What are the characteristics of biomass fuel

Biomass fuel properties

1. The carbon content is low, and the carbon content of biomass fuel will not exceed 50%, which is equivalent to the carbon content of lignite. In particular, the content of fixed carbon is significantly lower than that of coal, so the fuel burns for a shorter time and has a lower energy density.

2. There are many volatile components. Most of the carbon in the fuel is combined with hydrogen to form hydrocarbons with low molecular weight. It is easy to decompose and decompose volatiles when heated. The energy contained in the volatile components accounts for more than half of all its energy. Sufficient black smoke will be produced to pollute the environment.

3. The high oxygen content makes biomass flammable and does not require too much oxygen supply.

4. The density of biomass fuel is small, it is easier to burn out, and the residual carbon in the ash is less, but it is not good for the transportation of fuel.

Similar to the combustion of coal, the combustion process of biomass fuel can be divided into four stages: preheating, drying, volatile precipitation, and coke burning. Thermal decomposition begins at 250°C, and nearly 80% of volatiles can be precipitated at 325°C. The precipitation time of volatile components is very short. If the ventilation is insufficient, the volatile components may be eliminated without complete combustion, resulting in black smoke or even thick yellow smoke. After the volatiles are burnt out, the remainder of the fuel is loose coke, and the airflow movement will wrap a part of the carbon particles into the flue to form black flocs. Therefore, if the ventilation is too strong, the combustion efficiency will be reduced. The combustion of fixed carbon is affected by the difficulty of infiltration of air wrapped in ash, and it is easy to leave carbon residue.