Analysis Of External Procedure And Assessment Of Retrofit Scheme Of Heat Recovery Area In Xiahuayuan Power Plant's HG-670/140-9's Boiler

ABSTRACTOur county is a big coal-producing country. The resource of coal is abundant. And the quality of coal varies in a wide range. About half of the coal used in large capacity unit belongs to coal easy to stick ash. The major coal producing area is rich of low ash fusion point coal. So mixed coal combustion result in easy change of combusting coal of the boiler, and the ash percent increasing, heat value decreasing. The drop of combusting coal grade also pick up the problem of wear, ash sticking and eroding, which reflect on the life-span decline of heat exchanger surface of boiler, and tube failure frequently occurring. So the wear, ash sticking and eroding are the outstanding problems of heat recovery area of boiler, and need to solve in soon.On the basis of checking thermal calculation over again, assessment and design of retrofit scheme of heat recovery area is done in this paper according to the change of burning coal character of Xiahuayuan power plant's HG-670/140-9 boiler. We figure that fin tube economizer is the top-priority form in new unit designing or reconstructing of aged set. Heat pipe air preheater has wide foreground in replacing low temperature air preheater of power plant, so it is worth popularizing.