The biomass boilers used in modern industry not only solve the problem of environmental pollution caused by traditional boilers, but also reduce the use of coal and other resources. However, in the combustion products of biomass boilers, we sometimes find that there are a lot of combustibles, and slag blackening, as well as combustion gases containing a lot of carbon monoxide combustible components. Such phenomena are typical incomplete combustion problems.
At present, the main factors leading to incomplete combustion of fuel in biomass boilers are: insufficient temperature in the furnace, usually below 600 C, it is impossible to establish a good combustion structure; the air supply can not meet the needs of complete combustion of combustible components in fuel; the air supply is sufficient, but the combustion disorder is caused by poor mixing contact; When the moisture content of the base fuel is more than 45%, it is difficult to ensure normal combustion; the fuel particles are too large to facilitate combustion reaction; the reaction time of combustion is insufficient or the vibration amplitude of grate is too large, the interval is too short, and the combustion time is insufficient; the ash content is too large, and the coke particles are wrapped up, which slows down the combustion speed; the feed is too much and the furnace is too slow. The material layer on the grate is too thick to be benignly mixed with gas and solid, and there is little feed or insufficient heat storage capacity of the grate material layer.
Q:Reasons for Incomplete Combustion of Biomass Boiler Fuel
A:The combustion products of biomass boilers contain a lot of combustibles, and the ash and slag are blackened. Sometimes the raw material is discharged. The combustion gas contains a large amount of combustible carbon monoxide.
The factors causing incomplete combustion of boiler fuel are as follows:
(1) Furnace temperature is insufficient, under normal circumstances, it is impossible to establish a good combustion structure when the temperature is lower than 600 C.
(2) The air supply can not meet the need of complete combustion of combustible components in fuel.
(3) The air supply is sufficient, and the combustion is disordered due to poor mixing contact.
(4) Abnormal accidents occurred.
(5) The moisture content of the base fuel is too high to ensure the normal combustion of the fuel with more than 45% moisture.
(6) Fuel particles are too large to facilitate combustion reaction.
(7) The reaction time of combustion is not enough, the vibration range of grate is too large, the interval is too short, and the combustion time is short.
(8) The ash content is too large and coke particles are wrapped in the ash, which makes the combustion speed slow.
(9) Too much feed, too thick charge layer on grate, gas solid can not be benignly mixed.
(10) Fewer feeds or less heat storage capacity of thin bed of grate.
Q:Reasons for incomplete combustion of fuel in straw boilers:
A:Straw boilers are also a kind of biomass boilers. The fuel of straw boilers is biomass pellet fuel, which does not produce polluting gas and dust when burning. It not only solves the problem of environmental pollution caused by traditional boilers, but also reduces the use of coal and other resources. However, sometimes the phenomenon of incomplete combustion of fuel occurs in the operation of straw boilers. This paper will analyze the first. What are the causes of incomplete combustion?
1. If the temperature of the furnace is not enough, it is impossible to build a good combustion structure when the temperature of the furnace is lower than 600 C. The air supply can not meet the need of complete combustion of combustible components in the fuel.
2. Enough air: However, due to poor mixing contact, combustion disorder is caused; the moisture content of the base fuel used by the boiler is too large, when the moisture content in the fuel exceeds 45%, it is difficult to ensure that the combustion can be normal;
3. Fuel particles are too large: it is not conducive to combustion reaction; reaction time of combustion is insufficient or vibration amplitude of grate is too large, interval is too short, combustion time is insufficient;
4. Too much ash and coke particles are wrapped to slow down combustion or feed too much. The material layer on the grate is too thick to mix gas and solid properly. There is little feed or insufficient heat storage capacity in the thin layer of grate.
