Nantong Polyester New Material Wastewater Treatment Project

Project Background

A polyester new-material manufacturer in Nantong generates a large volume of high-concentration organic wastewater during production, characterized by high COD concentration and poor biodegradability. To meet environmental discharge requirements and achieve water resource reuse, the company commissioned us to design and construct a supporting wastewater treatment project.

Treatment Process

In view of the high COD and hard-to-degrade characteristics of polyester wastewater, this project adopts a combined process of "pretreatment + chemical dosing sedimentation + UASB + primary aerobic + sedimentation + secondary anoxic + secondary aerobic + MBR + RO", with the treated effluent reused for production:

• Pretreatment: bar screens intercept large suspended solids, and an equalization tank homogenizes flow and quality;
• Chemical Dosing Sedimentation: chemicals are dosed for coagulation and sedimentation to remove suspended solids and part of the organic matter;
• UASB Anaerobic Treatment: the upflow anaerobic sludge blanket decomposes macromolecular organic matter, greatly reducing COD and improving biodegradability;
• Primary Aerobic + Sedimentation: aerobic biochemical degradation of organic matter, followed by sedimentation for sludge-water separation;
• Secondary Anoxic + Secondary Aerobic: anoxic denitrification for nitrogen removal and aerobic nitrification, further removing organic matter and ammonia nitrogen;
• MBR Membrane Bioreactor: membrane separation replaces the secondary clarifier, delivering high-quality effluent with low suspended solids;
• RO Reverse Osmosis: advanced desalination for excellent effluent quality;
• Reuse: the treated effluent is reused for production, achieving zero liquid discharge and water resource recycling.

Project Results

After completion and commissioning, the project runs stably. The effluent, after advanced treatment by MBR + RO, is of excellent quality and is successfully reused for production, realizing wastewater resource utilization, effectively relieving the enterprise's environmental pressure and saving water costs.