DJB Sets Up Waste Water Treatment Plant with Latest Technology

DJB Commissions State-Of-The-Art WWTP at Chilla

The Delhi Jal Board, in its effort to provide better sewage treatment facility to the city,has commissioned a state-of-the-art Waste Water Treatment Plant (WWTP) at Chilla. Thetechnology used in the plant, the Improvised Sequential Batch Reactors (ISBR) technology, ismore economical and delivers better output as compared to other technologies. The Dual Membrane Dome and generation of Hydropower are two important and uniquecharacteristics of the ISBR technology and is first-of-its-kind in the world. The patent for thetechnology is pending. This WWTP is located at Chilla in East Delhi, which is a densely populated area. The useof the ISBR Technology makes it possible to set up allows the plant in a small area. Hence, DJBhas constructed this 9 MGD plant on a very small foot print, i.e., about 40% of the size of aconventional plant, along the Shahdara Drain no. 1 on a DBO (Design-Build-Operate) basis. Earlier, the sewage was treated using techniques such as (1) Activated Sludge Process i.e.ASP (2) Up-flow Anaerobic Sludge Blanket i.e. UASB (3) Sequentional Batch Reactor i.e. SBR.Typically, WWTPs based on conventional ASP require large areas and the WWTPs using theUASB technique require large areas and do not deliver consistent performance, while SBR basedWWTPs consume very high electric power. Other factors such as the intermittent supply ofelectricity also deter the smooth functioning of WWTPs. As a result of this, the treated effluentof poor quality flows into the River. It is expected that with the introduction of the ISBR technology the sewage will be treatedwith better efficiency and more economically. The technology uses both anaerobic and aerobicprocesses to treat sewage. The Combi-treat unit generates biogas by treating the sewageanaerobically, which then reduces the organic load to be handled by further treatment in theISBR basins. The biogas that is generated is stored under flat-roofed Combi-treat unit which ensuresproper sealing of the reactor to avoid any leakage through it, which is generally observed atdome like digesters. The Membrane Dome pushes out the gas but remains unharmed due to thecorrosive gases within the digester which is not possible with conventional metal-roofeddigesters. The ISBR provides aerobic treatment and has improvements over the SBR sewage treatment technology that enables it to create a suitable condition for the generation ofhydropower while maintaining the outlet quality at par with the SBR technology. It is pertinentto note that this is the only technology in the world which can generate hydropower throughsewage even on a flat terrain. In addition, power is also produced from methane and biogaswhich keeps the environment clean and healthy. The power generation within the plant will reduce dependency on power grids, as well. The Combitreat-ISBR requires minimal land area and the plant premises are veryhygienic and are, therefore, suitable for densely populated areas such as Delhi. When it comes tothe outlet parameters, Combi-treat-ISBR is the frontrunner. It consistently delivers BOD <10mg/l, TSS < 10mg/l, high nitrate and phosphorus removal. After witnessing the 3 year performance of the first WWTP based on this technology of 30MLD capacity at Pune, Delhi Jal Board scrutinized the Technology through independent expertsfrom IIT Kanpur. Based on the findings of IIT Kanpur experts, DJB decided to employ the use ofISBR technology for its 9 MGD capacity WWTP at Chilla. Currently, the plant is undergoing trial runs and is under the process stabilization phase.Since the treated effluent will be of good quality, an improvement in the water quality of theRiver is also expected once the treated sewage is released into it.With the use of this technologyand the resultant energy efficiency of the plant, DJB expects a positive impact on its financialstatus as well.

Source: Delhi Jal Board

Media

Taxonomy

• Sludge Separation
• Waste Water Treatments