Air Preheater Boiler, High Temperature Exhaust Air

- Jan 25, 2018-

Main reason of air preheater boiler high temperature exhaust air

As the power station boiler air preheater generally has high exhaust temperature. The high exhaust gas temperature causes the boiler efficiency to decline. Therefore, the milling system dry output is insufficient. it is not economical for long-term operation. This is a common problem in the preheater industry.Through the power plant research can know the main reason of air preheater exhaust high temperature:

1. Serious dsign defects. Such as the actual boiler design parameters analysis, neglect on the preheater selection calculation and wrong choice of heat transfer plate and preheater models. These caused natural deficiency of the preheater. This is the main reason for the lack of preheater heat exchange capacity. 

2. Poor manufacturing quality. Preheater internal heat transfer components have strict size requirements. Geometrically small differences will also result in a huge difference in the ability of the preheater to exchange heat. Therefore, the variation of the thickness of the heat transfer element and the difference in the internal combined dimensions between the elements when manufactoring will greatly affect the preheater heat exchange capacity. This is also the main reason for the lack of preheater heat exchange capacity.

3. Large air leakage of milling system. The large air leakage of milling system results in  reducing intake of organized air into the preheater and it eventually results in high preheater exhaust temperature.

4. Increased air leakage at the hearth. Its principle is the same with the milling system. They all reduce the intake of organized air into the preheater. 

5. Other reasons.


After analyzing the specific reasons, do a cost-effective transformation. If the preheater is inherently deficient, it needs to be replaced. Therefore, the attention to the design of preheater is a powerful guarantee of its performance.