CN1068145A - " low temperature highly basic " improves sulfurous method cane sugar manufacture cleaning technique - Google Patents

Abstract

The present invention proposes a kind of purification effect height for improving sulfurous method sugaring cleaning technique, can obviously improve the White Sugar Quality of sulfurous method production and the cleaning technique novel method of the rate of recovery.Be on the basis of sulfurous method cleaning technique, to have increased high-alkali (pH=11) removal of impurities and the auxiliary clarification of phosphoric acid flow process.Adopted two iso-electric points, pH11 and 7 is through drifting along and precipitating twice and separate, to reach the purpose of efficient impurity removal.Implement this technical process and increase equipment such as floating device in the peace and quiet workshop section of former sulfurous method, reduced investment, peace and quiet effect is: the average 2154ICUMSA of color value of clear juice, turbidity is average 737, and the colloid clearance reaches 53.8%, and purity improves AP+3.64, GP+2.73.

Description

" low temperature highly basic " improves sulfurous method cane sugar manufacture cleaning technique

The invention belongs in the cane sugar manufacture industry, strengthen the novel method of sulfurous method cleaning technique.

Cane sugar manufacture industrial production arable land white sugar generally adopts two kinds of methods, i.e. carbonatation process and sulfurous method.The cleaning technique of carbonatation process is to utilize the high basicity of a carbon full charge to remove a large amount of non-sugars, two carbon full charges are removed CaO and nonsugar remaining in the sugarcane juice, be characterized in utilizing milk of lime and carbonic acid gas to make finings, with three iso-electric point (PH11, PH8.2-8.4 PH7) separates with twice whole-juice filtering.The White Sugar Quality that this method is produced is better, but complex process, facility investment height, consumes amount of lime and Duo ten times approximately than sulfurous method, has the problem of filter mud serious environment pollution.Its technology is seen flowchart 2.The cleaning technique of sulfurous method is to introduce SO on the basis of lime method ₂, utilize milk of lime and sulfurous gas to make finings, this method technology is simple, reduced investment, only with an iso-electric point (PH7) flash liberation (post precipitation filtration mud juice) removal of impurities.But non-sugared impurity and the pigment that can remove are few, and sugarcane juice purity improves little, are generally ± 0.5GP, the easy flavescence of color during commerieal sugar is stored, and the sugar part rate of recovery is low.For a long time, international and domestic all have many people seeking to improve the peace and quiet novel process of sulfurous method, but all different with the present invention, and do not see to drop into and use.

The present invention is low for remedying the sulfurous method purification effect, removes the weak shortcoming of organic impurity ability and to propose a kind of purification effect height, less investment, cost low, can obviously improve the White Sugar Quality that sulfurous method produces and the cleaning technique novel method of the rate of recovery.(seeing process flow sheet three)

The novel method of cleaning technique is to adopt the PH11 of carbonatation process sugaring cleaning technique, two iso-electric points of PH7 of sulfurous method sugaring cleaning technique, twice removal of impurity.On the sulfurous method basis, increase the auxiliary clarification of a high-alkali removal of impurities and phosphoric acid flow process, it is a kind of method of strengthening the sulfurous method cleaning technique.Owing to increased by one section flow process, also increased an essential equipment-floating device.The mixing juice that comes out from squeezing is 7-8 through giving grey processing controls PH; And give add phosphoric acid 100-150PPm(phosphoric acid amount to the sugarcane amount than) above-mentioned mixing juice enters peace and quiet workshop through once being heated to 50-60 ℃, after whisking machine is got blisters " adding milk of lime makes the pH value of mixing juice reach 11; add phosphoric acid 100-200PPm(phosphoric acid amount afterwards to sugarcane amount ratio in the phosphoric acid mixing tank) and flocculation agent (using T type polyacrylamide) 3PPm; by entering floating device behind the static mixer; make the above-mentioned main lye that has reacted carry out dissolved air flotation; scum silica frost is drained by floating device top; isolated juice is gone into lower floor's sedimentation, settlement separate be clear juice once, the stove drying that once clear juice enters the sulfurous method cleaning technique then, neutralization, the subsider juice that second-heating obtains through precipitate and separate after 98-105 ℃ again is the clear juice of secondary.From through the mixing juice that gives processing to drawing once, the clear juice of secondary is exactly the complete peace and quiet flow process of the present invention.Be not difficult to find out that its technical characterictic is, has increased the auxiliary clarification of high-alkali (PH=11) removal of impurities and phosphoric acid flow process on the basis of sulfurous method cleaning technique.Two iso-electric point: PH11 and 7 have been adopted, through drifting along and precipitating twice and separate, to reach the purpose of efficient impurity removal.

Accompanying drawing is that " low temperature highly basic " improves sulfurous method cleaning technique flow process, setting drawing 1

Among the figure: (2) well heaters of (1) mixed juice case (3) milk of lime buckets (4) whisking machines (5) phosphoric acid buckets (6) phosphoric acid mixing tanks (7) give once clear juice case (12) stove drying neutralizer (13) second heater (14) settling bowl (15) subsider juice (the clear juice of secondary) case (16) scum silica frost mud juice thermotank (17) vacuum suction filter of flocculation tower (8) flocculation agent case (9) static mixer (10) floating device (11).

Technology of the present invention is achieved in that the mixing juice that will squeeze out is (about 80AP, 20 ° of BX) in (1), add in advance earlier pH value that milk of lime makes mixing juice reach 7-8 And add phosphatase 11 00PPm(phosphoric acid and sugarcane than) afterwards, be pumped into well heater (2), once heat, temperature is 50-60 ℃.This temperature is lower than a Heating temperature of former sulfurous method cleaning technique.If once Jia Re temperature is higher than 60 ℃ and can makes down the step add milk of lime and cause a large amount of ruined adverse consequencess of reducing sugar under the PH11 highly basic condition, be difficult to absorb SO in the time of also stove drying can being influenced ₂; If once Jia Re temperature is lower than 50 ℃, not only speed of response is too slow but also Ca(PO ₄) ₃Precipitation is incomplete, and impurity-eliminating effect Cha ， And causes the serious consequence of evaporating pot fouling; So controlled temperature is good with 55 ℃.Hot mixing juice enters whisking machine (4), has two to add inlet in (4) ingress; One is that main ash adds inlet, promptly, milk of lime flows out from milk of lime bucket (3), in (4) preceding adding sugarcane juice, controls its add-on, makes the mixing juice pH value bring up to 11, (PH11 is the best iso-electric point of removing non-sugared impurity in the sugarcane juice).Another mouthful adds inlet for pressurized air, in order to add an amount of pressurized air, increases air capacity in the sugarcane juice, makes sugarcane juice enter the separation of fully floating in the floating device, reach based on floating, and be auxilliary to sink, the bonded that drifts along separates purpose substantially.Mixing juice is after main ash adds an amount of pressurized air to PH11 And, and the bubble that thorough mixing ， And is big with diameter in whisking machine (4) chops up, to satisfy the needs of next step " come-up ".On whisking machine (4) outlet conduit, be provided with a static phosphoric acid mixing tank (6), pH value is modulated come out to 11 mixing juice (claiming main lye) from (4) enter (6) before by phosphoric acid bucket (5) be pressed into 100-200PPm(to sugarcane than) industrial phosphoric acid (20 times of 85% industrial phosphoric acid dilute with waters), enter (6) thorough mixing, continue afterwards to flow to that to give flocculation tower (7) purpose be to allow main lye have the certain reaction time to allow calcium phosphate fill fractional precipitation And adsorb non-sugar impurity and pigment in the sugarcane juice in a large number as heavy clear agent.Then by flocculation agent case (8) to liquid stream add 3PPm(to sugarcane than) flocculation agent, make the contaminant particles bridging in the sugarcane juice become the bigger agglomerate throw out of volume, changed the volume of suspended substance particle, utilize the adhesive power of bubble and particle to increase buoyancy lift, buoyance lift speed is beneficial to the separation of drifting along.Floating device (10) is the garden cylindricality open container at a band awl end, is divided into three layers: the upper strata is the come-up layer, following two-layer be settled layer.Flow to through the effusive liquid of static mixer (9) that (the floating layer of 10 〕 And is left alone without help to stay about 15-20 minute into floating device thereon.Scum silica frost is gone up the removal of warp float scraper plate naturally and is sent into scum silica frost mud juice thermotank (16) along the scum silica frost ring; Clear juice changes lower floor's sedimentation over to through level control box; The mud juice of come-up layer bottom enters the bottom from central downtake and puts into scum silica frost mud juice thermotank (16) in the lump with the bottom mud juice, and scum silica frost and mud juice filter to deliver to vacuum suction filter (17) after being steam heated to 85-95 ℃ in (16).Filtrate (filtered juice) pump is clear juice case (11) extremely once.In floating device (10) the lower floor settled layer clear liquid account for the mixing juice total amount 80% in (10) large and small endless tube of device drain into once clear juice case (11) and filtered juice (account for mixing juice total amount 15%) in the lump pump to stove drying neutralizer (12) carry out stove drying.Intensity of sulfitation is 18-25ml, makes it reach 7.0-7.3 with the pH value of the clear juice that neutralizes.The defeco-sulfitated juice that comes out through (12) is sent into settling tank (14) again and is carried out precipitate and separate after second heater (13) is heated to 98-105 ℃, defeco-sulfitated juice enter (14) preceding by (8) add 1PPm(to sugarcane than) flocculation agent.Settling tank (14) bottom mud juice directly enters vacuum suction filter (17) and filters, and filtered juice is pumped to (11).The multilayer size endless tube discharge of settling tank supernatant liquid (the clear juice of secondary) in (14) sent into subsider juice case (15) and is pumped to next multiple-effect evaporation operation.

Embodiment:

Carried out the continuous 8 days industrial experimentation of this technology on the 2000 ton per day scale series of 1990/1991 press for extracting juice Ji Zaijing bank sugar refinery.Increased floating device in the peace and quiet workshop of this factory (sulfurous method), whisking machine, static mixer, phosphoric acid neutralizer, the tower that flocculates in advance, scum silica frost mud juice well heater etc.From the pre-grey PH7.0 of mixing juice elder generation that squeezing machine comes out, preprocessing industry phosphoric acid compares 150PPm to sugarcane continuously, being pumped to peace and quiet workshop once heats (50-60 ℃) And and adds milk of lime master ash to PH11, enter whisking machine, get blisters, mix through machinery, measure continuous processing industry phosphatase 11 50PPm/ to the sugarcane ratio with spinner-type flowmeter, after mixing, enter pre-flocculation tower, stop outflow in about 2 minutes, add flocculation agent (T type polyacrylamide) 3PPm/ again, after static mixer mixes, enter in the floating device the sugarcane ratio, stop about 40 minutes come-ups, settlement separate.Scum silica frost is scraped through scum silica frost by scraper plate and is sent to scum silica frost mud juice thermotank, and mud juice is subjected to static pressure to be heated to 85-95 ℃ ， And to the scum silica frost mud juice thermotank in the lump to filter toward vacuum suction filter from force feed.In the settling vessel effusive once clear juice and filtered juice all enter clearly the juice case in the lump pumping stove drying neutralizer carry out stove drying and neutralize.Intensity of sulfitation 20-22 milliliter, in and PH7.0-7.5, defeco-sulfitated juice directly is sent to settling tank again and carries out precipitate and separate after second-heating (98-105 ℃).Before settling tank, add flocculation agent 1PPm(to the juice ratio), average color value of clear juice is 2154ICUMSA after the settling tank secondary sedimentation, turbidity is 737, colloid clearance 53.8%, purity improves AP+3.64, GP+2.73.

It is tangible adopting " low temperature highly basic " to improve sulfurous method cleaning technique effect.This method is utilized the high-alkali best iso-electric point of PH11 under 55 ℃ of lesser tempss, remove non-sugared impurity, especially colloid in a large number, organism.Colloidal organic matter is removed more than 50% in the clear juice after the separation of drifting along, and turbidity reduces significantly.From original 2000-3000, to reduce to about 500-10000, colour also has greatly improved, the commerieal sugar quality of producing is significantly improved, and its physical and chemical index guarantees to reach the first sugar standard, near the top grade sugar level.The comparison of every technology quality index of technology of the present invention that following table is classified as and sulfurous method cleaning technique actual achievement:

Advantages such as it is obvious that the present invention has peace and quiet effect, easy and simple to handle, and it is few that low equipment investment, finings consumption increase expense, good in economic efficiency, thereby broad prospect for its application is arranged.

Claims (2)

1, a kind of improved sulfurous method sugaring cleaning technique comprises that mixing juice is through giving ash, once heating, stove drying neutralization (transferring about PH to 7), second-heating, precipitate and separate step, it is characterized in that once adding " low temperature highly basic " flow process promptly between heating and the stove drying neutralization, one time Heating temperature is 50-60 ℃, adding milk of lime afterwards makes the mixing juice pH value rise to 11 And adding phosphoric acid and flocculation agent, in floating device, fully react and separate with drifting along, obtain once clear juice and mud juice respectively, in stove drying, finish peace and quiet process then with grade.

2, according to the described cleaning technique of claim 1, it is characterized in that increasing an essential equipment-floating device, floating device and be the garden cylindricality open container that has at the bottom of the taper, be divided into three layers, upper strata and scraper plate arranged except that vessel space for the come-up layer, level control box, central downtake are formed, two-layer down is settled layer, a plurality of endless tubes are arranged in the settled layer, be used to drain juice clearly.

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