Functioning Installations

Structural and technological solutions for CW and tertiary plants have been worked out on 24 existing facilities:
villa community of Nazran, the airport in Magas (Ingushetia), p.p Severino, Gazyr (Krasnodar region.) village Kovalevka (Rostov region.), Kresty (Moscow region.), National Bank of Ossetia etc. with initial concentration of wastewater BOD₅ 180,0-2100,0 mgO₂/l, suspended solids 140,0-700,0 mg/l and ammonia nitrogen 31,0-147 mg/liter. Treatment effect within BOD₅ and suspended solids was 96-99%, removal of ammonia nitrogen was 75-92%.

In the sewerage systems of villages and small towns with a significant length of automatic flow tank and pressure reservoirs the sulphide and hydrogen sulphide content increases to 5,0-40,0 mg/l, of ammonia nitrogen content-to 50,0-100,0 mg/l. It happens due to the processes of organic contaminants decay in collectors and receiving tanks of pumping stations, and the delivery of sewage from septic tanks and cesspools. The processes of sulphat reduction and ammonification become especially active in warm time of year.
In the process of methane fermentation in anaerobic bioreactors for treatment of concentrated wastewater in yeast plants, breweries, sugar refineries, pulp and paper plants the sulphide and hydrosulphide content increases to 10 ... 100 mg/l, and pH level decreases to 4-5.
Hydrogen sulfide is an enzyme poison and its content in waste water, fed to the biological treatment, is limited to 2 mg/liter.
In the wastewater of Kushchevskaya village, Krasnodar region content of BOD is 230-350 mg/l, this of hydrogen sulfide and hydrosulfides is 21-42 mg/l, and ammonium nitrogen-35-100 mg/liter. Applying thin mechanical treatment installations instead of primary sedimentation tanks helped to avoid further decay of the waste. Hydrogen sulfide removal in CW biofilters and the formation of adapted microflora ensured complete hydrosulfides sorption and oxidation. Reduction of organic impurities within BOD is 8-12 mg/l, the transparency of the purified water is 28-30 cm according to Snellen.