What is Decentralized Wastewater Treatment?

Decentralized wastewater treatment systems are an appealing alternative for tackling the challenges of water pollution and shortages in emerging countries' fast andurbanizing cities. They've gotten a lot of press because of their low operating and maintenance costs and smaller size investments.

Decentralized wastewater treatment systems could be a viable option for places that are not connected to sewage networks as well as newly built areas where infrastructure construction is insufficient, not ready, or will be completed in the future.

There are many scales of decentralization depending on the size of the served area:

-  Small towns benefit from decentralization at the level of a suburb or satellite township in an urban area.

-  Neighborhood-level decentralization— this group comprises clusters of dwellings, gated communities, tiny districts, and vacuum sewer-served areas.

-  Decentralization at the 'on-site' level (on-site sanitation) — Here, the entire system is contained within one property and serves one or more buildings.

Limited treatment capacity can be supplemented by decentralized and low-cost wastewater treatment systems. The government must push for the mainstreaming of decentralized wastewater treatment systems at the policy level.

Small, individual or cluster wastewater treatment facilities provide wastewater treatment services to households in decentralized systems. Wastewater can be treated onsite using aerobic and anaerobic processes in decentralized wastewater treatment systems. Settlers, baffle reactors, and anaerobic filters make up the anaerobic modules. Horizontal planted gravel filters and polishing ponds are included in the aerobic modules. This method is based on a variety of natural therapy strategies that are combined in various ways depending on the situation. Both "grey" and "black" residential wastewater is recycled with it.

What all is included in these Systems?

These systems include the following:

· Pre-treatment and sedimentation in a settlement tank or septic tank are examples of primary treatment.

· Baffled reactors for secondary anaerobic treatment;

· In the reed bed system, there is a tertiary aerobic/anaerobic treatment, as well as polishing in the ponds.

Primary Treatment: In a grease trap, the first treatment is done to screen and separate the floating oil and grease. The liquid element of the waste is separated from the solid part of the waste by a sedimentation process in a settler or septic tank. Anaerobic digestion stabilizes the settling sludge.

Secondary Treatment: Secondary wastewater treatment takes performed in Baffled Reactors, which are made up of a series of chambers through which wastewater travels upstream. Activated sludge is kept at the bottom of each chamber. During intake into the chamber, wastewater is vigorously mixed with the sludge, inoculating it with wastewater organisms that break down the contaminants contained inside.

Tertiary Treatment: The planted Gravel Filter receives tertiary treatment via the root zone system. Biological conversion, physical filtering, and chemical adsorption are the principal removal processes.At this point, the treated water meets the requirements for horticulture/irrigation water recycling and reuse.

Polishing Ponds: Both aerobic decomposition and pathogen clearance occur here. Fish farming is achievable in big and low-loaded polishing ponds. It is easy in construction, reliable in performance if properly designed, has high pathogen removal and can be used to create an almost natural environment.

For design, installation and manufacture of waste water treatment systems, contact Netsol Water.