Whether it is power generation, production or mining, cost of fuel constitutes a significant portion of the cost of the resultant product. There is also normal wastage in the form of effluents and releases associated with these processes. With the price of raw materials like diesel, natural gas and coal that are used as fuel for such processes touching sky, it is but apparent that there is a need to efficiently use the existing resources. This is where devices called economizers can be real game changers. They not only economize the processes but also reduce the stress on rare non-renewable resources used in production.
How do Economizers work?
Economizers are tubular heat transfer surfaces that basically capture the escaping heat and re-using it, thereby increasing the efficiency of the operations. Now, visualize a boiler system in which water is heated in the boiler to convert it to steam. After the cycle the hot exhaust gas escapes in the atmosphere through exhaust funnel, but what economizer does is, it captures a part of the heat of these exhaust gases and uses it to pre-heat the water entering into the boiler. This reduces the burden on the boiler as the part of its work is already done by the economizer. This process increases the efficiency of operations significantly and also results in cost savings in terms of fuel consumption and elongating the life of main equipment, in this case boiler.
Types of Economizers
There are four types of heat economizers and Advanced Industrial Components Inc offers them all , they are:
Gilled Tube Economizers are made using cast iron fins that give high efficiency. They are particularly suited for process industries, chemical plants and waste water boilers where heavy amounts of intoxicated flue gas is released.
Horizontal Finned Tube Economizer is a seamless steel tube seal-welded with horizontal fins to make a complete assembly for heat transfer. Special care is taken so that fins have a proper contact with tubes for seamless heat transfer. These economizers are used in Thermal power and captive power plants.
Round Gilled Tube economizer is fabricated with square and round fins that are welded on steel tubes. Special care is taken during fabrication to ensure proper contact of fins with tubes for seamless heat transfer.
Coiled Tube Type economizers are compact and thus occupy a small space. They are considered ideal for use in thermal power plants and are more efficient in recovering heat from gases as compared to gilled tube economizers.
Apart from these four categories, one can also divide economizers into two categories based on how much they contribute to boiler efficiency- One, non Condensing economizers and two, condensing economizer. The former is widely used in Thermal power plants and is located near the exit region of the boiler. It captures the heat of exiting flue gas and transfers it to steam boiler feed water. It also limits the cooling capacity of Flue gas, thus increasing the overall efficiency of the boiler. Condensing economizer is used in natural gas Thermal power plant. It recaptures heat from Flue gas as well as latent heat by condensing water vapors in the flue gas.