The function of the Economizer in the Boiler is to heat the Boiler filler water by utilizing the heat from the combustion gases inside the Boiler. As the temperature of Boiler filler water rises, Boiler Efficiency will also increase.
The remaining combustion gas fuel in the Boiler still has a high enough temperature. By passing the combustion gases through the Economizer pipes, there will be a transfer of heat which will be absorbed by the Economizer pipes and the heat is transmitted into the Boiler fill water contained in the Economizer pipes.
Economizer Functions on Boiler Efficiency
With the increasing temperature coming out of the Economizer, the water temperature in the Boiler drum will also be high. If the water in the Boiler drum is already high then less heat will be needed to convert the water into steam in accordance with the planned amount. The need for fewer calories will certainly have an impact with reduced use of fuel. Increased Efficiency in a Boiler, it will make the company’s expenses will also be more economical in terms of reducing the purchase of Boiler fuel.
Economizer is one of the important components of Boilers located on the inside of Boilers, precisely between Superheater and Air Heater. Usually Economizer in Boiler consists of several levels, and between Economiser level one is separated by a room that contains a Soot Blower to clean the Economizer pipes from dirt or dust that sticks to the outer Econpmizer pipes.
To connect Economiser level one with another level, Economiser is usually connected by a Header that functions as a water collector and also to facilitate maintenance of the Economiser by the maintenance in case of damage to the Economist pipes. Some Manholes are also found in the Boiler wall between the Economizer one and Lainya stations which function as human inlets to check the state of the Economizer pipes during Bout Shutdown.
Water flow in the Economizer
Boiler fill water flow comes from BFP (Boiler Feed Pump) and passes the Economizer before heading to the Boiler Drum / Steam Drum Boiler. In the Economizer the temperature of the boiler fill water at the outlet / outlet of the Economizer will be higher than the temperature of the incoming water at the entry / inlet of the Economiser. This happens because the temperature between the Boiler filler water contained in the Economist pipes is lower than the temperature of the Boiler exhaust gas which is outside the Economizer pipes, so that there will be heat transfer from the combustion buag gas to the Boiler filler water.
Boiler flue gas temperature will drop after passing the Economizer and vice versa Water temperature of the Boiler Drum filler will increase after passing the Economizer.
The temperature of water entering the Economizer depends on the temperature of the water from the Deaerator Tank and the HPH (High Pressure Heater). If the temperature of the Boiler filler water from Deaerator is high and the HPH is also operated, the temperature of the water entering the Economizer will also be high. Usually when Turbine Generator load is high and Turbine Extraction vapors are abundant, the temperature of the Deaerator and HPH Outlet will also be high and of course the temperature of the Boiler fill water that will enter the Economiser will also be high.
Alian Gas Dispose of the Economizer
The flue combustion gas will pass through the Economizer outside the Economizer pipe. Combustion in the Boiler besides producing heat will also produce exhaust gases which will be discharged into the atmosphere. The flow of combustion exhaust gas in the combustion chamber will pass through Boiler Components such as Superheater, Economizer, Air Heater, ESP, FGD, New Chimney to the Atmosphere.
Boiler combustion residual gas will pass through the superhaeater and be forwarded to the new Economizer outlet section to the Inlet Economizer section before heading to the Air Heater.