WO2007111523A1

WO2007111523A1 - Sugar production method

Info

Publication number: WO2007111523A1
Application number: PCT/RU2006/000138
Authority: WO
Inventors: Afanasy Moiseevich Kim; Sergey Sergeevich Karabuta
Original assignee: Afanasy Moiseevich Kim; Sergey Sergeevich Karabuta
Priority date: 2006-03-24
Filing date: 2006-03-24
Publication date: 2007-10-04
Also published as: CN101400807A

Abstract

The inventive method consists in forming nonsucrose precipitates during a sucrose extraction process in a diffuser by binding nitrogen-containing and nonnitrogenous high-molecular nonsucroses and colloidal dispersion agents, deposing nonsucrose precipitates on beet cossets and in removing them from a diffusion juice with a beet pulp, aggregating nonsucrose dispersed particles in the diffusion juice neutral-acid medium, flocculating said particles and removing them together with a precipitate by filtering or separating, defecating a filtrate, coagulating and flocculating a defecated juice nonsucroses in an alkaline medium, separating the precipitate, neutralising the purified juice, thickening it and in boiling a fillmass. The method uses in said production process the synergism of the interaction of inorganic coagulants of metal salts solutions and organic flocculants of synthetic polymers, thereby making it possible to substantially improve the purity of sugar-containing solutions and to reduce a production process at a lime/carbon dioxide purification plant.

Description

Method for the production of sugar

(i) Technical Field

The invention relates to the sugar industry.

(ii) Prior Art

A known method for the production of sugar, providing for the diffusion of juice by scalding beet chips and its extraction, preparing a solution of an inorganic coagulant of aluminum dihydroxosulfate and a non-anionic (cationic) flocculant polio-4-vinyl-N-benzyl, isothermally and redistribute it. to reduce the content of colloidal dispersion substances and sucrose loss in diffusion juice (SU 1377294 from 02.29.88).

The disadvantage of this method is the low cleaning effect of beet juice due to the use of inorganic coagulant and high molecular weight flocculant in the mixture at the beginning of the sucrose extraction process.

A known method for the production of sugar, comprising crushing sugar beets into chips, scalding it and feeding it to a diffusion apparatus for extraction, obtaining diffusion juice and purifying it simultaneously with extraction by using an aqueous solution containing a water-soluble polymer as an extractant, an electrolyte, a bleaching reagent, and an antiseptic with maintaining the pH of the diffusion medium using carbon dioxide and subsequent filtration, condensation of juice and boiling sugar (RU Ne2255980 C1, 07/10/2005). The method involves carrying out an extraction process while maintaining a pH of 8.5-8.8, a temperature of 72 ° C and an extraction time of 90 minutes.

The disadvantage of this method is that in the extraction process is not achieved a sufficiently high cleaning effect. During the extraction of sucrose from beet chips in diffusion juice, protein, pectin and reducing substances and other dissolved products of protopectin hydrolysis are accumulated, the isocatalytic points of which pH 5.5 - 7.5 do not coincide with the proposed maintenance of a pH level of 8.5 - 8.8 juice -chip mixture, and therefore their micellation and coagulation, the reagents and polymer flocculant proposed in the method can not always be deep. This is confirmed by the fact that under the mentioned conditions for purification of the extractable juice, organic synthetic polymer flocculants are not sufficiently effective when they are used for purification of ionic and nonionic non-sugars of diffusion juice in one stage.

(iii) Disclosure of the invention

The technical result of the invention is to increase the cleaning effect of beet juice at the extraction stage and at the stage of lime treatment, reducing lime consumption and sucrose loss in the filter cake.

The technical result is achieved by the proposed method, which includes obtaining beet chips, scalding it before feeding it into the diffusion apparatus or heating it in the latter, extracting sucrose from the chips with feed water, removing diffusion juice from the apparatus and unloading the pulp, introducing an aqueous solution, containing a non-anionic flocculant and an acidic reagent into the feed water supply zone of the diffusion apparatus body, as well as the introduction of an inorganic coagulant solution and a calcium hydroxide solution into the beet chip supply zone or into the middle zone of the apparatus body to purify the juice from high molecular weight compounds and colloidal dispersion substances simultaneously with extraction . An inorganic coagulant solution and an acidic reagent solution are introduced into the obtained diffusion juice to a pH of 4.5-5.5 to coagulate high molecular weight compounds and colloidal dispersed impurities in an acidic medium. Then, milk of lime is added to the diffusion juice until a pH of 6.5-8.5 is reached, a solution of a non-anionic flocculant is introduced, it is heated to 60-65 ⁰ C and a reagent is introduced to accelerate the process of flocculation of non-sugar particles, the precipitate formed is separated, and then the juice is defecated with lime milk to a pH of 10.8-11.4. An inorganic flocculant solution, a decolorizing reagent is added to the defecated juice, the pH is adjusted to 9.1-9.3 with an acidic reagent, heated to 70-75 ⁰ C, the pH is reduced to 7.8-8.2 and filtered. Refined juice is sent to thicken and boil massecuite. After heating to 70-75 ^° C, it is advisable to add a solution of a non-cationic flocculant to the defecated juice.

Among non-anionic flocculants, polycationites and polyampholytes can be used, in particular quaternary ammonium salts, polyepichlorohydrin dimethylamines, polydiallyldimethylammonium halides, cationic and nonionic polyacrylamides, organoelement polyflocculants, starch, starch / dextrin 10 mg, 10 mg yellow gel.

As an acidic reagent, orthophosphoric or polyphosphoric acid is used in an amount of 20-120 mg / l of juice.

Of the inorganic coagulants, titanium salts, as well as basic aluminum salts, activated by the multivalent anions of orthotitanic, polyphosphoric, silicic, or sulfuric acids, should be used, and aluminum oxalate, titanium, aluminum and iron sulfates, basic aluminum chloride in active form, and hydroxocomplexes and freshly precipitated hydroxides in an amount of 0.0001-0.008% by weight of beets.

Silicon-polymer compounds in an amount of 0.005-0.01% by weight of beets, active silicic acid - 0.0001-0.03% by weight of beets, modified aluminosilicate compounds in an amount of 0.001-0.009% can be used as a reagent that accelerates the process of flocculation of non-sugar particles. to the mass of beets.

Organic and inorganic peroxides and hydroperoxides, in particular, hydrogen peroxide in an amount of 10-90 mg / l, as well as ozone, sulfur dioxide, should be used as a bleaching reagent.

Among non-cationic flocculants, it is advisable to use polyanionites and polyampholytes, in particular, non-ionic and anionic polyacrylamides, sodium alginate, carboxymethyl cellulose, gelatin, casein, and also a mixture of aluminosilicate with organic modifiers in an amount of 10-100 mg / l.

The method is as follows.

Beet root crops are ground in beet slicers to produce beet chips. The latter is scalded before being fed to the column diffusion apparatus or it is heated directly in the screw diffusion apparatus. Chips are extracted with feed water, the diffusion juice is removed from the apparatus with a temperature of 40-45 ⁰ C and a pH of 5.6-6.5 and the pulp is unloaded from it.

An aqueous solution is prepared containing a non-anionic flocculant and an acidic reagent.

Of these flocculants, polycationites and polyampholytes can be used, in particular, quaternary ammonium salts, polyepichlorohydrin dimethylamines, polydiallyldimethylammonium halides, cationic and nonionic polyacrylamides, organoelement polyflocculants, starch, starch / dextrin 10 mg, gelatin. Of the acidic reagents, orthophosphoric or polyphosphoric acid is used in an amount of 20-120 mg / l of juice. This solution is introduced into the apparatus body into the feed water supply zone.

An inorganic coagulant solution and a calcium hydroxide solution are introduced into the beet chip supply zone or into the middle zone of the diffusion apparatus body. Of the inorganic coagulants, titanium and basic aluminum salts are used, activated with multivalent anions of orthotitanic, polyphosphoric, silicic, or sulfuric acids, and they use aluminum oxalate, titanium, aluminum and iron sulfates, basic aluminum chloride in the active form, their hydroxocomplexes and freshly precipitated hydroxides in an amount of 0.0001-0.008% by weight of beets.

In the diffusion apparatus during the extraction process, a slightly acidic medium of the juice-chip mixture with a pH of ~ 5.6-6.5 is formed. Substances of colloidal dispersion (VCD) are extracted from the chips into diffusion juice during the entire extraction period, and high molecular weight compounds (IUDs) of non-sugars go into diffusion juice in the middle and last zones of the apparatus. To suspend or limit the release of IUDs from beet chips to diffusion juice, the method involves the deposition and coagulation of IUDs inside plant cells of beet chips with an improvement in the elastic modulus of beet tissue. This is achieved by the fact that a solution of the indicated inorganic coagulant is introduced into the chip supply zone into the extractor, and a solution of a non-anionic flocculant is introduced into the feed zone into the feed water apparatus.

Separate input of the inorganic coagulant and flocculant into the diffusion apparatus provides for the preparation of the active forms of metal hydroxides in the saponified mixture and their subsequent flocculation.

Education in the diffusion juice active metal hydroxides takes place through the formation of aqua complexes, e.g., [AI (H ₂ O) b] ³⁺ or hydroxo, e.g., TiO ^{(OH) (2 "x) +,} (where x depends on chemical composition and condition of the solution). The formation of aquacomplexes and hydroxocomplexes of metal salts in a sugar-containing solution and their hydrolysis leads to a system of aqua ions and hydroxonium ions. H ⁺ hydroxonium protons are bound by calcium hydrogen carbonate or Ca or Na hydroxides and give the process of hydrolysis of metal salts and the formation of active aquahydroxocomplexes a stable character. At pH 5.5–6.5, the Al, Ti, Fe aquions and their one, two, or three substituted ions are cation exchangers and form dispersed and colloidal formations with negatively charged sugar, moreover, an active dispersed colloidal solution created directly in the juice-chip mixture aqua-hydroxocomplexes and hydroxides of metal salts has a positive potential. Nesugar of diffusion juice is a colloidal dispersed mass characterized by a negative potential. As a result of the interaction of two heteropolar systems, dispersed particles of non-sugars are coagulated and adsorbed onto sparingly soluble coagulant salts, which partially settle on the walls of beet chips, which strengthens the shell of the chips. As the chips move inside the apparatus and gradually soften them, the non-sugar particles coagulated on its surface are affected by a flocculant moving with feed water towards the chips. In the diffusion juice inside the apparatus, adsorption of negatively charged non-sugar colloids by polyions takes place, coagulated particles are aggregated into aggregates, and IUDs are precipitated and flocculated inside the cell, which prevents their transition to diffusion juice and increases the elasticity modulus of beet chips. Thus, a significant part of the non-sugar colloidal dispersion and IUD are removed from the apparatus along with the pulp. As a result, the diffusion juice taken from the extractor has a higher purity than that obtained by the known method, and the number of non-sugars in the pulp is increased by more than 0.8-0.9%. This high purification effect of beet juice is due to the effective interaction inorganic coagulant with a flocculant and the effect of their combined effect on nesugar during the extraction process.

A solution of one of the inorganic coagulants mentioned above and a solution of an acid reagent, also mentioned above, are added to the resulting diffusion juice to pH 4.5-5.5 to coagulate high molecular weight compounds and colloidal dispersed impurities in an acidic medium, then add to the diffusion juice milk of lime until a pH of 6.5-8.5 is reached, a solution of a non-anionic flocculant is introduced, heated to 60-65 ° C and a reagent is introduced that accelerates the process of flocculation of non-sugar particles and the precipitate formed is separated by filtration or settling.

Silicon-polymer compounds in an amount of 0.005-0.01% by weight of beets, active silicic acid - 0.0001-0.03% by weight of beets, modified aluminosilicate compounds in an amount of 0.001-0.009% by weight are used as a reagent accelerating the process of flocculation of non-sugar particles. beets.

When cleaning diffusion juice, the synergistic effect is used during the interaction of an inorganic coagulant and an organic flocculant and a reagent that accelerates the process of flocculation of non-sugar particles and their adsorption. The resulting diffusion juice is subjected to purification from non-sugars, taking into account the following ongoing processes.

The hydrolysis reaction of aqueous solutions of inorganic coagulant metal salts can proceed in an acidic environment of diffusion juice at a pH of 3.5-6.5 and its temperature of 40 ° - 50 ° C. This determines one of the conditions for the use of inorganic coagulant in the purification of diffusion juice. Another condition determining the use of an inorganic coagulant is the isoelectric region of activity of the hydroxides of its salts. For example, for aluminum hydroxide AI (OH) _{3, the} lowest solubility corresponds to a pH of 6.5-7.8. At pH <6.5, partially soluble oxisolates of the cationic type are formed; at pH> 7.8, soluble anionic aluminates are formed. Therefore, the conditions for the use of inorganic coagulant based on salts aluminum metals for the acidic environment of diffusion juice are: coagulation of non-sugars at a pH of 4.5-6.5 and a process temperature of 40 ° - 50 ⁰ C, the formation of a precipitate and its separation at pH 6.5-7.8. These conditions are provided for purification of diffusion juice from non-sugars using an inorganic coagulant based on aluminum salts.

Due to the fact that active metal hydroxide, such as, for example, Al (OH) 3 • pNGO gradually loses NgO and decomposes, it is necessary to flocculate freshly coagulated with the help of active hydroxide non-anionic flocculant, and to accelerate the process, use a flocculation catalyst.

After separation of the precipitate, the juice is defecated with milk of lime in an amount of 0.1-0.3% CaO at a temperature of 50-65 ⁰ C until a pH of 10.8-11.4 is reached, while part of the VCP and IUD coagulates under the influence of lime, but part non-sugars and reducing substances decompose and partially peptize into solution. Most of these non-sugars are coagulated by the introduction of an inorganic coagulant, which is an anion exchange resin, at a juice pH of 9.1-9.3.

Then, a bleaching reagent is added to the juice, using organic or inorganic peroxides and hydroperoxides, in particular, hydrogen peroxide in an amount of 10-90 mg / l, as well as ozone, sulfur dioxide. The juice is heated to 70-75 ^° C, the pH is reduced to 7.8-8.2 with an acidic reagent, filtered and the purified juice is sent to thicken and boil massecuite.

Example 1. In a twin-screw diffusion apparatus serves beet chips having a sugar content (Cx) of 15.5%, solids (CB) of 19.05%, the purity (C) of beet juice is 81, 38%, heated, a non-anionic solution is prepared flocculant - polyelectrolyte polyepichlorohydrin dimethylamine in the amount of 60 mg / l of juice and acid reagent - phosphoric acid in the amount of 40 mg / l of juice. This solution is introduced into the feed water zone with a pH of 7.8 and a temperature of 72 ⁰ C in the apparatus body. At the same time, a solution of inorganic coagulant - aluminum oxalate in the amount of 65 mg / l of juice and a solution of calcium hydroxide - 75 mg / l of juice (0.05% by weight of beets) are prepared and these solutions are fed into the supply and heating zone of beet chips. The diffusion juice obtained by chip extraction has a purity of 4-86.5%. The content of non-sugars in pulp is 0.85%, the effect of juice purification is -31, 8%. Then, a solution of an inorganic coagulant is introduced into the diffusion juice — a solution of titanium sulfate salt TiO (SO ₄ ) ^{2 "1"} in an amount of 10 mg / l of juice and a solution of an acidic reagent - phosphoric acid H ₃ PO ₄ until a pH of 4.5 is reached for coagulation of high molecular weight compounds and colloidal dispersion in an acidic environment.

75 mg / L CaO (0.05% by weight of beets) is introduced into the acidic environment of the juice until a pH of 7.5 is reached and a non-anionic flocculant solution is introduced, heated to 65 ⁰ C, and a colloidal silicon solution is introduced to accelerate the flocculation process acid in the amount of 5 mg / l of juice and direct the juice into the sump to separate the sediment of non-sugars. Sludge juice defecated with milk of lime to pH 11, 4. An inorganic coagulant solution is added to the defecated juice - a solution of titanium sulfate salt in an amount of 7 mg / l of juice, a decolorizing reagent - hydrogen peroxide in an amount of 50 mg / l of juice and phosphoric acid until a pH of 9.2 is formed, heated to 75 ⁰ C, reduced acidic reagent juice pH to 8.1 and filter the juice to separate the precipitate. As a result, the purity of Ch juice is 93.9%, sugar content (Cx) - 14.46%, solids (CB) - 15.4%. The overall effect of EO purification is 71.6%.

Example 2. Beet shavings with a sugar content (Cx) of 15.1%, solids (CB) of 18.4%, and a purity (H) of beet juice of 82.1% are fed to the scalder shaft of the diffusion column apparatus. Prepare an aqueous solution of non-anionic flocculant - polydiallyldimethylammonium chloride in an amount of 40 mg / l of juice and acid reagent - phosphoric acid in an amount of 30 mg / l of juice. This solution is introduced into the feed water zone with a pH of 7.8 and a temperature of 72 ° C in the apparatus body. At the same time, a solution of an inorganic coagulant — titanium sulfate salt TiO (SO-O ²⁺ in the amount of 10 mg / L juice and a calcium hydroxide solution — 75 mg / L juice — is prepared and these solutions are fed to the scalder together with beet chips.

Diffusion juice obtained as a result of chip extraction has a purity of Ch - 86.9%. The content of non-sugars in beet pulp is 0.9%, the effect of purifying beet juice is 30.86%. Then, a solution of inorganic coagulant in an amount of 10 mg / l of juice and a solution of an acidic reagent, orthophosphoric acid, are introduced into the obtained diffusion juice until pH 5.0 is reached for coagulation of high molecular weight compounds and colloidal dispersed impurities in an acidic medium.

Into the acidic environment of the juice, milk of lime is introduced in an amount of 75 mg / l (0.05% CaO by weight of beets) until a pH of 7.5 is reached and a solution of non-anionic flocculant in an amount of 40 mg / l of juice is introduced, heated to 65 ° C, a solution is introduced colloidal silicic acid in an amount of 5 mg / l of juice and direct the juice into the sump to separate the sediment of non-sugars. Sludge juice defecated with milk of lime to pH 11, 4. A solution of inorganic coagulant in an amount of 7 mg / l juice is added to the defecated juice, a bleaching reagent is hydrogen peroxide in an amount of 30 mg / l juice and phosphoric acid until a pH of 9.2 is formed, heated to 75 ° C, and the pH of the juice is reduced with an acidic reagent to 8 , 1 and filter the juice to separate the precipitate. As a result, the purity of Ch juice is 94.3%, the sugar content (Cx) is 14.1%, and the solids content (CB) is 15.0%. The overall effect of EO cleaning is 72.7%.

Example 3. In a twin-screw diffusion apparatus serves beet chips, having a sugar content (Cx) of 15.5%, solids (CB) of 18.9%, and the purity (H) of beet juice is 82.0%. An aqueous solution of a non-anionic flocculant — polydiallyldimethylammonium chloride — is prepared in an amount of 40 mg / l of juice and an acid reagent — phosphoric acid in an amount of 30 mg / l of juice. This solution is introduced into the feed zone. water with a pH of 7.8 and a temperature of 72 ° C in the device.

At the same time, a solution of an inorganic coagulant — titanium sulfate salt ТУ (SO ₄ ) ²⁺ in the amount of 10 mg / l of juice and a calcium hydroxide solution - 75 mg / l of juice — is prepared and these solutions are fed into the middle zone of the apparatus, namely, in the third section, into the juice chip mixture.

Diffusion juice obtained as a result of chip extraction has a purity of Ch - 88.7%, sugar content (Cx) - 14.6%, solids (CB) - 16.5%. The content of non-sugars in beet pulp is 1.05%, the effect of purifying beet juice is 41.8%. Then, a solution of inorganic coagulant in the amount of 10 mg / l of juice and a solution of an acid reagent, orthophosphoric acid, are introduced into the diffusion juice to achieve pH 5.0 for coagulation of high molecular weight compounds and colloidal dispersed impurities in an acidic medium.

75 mg / L of lime (0.05% CaO by weight of beets) is introduced into the acidic environment of the juice until a pH of 7.5 is reached and a solution of non-anionic flocculant is added in the amount of 40 mg / L of juice, heated to 65 ° C, a solution is introduced colloidal silicic acid in an amount of 5 mg / l of juice and direct the juice into the sump to separate the sediment of non-sugars. Sludge juice defecated with milk of lime to pH 11, 4. A solution of inorganic coagulant in an amount of 7 mg / l of juice is added to the defecated juice, a bleaching reagent is hydrogen peroxide in an amount of 30 mg / l of juice and phosphoric acid until pH 9.2 is formed, and a non-cationic flocculant anionic polyacrylamide (Magofolos LT 27) is introduced in an amount 20 mg / l of juice, heated to 75 ^° C, reduced the pH of the juice with an acidic reagent to 8.1 and filtered the juice to separate the precipitate. As a result, the purity of Ch juice is 96.7%, sugar content (Cx) - 14.5%, solids (CB) - 15.0%. The overall effect of EO purification is 84.4%.

Claims

Claim

1. A method for the production of sugar, which involves obtaining beet chips, scalding it before feeding it into the diffusion apparatus or heating it in the latter, extracting sucrose from the chips with feed water, removing diffusion juice from the apparatus and unloading the pulp, introducing an aqueous solution containing a non-anionic flocculant and an acidic reagent in the feed water supply zone into the diffusion apparatus body, as well as the introduction of an inorganic coagulant solution and calcium hydroxide solution into the beet chip supply zone or into the middle the ith zone of the apparatus for purifying beet juice from high molecular weight compounds and colloidal dispersion substances simultaneously with extraction; in this case, an inorganic coagulant solution and an acidic reagent solution are added to the resulting diffusion juice to a pH of 4.5-5.5 to coagulate high molecular weight compounds and colloid -dispersed impurities in an acidic medium, then milk of lime is added to the diffusion juice until a pH of 6.5-8.5 is reached, a solution of a non-anionic flocculant is introduced, it is heated to 60-65 ⁰ C and a reagent accelerating the process of flocculation of non-sugar particles, the precipitate formed is separated, after which the juice is defecated with milk of lime to pH 10.8-11, 4, an inorganic coagulant solution and a bleaching reagent are added to the defecated juice, the pH is adjusted to 9.1-9.3 with an acidic reagent, heated to 70-75 ⁰ C, lowered the pH to 7.8-8.2, filtered, and the purified juice is sent to thicken and boil massecuite.

2. The method according to claim 1, characterized in that before or after heating the juice to 70-75 ⁰ C, a solution of a non-cationic flocculant is added to the juice.

3. The method according to claim 1, characterized in that among the non-anionic flocculants polycationites and polyampholytes are used, in particular quaternary ammonium salts, polyepichlorohydrin dimethylamines, polydiallyldimethylammonium halides, cationic and nonionic polyacrylamides, organoelement polyflocculants, starch, dextrin, gelatin in an amount of 10-110 mg / l of diffusion juice.

4. The method according to claim 1, characterized in that, as an acidic reagent, orthophosphoric or polyphosphoric acid is used in an amount of 20-120 mg / l of juice.

5. The method according to claim 1, characterized in that the inorganic coagulants use titanium as well as basic aluminum salts activated by multivalent anions of orthotitanic, polyphosphoric, silicic, or sulfuric acids, and use aluminum oxalate, titanium, aluminum and iron sulfates, the main aluminum chloride in active form, their hydroxocomplexes and freshly precipitated hydroxides in an amount of 0.0001-0.008% by weight of beets.

6. The method according to claim 1, characterized in that as a reagent that accelerates the process of flocculation of non-sugar particles, silicon-polymer compounds are used in an amount of 0.005-0.01% by weight of beets, active silicic acid is 0.0001-0.03% by the mass of beets, modified aluminosilicate compounds in an amount of 0.001-0.009% by weight of beets.

7. The method according to claim 1, characterized in that, as a bleaching reagent, organic or inorganic peroxides and hydroperoxides are used, in particular hydrogen peroxide in an amount of 10-90 mg / l, as well as ozone, sulfur dioxide.

8. The method according to claim 1, characterized in that of non-cationic flocculants use polyanionites and polyampholytes, in particular non-ionic and anionic polyacrylamides, sodium alginate, carboxymethyl cellulose, gelatin, casein, as well as a mixture of aluminosilicate with organic modifiers in an amount of 10-100 mg / l of juice.