Abstract: Taking one 600-MW combined power, water and heat generation unit for example, the characteristics of the water treatment process including boiler make-up water, condensate water and boiler feed water are introduced. According to the problems such as the over-long desalination regeneration cycle, the high condensed water dissolved oxygen content and water-vapor system containing hydrazine, related technical innovations are carried out as follows. First, since the raw water of the water treatment system is the condensate generated from the seawater desalination system, its quality is equivalent to the desalting water. Therefore, it can be desalinated by a bypass system. Second, the way of replenishment is modified in which the positions of the replenishment and the pump seal return water are changed from the original condenser hot well to the condenser throat with the atomizing nozzle being added at the throat. Third, the water treatment conditions are changed, i.e., changing the feed water treatment method from AVT(R) to AVT(O) for subcritical boilers and from AVT(R) to OT for supercritical boilers with the hydrazine treatment stopped in the combined power, water and heat generation unit. After taking the above optimization procedures, the problems of the original system are solved.

Key words: combined power, water and heat generation unit, water treatment, makeup water, feedwater, condensate, condenser