In response to acute water stress and frequent droughts in Gujarat, Reliance Industries entrusted WABAG with the development of India’s largest recycling facility for PTA effluent at its Dahej complex. The project, executed on a Design-Build-Operate (DBO) basis, integrates anaerobic and aerobic biological treatment with ultrafiltration and reverse osmosis to reclaim wastewater from PTA and PET operations. Commissioned in phases beginning 2014 and fully operational since 2015, the plant exemplifies industrial circularity and resource efficiency by reclaiming treated wastewater for process use and harnessing biogas for energy recovery.

Project Highlights:

• Scope:
  End-to-end DBO execution involving design, engineering, construction, installation, testing, and commissioning of a multi-module, high-efficiency effluent treatment and water reclamation system, with WABAG subsequently assuming a 36-month O&M responsibility.

• Treatment Process:
  • Anaerobic and Aerobic Treatment: UASB reactors and MARAPUR-MBR® system
  • Advanced Tertiary Treatment: Ultrafiltration and Reverse Osmosis
  • Biogas Recovery & Reuse: Gas holders, gas dryers, and CHP units for plant utilities
  • Sludge Management: Belt filter press, sludge drying, and nutrient recovery

• Impact:
  The plant recycles up to 43,200 m³/day of industrial wastewater, significantly reducing the complex’s reliance on external water sources. It generates 63,000 m³/day of biogas, meeting 40% of the site’s heating needs and exemplifying energy-efficient operations. By treating and reusing challenging industrial effluents, this project supports water sustainability in one of India’s most water-scarce region.