feedwatersystem

Feedwater system refers to the set of equipment and piping that supplies boiler feedwater to a steam-generating unit. In most power plants, the system recovers condensate from turbine exhaust, treats and preheats it, and delivers it to the boiler at the required pressure to sustain steam production and maintain proper boiler water level.

Key components include the condensate return system (condensate receiver or hotwell and piping), condensate pumps, a deaerator to remove dissolved gases, feedwater pumps (one or more with redundancy), feedwater heaters (including both low- and high-pressure units), and an economizer that preheats water using exhaust heat. Control valves, level and pressure instrumentation, and appropriate safety devices are also integral to the system.

Operation involves returning condensate to the plant, pumping it to the deaerator where dissolved oxygen and other gases are removed, and then preheating the water through feedwater heaters and an economizer. The preheated feedwater is then pumped into the boiler at the required pressure and temperature to sustain efficient steam generation. Water chemistry control, often including oxygen scavengers and pH adjusters, is used to minimize corrosion and scaling.

Design and maintenance considerations focus on reliability, corrosion control, and thermal integrity. Redundancy in pumps and heaters, proper materials selection for high-temperature service, regular inspection of piping and valves, and monitoring of water chemistry are essential to ensure safe and efficient boiler operation. The feedwater system is a key interface between condensate recovery and steam production.