Sewage treatment removes contaminants from sewage. It includes physical, chemical, and biological processes. Its objective is to produce an environmentally safe fluid waste stream (or treated effluent) and a solid waste (or treated sludge) suitable for disposal or reuse (usually as farm fertilizer).
The Sewage Treatment is designed to filter domestic waste water, which can be reused for gardening / miscellaneous purposes.
Following stages are involved in treatment of Sewage Water
Screen Chamber - Sump - Grit Chamber - Aeration Tank - Clarifier - Chlorine Contact Tank - Graded Sand Filter - Activated Carbon Filter - Treated water tank.
The above stages are tentative and can be changed as per the input conditions & the desired output conditions. An UF / RO can also be provided so as to make the water suitable for process / reuse.
Sewage can be treated close to where the sewage is created, a decentralized system (in septic tanks, bio filters or aerobic treatment systems), or be collected and transported by a network of pipes and pump stations to a municipal treatment plant, a centralized system.
Sewage treatment generally involves three stages, called primary, secondary and tertiary treatment similar to the wastewater treatment, with an additional disinfection step as follows:
The purpose of disinfection in the treatment of waste water is to substantially reduce the number of microorganisms in water, to be discharged back into the environment for later use in irrigation, etc.