Question 58Steam Plants - QMED

The correct answer is A) Main condensate pump. The main condensate pump operates at a constant speed and delivers water to the deaerating feed tank at a nearly constant pressure. This is because the main condensate pump is responsible for drawing condensate from the main condenser and delivering it to the deaerating feed tank, which is a critical function in the boiler water supply system. The constant speed and pressure ensure a reliable and consistent flow of water to the deaerating feed tank, which is necessary for the proper operation of the boiler. The other options, such as the main feed booster pump, main circulating pump, and main feed pump, are not the correct answer as they may operate at variable speeds or deliver water at varying pressures, depending on the system's demands.