XINLI BOILER

Biomass boiler fuel moisture can not be greater than 60%

17 Feb, 2022

　　Biomass boilers include biomass-fired steam boilers and biomass-fired hot water boilers. With the arrival of the winter heating season, the demand for biomass-fired steam boilers for heating gradually increases. However, when we use it, if the fuel moisture is too large and the calorific value in the boiler is too low, it will seriously affect the normal combustion, resulting in a series of problems such as furnace deflagration, excessive carbon content, and reduced boiler efficiency.

　　At present, most biomass boilers cannot adapt to the incoming fuel with moisture greater than 60%. Therefore, if the fuel with too high water content is used, the boiler will not be able to burn properly. It is mainly manifested in the following two aspects:

　　First of all, the biomass boiler is under positive pressure during combustion, and the carbon content of the ash is high. Once the calorific value of biomass fuel is lower than about 7000kj and the moisture content is greater than 50%, water vapor will be formed in the boiler to release heat absorption, and then the combustion will release heat, which will lead to frequent positive pressure in the boiler. Since a large amount of water vapor in the boiler reduces the furnace temperature, the added oxygen is surrounded by water vapor to form a barrier, so that it is difficult to fully mix with the flame, so that the combustion is oxygen-deficient.

　　The second is the problem of fly ash in the tail flue. When a large amount of incompletely combusted fly ash enters the tail flue, causing the ash to be placed in the pre-dust collector and ash storehouse, the hot fly ash will have obvious sparks when it encounters the air, which is easy to burn out the filter bag and accelerate Wear of the induced draft fan impeller.