Heat conducting oil smoke residual heat recovery method

Abstract

The invention relates to a heat conducting oil circulating smoke residual heat recovery method which comprises the following steps of: carrying out heat exchange on high-temperature smoke of a convection chamber outlet of a heating furnace and a stream of heat conducting oil which is lower than the high-temperature smoke at temperature in a smoke-heat conducting oil heat exchanger and dischargingthe smoke with temperature reduction; exchanging heat with a working medium by using one stream of heat conducting oil with temperature rise as a heat source and leading the other stream to pass the side road; combining the heat conducting oil with temperature reduction with the heat conducting oil passing the side road or mixing the led heat conducting oil, the heat conducting oil with temperature reduction after carrying out heat exchange with the working medium and the heat conducting oil in the bypass and returning to the smoke-heat conducting oil heat exchanger to form a heat conducting oil cycle; and monitoring the temperature at a heat conducting oil inlet in the smoke-heat conducting oil heat exchanger and controlling the flow of the heat conducting oil at the bypass through usingtemperature as a parameter so that the temperature of the combined heat conducting oil is higher than the dew point temperature of the smoke. According to the method, dew point corrosion is prevented, great investment is saved, the heat of a smoke residual heat recovery system and other devices can be comprehensively utilized through an open type heat conducting oil cycle and the heat efficiency of the whole device is improved.

Description

technical field [0001] The invention relates to a flue gas waste heat utilization technology, in particular to a heat transfer oil flue gas waste heat recovery method which utilizes heat transfer oil as a heat medium and avoids dew point corrosion. Background technique [0002] The flue gas discharged from the heating furnace carries a large amount of heat, and the exhaust gas loss is the main part of the heat loss of the heating furnace. From the perspective of fuel consumption, every 10°C reduction in exhaust gas temperature can save about 1% of fuel. Therefore, flue gas waste heat recovery is an important means to save energy and improve furnace efficiency. At present, the technologies for reducing the exhaust gas temperature can be divided into two types: direct heat exchange and indirect heat exchange. Direct heat exchange includes introducing the low-temperature medium that needs to be heated into the end of the convection chamber, directly exchanging heat with the fl...

AI Technical Summary

Problems solved by technology

However, the outlet temperature of the convection chamber of many heating furnaces in oil refineries is usually 280-350 ° C. It is uneconomical to continue to increase the pressure of the water heat medium system, and maintain the water heat medium system at a lower pressure, and the temperature level will decrease accordingly. The loss of effective energy increases, and the waste heat of flue gas cannot be fully utilized

Images