Bacti - Bio 9500 (Bacti Bio 9500) is a granulated bacterial concentrate for the complete and intensive decomposition of organic matter and sediments.

APPLICATION:

Cleaning systems Wastewater- septic tanks, sand traps, sludge tanks, sewage treatment plants sewerage networks and sanitary systems - sinks, toilets commercial establishments - restaurants, bistros, canteens, shops

DESCRIPTION:

Bacti-Bio 9500 is a powder concentrate designed to degrade a wide range of substrates. Numerous microbial strains of Bacti-Bio 9500 are non-cultivated and non-pathogenic. Selected strains are active enzyme producers: amylases (starch degradation), proteases (protein degradation), cellulases (cellulose degradation), keratinases (keratin degradation), lipases (oils and fats degradation), etc. Several cultures synthesize biological surfactants .

CHARACTERISTICS:
Bacti-Bio 9500 is a white powder. pH range from 6.0 to 9.0 with an optimum of 7.5. The most effective temperature range is from 25oC. up to 55oC (77oF - 131oF) with optimum temperature around 30oC. Bacti-Bio 9500 also contains biodegradable surfactants that aid the cleaning process. Bacti-Bio 9500 contains at least 2 billion cells per gram.

ADVANTAGES:
Rapid and deep action due to the combined action of bacteria, enzymes and nutrients. Complete removal of fats and other organic deposits from sewer networks and sewage treatment plants. Quick launch of treatment facilities. Allows cleaning systems to work better and longer without maintenance. Keeps sewers clean. Controls gas emission (eliminates unpleasant smells). Long independent existence in cleaning systems.
Non-toxic and safe in contact with skin. Fats and organics

STANDARD DOSAGE

Dose of biological product Bacti-Bio 9500 (ratio 1:100) 5-7 min. dissolved in a bucket of warm water (+30 + 40°C) and kept for 10-15 minutes. to reactivate bacteria. After that, the contents are poured into the processed system.

1. Septic tanks, sand traps, rainfall tanks. Application of the first dose: 50 g/m3 is applied directly to the container. Regular maintenance: 6 g per 1 m3 of the volume of the septic chamber every two weeks. We recommend injecting the biological product more often or increasing the dose if an unpleasant odor appears or the sediment is not sufficiently decomposed.

2. Sewer networks. In order to avoid clogging and unpleasant odors, it is necessary to inject 1 dose (50 g) into 3 drains of the sewer network. Repeat the treatment after a month. In the future, apply as the clogging of sewer pipes.

3. Commercial enterprises. Maintenance dose commercial enterprises determined based on the number of meals: up to 250 meals/day 50 g/month, 250-500 meals/day 100 g/month, more than 500 meals/day 150 g/month

Treatment facilities:

Drip filters - 1.5 - 3 kg per 3780 m3 of runoff is introduced through the siphon facilities. If necessary, the initiating dose is administered again after 48 hours. For maintenance, use 0.75 - 1.5 kg of the drug per 3780 m3 of waste water. In well-aerated aerotanks 0.75-1.5 kg per 3780 m3 of waste water. Due to the high efficiency of the drug, the hydraulic delay time is significantly reduced. Silt is processed separately. Aerobic fermenters - 0.5 kg per week for 330 m3 of sludge. If there is a significant layer of fat, double the dose. Anaerobic reactors, sludge sites - the dosage is about the same as in aerobic ones. The product works harmoniously with methanogens and enhances the production of methane.

Small sewage treatment plants

Sumps - 0.25-0.5 kg per week for every 330 m3 of productivity.

Two-tier settling tanks - 0.25-0.5 kg per week for every 330 m3 of productivity. Periodic mixing is recommended.

Lagoons, post-treatment ponds (with and without aeration) - to remove odors, reduce the amount of silt, and accelerate sedimentation, enter 0.25-1 kg per 200 m3. The powder is sprayed onto the surface of the water and injected through a wet well.

Sewer lifting stations, sewer pipes and sewer lines
0.4 kg per 165 m3 of waste is introduced directly into the drain holes.

ADVANTAGES

With anaerobic and anaerobic digestion of sludge, decomposition will occur more completely, dehydration is simplified, and the amount of mineralized nutrients increases.

BIOLOGICAL CLEANING PROGRAM

The success of any biological treatment program depends on favorable operating conditions and activities. During the microbiological cleaning period, ongoing monitoring is required to ensure that the necessary operating conditions are maintained. The dose and frequency of drug administration is specific to each individual biological cleaning program.
The specifics of each situation should be analyzed in detail before designing a corrective program.
The cleaning program usually includes a more powerful start-up dose and a maintenance dose. Determination of the optimal dose is usually performed on site, reducing the frequency of dosing gradually until there is no deterioration in the effectiveness of the drug.

In addition to canning potatoes, this raw material is the main one for obtaining starch. Starch is produced at large specialized enterprises, at small factories and even in small workshops. As a raw material, you can use both ordinary ware potatoes and small ones, which, as a rule, are rejected by size during drying or freezing. The main requirement is that potatoes must be mature, since in young immature tubers the average size of starch grains is smaller, respectively, the quality of the finished starch from them will be lower, and the amount of losses during production will be higher.

On average, one tuber contains about 18% starch of the total weight. When starch is extracted, the cell walls of the raw material are destroyed, and the maximum a large number of starch grains, which are then separated from the liquid and impurities and dried. When receiving starch, cold water is used, it is dried at a low temperature. Since dry anhydrous starch has specific gravity 1.65 g per ml, then the starch grains are rapidly precipitated when separated from the pulp cells. This allows them to be caught in the form of a precipitate and separated by a centrifuge from the liquid part.

Starch production consists of several operations. First, all potatoes are washed in a special washing machine, which is equipped with a deep chute with a shaft at the top. Water consumption when washing potatoes is 4-5 cubic meters. meters of water per 1 ton of raw materials. Then, as with canning potatoes, the tubers are crushed. But this time they are crushed in such a way as to destroy the maximum amount of cell walls (this will allow you to extract as much starch from them as possible). However, excessive grinding will make it difficult to separate them from the starch and liquid. Therefore, to grind potatoes, they are passed through grating devices that turn the tubers into a mushy mass, the main part of the starch grains in which is in a free state. The mashed potato mass is collected in a collection, and then served on a sieve. Semi-cylindrical, cylindrical (rotary) and flat (shaking) equipment can be used on the line. It is here that, under the influence of water, starch grains are separated from other components of the mass. More than half of the starch passes through the sieve along with water and other substances. At the same time, pulp, fiber and about 25% starch remain on the sieve. To reduce losses, the remaining porridge is crushed again and passed through a sieve with smaller holes. Starch grains that have passed through the sieve along with water are called starch milk. The solution is drained into a separate tank, where starch is separated from the water by settling in vats, settling in a stream (on trays or in grooves) or by centrifugation. In the first case, the milk is drained into tanks and left for 7-8 hours. The starch settles to the bottom of the tank, and the liquid with the resulting foam is carefully drained through filters to trap the remaining starch in it. The starch is discharged into the washing tank, where it is again mixed with water and left to settle. The plaque formed during the secondary washing is removed from the surface of the water, and the raw starch is sent for drying. Raw contains up to 55% water. In the process of drying at a temperature of 45-50 °, the level of its humidity is reduced to 20%. Since lumps form in the starch as a result of this operation, they must then be crushed. Finally, the finished starch is sifted through burat and packaged.

On most modern enterprises automated lines for the production of starch of four varieties (extra, superior, first, second) are used. They allow you to perform all operations - washing raw materials, grinding, collecting and cleaning porridge, mechanical dehydration of the resulting starch, separation of free starch from porridge, dehydration and drying - with minimal human intervention and waste-free technology. A special hydrocyclone unit is used to separate potato porridge into a starch suspension and a mixture of pulp with potato juice.

This allows you to significantly reduce the consumption of fresh water, which in this case is about 0.5 cubic meters. meters per 1 ton of potatoes. In addition, wastewater is almost completely eliminated, and the resulting concentrated waste (with a content of about 7-10% of dry matter) is fed to livestock in natural or processed form. Such installations do not require a large production area for placement and are characterized by high productivity (up to 10-15 tons of starch per day). The cost of such a set of equipment starts from 7 million rubles. When choosing premises for production and warehouses, keep in mind that fine starch dust in the air can explode on contact with fire. Therefore, at such an enterprise, special requirements are imposed on the equipment of premises where starch is produced (especially in areas where it is dried and packaged), including compliance with fire safety rules. In addition, you will need your own wastewater treatment system or the possibility of locating filtration fields near the production. Such an enterprise should be located outside the city. You also need your own transport: potatoes are delivered to the plant from farms within a radius of 100 km. The cost of delivery alone is about 1000 rubles per 6 tons of processed potatoes or 1 ton of finished starch. To service an average production, 14-16 people working in two shifts will be required. The average salary of an employee will be about 18 thousand rubles. Thus, the cost of wages in the cost of 1 ton finished products amount to 320 rubles. Add to this the cost of purchasing raw materials (potatoes), sodium sulfate, the cost of water, electricity, gas, and the purchase of packaging (bags). With such figures, the cost of production of 1 ton of potato starch is approximately 31-32 thousand rubles.

The average market wholesale price of potato starch is about 37 rubles per kilogram. Thus, the income of an enterprise for the production of potato starch, excluding tax deductions, as well as the organization of marketing of products and other costs, except for those taken into account above, can be 3.5-4 million rubles per month with a productivity of 1-1.5 tons starch per hour. Of course, after deducting all expenses, the net profit will be an order of magnitude lower. Nevertheless, it is possible to increase the profitability of the enterprise by expanding the range, selling waste from potato processing (fiber) as animal feed, etc.

The potato canning and starch business is seasonal. Since potatoes lose most of their starch during storage, the season for processing raw materials is about 250-300 days - from September to May. But to get more starch High Quality it is recommended to process all potatoes within 200 days. Since April (and in some regions even earlier), starch losses have increased significantly.

Sysoeva Lilia
- portal of business plans and guidelines

Until 1945, the demand for starch and its products in Germany was met by the operation of 200 factories, which in the 1942/1943 season. gave about 400,000 tons of products.[ ...]

Most of the factories, which were 90% consumers of agricultural products and 10% of industrial products, were located in the eastern parts of the country and were mainly engaged in processing potatoes. Only a few industries used cereals as feedstock.[ ...]

In the 1949/1950 business year in Germany there were 12 small industries processing 1-9,000 tons of potatoes, about 10 industries processing 85,000 tons of corn, rice and millet, and about 6 industries processing 19,000 tons of wheat.[ ...]

Since in the West there is a shortage of potatoes for starch, it must be replenished by imports from other countries.[ ...]

A. Potato starch factories. Processing and drying of potatoes occupy a large place, especially in the following regions: Brandenburg, Mecklenburg-Pomerania, Lower Saxony, Saxony-Anhalt.[ ...]

Processing of potatoes begins immediately after harvesting, since during storage of potatoes, losses occur due to shrinkage, freezing and decay, which takes from 5 to 10%. It should be noted that if frozen, potatoes become unsuitable for starch production. All of the above led to the fact that potato processing began to be carried out seasonally (September - January).[ ...]

According to the Maizen patent (Ma!hep), the potato processed into starch is ground and enters the tank in the form of a thick slurry. Chemical additives prevent the decomposition and saccharification of starch. The processing of this slurry is successfully carried out even in the month of May.[ ...]

The workflow for all types of starch production is basically the same. After dry cleaning on shaking screens, the potatoes are transported by hydraulic transport to the factory. Here, the potatoes are washed in drums operating on the countercurrent principle, in which, with mutual friction and with an excess of water under pressure, they are cleaned of adhering dirt. In this case, wastewater from hydraulic conveyors and from washing potatoes is formed. The potatoes are then mashed in a rapidly rotating cylinder equipped with teeth. In the same place it is subjected to thorough washing with water. The resulting mass is crushed in brush machines or mills. An aqueous suspension containing the bulk of the potato is separated on sieves from starch milk, which is fed to re-sifting, and then to settling tanks, where starch, having a higher specific gravity, is separated from water, which is called "fruit water".[ ...]

As a result of subsequent thorough washings, the starch is completely purified. During this operation, as well as during the subsequent dehydration of starch in centrifuges, washing "starch water" is formed, having a starch concentration of up to 25C0 mg / l. With high centrifuge power, this concentration can be reduced to 25 mg/l.[ ...]

After drying the centrifuged material, the finished product is obtained. At new enterprises, instead of sieves, hydrocyclones are used, which ensure the rapid extraction of potato starch and, moreover, almost without loss. In this method, washing is carried out during operation, and the starch is concentrated to such an extent that it is taken out of the centrifuge and can go directly to the dryer.

Waste water from starch and syrup industry enterprises

The enterprises of the starch-treacle industry include plants and workshops for the combined processing of potatoes into starch and alcohol, potato starch, corn-treacle and corn-starch plants, plants for processing potatoes into dry starch and corn into dry starch.

Waste water at the enterprises of the starch and syrup industry is formed as a result of technological processes processing of raw materials from the hydraulic conveyor, washing of raw materials and equipment, cooling apparatuses, vacuum pumps, blowers, refrigerators, barometric condensers, etc.

The average annual amount of wastewater from the shops for the combined processing of potatoes into starch and alcohol on mixed raw materials (potatoes and grain) per 1 ton of dry starch with a direct-flow water supply system is 137.7 m3, including 137.0 m3 - production and 0.7 l3 household -household, and when working on potato raw materials, the costs are 200; 199.3; 0.7 m3 respectively. The coefficient of uneven flow of effluents in summer and winter is equal to one.

At corn-treacle plants with a water reuse system, the average annual amount of wastewater per 1 ton of molasses is 34.06 m3, of which 4.52 m3 is industrial, 0.24 m3 is domestic and 29.3 m3 is conditionally clean. The coefficient of uneven flow of effluents in summer and winter is equal to one.

At corn-starch plants in the production of starch with direct-flow water supply systems, per 1 ton of starch, the average annual amount of wastewater is 15.0 m3, of which 3.0 m3 is industrial, 1.5 m3 household, 10.5 m3 conditionally clean, and in the production of glucose with reuse of water per 1 ton of glucose, the consumption of wastewater is 262.2 m3, including 5.8 m3 of production, 0.4 m3 of domestic and 256.0 m3 of conditionally clean. The coefficient of uneven flow of effluents in summer and winter is equal to one.

During the processing of potato raw materials, conveyor-washing waters are formed, and during the processing of wheat, corn, rice, wastewater from the pre-treatment of grain, i.e. water of locking or swelling as a result of the chemical treatment of corn with sulfurous acid, and rice with caustic soda.

Wastewater from the starch and syrup industry can be divided into four categories: trapsporterio-washing, juice, washing and pressing.

Conveyor-washing water is formed during hydrotransport and potato washing. Their number depends on the degree of contamination of the potatoes, the type of washing machines and is 1300-1400% of the weight of the processed potatoes. In relation to the total flow of the plant, these waters make up 55%.

Contaminants in the conveyor-washing waters of potato-starch plants consist of soil washed from tubers, small potatoes, tops, potato sprouts, and straw. The amount of contamination is 5-20% of the potato weight. When washing a healthy potato, its dry matter is not washed out and almost not lost, but it gives off suspended and soluble substances, and rotten and frozen potatoes give up part of the dry matter.

At the beginning of the raw material processing season, starch plants primarily process potatoes that are not suitable for long-term storage: clogged, wet, frozen, damaged by rot. In winter, the best quality potatoes are usually processed, and in the spring - germinated, affected by rot. This causes significant pollution of wastewater in the autumn and spring periods of operation of potato processing enterprises.

The amount of conveyor-washing wastewater is from 6 to 8 m3 per 1 ton of potatoes with a decrease to 5 in case of reuse on a hydraulic conveyor.

The amount of contamination of conveyor-washing water, mg/l:

1. Earth (inorganic suspensions) - 750
2. Organic - 230
3. Inorganic soluble - 200
4. Organic soluble - 190
5. Nitrogenous substances - 150
6. BOD5 - 152

The composition of conveyor-washing water in different seasons of work is not stable and is characterized by large fluctuations (Table 26).

Table 26. Composition of wastewater, mg/l, Shatsk potato starch plant (Belarus)

Conveyor-washing waters have a yellow-brown color, an earthy-potato smell; pH = 6.5; suspended solids - 950 - 30600 mg / l in autumn and 600-4700 in spring; BOD5 - 100-500 mg/l in autumn and spring, bichromate oxidizability 500-2000 mg/l in autumn and 300-1300 mg/l in spring.

Conveyor-washing water and washing water in common complex wastewater from potato-starch plants are diluting, as they contain lower concentrations of contaminants compared to juice press water.

Juice waters are liquefied potato cell juice. They are formed by separating starch in sedimentary centrifuges and washing it in hydrocyclones or washing tanks. The amount of juice water is 7-12 m3 per 1 ton of processed potatoes and depends on the capacity of the plant.

Pollution consists of a large amount of organic soluble and insoluble substances capable of putrefaction and fermentation, as well as a small amount of inorganic salts of potassium and phosphoric acid. characteristic feature of this wastewater is fermentation. In the process of fermentation, lactic, butyric acids are formed and an unpleasant odor is released. The fermentation process ends with rotting with intense release of hydrogen sulfide.

Depending on the operating conditions of the enterprise, the concentration of juice water ranges from 0.6-1.0% -

The solids content of juice water includes up to 15% mineral, 35-40% nitrogenous and protein compounds, approximately 10% starch, 20-25% soluble sugars, 3% fat and up to 15% other substances.

By chemical composition juice water is an organic, predominantly nitrogen-potassium fertilizer. According to the content of the main nutrients (nitrogen, potassium, phosphorus), 1000 m3 of juice water is equal to a mixture of 15 q of ammonium sulfate, 5 q of superphosphate and 12 q of 40% potassium salt. In addition to soluble substances, juice water contains no more than 0.015% pulp and starch.

Wash water is formed during the washing of starch. Their quantity is insignificant 1-3 m3 per 1 ton of processed potatoes. The content of pollutants in wash waters is insignificant, since most of them leave with juice waters. The contaminants consist of potato solubles and a relatively small amount of fine pulp and starch particles.

Press waters appear as a result of pressing the pulp by washing it. The amount of press wastewater is 0.4-0.6 m3 per 1 ton of potatoes. The composition of pollution of these wastewaters is similar to the composition of pollution of juice waters.

The formation of the general flow of the enterprise, the nature and extent of pollution depend on individual technological processes, sources of wastewater generation, and their pollution. For example, the amount of wastewater from potato processing depends mainly on the peeling technique. When cleaning with the use of caustic soda, wastewater has a pH = 10-11.

With the steam or abrasive method, this figure is much lower.

The specific wastewater consumption per unit of produced projection for plants operating on mixed raw materials (potatoes, grain) is 140 m3, and for potato - 200 m3 per 1 ton of dry starch.

In the production of potato starch, wastewater has suspended solids 1500-5000 mg/l, average mineralization 1800-3500 mg/l, bicarbonate-sulfate composition, acid reaction of the medium, pH = 4.2-4.8. The nitrogen content averages 120 mg/l, potassium - 300, phosphorus - 15, calcium - 80 mg/l. The composition of wastewater is unstable, with a large amplitude of fluctuations.

The total runoff of enterprises processing potatoes for starch is characterized by the following pollution levels: suspended solids 2500–18000 mg/l, BODb 1100–1500 mg/l. At the same time, the composition of suspended solids, mg / l, is: the total amount is 2824, including organic - 1454, total nitrogen - 265, phosphorus - 93, potassium - 486.

Wastewater from starch enterprises has a large amount of organic, biologically (biochemically) treatable contaminants. Their concentration of carbohydrates and proteins is higher than that of domestic wastewater. They are a little transparent, in a fresh state they have a slightly alkaline and in rare cases an acid reaction of the environment. The decrease in pH can be attributed to the development of lactic and butyric acid fermentation in wastewater. The decomposition of proteins is accompanied by the release of hydrogen sulfide.

Wastewater from the production of starch from corn, wheat, rice differs from wastewater from potato-starch production by a higher content of sodium salts and organic substances, a less acidic reaction of the medium, and a variable composition.

In the production of starch using corn as a raw material, wastewater is generated in the amount of 24-28 m3 per 1 ton of starch. This amount does not include wastewater from pre-treatment of grain, t. from locking and swelling, as they are processed in evaporators with subsequent use for livestock feed or as a feedstock for the production of penicillin.

Due to the variety of its properties, the ability to change them, starch is used in various food production(confectionery, bakery, sausage, etc.), in cooking, for the production of starch products, in non-food industries (perfumes, textiles, etc.).

Calorie content of 100 g of starch is 350 kcal. In plant cells, starch is in the form of dense formations called starch grains. Starch grains of different plants are characterized by a certain shape, structure, size. Based on these features, you can determine the type of starch. Starch can be made using various plant materials. At the same time, the production technology is slightly different. In this article, we will describe the technology for the production of starch from potatoes and corn.

Potato starch production

From dirt and foreign inclusions, potatoes are washed in a potato washing machine, then served for grinding. The more crushed it is, the more complete will be the release of starch from the cells, but it is important not to damage the starch grains themselves. First, the potatoes are crushed twice on high-speed potato graters. The principle of their action is to abrade the tubers between the working surfaces formed by fine-toothed files fixed on a rotating drum. On the graters of the first grinding, the files protrude above the surface of the drum by 1.5 ... 1.7 mm, on the graters of the second grinding - no more than 1 mm. During the second grinding, 3 ... 5% of starch is additionally extracted. The quality of chopping also depends on the condition of the potatoes (fresh potatoes are chopped better than frozen or sluggish ones).

After crushing the tubers, which ensures the disclosure of most of the cells, a mixture is obtained, consisting of starch, almost completely destroyed cell membranes, some intact cells and potato juice. This mixture is called potato porridge. Starch remaining in unbroken cells is lost with the by-product of production - potato pulp. This starch is commonly called bound, and the one isolated from potato tubers is called free. The degree of potato chopping is estimated grinding factor, which characterizes the completeness of cell destruction and the amount of starch extraction. It is determined by the ratio of free starch in the porridge to the total starch content in the potato. During normal operation, it should not be less than 90%. To improve the quality of starch, its whiteness and prevent the development of microorganisms, sulfur dioxide or sulfurous acid is added to potato porridge.

The composition of the nitrogenous substances of the juice includes tyrosine, which, under the action of the tyrosinase enzyme, is oxidized to form colored compounds that can be sorbed by starch grains and reduce the whiteness of the finished product. Therefore, the juice is separated from the porridge immediately after grinding. Hydrocyclones are used to extract sand from the starch suspension and separate the pulp with potato juice. The principle of their operation is based on the centrifugal force that occurs during rotation. As a result of processing, a starch suspension with a concentration of 37 ... 40% is obtained. They call her raw potato starch.

For drying starch, continuously operating pneumatic dryers of various designs are most often used. Their work is based on the principle of drying loosened starch in a moving stream of hot air. The yield of finished starch depends on its content in the processed potatoes and on the loss of starch with by-products and wastewater. In this regard, the starch content in potatoes supplied for processing is normalized by the standard and should be at least 13 ... 15%, depending on the cultivation zone.

In the production of starch, its release is provided in two forms: dry and raw potato starch. The amount of raw potato starch is determined in accordance with OST 10-103-88. There are raw starch grade A and grade B with a moisture content of 38 and 50%, respectively. Depending on the quality (color, inclusions, foreign smell), raw starch is divided into three grades - the first, second and third. Raw starch is a perishable product and is not subject to long-term storage; sulfur dioxide of 0.05% concentration can be used for conservation.

Dry starch is packaged in bags and small packages. Potato starch is packed in double fabric or paper bags, as well as bags with polyethylene liners weighing no more than 50 kg. In terms of quality, starch, in accordance with the requirements of GOST 7699-78, "Potato starch" is divided into the following grades: "Extra", highest, first and second. Moisture content of starch should be 17…20%, ash content 0.3…1.0%, acidity 6…20° depending on the variety. The content of sulfur dioxide is not more than 0.005%. Important indicator, characterizing the purity and whiteness of starch, is the number of specks per 1 square dm when viewed with the naked eye. For "Extra" - 80, for the highest - 280, for the first - 700, for the second it is not standardized. Starch of the second grade is intended only for technical purposes and industrial processing. Guaranteed shelf life of starch is 2 years from the date of production at a relative air humidity of not more than 75%.

Corn starch production

In general terms, the processing of corn can be described as follows: peeled corn is softened in hot water containing sulfur. With coarse grinding, the germ is separated, while with fine grinding, fiber and starch are separated. The mill effluent is cleaned of gluten and washed many times in hydrocyclones to remove the last traces of protein and produce quality starch.

CLEANING.The raw material for wet grinding is threshed corn. Grain is checked and removed cobs, straw, dust and foreign materials. Usually cleaning is carried out twice before grinding. After the second cleaning, the corn is divided into portions by weight and placed in bunkers. From the hoppers, it is hydraulically fed into the key vats.

SOAK.Proper soaking is necessary condition high output and good quality starch. The soaking is carried out in a continuous countercurrent process. Peeled corn is loaded into a battery of large locking containers (vats), where it swells in hot water for about fifty hours. In fact, steeping is a controlled fermentation, and adding 1000-2000 ppm sulfur dioxide to the key water helps control this fermentation. Soaking in the presence of sulfur dioxide directs fermentation by accelerating the growth of beneficial microorganisms, preferably lactobacilli, while suppressing harmful bacteria, molds, fungi and yeasts. Soluble substances are extracted and the grains are softened. The grains more than double in volume, their moisture content increases from about 15% to 45%.

Scheme of grain soaking at a plant with a capacity of 150 tons of corn per day

EVAPORATION OF KEY WATER. The key water is drained from the grain and condensed in a multi-stage evaporator. Most of the organic acids formed during fermentation are volatile and evaporate with water. Therefore, the condensate from the first stage of the evaporator plant must be neutralized after heat recovery by heating the water supplied for soaking. Depleted key water, containing 6-7% solids, is continuously removed for subsequent concentration. Key water condenses into a self-sterile product - a nutrient for microbiological industry, or concentrated to approximately 48% solids and mixed and dried with fiber.

SO2 PRODUCTION.Sulfurous acid is used to soak and soften the corn and control microbiological activity during the process. Sulfur dioxide is produced by burning sulfur and absorbing the resulting gas with water. Absorption takes place in absorption columns where the gas is sprayed with water. Sulfurous acid is collected in intermediate tanks. Sulfur dioxide can also be stored in pressurized steel cylinders.

DEPARTMENT OF THE GEM . Softened grains are destroyed in abrasive mills to remove the shell and break the bonds between the germ and endosperm. Water is added to support the wet grinding process. A good soaking ensures that the intact germ can be freely separated from the beans during a gentle grinding process without any oil release. The oil is half the weight of the embryo at this stage, and the embryo is easily separated by centrifugal force. Light embryos are separated from the main suspension on hydrocyclones designed to separate the primary embryo. For complete separation, the product stream with the remains of the germ is subjected to repeated grinding, followed by separation on hydrocyclones, which effectively removes the residual - secondary - germ. The germs are repeatedly washed in countercurrent on a three-stage sieve to remove starch. Pure water added in the last step.

Germ separation in a plant with a capacity of 150 tons of corn per day