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Cleaning and disinfection of water
If drinking water does not meet the requirements of SanPiN, then it is cleaned and disinfected. Purification aims to improve the organoleptic, physical, less chemical and even less biological properties of water. Cleaning includes its clarification and discoloration by coagulation, sedimentation and filtration. Coagulation - the process of enlarging the smallest colloidal and suspended particles, the formation of large flakes. Coagulation is carried out to accelerate the deposition and filtration processes. Coagulants are used - aluminum sulphate at a dose of 30 to 300 mg / l of water, depending on its pH. It is added to water as a powder or 2-5% aqueous solution. To speed up coagulation, soft water is alkalized with hydrated lime or soda. For this, high-molecular substances (flocculants) are also used.
Settling - clarification of water by sedimentation of suspended impurities. To do this, pass water at low speed through special sumps artificial (horizontal; vertical and radial) or natural (lake). In horizontal water moves along the trench, in vertical bottom-up, radial - from the center to the periphery of the round settling tank at a slowing rate, the sediment is removed by bottom scraper and removed from the bottom through the pipe. After coagulation and settling, small particles can remain in the water, which are retained on the filters in special installations. Slow filters are used more often: sand is on top (0.8-1.2 m) with a layer, then the underlying layer (cobblestone and gravel with a layer of 0.6-0.9 m) and bottom drainage channels or pottery pipes, brick channels. In the process of filtering, a biological film (plankton and bacteria) is formed on the surface, which over time increases the resistance, so it is periodically removed by scrapers 2-3 cm manually 1 time in 1.5-2 months.
After cleaning, the water is clarified and released by 20-25% of microbes. Therefore, it is disinfected.
Disinfection is the killing of microflora by various methods: thermally (boiling), physically (ultrasound, radioactive radiation, ultraviolet rays), oligodynamics (exposure to noble metal ions and oxidizers (chlorine, ozone, sodium hypochloride, potassium permanganate, hydrogen peroxide, etc.).
Water is chlorinated with gaseous chlorine or bleach containing 25-39% of active chlorine. Chlorine gas is supplied from cylinders under pressure up to 0.8 M Pa into chlorination cards, where it mixes with water and is aged for 45-60 minutes. In the water used for drinking purposes, the residual free chlorine should be 0.2-0.5 mg / l, if it is more, then the water stinks with chlorine and the animals will not drink such water, therefore it is dechlorinated with sodium thiosulfate (hyposulfite) or sodium sulfate.
Water is chlorinated in wells using dispensing cartridges made of porous ceramics. Cartridge capacity 0,25; 0.5 and 1 liter with bleach 150, 300, 600 - respectively, where 100-300 ml of water are added and mixed, stoppered and immersed for 20-30 days in water at a distance of 20-25 cm from the bottom. Yust method: press a full bleach into a 3-liter glass jar and throw it into the well - when water is analyzed, active chlorine appears in the well water, chlorinating it with residual active chlorine in the range of 0.1-0.5 mg / l.
Disinfection with bactericidal ultraviolet rays by mounting UV lamps into the water flow: DRT-1000, DB-60, RKS-2.5, installation OV-3N, OV-1P, OV-1P-RKS, OV-AKH-1, OV-3P -Rks. OVU-6P and UOV-5N installations are designed for agricultural water supply.
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Cleaning and disinfection of water
- Cleaning and disinfection of water
To improve the quality of water used: Water purification (clarification and discoloration): - settling (mechanical method); - filtering (physical method); - coagulation (chemical method) - sedimentation in the form of larger particles of suspension Water disinfection (destruction of microorganisms): - chlorination - with gaseous chlorine or bleach (chemical method): up to 0.3-0.5 mg / l;
- The water supply is local and central. Sanitary protection of water sources. Cleaning and disinfection of water
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- Methods to improve the quality of drinking water. Disinfection of drinking water at centralized water supply and in field conditions
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- Drinking water disinfection
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- The chemical composition of water. Water pollution: physical, chemical, bacteriological. The ability of water sources to self-purification
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- PROCEDURE FOR PROCESSING MEAT AND MEAT PRODUCTS TO BE DECONTAMED
Meat and meat products obtained from the slaughter of customer-supplied livestock at the enterprises of the meat industry and consumer cooperatives, recognized as edible only after they have not been harvested, cannot be given (returned) to the owner in non-disinfected form. At enterprises that do not have special equipment for disinfecting meat and meat products, autoclaves should be installed,
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Depending on the technology of keeping animals, they receive litter manure (humidity 68-85%), semi-liquid (humidity 86-92%), liquid (humidity up to 97%) and manure drains (humidity more than 97%). Removal, processing, storage, transportation and use of manure is carried out taking into account the requirements of environmental protection, ensuring maximum cleanliness of the premises and the recommended
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