Waste water

Wastewater - water that is contaminated as a result of their use in the home or the workplace. Wastewater is removed from settlements through the sewage network. Waste water are divided into: a) storm; b) sanitary; C) production.
Wastewater treatment is their neutralization and disinfection. First, wastewater lighten, freeing them from the precipitate (mechanical treatment), and then clarified water oxidizes by means of biological treatment (biological treatment).
Biological treatment is carried out by two methods: 1) intensive (artificial cleaning) and 2) extensive (natural cleaning). Intensive method allows you to clean the liquid waste for special treatment facilities, located on a small territory, but now costs of electricity, construction of treatment facilities, trained personnel to manage and chlorination. Extensive method requires a large area but less expensive in construction and operation and gives Stoke-free eggs of helminthes and pathogenic bacteria. Chlorination in this case is not required.
The buildings of intensive cleaning includes aeration tanks and biochemical (biological filters, percolator). The aeration tank is a concrete tank, which is supplied compressed air. In the process wastewater aeration them into active sludge, which is compact cereals, richly populated microbial flora and protozoa water organisms. Active sludge adsorbs, oxidizes and mineralizes organic matter wastewater.
Percolator are tanks filled with slag, stone crushed stone, coke or other filter material. On top of it come clarified waste water and bottom under pressure compressed air; the oxidation of organic substances is carried out by means of algae, protozoa, bacteria and worms.
The extensive facilities include cleaning biological ponds, irrigation fields () and scratch filter (PF). Biological ponds are shallow earthen reservoirs through which very slowly waste water flows. In wastewater develop biochemical processes, analogous to the processes of natural self-purification. Field irrigation and filtration fields - the land on which waste water coming to the natural biological treatment in the soil. In the fields of irrigation occurs as wastewater treatment, and the cultivation of various agricultural crops; smaller area require a filter field, where only wastewater treatment.
The waste water of the majority of factories and plants effectively cleared by biology. So, by natural means well-disposed wastewater from the food industry, as well as those enterprises that process easily degradable organic matter. For sewage treatment of a number of enterprises (radiological objects and other) special treatment plants.
Control over the efficiency of sewage treatment is carried out directly at the stations of cleaning and agreed with the bodies of the sanitary and epidemiological service. The nature and timing of the control analyses depend on the composition of waste water, cleaning methods, sanitary significance of the reservoir - receiver wastewater.
Place of sampling for tests: 1) the incoming waste water treatment plants; 2) intermediate stages of cleaning; 3) extending wastewater (definition of efficiency of purification). Wastewater samples are taken not single and daily average or medium proportional (for the change in enterprises). Control over the efficiency of treatment of sanitary wastewater is carried out by reducing the biochemical oxygen demand (BOD5), oxidation, ammonia nitrogen, suspended solids, total number of bacterial Metropol, Escherichia coli and increase of nitrates and nitrites. Evaluation of the received data must be conducted in accordance with the "Rules of surface water protection from pollution by sewage, approved by the USSR Ministry of health on 15 July 1961 № 372-61.
Chlorination of sewage. To gloriagate should only be clarified or biologically treated wastewater, as chlorination of untreated wastewater does not give reliable bacteriological effect. The dose of chlorine for clarified waste water is 30 mg/l, and for biologically treated 10 mg/L.
The descent of sewage into water bodies must be located downstream from the borders of the settlement. The descent was carried out in such a way as to ensure the most complete mixing of sewage water reservoir in the place of issue of wastewater. However, consider the impact of wastewater discharges on the regime of the reservoir in the area downstream of the settlement.