Island Water Disinfection Project (Stainless Steel)

Build a safe, self-reliant disinfection system for decentralized island water supply nodes.

The Zhoushan Archipelago is located in the East China Sea, with scattered islands and inconvenient transportation. Some water plants and supply stations have long faced practical constraints such as high transport costs and poor supply stability for purchased disinfectants. The 7 water supply nodes covered by this project are distributed across different islands, with a combined daily treatment capacity of 7,000 tons, responsible for ensuring drinking water safety for island residents. For these sites, liquid chlorine transport carries high safety risk management pressure, while purchased sodium hypochlorite — due to rapid available chlorine decay and tanker transport being heavily affected by weather and sea conditions — struggles to form a stable supply guarantee. The water plants needed a disinfection solution that does not depend on external chemical supply chains, can operate on-site at each island node, and is safe and controllable.

Seven 300 g/h Sodium Hypochlorite Generators — Distributed "One Island, One Station" Configuration

The project adopted 7 sodium hypochlorite generators with a single-unit capacity of 300 g/h, deployed separately at each island water supply station, producing disinfectant on-site through salt water electrolysis. This "one island, one station" configuration means each node only needs to store salt as a raw material, completely eliminating dependence on tanker transport and purchased disinfectant supply chains. The system operates automatically and can adjust dosing based on changes in water volume and quality at each station — adapting to the reality of limited operating personnel and relatively weak technical capabilities at island water plants. The on-site generated sodium hypochlorite is produced and used immediately, with stable available chlorine concentration, avoiding the decay problem of purchased solution during storage and cross-sea transport.

A Self-reliant Disinfection Practice for Decentralized Island Water Supply

The system was commissioned in 2024. The distributed deployment of 7 units enabled each island water supply station to achieve on-site production and on-site use of disinfectant, fundamentally solving the problems of difficult transport, difficult storage, and unstable supply of purchased disinfectants in the island environment. Finished water residual chlorine remains stable and compliant, providing sustainable operational assurance for drinking water safety at decentralized water supply nodes in the Zhoushan Archipelago. This project validates the scalable applicability of compact sodium hypochlorite generators in multi-node, decentralized island water supply scenarios, providing a replicable engineering model for water supply disinfection under similar geographical conditions.