SU1604855A1 - Method of producing last-crystallization massequite - Google Patents

Abstract

The invention relates to the sugar industry, in particular to obtaining a jumbo bee of the last crystallization. The purpose of the invention is to reduce the sugar content in molasses and accelerate the crystallization of massecuite. In the vacuum apparatus create a vacuum in the range of 0.060-0.067 MPa. The swelling is recruited, the apparatus is filled with it until the heating surface of the steam chamber is completely closed, steam is fed into the heating chamber, the sugar crystallization centers are condensed and refined. The buildup of sugar crystals is carried out at a supersaturation ratio of 1.15-1.25 by continuous or frequent priming of the intended for this mother liquor heated to 5-10 ° C above the massecuite temperature in the apparatus. The temperature of boiling during the period of growth of sugar crystals is maintained at 68-70 ° C. The final thickening of the massecuite is carried out at 65-68 ° C, depending on the dB massecuite. Before lowering the massecuite into the receiving grinder of the crystallization unit, it is swayed with hot water heated to 70 ° C to 91.0-91.8% CB, while ensuring the oversaturation of its inter-crystal solution is 1.22-1.25. The crystallization of the massecuite is carried out when it is cooled in the mash-crystallizers, connected in series to the crystallization unit. From the receiving agitator, the massecuite is first fed to the first crystallization stage to the first mash mixer, where the mash of the inter-crystal solution of massecuite is kept in the range of 1.22-1.25. At the second stage of crystallization, the supersaturation coefficient of the inter-crystal massecuite solution is maintained within 1.15-1.18 by controlling the water temperature in the cooling system of the second mash. At each subsequent crystallization stage, after the second mash mixer, the supersaturation coefficient of the inter crystal solution is maintained by 0.02-0.03 less than the previous one, which is also achieved by controlling the water temperature in the mash cooling systems according to the laboratory masonry analyzes. The need for such a decrease in the supersaturation of the crystallization stages is due to the creation of optimal conditions for the deep depletion of the mash-solution of the massecuite as its temperature decreases and the viscosity increases. At the final stage of crystallization, the supersaturation coefficient of the inter-crystal solution is maintained at 1.02-1.03. 1 tab.

Description

one

(21) 4655912 / 31-13

(22) 02.28.89

(46) 07.11.90. Bul № 41 (71) Moscow Technological Institute of Food Industry (72) A.A. Slavnsky, V. I. Tuzhilkin, A. R. Sapronov and A. 3. Moren

(53) 664.1.054 (088.8)

(56) Cat Yu.D. About the operation of the crystallization plant. - Sugar industry, 1952, No. 3, p. 41

Instructions for the behavior of the process of sugar beet production. -M., VNRSHSP, .1985, pp. 239-252.

(54) METHOD FOR OBTAINING A UTFELL FOR LAST CRYSTALLIZATION;

(57) The invention relates to the sugar industry, in particular to obtaining the massecuite of the last crystallization. The purpose of the invention is to reduce the sugar content in molasses and accelerate the crystallization of massecuite. In the vacuum apparatus create a vacuum in the range of 0.060 - 0.067 MPa. The swelling is recruited, the apparatus is filled with it until the heating surface of the steam chamber is completely closed, & steam is supplied to the heating chamber, the sugar crystallization centers are condensed and refined. The growth of sugar crystals is carried out at a supersaturation coefficient of 1.15-1.25 by continuous or frequent priming of the intended for this wipe, heated by 5-10 ° C above the massecuite temperature in the apparatus. The temperature of boiling during the period of growth of sugar crystals is maintained at 68-70 ° C. The final thickening of the massecuite is carried out at 65 68 C, depending on the dB massecuite. Before descending of the masonry to the receiving bakery mixer of the crystallization unit, it is swayed with hot water heated to 70 ° C to 91.0-91.8% CB, while ensuring the oversaturation ratio of its inter-crystal solution is 1.22-1.25. The crystallization of the massecuite is carried out when it is cooled in crystallizer agitators, connected in series to the crystallization unit. From the receiving agitator, the massecuite is first fed to the first crystallization stage to the first mash mixer, where the mash of the inter-crystal solution of massecuite is kept in the range of 1.22-1.25. At the second stage of crystallization, the supersaturation coefficient of the mash-solution of massecuite is maintained within 1.15 - 1.18 by adjusting the water temperature in the cooling system of the second mash. At each subsequent crystallization stage, after the second mash mixer, the supersaturation coefficient of the inter crystal solution is kept by 0.02-0.03 less than the previous one, which is also achieved by controlling the water temperature in the mash-cooling cooling systems according to the massecuite laboratory analyzes. The need for such a reduction in the rate of crystallization is caused by the creation of optimal conditions for the deep depletion of the mash-solution of the massecuite as its temperature decreases and the viscosity increases. At the final stage of crystallization, the supersaturation coefficient of the inter-crystal solution is maintained at 1.02-1.03. 1 tab.

S

(L

R

The invention relates to the sugar industry, in particular to obtaining a massecuite of the last crystallization.

The purpose of the invention is to reduce the sugar content in molasses and accelerate the prophylaxis of massecuite crystallization.

The method is carried out as follows.

A vacuum in the range of 0.060-0.067 MPa is created in the vacuum apparatus. The swelling is recruited, the apparatus is filled with it until the heating surface of the steam chamber is completely closed, steam is fed into the heating chamber, the sugar crystallization centers are condensed and refined. The buildup of sugar crystals is carried out at a crosshair ratio of 1.15-1.25 by continuous or frequent priming of the intended for this machine, heated 5-10 ° C above the temperature of the massecuite in the apparatus. The temperature of boiling in the period of growing sugar crystals is maintained at 68-70 C. The final concentration of the massecuite is carried out at 65-68 С, depending on the dB massecuite. Before lowering the massecuite into the receiving floatation chamber of the crystallization unit, it is swayed with hot water heated to 70 ° C to 91.0-91.8% CB, while ensuring the oversaturation of its inter-crystal solution is 1.22-1.25.

The swinging of the filling liquid of the last criticalization with hot water before descending from the vacuum apparatus to 91.0-91.8% GB is necessary to maintain the optimum conditions for its crystallization by cooling in a crystallization unit. If the massecuite is swayed before descending from the vacuum apparatus to a dry matter content of less than 91%. In this case, it is difficult to ensure the necessary regime of depletion of the massecuite by the crystallization stages in the mill pelletizers of the crystallization unit. In practice, this leads to an increase in the duration of crystallization and a decrease in the sugar yield. In the event that the massecuite is drained from the vacuum of the apparatus with a dry matter content of more than 91.8%, difficulties arise in maintaining the necessary transition differential; On

the destruction of the de-icing solution of the filament solution of the fillet can lead to additional water buildup of the jumble for the fillet;

j

15; about 25 30

Q:

35

50

55

adversely affect the duration of crystallization and the loss of sugar in molasses.

The crystallization of the massecuite is carried out when it is cooled in mash-molds, connected in series to the crystallization unit. From the receiving agitator, the massecuite is first fed to the first crystallization stage to the first mash mixer, where the supersaturation ratio of the inter-crystal solution of massecuite is kept within 1.22-1.25.

Such requirements for microcrystalline solution are determined by the optimal conditions of its depletion during the movement of the massecuite crystallization stages from the first to the last mixer of a crystallization plant. Under these conditions, a minimum crystallization time is provided by cooling. If the inter-crystal solution of the massecuite in the first agitator is less than 1.22, then the crystallization time increases and the technological mode of exhaustion of the inter-crystal massecuite solution in subsequent masonry mixers is violated, which does not allow to reduce the purity of the molasses. When oversaturation is more than 1.25, flour may fall out, which decreases the mobility of the massecuite, requires additional water buildup of the massecuite and leads to an increase in the sugar content of molasses and the duration of crystallization of massecuite.

At the second stage of crystallization, the coefficient of dispersion of the inter-crystal massecuite solution is kept within 1.15-1.18 by controlling the water temperature in the cooling system of the second mash, i.e. in the first two baffle mixers, conditions are created for the maximum crystallization rate, by adjusting the transition cross-over between 0.07-0.09. Maintaining this difference is necessary to ensure an optimal growth rate of the crystals and a deep depletion of the inter-crystal solution of the massecuite in the first two stages of crystallization.

If the saturation coefficient at the second crystallization stage is kept below 1.15, the supersaturation difference increases, and in order to evenly deplete the mash solution of massecuite at subsequent crystallization stages, its water buildup may be required. When the coefficient of pereschis more than 1.18, the duration of crystallization and the sugar content in the mass, increases.

At each subsequent crystallization stage, after the second mash-mixer, the supersaturation coefficient of the inter-crystal solution is maintained by 0.02-0.03 less than the previous one, which is also achieved by controlling the water temperature in the cooling mixers systems according to laboratory data

in molasses, which negatively affects the achievement of the goal.

Before centrifuging, the massecuite is heated and centrifuged to obtain sugar and molasses.

Example 1. In a vacuum apparatus, a vacuum of 0.060 MPa is created, the first effluent of the massecuite 1 from DB is 78.5% 10 83.2% until the heating surface of the steam chamber is completely closed, steam is turned on in the heating chamber of the reactor; crystallization centers, the introduction of ca- 15 powder in the amount of 60-80 g at

thorns analyzes of baffles. Necessity 76 ° С. Cree Growth ;; ;; ;;; o; o ;; ;

Such a decrease in the supersaturation over a set of crystallization pensions is due to the creation of optimal conditions for the deep depletion of the mash-solution of the massecuite as its temperature decreases and the viscosity increases. If the reduction in supersaturation is maintained at less than 0.02, the crystallization process is prolonged and the sugar content in molasses is not reduced. When the supersaturation difference in the subsequent crystallization steps exceeds 0.03, the optimum conditions for exhausting the mash-solution of massecuite are not maintained, and it may be necessary to carry out massecuite masses on these masonry mixers. All this does not allow to reduce the sugar content in molasses and to accelerate the crystallization of massecuite when it is cooled.

20

at an inter-crystalline solution supersaturation coefficient of 1.15 by continuously or frequently pumping up the first mother liquor 1 heated to a higher massecuite temperature in the apparatus. During the period of growth of crystals, the temperature of the baffle is about 68 ° C. At the end of the boiling down, with the final 25 thickening of the massecuite, the refining swelling with DB 72 5% is accumulated in the apparatus while the DB mason is kept within about 78%. The last stage of boiling is carried out at 65 ° C to 95.5% CB, Q and then, before descending from the apparatus, UFEL is swayed with hot water with a temperature of 70 ° C to 91% CB and lowered into the receiving mash mixer of the crystallization plant. It includes eight series-connected mold-crystallisers (crystallization stages) with a tubular heat exchange surface and individual water-cooling systems. From the receiving mash of the agitators, the massecuite is supplied to the first mash from the first crystallization stage. At the first crystallization stage, the floatation temperature is 68 ° C, and the supersaturation coefficient of its inter-crystal solution is kept at 1.22, and at the second stage the nepecbmie coefficient is reduced to 1.15. At the same time, between the first and second stages of crystallization, a drop difference of 50 equal to 0.07 is created. At each subsequent stage of crystallization, the supersaturation coefficient is kept by 0.02 less than at the previous one, which is achieved by regulating the water temperature in the cooling systems of the mash-up mixers, orienting to the data of laboratory analyzes of the massecuite. Crystallization of the massecuite is completed at the last stage of crystallization at 40 ° C, and the coefficient

When the massecuite reaches the last stage of crystallization in the masonry mixer, the supersaturation ratio of the masonry massecuite solution is 1.02-1.03. This is necessary to complete the crystallization process and prepare the mash for centrifugation. Fulfillment of these conditions ensures good separation of sugar and molasses in the field of centrifugal forces. You get sugar last crystallization with a minimum content on the surface of molasses in the form of a film. When supersaturation is lower than 1.02, part of sugar crystals may dissolve when preparing mash for centrifugation, and when the value of supersaturation is higher than 1.03, mash is centrifuged, sugar content increases in molasses in centrifugal sugar and may be lost in the form of flour.

6048556

in molasses, which negatively affects the achievement of the goal.

Before centrifuging, the massecuite is heated and centrifuged to obtain sugar and molasses.

Example 1. In a vacuum apparatus, a vacuum of 0.060 MPa is created, the first effluent of the massecuite 1 from DB is 78.5% 10 83.2% until the heating surface of the steam chamber is completely closed, steam is turned on in the heating chamber of the reactor; crystallization centers, the introduction of ca- 15 powder in the amount of 60-80 g at

 76 ° C. Cree Growth ;; ;; ;;; o; o ;; ;

 76 ° C. Cree Growth ;; ;; ;;; o; o ;; ;

20

at an inter-crystalline solution supersaturation coefficient of 1.15 by continuously or frequently pumping up the first mother liquor 1 heated to a higher massecuite temperature in the apparatus. During the period of growth of crystals, the temperature of the baffle is about 68 ° C. At the end of the boiling down, with the final 25 thickening of the massecuite, the refining swelling with DB 72 5% is accumulated in the apparatus while the DB mason is kept within about 78%. The last stage of boiling is carried out at 65 ° C to 95.5% CB, Q and then, before descending from the apparatus, UFEL is swayed with hot water with a temperature of 70 ° C to 91% CB and lowered into the receiving mash mixer of the crystallization plant. It includes eight series-connected mold-crystallisers (crystallization stages) with a tubular heat exchange surface and individual water-cooling systems. From the receiving mash of the agitators, the massecuite is supplied to the first mash from the first crystallization stage. At the first crystallization stage, the floatation temperature is 68 ° C, and the supersaturation coefficient of its inter-crystal solution is kept at 1.22, and at the second stage the nepecbmie coefficient is reduced to 1.15. At the same time, between the first and second stages of crystallization, a drop of 0 0 equal to 0.07 is created. At each subsequent stage of crystallization, the supersaturation coefficient is kept by 0.02 less than at the previous one, which is achieved by regulating the water temperature in the cooling systems of the mash-mixers, orienting to the data of laboratory analyzes of the massecuite. Crystallization of the massecuite is completed at the last stage of crystallization at 40 ° C, and the coefficient

R

the supersaturation of the inter-crystal solution of the fillets was maintained at 1.02. Pe By centrifuging, the temperature of the massecuite is increased by 5 ° С due to the increase in the temperature of the water in the cooling system of the last mash mixer.

The mash obtained by the proposed method has a DB of 77.9%, the duration of crystallization by cooling Q is 27.5 hours, and before centrifuging, the massecuite contains 41.3% of crystals with an average size of 0.25 mm of chromaticity 37 conv. units, and molasses

Had db 60.1%. .t5

Simultaneously, boiling and filling of the massecuite is carried out by cooling the prototype. At the same time, prior to the operation of swinging the mash with hot water before descending from the apparatus, condition the boiling down with; according to the example of the proposed method, and at the end of boiling down it has 95.5% DM. Swinging the massecuite is directed to the normal dB of molasses, equal to 58.9% for 25 given conditions, the crystal content achievable in the massecuite and crystallization is complete at 40 ° C. Therefore, the prototype mash is shaken to 91.5 2% SAT and POS. 30 give from the receiving mixer to the first STZ a crystallization stump in the primary mixer with a temperature of 68 C. Passing through all the stages of crystallization, the massecuite is cooled to 40 ° C, and before 5 samples for centrifuging it heated to 5 C.

For these conditions, the duration of crystallization was 32 hours, and dB of molasses was 61.1% .40

The research results are summarized in the table. As can be seen from the table, when working on the proposed method according to compare1604855

Pass between them, equal to 0.07. At each subsequent stage of crystallization, the coefficient of penetration is maintained at 0.023 less than at

the prototype crystallization time 45 was 59.8%.

the previous, and at the last stage of crystallization in the last mash-mixer of the crystallization unit, the supersaturation ratio of the inter-crystal solution is supported by 1.025.

The massecuite obtained by this method has a DB of 78%, the duration of its crystallization is 25 hours, and molasses has a DB of 59.5%.

The research results are summarized in the table.

As can be seen from the table, when receiving the massecuite by the proposed method, as compared with the prototype, the crystallization duration decreases by 7 hours, the crystal content in the massecuite increases by 1.4%, and the molasses dB decreases by 1.6%. This also increases the quality of the sugar of the last crystallization.

Example 3. Carrying out the same way as examples 1 and 2, but before the descent from the vacuum apparatus into the receiving mixer, the mash is swung to 91.8% of the SB, the transfer coefficient of the mash solution of the massecuite in the first crystallization stage is maintained at 1.25, and the second - 1.18. At each subsequent crystallization stage, the supersaturation coefficient is kept by 0.03 less than at the previous stage, and at the last crystallization stage in the last crystallizer kneader of the crystallization unit, the supersaturation coefficient of intercrystalline massecuite solution is maintained at 1.03.

The mottle obtained according to this method has a DB of 78.1%, the duration of its crystallization is 26 hours, and DB of bladder

with

decreases by 4.5 hours, the crystal content increases by .0.6%, and dB of molasses decreases by 1.0%. At the same time, the quality of sugar of the last crystallization improves.

Example 2. The procedure is the same as Example 1, but the mash is shaken to 91.4% SB before descending from the vacuum apparatus to the receiving mixer, the supersaturation ratio of the mash solution in the first crystallization stage in the first mash mixer is 1.235, and the second is 1,165, provide differential

50

55

The research results are presented in the table.

As can be seen from the table, when obtaining a baffle according to the proposed method, in comparison with the prototype, the crystallization time decreases by 6 hours, the content of crystals in the massecuite increases by 0.9%, and dB of molasses decreases by 1.3%, while simultaneously improving sugar quality last crystallization.

When conducting research with pumping of the mash with hot water, the bottom 91% of the SAT,

the previous, and at the last stage of crystallization in the last mash-mixer of the crystallization unit, the supersaturation ratio of the inter-crystal solution is supported by 1.025.

The massecuite obtained by this method has a DB of 78%, the duration of its crystallization is 25 hours, and molasses has a DB of 59.5%.

The research results are summarized in the table.

As can be seen from the table, when receiving the massecuite by the proposed method, in comparison with the prototype, the duration of crystallization decreases by 7 hours, the content of crystals in the massecuite increases by 1.4%, and the molasses dB decreases by 1.6%. This also increases the quality of the sugar of the last crystallization.

Example 3. Carrying out the same way as examples 1 and 2, but before the descent from the vacuum apparatus to the receiving mixer, the mash is swung to 91.8% of the SB, the transfer coefficient of the mash solution of the massecuite is maintained at 1.25 at the first crystallization stage 1.18. At each subsequent crystallization stage, the supersaturation coefficient is maintained by 0.03 less than at the previous stage, and at the last crystallization stage in the last crystallizer kneader of the crystallization unit, the supersaturation ratio of the mash solution of massecuite is equal to 1.03.

The massecuite obtained by this method has a DB of 78.1%, the duration of its crystallization is 26 hours, and the DB of melas was 59.8%.

The research results are presented in the table.

From the table it is seen that when receiving the massecuite according to the proposed method, as compared with the prototype, the crystallization duration decreases by 6 hours, the crystal content in the massecuite increases by 0.9%, and the molasses dB decreases by 1.3%, while improving the quality of sugar last crystallization.

When conducting studies with the rocking of the massecuite with hot water below 91% SAT, the

the supersaturation of the intercrystal solution — the baffle at the first crystallization stage is lower than 1.22, and the second is less than 1.15, while maintaining the intercrystal solution of the massecuite permeability coefficient at each subsequent crystallization stage is lower by 0.02 than in the previous one, and at the last crystallization stage less 1.02 increases the duration of the cooling of the massecuite cooling and does not provide the necessary depletion of molasses.

When swinging the massecuite before

Claims (1)

The invention The method for obtaining the last crystallization of the massecuite, which involves boiling it in a vacuum apparatus to 94-96% CB, rocking the massecuite before descending from the vacuum apparatus with hot water and subsequent crystallization by cooling it in several steps the descent from the vacuum apparatus less than,. in agitators up to the required tempV, “Q1 OFP fn 1 IJ- TO 91.8% DM, while maintaining the supersaturation ratio of the inter-crystal solution of the massecuite in the first crystallization stage is higher than 1.25, and in the second stage it is higher than 1.18, while maintaining the crystallization coefficient in each subsequent crystallization stage is higher than 0.03 and in the latter, more than 1.03, the content of sugar in molasses and the duration of crystallization of massecuite increase. The proposed method in comparison with the prototype reduces the duration of crystallization of the massecuite by 4.5-7 hours chaffs, characterized in that, in order to reduce the sugar content in the molasses and accelerate the crystallization process, the rolls 20, before descending from the vacuum apparatus, up to 91.0-91.8% of CB is carried out, while the transfer ratio of the mash-solution of the massecuite in the first stage of crystallization in the agitator is held equal to 1.22-1.25, in the second stage - 1, 15-1.18, and at each subsequent stage of crystallization, the supersaturation coefficient of the inter-crystal solution of the massecuite is kept at 25 is kept at 1.22-1.25, at the second stage - 1.15-1.18, and at each subsequent stage of crystallization, the supersaturation coefficient of the inter-crystal massecuite solution is kept at creates conditions for increasing the content - 0.02-0.03 less than the previous MORE KPIPTYA.PPP ravana p lgAotto i-s-. . cn zhanyh sugar crystals in the massecuite by | 0.6-1.4%, provides a reduction in DB molasses of 1.0-1.6% and allows you to get sugar last crystallization at the same time, the coefficient of dissociation (yeni between the crystal solution of the massecuite at the last stage of crystallization is 1.02-1.03. better quality. These conditions contribute to a decrease in the sugar content in molasses by 0.02-0.03% by weight of the processed beets. The invention The method for obtaining the last crystallization of the massecuite, which involves boiling it in a vacuum apparatus to 94-96% CB, rocking the massecuite before descending from the vacuum apparatus with hot water and subsequent crystallization by cooling it in several steps Ij- chaffs, characterized in that, in order to reduce the sugar content in the molasses and accelerate the crystallization process, the rolls 20, before descending from the vacuum apparatus, up to 91.0-91.8% of CB is carried out, while the transfer ratio of the mash-solution of the massecuite in the first stage of crystallization in the agitator is 25.2-1.25, in the second stage - 1, 15-1.18, and at each subsequent stage of crystallization, the supersaturation coefficient of the inter-crystal solution of the massecuite is kept at  0.02-0.03 less than the previous one 0.02-0.03 less than the previous one . . cn at the same time, the coefficient of dissociation (yen of an intercrystalline solution of massecuite at the last stage of crystallization is 1.02-1.03.