CN1912143A

CN1912143A - Clear-muddy separation settling technology of sugar production

Info

Publication number: CN1912143A
Application number: CNA200510092554XA
Authority: CN
Inventors: 周少基
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-08-14
Filing date: 2005-08-14
Publication date: 2007-02-14

Abstract

The invention relates to cane juice purifying separating technology of sugar making. It includes the following steps: separating the initial extraction liquid and the secondary at sugar cane juicing stage; adding lime cream or other basic compound into the secondary extraction liquid or their mixture to make the pH value equal to 8.0-13; once or many times clarifying of chemical coagulation, flocculation, and solid-liquid separation; mixing the clarified liquid with the initial extraction liquid to do further clarifying by limebase process, phosphoric acid and sulphitation process.

Description

Clear-muddy separation settling technology of sugar production

Technical field

Patent of the present invention belongs to a kind of peace and quiet purification separation process technique of sugarcane juice of Closed Circulation in Sugar Production.

Background technology

The cane sugar manufacture production process comprises processes such as extraction of the juice, peace and quiet, crystallization, purging and drying.The peace and quiet process of sugarcane juice is a kind of physical chemistry purification technique of solution, at present main method be in sugarcane juice, add chemical coagulation and precipitation agent and flocculation agent to non-sugar component take off surely, absorption and granulation precipitate, separate by unit operations such as heating, sedimentation and filtrations.The main clarification technique method of present industrial application has lime method, sulfurous method and carbonatation process.Its main process is:

1. lime method: sugarcane draws the mixing sugarcane juice through squeezing process, adds milk of lime to acidity-basicity ph value and approximate about 8 in mixing juice, is heated to 100 ℃, adds that flocculation agent flocculates, sedimentation and filtering separation obtain juice clearly.

2. sulfurous method (is example with the phosphoric acid sulfurous method): sugarcane draws mixing juice through squeezing process, add phosphoric acid to phosphoric acid value and be about 350ppm, add milk of lime to pH value and approximate 7, carry out the heating first time, make the sugarcane juice temperature rise to 55～65 ℃, (intensity of sulfitation 10～25ml) keeps the pH value to equal 7, carries out neutralization reaction to add sulfurous gas and milk of lime.Defeco-sulfitated juice after the neutralization reaction carries out the heating second time, makes temperature rise to 100～102 ℃, carries out sedimentation and filtering separation and draws final clear juice.

3. carbonatation process: sugarcane draws the mixing sugarcane juice through squeezing process, add milk of lime to pH value and approximate 7, be heated to 55～65 ℃, adding carbonic acid gas and milk of lime to lime carbonate growing amount is 2% of sugarcane juice, make the pH value remain on 10～11, carry out the full charge reaction first time, filter then, it is 8.2～8.4 that the gained filtered juice adds carbonic acid gas to pH value, be heated to 75～85 ℃, filtration obtains two clear juice, and two clear juice feed sulfurous gas to pH value and equal about 7, promptly obtains final clear juice.

In above these methods, the lime method production cost is minimum, but can only produce raw sugar, sulfurous method and carbonatation process are used to produce plantation white sugar, wherein the white sugar content of sulfur dioxide of sulfurous method production is higher, and the white sugar quality that the production white sugar quality of carbonatation process is produced than sulfurous method is good, but cost is higher, and produce a large amount of calcium carbonate alkaline filter muds, environment is polluted.

Summary of the invention

The purpose of patent of the present invention is the deficiency that overcomes in the existing Technology, and for sugar-refining industry provides a kind of production cost lower, sugar yield is higher, and can produce the cane juice clarification Technology of no sulphur or doctor negative plantation white sugar or edible raw sugar.

In sugarcane extraction of the juice process, sugarcane at first is broken, and carries out repeatedly squeeze juice extracting through a too much seat squeezing machine then.First sugarcane juice (calling first expressed juice in the following text) that squeezing machine is squeezed out and accounted for the sucrose amount about 70%, in order to extract sucrose part to greatest extent, all be added with infiltration water in the repeatedly expressing process afterwards, amount of seepage is about 16～20% of sugarcane, 40～50 ℃ of water temperatures, one of the most frequently used penetration mode is compound infiltration, and these infiltration squeezing sugarcane juices are generally from second squeezing machine come out (call two in the following text and press juice).Existing Closed Circulation in Sugar Production technology is that two press juice to mix with the first expressed juice that comes out from first squeezing machine, are called mixing juice, promptly carry out clarifying treatment after mixing juice Via sieve filters.

First expressed juice and two presses the essential characteristic of juice to be, the purity height of first expressed juice, and non-sugar content, especially polyose, Polyphenols, unmanageable foreign matter content such as gummy class is little.Two press juice owing to added the hot water that certain temperature is arranged, and the non-sugar stripping is many, and purity is low, and the hammer degree is also low.

The sugar clarification principle is told people, sugarcane juice has two coacervation points, the non-sugar of wherein high pH value coacervation point (pH value=10～11) cohesion is maximum, thereby the quality product of carbonatation process sugaring is higher, must consume a large amount of chemical clarification agent but under high pH value, all handle sugarcane juice, cause the production cost height.

Handle two with high pH value coacervation point and press juice, because its amount is few relatively, it is few to consume lime, again with the first expressed juice neutralization, because sugarcane juice itself, especially first expressed juice are good acidic mediums, will greatly reduce production costs after the clarification.

Polysaccharide in sugarcane juice such as starch, pectin, impurity such as dextran and sucrose will be difficult to be removed when existing simultaneously, and be the stable important factors of other non-sugar, because two press the hammer degree of juice low, sugar part is low, therefore it is clarified, the non-sugar clearance is high relatively, and experiment shows, use the same method, two press clarification of juice efficiency ratio mixing juice height.And the processing of first expressed juice is relatively easy, and during with phosphoric acid and lime treatment first expressed juice, the calcium salt content of clear juice has only 0.01%, illustrates that the clarifying major impurity composition of influence is at two pressure juice.And make CaSO just because of these compositions ₃, wait calcium precipitation incomplete, cause subsider juice purity to improve little and sulphur content high.

The purpose of patent of the present invention is to realize by such mode, and in the sugarcane extraction of the juice stage, the sugarcane juice of first squeezing machine, i.e. first expressed juice and by adding the sugarcane juice that comes out from second squeezing machine that squeezes behind the infiltration water, promptly two presses juice separately.Milk of lime or other basic cpd are added the two turbid juice of pressing juice or two pressure juice and part first expressed juice composition to pH value=8.0～13, carry out the one or many clarification of chemical coagulation, flocculation and solid-liquid separation.The gained subsider juice mixes with first expressed juice again, and mixing juice adopts lime method, and existing technologies such as sulfurous method or phosphoric acid method are further clarified.

Embodiment

Embodiment 1: the thick juice of two pressures that comes out from second squeezing machine obtains two pressure juice after filtration, two press juice to mix with 10～20% first expressed juice, add milk of lime to pH value=7.8～8.2, be heated to 65～75 ℃, add 300～400ppm phosphoric acid, add milk of lime to pH value and be about 10～11, carry out 1500～2000 rev/mins of stirring reactions and inflated 1 minute, the poly-propionic acid amide flocculation agent that adds 10～12ppm, stirring reaction 1 minute floats in Air-float separator then, and clear juice and come-up mud juice obtain floating, mud juice filters, and the gained filtered juice obtains two with the clear juice merging of come-up and presses clear juice.Two press clear juice and come out from first squeezing machine, filtered first expressed juice mixes, obtain mixing juice, be heated to 100 ℃, add the polyacrylamide flocculant of 1～2ppm, carried out stirring reaction 3 minutes, enter settling vessel and carry out sedimentation, clear juice of the sedimentation that obtains and precipitation mud juice, mud juice gets filtered juice after filtration, and the clear juice of filtered juice and sedimentation is mixed into final clear juice.

Embodiment 2: the thick juice of two pressures that comes out from second squeezing machine obtains two pressure juice after filtration, add milk of lime to pH value=6.8～7.2, be heated to 55～60 ℃, add milk of lime to pH value and be about 11.5～12,0.1% the sal epsom (being made into the solution of 0.5% concentration) that adds the sugarcane juice amount, carried out stirring reaction 3 minutes, add the poly-propionic acid amide flocculation agent of 1～2ppm, stirring reaction 3 minutes, in settling vessel, carry out sedimentation then and obtain clear juice of sedimentation and precipitation mud juice, mud juice filters, and the clear juice merging of gained filtered juice and sedimentation obtains two and presses clear juice.Two press clear juice to merge with the first expressed juice that comes out from first squeezing machine obtains mixing juice, in mixing juice, add phosphoric acid to sugarcane juice phosphoric acid amount 300ppm, add milk of lime to sugarcane juice pH value=6.8～7.2, be heated to 55～65 ℃, add sulfurous gas and milk of lime (intensity of sulfitation 6～8ml), keep the pH value to equal 7, carry out neutralization reaction.Defeco-sulfitated juice after the neutralization reaction is heated to 100～102 ℃, add the poly-propionic acid amide flocculation agent of 1～2ppm, stirring reaction 3 minutes carries out sedimentation then and obtains clear juice of sedimentation and precipitation mud juice in settling vessel, mud juice gets filtered juice after filtration, and the clear juice of filtered juice and sedimentation is mixed into final clear juice.

Embodiment 3: two presses juice to mix with 30% first expressed juice, add milk of lime to pH value and approximate 7, be heated to 55～60 ℃, adding carbonic acid gas and milk of lime to lime carbonate growing amount is 2% of sugarcane juice, keep the pH value to equal 10～11, carried out stirring reaction 3 minutes, filter then, it is 9 that the gained filtered juice feeds carbonic acid gas to pH value, add the 5ppm polymerize aluminum chloride, stirring reaction 3 minutes adds polyacrylamide flocculant (1～2ppm), stirring reaction 3 minutes, carry out sedimentation then in settling vessel, obtain clear juice of sedimentation and precipitation mud juice, mud juice filters, the clear juice merging of gained filtered juice and sedimentation obtains two and presses clear juice, two press clear juice and first expressed juice to be mixed into mixing juice, add phosphoric acid to pH value and equal 7, are heated to 100 ℃, add polyacrylamide flocculant (1～2ppm), stirring reaction 3 minutes carries out sedimentation then in settling vessel, obtain clear juice of sedimentation and precipitation mud juice, the gained mud juice filters, and the clear juice of gained filtered juice and sedimentation is merged into final clear juice.

Claims

1. the syrup separation of cloudy and clear clarification process of a Closed Circulation in Sugar Production, it is characterized in that, to adopting squeezing and adding the Closed Circulation in Sugar Production method that water permeates the multiple extraction sugar material syrup that combines, to directly squeeze containing the higher first pressing syrup of sucrose purity and separating of extraction in the extraction of the juice stage by adding the low-purity syrup of extracting entry or dilute juice infiltration back to the sugar material, this low-purity syrup directly or with part first pressing syrup is mixed as turbid juice, carry out the alkalescence clarification, promptly transfer to pH value=8～13 with calcium oxide or magnesium oxide or water glass or alkaline matters such as their miscellany or hydrate, be heated to 40～105 ℃, directly carry out solid-liquid separation or add chemical coagulation, carry out the one or many clarification of solid-liquid separation behind the flocculation agent.The subsider juice of gained mixes with above-mentioned untreated first pressing syrup, clarifies again.

2. the syrup separation of cloudy and clear clarification process of a kind of Closed Circulation in Sugar Production according to claim 1 is characterized in that, described low-purity syrup is mixed the turbid juice of forming with part first pressing syrup, and the combined amount of its first pressing syrup is 0～50% of a first pressing syrup total amount,

3. according to the syrup separation of cloudy and clear clarification process of claim 1 and 2 described a kind of Closed Circulation in Sugar Production, it is characterized in that, turbid juice transfers to pH value=8～13 with alkaline matter and clarifies, and the chemical coagulation, the flocculation agent that are adopted comprise: the organic polymer coargulators such as polyacrylamide of (1) molecular weight more than 1,000,000; (2) precipitation agent of calcium such as organic or inorganic acid such as carbonic acid gas, sulfurous gas, phosphoric acid or phosphoric acid salt or their polymkeric substance, oxalic acid or oxalate, phytic acid or phytate, tannin and its esters; (3) mineral acid aluminium salt, zinc salt, magnesium salts etc. produce the coagulating sedimentation agent of precipitin reaction in syrup.

4. the syrup separation of cloudy and clear clarification process of a kind of Closed Circulation in Sugar Production according to claim 1 is characterized in that, turbid juice transfers to pH value=8～13 with alkaline matter and clarifies, and the solid-liquid separating method that is adopted comprises: (1) settling process; (2) air supporting method; (3) filtration method.