Worli wastewater treatment plant (India)

The Worli wastewater treatment plant aims to

• restore the quality of the ArabianSea with a treated effluent of quality compliant with the latest local standards [NGT, National Green Tribunal] in terms of pollution control.
• reuse 50% of the treated water for municipal and industrial non-potable use with water quality compliant with CPHEE0 (Central Public Health & Environmental Engineering Organisation) standards.
• achieve class A biosolids quality [USEPA, United State Environnemental Protection Agency) with a dry matter content of 25% allowing for reuse in soils without health risk.

key figures

• treatment capacity of 500,000 m³/d
• area 8,5 hectares
• reuse by 50% of the treated water of the plant, i.e. 250,000 m³/d
• production up to 39 GWh of green electrical energy per year from biogas
• 75% self-sufficient facility
• 31,800 t CO₂ per year avoided

treatment line

• primary physico-chemical decantation Densadeg® integrating a sludge pretreatment by thickening in the same structure.
• secondary treatment using the Ultrafor® process that integrates both a biological treatment by activated sludge and a clarification by immersed ultrafiltration membranes.
• mechanical sludge thickening Drainis® GDE.
• 2-phase methanization with upstream biological hydrolysis Digelis® BHA with advanced heat recovery that allows the sludge to be sanitized while moving towards energy self-sufficiency.