Wastewater Treatment Plant Disinfection Project

Find a safe, controllable disinfection solution for a large municipal wastewater plant.

Chaoyang Urban Wastewater Treatment Plant in Shantou, Guangdong Province, is responsible for the centralized treatment of domestic sewage and part of the industrial wastewater from Chaoyang urban area and surrounding regions, with a daily treatment capacity of 150,000 tons. As local environmental discharge standards became stricter, the stability and safety of effluent disinfection became a critical part of the plant's compliance operation. Traditional liquid chlorine disinfection carries transport, storage, and leakage risks — and safety management pressure is particularly high in densely populated urban environments. Purchased sodium hypochlorite, meanwhile, faces rapid available chlorine decay and procurement and transport costs that scale with volume. The plant needed a disinfection system that could match a 150,000 tons/day treatment capacity, with controllable safety risks and predictable operating costs.

Two 45 kg/h Sodium Hypochlorite Generators — On-site Generation, On-demand Adjustment

The project was equipped with two sodium hypochlorite generators with a single-unit capacity of 45 kg/h, producing disinfectant on-site through salt water electrolysis. The two systems can operate in parallel to meet peak disinfection demand, or flexibly adjust dosing based on changes in water volume and quality — adapting to the significant influent fluctuations typical of wastewater treatment plants. The on-site generation model means the plant only needs to store salt as a raw material. Disinfectant is generated and used immediately, with stable available chlorine concentration — avoiding the decay problem of purchased sodium hypochlorite during storage, while also eliminating the major safety risks of liquid chlorine transport and storage.

Stable Compliance and Upgraded Safety Management for Urban Wastewater Plant Effluent Disinfection

The system was commissioned in 2019. The on-site sodium hypochlorite generation model helped the plant achieve stable compliant discharge in effluent disinfection, effectively controlling hygiene indicators such as fecal coliforms. Because the disinfectant is generated and used immediately without the need for large-scale storage, the plant's safety management pressure in an urban environment was significantly reduced. This project provides a reference engineering practice for disinfection system selection at large municipal wastewater treatment plants in eastern Guangdong, and validates the reliability and cost-effectiveness of sodium hypochlorite generators in large-scale wastewater treatment applications.

Client Testimonial

"Our plant treats 150,000 tons per day and is located in Chaoyang urban area, surrounded by a dense population. The safety management pressure from liquid chlorine and purchased sodium hypochlorite has always been high. After switching to two 45 kg/h sodium hypochlorite generators in 2019, the safety risks in our disinfection process dropped significantly — we only need to store salt on-site, and the disinfectant is generated and used immediately without large-scale storage or worrying about available chlorine decay affecting disinfection performance. After several years of operation, effluent disinfection indicators have remained stable and compliant, and management has become much easier. For a large urban wastewater plant like ours, this was the right choice."

— Technical Manager, Chaoyang Urban Wastewater Treatment Plant, Shantou, Guangdong