Grundfos water treatment system

Grundfos Alldos’s Selcoperm system is used for disinfecting through the generation of hypochlorite solution using electrolysis, providing a good alternative to chlorine gas-based systems. While the system was designed predominately for the swimming pool market because it offered a safe way to produce sufficient disinfection, the technology is suitable for small to medium-sized town water supplies, especially in remote areas where there are limited chemical deliveries available.

Key components of the Selcoperm unit include an electrolysis system, storage tanks for the saturated salt solution and product solution, an exhaust fan for removing any hydrogen produced, and dosing pumps for the product solution. The system also has a measuring and control unit for chlorine dosing. The electrolysis system is supplied as a turnkey solution. Only the pipework for the water supply, the connections of the salt and product storage tanks and the exhaust pipe have to be installed. The size of the storage tanks depends on the capacity level of the system and the amount of disinfectant solution required.

The benefits of the electrolytic chlorination method include: common salt is the base material; only water, common salt and electricity is needed for the electrolysis — low operating costs; fresh hypochlorite is always on hand — the disinfectant solution does not dissociate like commercial hypochlorite solutions; lower formation of chlorate as a by-product and approved disinfection method complying with the DWI drinking water regulations — an alternative with fewer safety requirements to chlorine gas-based systems.

The system can handle peaks in demand because the disinfectant generated can be easily stored in buffer tanks for long periods of time. The benefits include: no transport, storage or handling of disinfectants; no formation of unwanted by-products; cost-effective use of common salt as a base material; precise on-site generation according to user requirements.