Wastewater treatment plants – engineering structures of the sewerage system for treatment, disposal, disinfection of wastewater with the possibility of their further use or release into water bodies.
Wastewater treatment plants in individual settlements or individual facilities are designed taking into account the consumption of wastewater per day of the greatest drainage and the total amount of pollutants in all categories of wastewater entering these treatment plants. The degree of wastewater treatment is determined depending on local conditions, taking into account the possible use of treated wastewater and surface runoff for industrial or agricultural purposes. The degree of treatment of wastewater discharged into water bodies must meet the requirements of the current “Rules for the protection of surface water from pollution by return water”, approved by the Cabinet of Ministers № 465.
Sewage treatment projects consist of the following main sections:
- Software -General explanatory note;
- GP – General plan;
- AB – Architectural and construction solutions;
- KB – Building constructions;
- TC – Technological solutions;
- OV – Heating and ventilation;
- ET – Electrical solutions;
- ZK – External sewerage networks;
- POB – Construction Organization Project;
- EIA – Environmental Impact Assessment or EIA;
- SPZ- Fire safety systems;
- ITZ – Engineering and technical measures of civil protection;
- K- Estimate documentation.
The technology of domestic wastewater treatment is based on the use of mechanical (settling), biological (aerobic oxidation) methods.
Preliminary mechanical wastewater treatment is carried out on a mechanical rake-type lattice with 10 mm transparent seals with a screw device, which are designed to remove coarse impurities and substances floating on the surface from wastewater. The removed coarse impurities are removed to the container and sent to the composting site.
To remove from wastewater medium and small wastes, easily deposited mineral particles (sand) larger than 0.15-0.20 mm, wastewater passes through sand traps. Sand is removed to sandy areas. After drying, the sand is subject to removal to places designated by local governments, and approved by the sanitary-epidemiological station and the Department of Ecology and Natural Resources. Dehydrated sand can be used to rehabilitate eroded areas.
Biological wastewater treatment takes place in aeration tanks, where the destruction of proteins, fats, carbohydrates, surfactants, ammonia, amino and amide compounds by bacteria and protozoa, which are in both immobilized and free-floating state.
Dephosphotization of wastewater occurs by dosing a solution of coagulant in the pipeline drain decantate from the unit of mechanical dehydration of sludge (dehydrators). Decantate from dehydrators together with a dose of coagulant enters the head of treatment facilities and thus helps to remove phosphorus.
Additional treatment of biologically treated wastewater takes place in existing bioponds.
Disinfection of wastewater is provided by an electrolytic solution of sodium hypochlorite, the preparation of which takes place by electrolysis of a solution of salt and water.
The sludge treatment unit includes sludge stabilization in an aerobic stabilizer, compaction, dehydration on a screw dehydrator and sludge disinfection with quicklime. At the outlet after the dehydrator, the dehydrated sludge has a humidity of 75-80% or less, depending on the composition of wastewater. The dehydrated sludge is removed to a container and fed to a composting site.
The equipment involved in the wastewater treatment process is constantly being improved, and research is being conducted in this area for greater efficiency and effectiveness of treatment facilities.
We will design qualified treatment facilities according to your requirements. We offer the use of the best available technologies, which will give the most efficient wastewater treatment at the lowest cost of the treatment complex.