High purity water systems require a recirculation process to reduce the buildup of microorganisms in an RO or DI water storage tank. If there is not a loop design from the storage tank to the points of use and loop return to the tank, a recirculation system is a standard practice to insure the integrity of the water quality.
A distribution pump will continuously recirculate the RO/DI water back to the storage tank when the facility is not demanding water therefore the water in the tank is always being agitated. The return piping back to the tank will require a pressure regulating valve to adjust flow. A spray ball at the tank inlet is also helpful to thoroughly wash the inside walls of the tank. Since this pump runs continuously it is a good idea to have a float switch in the tank to shut the pump down if the tank is low of water.
In higher purity systems this recirc line would have DI tanks, a UV system followed by a 0.2 micron filter.
Flier’s engineering professionals have many years of experience designing high purity water systems and specifying proper equipment for any project.
