ASME Carbon Steel High Safety Level Boiler Air Preheater for Power Station Maintenance

General Introduction: Air Preheater

Air preheater is a kind of preheating equipment that improves the heat exchange performance of steam boiler and reduces heat loss. The function of the air preheater is to conduct the heat carried in the flue gas discharged from the flue at the tail of the boiler into the air which have yet to enter the boiler through the sheet, and preheat the air to a certain temperature. The air preheater can use the heat energy carried by the flue gas at the boiler outlet to preheat the boiler combustion air or other drying purposes.

Working Principle

Taking the rotary air preheater as an example to illustrate the principle of air preheater, it will rotate slowly during operation, the flue gas will enter the flue gas side of the air preheater and then be discharged, and the heat carried in the flue gas will be absorbed by the heat sink in the air preheater, and then the air preheater rotates slowly, the heat sink moves to the air side, and then the heat is transferred to the air before entering the boiler.

The application of air preheater in boiler is mostly three-compartment type, with fire alarm system, gap adjustment system and frequency conversion control system. Air preheaters are easy to use, simple to operate, safe to operate, and can improve the heat exchange performance of the boiler system, so it is very commonly used in flue gas boiler systems.

Details

The main heat transfer component of tubular air preheater is thin-walled steel tube. The tubular air preheaters are mostly cubic. The steel tubes are arranged vertically and staggered with each other. Both ends are welded on the upper and lower tube sheets.The tubular air preheater is equipped with an intermediate tube sheet in the tube box. The flue gas passes through the preheater up and down the pipe, while the air passes through the preheater horizontally to complete heat transfer.

Tubular air preheater is widely used in power station boilers and industrial boilers because of its advantages of good sealing, high heat transfer efficiency, easy manufacturing and processing. The shortcomings of tubular air preheater are large volume, easy ash plugging of steel tube content, difficult cleaning and easy wear and tear at flue gas inlet.