The waste heat recovery of flue gas can not only be used for heating or power generation to achieve energy-saving effect, but also can be beneficial to environmental protection and achieve dual effects of energy conservation and environmental protection. Hunan Gas fired hot blast stove In general, the important equipment of waste heat power generation is waste heat boiler, which mainly uses heat or combustible substances in waste gas, waste liquid and other working medium as heat source, and produces steam mainly for power generation. There are many ways to recover waste heat from flue gas of waste heat boiler. Generally, comprehensive utilization of waste heat is followed by direct utilization and indirect utilization. small-scale Gas fired hot blast stove factory Generally speaking, if heat sources are needed in the process, the waste heat utilization is mainly comprehensive utilization. First, the heat source is recovered and fed back to the process for reuse. If there is any surplus, it can be used for power generation or as the heat source for central heating; If there is no surplus, it will be directly used instead of being used for power generation; If the process does not need more heat sources, then indirect use, mainly power generation or public heating.

The existing industrial boiler flue gas waste heat recovery equipment mainly includes tubular heat exchanger and full heat pipe heat exchanger. Tube and tube heat exchanger can be composed of finned tube bundles. The advantage of finned tube is that it can withstand higher temperature, but has low heat transfer coefficient and large floor area. Hunan Gas fired hot blast stove The flue gas of industrial boilers contains sulfur and other acidic substances. In the low temperature zone (flue gas outlet section), the temperature may be lower than the dew point of the acidic substances. The acidic substances will dew on the pipe wall, corrode the shell of the fin tube. The fin tube heat exchanger has poor operating reliability and low service life. small-scale Gas fired hot blast stove factory The total heat pipe heat exchanger of boiler flue gas waste heat recovery equipment is composed of heat pipe bundles. Its shell is made of multi-layer composite materials. The heat pipe structure is complex, the cost is relatively expensive, the service life is short, and the steel consumption is large. It is difficult for users to accept it, and it is difficult to promote its application in production. The composite heat pipe heater not only takes into account the heat exchange effect, but also takes into account the economic affordability of the investors in production, which is particularly suitable for the current situation in China's industrial production.

The waste heat boiler for hazardous waste incineration is an important part of the hazardous waste rotary kiln incineration system. The heat source is the high-temperature waste gas containing strongly coking and cohesive ash after hazardous waste incineration. Hunan Gas fired hot blast stove Generally, this type of waste heat boiler adopts single flue or multi flue layout, and convection heating surface is arranged in the flue. During operation, strongly coking cohesive ash is easy to adhere to the convection heating surface, leading to flue blockage, affecting the safe and normal operation of the waste heat boiler. According to the characteristics of hazardous waste rotary kiln incineration system, a kind of waste heat boiler with special structure suitable for the system was developed, which successfully solved the problems of ash deposition, wear, air leakage, corrosion, etc. small-scale Gas fired hot blast stove factory The water circulation mode of the waste heat boiler is natural circulation. The working medium directly enters the drum, then is led out from the drum, flows into each membrane water wall through the downcomer, is heated here, then led back to the drum through the steam conduit, and is separated by the steam water separator, and then led out of the drum saturated steam with rated parameters.

As is known to all, the boiler using sensible heat of various waste gases and waste heat after waste incineration as heat source is called waste heat boiler, also called waste heat boiler. Therefore, the country advocates vigorously developing waste heat utilization, energy conservation and emission reduction, which plays a positive role in protecting energy and improving the quality of human living environment. Hunan Gas fired hot blast stove In the design of waste heat boiler, how to reasonably divide the temperature range is the basis for reasonably arranging the heating surface of waste heat boiler and making maximum use of waste heat. Under the condition of a given exhaust gas temperature at the inlet of the waste heat boiler, there are two requirements for the exhaust gas temperature. One is to limit the exhaust gas temperature, which is required to be within a reasonable range; The other is that the exhaust gas temperature is not limited, requiring greater use of waste heat. small-scale Gas fired hot blast stove factory In either case, for medium and low temperature waste heat utilization, the narrow point temperature difference directly affects the evaporation capacity of the waste heat boiler and the layout of the heating surface. Narrow point temperature difference, also known as node temperature difference, is a small temperature difference between evaporator outlet flue gas and heated saturated water vapor during heat exchange. With the change of narrow point temperature difference, the relative total heat exchange area, relative evaporation capacity and relative exhaust gas temperature of the waste heat boiler also change.