RU2215040C1 - Method for preparing nutrient water for diffusion - Google Patents

Abstract

FIELD: sugar industry. SUBSTANCE: method relates to production of sugar and involves alkalinization of mixture of ammonia and barometric water with milk of lime and deammonization. Then water is saturated, formed precipitate is removed and sulfinated. Deammonization and saturation of mixture is carried out simultaneously at pH 7.7-8.3. Sulfitation of nutrient water is carried out to pH 6.4-6.5 and then binary non- ammonizated superphosphate in the amount 0.02-0.04% to water mass is added to sulfinated water. Invention provides minimal amount of ammonia, reduction of microorganisms content and other impurities and improvement of quality of diffusion juice as result of diffusion using. EFFECT: improved preparing method.

Description

 The invention relates to sugar production and can be used to extract sucrose from beet chips.

 A known method of preparing feed water for diffusion apparatus, comprising introducing calcium hydroxide into barometric water or condensate, sulphitating, passing air containing ozone through sulphitated water (RU 2008357 C1, C 13 D 1/08, 02.28.94).

 The disadvantage of this method is that the use of ozone greatly complicates the process of preparing water, as it requires installation of the plant to receive ozone and its qualified maintenance, strict adherence to safety measures during its operation. The use of ozone also causes increased chemical corrosion of metal parts of apparatus and pipelines.

 The closest analogue to the proposed method is a method of preparing feed water for diffusion apparatus, comprising alkalizing the mixture of ammonia and barometric water with lime milk in an amount of 0.23-0.27% CaO to the mass of water, while air is used for de-ammonization, saturation to pH 9, 5-9.7, mixing with pulp water to a pH of 7.8-8.1, holding for 6-10 minutes, sulfonation to a pH of 6.0-6.2 (RU 2135587 C1, C 13 D 1/10, 08/27/99).

 The disadvantage of this method is that the addition of pulp press water to the feed water for diffusion apparatus leads to an increased content of microorganisms and various non-sugars in the feed water, which reduces the efficiency of the diffusion process.

The technical result in the proposed method is achieved by the fact that in the preparation of feed water for the diffusion process, the mixture of ammonia and barometric water is heated to 80-85 ^o C, alkalized with milk of lime to pH 11.0-11.3, the water is simultaneously treated with steam-air mixture and saturation gas to a pH of 7.8-8.3, sediment separation, sulfonation to a pH of 6.4-6.5, the introduction of double non-ammoniated superphosphate into water in an amount of 0.02-0.04% by weight of water.

 The method is as follows.

The mixture of ammonia and barometric water is heated to a temperature of 80-85 ^o C and then alkalized with milk of lime in an amount of 0.20-0.25% CaO to the mass of water to achieve a pH of 11.0-11.3. After that, the water mixture is simultaneously treated with a steam-air mixture and a saturation gas. The flow rate of the steam-air mixture for water treatment is 0.018-0.020 m ³ / m ² s. The use of a vapor-air gas mixture for de-ammonization makes it possible to maintain a constant temperature of simultaneous de-ammonocarbonization in the apparatus and to intensify its process. The particles of calcium carbonate formed during carbonization purify water from impurities by adsorption.

 The pH value of water after deammocarbonization is 7.8-8.3. With a deeper resaturation to a pH below 7.8, the effect of subsequent sulfitic water treatment will decrease, during which the maximum suppression of harmful microflora is achieved. With a small degree of saturation (pH above 8.3), the efficiency of adsorption treatment of water with calcium carbonate decreases and there is a real possibility of disrupting the normal technological mode of the diffusion plant, because achieving the optimum pH value of feed water in one step of sulfitation becomes very problematic.

 Sedimentation of the suspension is carried out in the sump, from which the decantate is fed to sulfitation in order to reduce the pH to 6.4-6.5. At a lower or higher pH on sulfitation during the subsequent addition of non-ammoniated superphosphate to the amount of 0.02-0.04% by weight of water, the final pH of the feed water will also change, i.e. it will reach the optimal interval of 6.0-6.3.

 The consumption of double non-ammoniated superphosphate in an amount of 0.02-0.04% by weight of water is explained by the fact that this amount is quite enough to reduce the pH of water by 0.2-0.3 units and create a sufficient mass of calcium salt of phosphoric acid, which blocks the transition of pectin substances in juice and increasing the elasticity of beet chips (Bobrovnik L.D. Physicochemical principles of purification in sugar production. Kiev: Vishka school, 1994, 256 pp.). A higher consumption of double non-ammoniated superphosphate is impractical because the cost of preparing the water will begin to increase faster than the efficiency of the result. In addition, phosphoric acid salts that enter the juice with water and then progressively predefect will contribute to the formation of carbonate-phosphate adsorbent during predefection, which has a higher effect of removing negatively charged non-sugars of diffusion juice.

 Example 1. The preparation of feed water is carried out according to the proposed method.

To a mixture of barometric and ammonia water with a temperature of 82 ^° C, milk of lime is added in an amount of 0.2% CaO to the mass of water and subjected to deammocarbonization, i.e. simultaneous treatment with a steam-air mixture and a saturation gas to a pH of 8.0. Deammocarbonized water is defended, sulfonated to a pH of 6.4. Then add 0.03% to the mass of water double unmononated superphosphate and the resulting water is used for diffusion.

Beet is produced from beets, the length of 100 g of chips is 14 m, which is desugared in a continuously operating diffusion semi-industrial unit for 80 minutes at a temperature of 72 ^o C. The feed water consumption for diffusion was 120% by weight of beet chips.

Diffusion juice has the following indicators: the purity of diffusion juice H _ds 88.4%; the cleaning effect on the diffusion of E. _d 19.4%.

 Example 2. The preparation of feed water is carried out by a known method.

 To a mixture of barometric and ammonia water, lime milk is added in an amount of 0.2% CaO to the mass of water. It is treated with ozone-containing air for 12 minutes and sulfonated to pH 6.8.

The resulting feed water is used for the diffusion of juice from beet chips in a semi-industrial diffusion plant. Beet is produced from beets, the length of 100 g of chips is 14 m, which is desugared in a continuously operating diffusion semi-industrial unit for 80 minutes at a temperature of 72 ^o C. The feed water consumption for diffusion was 120% by weight of beet chips.

Diffusion juice has the following indicators: the purity of diffusion juice H _ds 87.6%; the cleaning effect on the diffusion of E. _d 14.0%.

 When using feed water for diffusion obtained by the proposed method, the purity of diffusion juice increased by 0.8%, the cleaning effect on diffusion increased by 5.4% compared with the prototype.

Claims (1)

 A method of preparing feed water for diffusion, which provides alkalization of a mixture of ammonia and barometric water with lime milk, de-ammonization of the mixture, its saturation, removal of sludge and sulfitation of feed water, characterized in that de-ammonization and saturation of the mixture are carried out simultaneously to pH 7.7-8.3, wherein sulfonation of feed water is carried out to a pH of 6.4-6.5 and then double non-ammoniated superphosphate is introduced into sulfitated water in an amount of 0.02-0.04% by weight of water.