovering the solid phase and/or the liquid phase;

d) subjecting the liquid phase obtained in c) to vertical centrifugation to obtain an aqueous phase and an oil; And

e) recover the oil thus separated.

2. The method according to claim 1, where:

b) the separation of said liquid phase from said surface flocculated solids is carried out with a dissolved air flotation (DAF) system;

c) the separation of said flocculated solids in b) into a solid phase and a liquid phase is carried out using a 2-phase horizontal centrifuge (settler); And

d) obtaining the aqueous phase and the oil is carried out by subjecting the liquid phase obtained in c) to vertical centrifugation (separator).

3. The process according to claim 1 or 2, also comprising the following step: f) the solid phase recovered in c) is then dried to constitute a solid residue enriched in proteins.

4. The process according to claim 1, 2 or 3, where the treatment liquid obtained in step a) is at a temperature of approximately 4 to 25°C before proceeding to step b) (particularly between 8 and 20°C, more particularly between 10 and 18°C).

5. The process according to claim 1, 2 or 3, where the solid phase obtained in step b) is heated to approximately 20 to 40°C before proceeding to step c) (particularly between 25 and 35 °C, more particularly around 30°C).

6. The process according to claim 1, 2 or 3, where the liquid phase obtained in step c) is heated to a temperature of approximately 80 to 99°C before proceeding to step d) (particularly between 85 and 98°C, more particularly around 95°C).

7. The method according to claim 2, where the decantation in step c) is carried out at a bowl rotation speed between 1800 and 3300 rpm (particularly between 2000 and

2900 rpm, more particularly between 2500 and 2800 rpm).

8. The method according to one of claims 1 to 7, where the marine organism is chosen from: crustaceans and fish.

9. The method according to claim 8, where the crustacean is chosen from: krill, shrimp, rock crab, snow crab, spider crab and lobster.

10. The method according to claim 9, where the crustacean is shrimp.

11. The method according to one of claims 1 to 10, where the treatment liquid is chosen from: cooking water, cooling, rinsing, washing, shelling, brining, draining.

12. An oil as obtained by the process according to one of claims 1 to 11.

13. A crustacean oil comprising more than 800 pg/g (more particularly more than 1000 pg/g of astaxanthin).

14. Oil as defined in claim 12 or 13, mainly coming from shrimp.

15. A solid residue as obtained by the process according to claim 1 or 11.

16. A solid residue of marine organism comprising: more than 60% protein; more than 400 pg/g of vitamin E; more than 4000 IU/100g of vitamin A; and more than 350 pg/g of astaxanthin.

17. The residue as defined in claim 15 or 16, mainly coming from shrimp.

18. The use of an oil as defined in claim 12, 13 or 14 as a food additive in an aquaculture feed.

19 The use of an oil as defined in claim 12, 13 or 14 for the production of a food or a food supplement.

20. The use according to claim 19, or the food or food supplement is intended for human, animal, aquaculture or poultry use.

21. The use of a residue as defined in claim 15, 16 or 17, as a food additive in an aquaculture feed.

22. The use of a residue as defined in claim 15, 16 or 17, for the production of a food or a food supplement.

23. The use according to claim 22, or the food or food supplement is intended for human, animal, aquaculture or poultry use.

24. A composition comprising an oil as defined in claim 12, 13 or 14, mixed with an excipient.

25. The composition according to claim 24 where the excipient is a protein-enriched flour.

26. The use of a residue as defined in claim 15, 16 or 17, as a food additive in animal feed.

27. A feed intended for feeding at least one fish raised in fish farming, said feed comprising an oil as defined in claim 12, 13 or 14.

28. A feed intended for feeding at least one fish raised in a fish farm, said feed comprising a solid residue as defined in claim 15, 16 or 17.

29. A method for feeding fish raised in a fish farm, said method comprising the administration of the feed as defined in one of claims 27 and 28.

30. A food supplement comprising an oil as defined in claim 12, 13 or 14 mixed with an excipient physiologically acceptable in animals.

31. A food supplement comprising a solid residue as defined in claim 15, 16 or 17 mixed with an excipient physiologically acceptable in animals.

32. The food supplement according to claim 30 or 31, where the animal is a human.

33. The food supplement according to claim 30 or 31, where the animal is a pet.

34. The food supplement according to claim 30 or 31, where the animal is a farm animal.

35. The food supplement according to claim 30 or 31, where the animal is a bird.

36. A method for combating free radical oxidation in animals, said method comprising the administration of an effective dose against the oxidation of the food supplement as defined in one of claims 30 and 31.

37. The method according to claim 36, where the animal is a human.

38. The method according to claim 36, wherein the animal is a pet.

39. The method according to claim 36, where the animal is a farm animal.

40. The method according to claim 36, where the animal is a bird.