Boiler economizer can reduce the flue gas temperature, recovery of flue gas heat, improve boiler thermal efficiency, save fuel. The temperature of the superheater is about 700 ℃, and even if the convection tube bundle is arranged after the superheater, the temperature of the furnace is still 250 ~ 350 ℃ because of the saturated temperature of the boiler water temperature. Contains a lot of heat. In the superheater or convection tube installed after the economizer, you can effectively reduce the flue gas temperature, recycling a lot of heat, save a lot of fuel, because the early boilers are usually coal as fuel, so called economizer.
Boiler economizer installed, into the drum of the feed water temperature greatly improved. For boiling economizers, the feedwater temperature into the drum is the saturated temperature at the drum pressure. For non-boiling economizers, the feedwater temperature of the drum is not reached but also close to the saturation temperature. Therefore, after the water is heated by the economizer, due to the water temperature is equal to or close to the saturated temperature under the drum pressure, can reduce the thermal stress caused by the temperature difference before the ignition of the boiler has been on the water level to the lowest water level, but the ignition , The water level rises due to the increase in the temperature of the furnace. With the further increase in the temperature of the furnace water, water vapor gradually generated steam, boiler water level to rise further.