What are the functions of open and closed circulating water pumps in thermal power plants?

It is distinguished according to the water quality and the purpose is to provide the corresponding cooling water to cool the system oil cooler, machine seal, etc. Free water is directly extracted from the circulating water inlet jellyfish pipe and is transported to the main engine, small machine and other oil coolers using an open pump. Water quality does not need to be very high. circulate the water to the jellyfish pipe, and the incoming water is filtered by the water filter to remove impurities. The closed water is extracted from the closed water tank in the form of demineralized water. Generally, systems that supply electric pumps, feedwater pump seal cooling water, condensate pump seal water, and generator hydrogen coolers require good enclosed water quality that circulates automatically and heat is exchanged with the watercirculating free water through the chiller.