Segregated Wastewater Treatment and Recycle Solution for a 6.8 GW Solar PV Cell Line Manufacturing Facility
| Challenge: | The key challenge was to design a robust, segregated wastewater treatment system that efficiently handles variable loads while maximizing water recovery and reuse. |
| Solution: | To address these challenges, a segregated wastewater treatment strategy was implemented, consisting of three independent treatment schemes designed around wastewater strength and composition. |
| Customer Benefit: | Aquatech delivered an efficient and reliable wastewater management system through proper segregation and targeted treatment of dilute, concentrated, and ammonia-nitrogen streams. |
India’s first and largest vertically integrated solar PV cell and module manufacturing facility has an existing capacity of 1.5 GW, expanding to 3.5 GW, ranking it among the top 15 global solar manufacturers. It uses advanced technologies, best-in-class equipment, and global reliability standards to support India’s clean energy goals. The current project includes a 6.8 GW cell line capacity (1.7 GW MSEL / 5.1 GW ANIL), strengthening the expanding solar ecosystem.
Challenge
Solar PV cell manufacturing generates complex wastewater from multiple processes, including chemical etching, diffusion, cleaning, and metallization, containing high levels of fluoride, ammonia, acids, alkalis, metals, and TDS. The key challenge was to design a robust, segregated wastewater treatment system that efficiently handles variable loads while maximizing water recovery and reuse.
Solutions
To address these challenges, a segregated wastewater treatment strategy was implemented, consisting of three independent treatment schemes designed around wastewater strength and composition.
Dilute Wastewater Treatment Scheme: Dilute wastewater is collected in a regulation tank and treated through staged physico-chemical and membrane processes, including fluoride, silica, and hardness removal to protect membranes. The stream is then polished by MMF and UF, treated in a two-pass RO system for high recovery and reuse, with final RO reject subjected to Fenton oxidation.The RO permeate is reused for process applications within the plant.
Concentrated Wastewater Scheme:The high-strength wastewater stream is treated in an ammonia stripper, followed by equalization with fenton outlet, concentrated acid and other streams and two-stage fluoride removal using primary and secondary HRSCC units. The treated effluent is then integrated with the ammonia stream for optimized downstream treatment and chemical efficiency.
Ammonia-Nitrogen Wastewater Treatment Scheme: The ammonia-nitrogen-rich stream is stripped, blended with concentrated acid, and treated for fluoride removal before undergoing biological treatment in an anoxic/aeration tank for effective nitrogen removal. This is followed by a secondary clarifier for solids separation, after which the clarified effluent is disposed of in compliance with applicable statutory and environmental regulations.
Fig 1. Dilute Stream
Fig 2. Concentrated Stream
Fig 3. Abatement Stream
Results
The project delivers an efficient and reliable wastewater management system through proper segregation and targeted treatment of dilute, concentrated, and ammonia-nitrogen streams. It ensures high water recovery and reuse with optimized energy and chemical consumption, while effectively handling fluoride, ammonia, silica, hardness, and high-TDS effluents- supporting sustainable operations aligned with client’s clean energy and ESG commitments.