Waste Water Treatment is the process of removing physical, chemical and biological contaminants from waste water, household & commercial sewage, to produce environmentally safe effluent and solid waste (sludge/ fertilizer) that is suitable for discharge to the surrounding environment or an intended reuse application like irrigation, horticulture & water features. With a water protection mindset, the aim is to prevent water pollution from raw sewage discharge, reduction in water demand, reusability of treated water, reusability of sludge as fertilizer, water sustainability & harmony with nature.

A typical Waste Water Treatment plant with MBBR technology will have the following process: -

The waste water after passing through screen chamber and oil and grease trap will be collected in collection cum equalization tank (EQT). Air shall be provided in this tank to keep the suspended solids in suspension & to avoid any potential odour problem.

From this tank, waste water will be pumped to anoxic tank with agitator for the denitrification process. After anoxic tank waste water will go to MBBR tank for biological treatment. The MBBR tanks consists of PVC fill media, which shall facilitate the attached growth of microorganism. The aerobic environment in the aeration tank shall be achieved by use of fine bubble diffused aeration, which also serves to maintain the liquor in a completely mixed regime. The mixed liquor from the MBBR tank overflows into a hopper bottom of tube settler tank (TS). Where the sludge settles down and clears water overflows into chlorine contact tank.

The treated water from the tube settler tank (TS) shall be collected in the chlorine contact tank. Chlorine dosing is done for disinfection. This tank will also act as storing tank for filter feed pumps.

Treated water from filter feed tank/chlorine contact tank will be pumped to multigrade filters (MGF) for removal of suspended solids and turbidity. This filter shall be provided with sand and anthracite as filtering media. After (MGF) the treated water will be passed through the activated carbon filter (ACF) for further polishing of water. After filtration, treated water shall be stored in treated water tank. This treated water is fit for reuse in irrigation/horticulture.

The sludge settled in the tube settler tank will be transferred to the sludge drying beds where it can be used as fertilizer for green areas, whereas the surplus activated sludge will be recirculated to the anoxic tank.

Zehn Consultants have global proficiency in the following Waste Water Treatment technologies:

• Moving bed bio reactor technology (MBBR)
• Membrane bioreactor (MBR)
• Sequencing batch reactor technology (SBR)