Characteristics of Heat Pipe Preheaters for Steam Boilers
Characteristics of Heat Pipe Preheaters for Steam Boilers
The purpose of a heat pipe preheater is to preheat boilers, combustion air, etc. Its characteristics are as follows:
(1) Both cold and hot gases flow outside the heat pipe, meaning that heat exchange between cold potential fluids occurs outside the pipe. Therefore, fins can be added to enhance heat transfer, resulting in a compact volume and high heat transfer efficiency. After retrofitting an industrial boiler with a heat pipe air preheater, the boiler efficiency can be improved by approximately 10%.
(2) The density of the fins on both sides of the heat pipe affects the temperature of the working liquid steam inside the pipe. Therefore, by adjusting the number of fins on a single heat pipe, the steam temperature can be maintained above the dew point temperature of the flue gas, which can avoid low-temperature corrosion and ash blockage of the pipe wall.
(3) The heat pipe is evacuated internally, and the working fluid is prone to boiling and evaporation, resulting in a rapid start of the heat pipe.
(4) The hot side (flue gas side) and cold side (air side) of the heat pipe are separated by partitions, and there is a reliable seal between the heat pipe and the partition, with a leakage coefficient close to zero.
(5) The heat pipe air preheater is a stationary equipment, with each heat pipe being an independent component. It has a simple structure, easy replacement, almost no mechanical failure, reliable operation, and a service life of over 8 years.