Situation
In this solar industry factory, the process of cutting silicon wafers generates wastewater that contains not only Ionic but also large amount of complexed nickel，hard biodegradable organic matter and inorganic salts. Due to the high water costs, the factory has opted for a Zero Liquid Discharge (ZLD）solution, which would recycle 86% of the wastewater back into the production line.
Core Solution
Step 1: Removal of silicon powder suspended solids (SS)
Step 2: The hydrolytic acidification process enhances biodegradability of the wastewater.
Step 2: Use of aerobic microorganisms to degrade organic matter.
Step 3: Removal of silica and hardness in water through a high-density sedimentation tank.
Step 4: Concentration of wastewater using membranes such as UF and RO, with the permeate being reused in the production line.
Step 5: The concentrated wastewater enters evaporation and crystallization, and the resulting solids are transported offsite, purified water reused to producing line.
Client: A solar industry factory cutting silicon wafers in Northwest China
Treatment Capacity: 3600 m3/day