XINLI BOILER

How to solve the problem of insufficient combustion of biomass boiler fuel

18 Jan, 2022

　　1. How to solve the problem of insufficient fuel combustion in biomass boilers

　　The fuel of biomass boiler is biomass briquette fuel, which is mainly made of wheat straw, livestock excrement, rice straw, corn stalk, peanut shell, and three industrial wastes, which are environmentally friendly and energy-saving fuels. If this fuel is fully burned, the economic benefits brought by it are even greater. However, many users report that the fuel combustion is not sufficient, what should I do? Then let me introduce to you the conditions for sufficient combustion of biomass boiler fuel:

　　enough furnace temperature

　　The full combustion of biomass boiler fuel first requires a high furnace temperature, which can meet the needs of full combustion of the fuel, and the combustion rate must be proportional to the temperature.

　　the right amount of air

　　If the air volume is too large, it will cause the furnace temperature to decrease and increase the incomplete combustion of fuel; if the air volume is insufficient, the combustion efficiency will be reduced, that is, the fuel is wasted and the flue gas emission will increase.

　　Good mixing of fuel and air

　　In the combustion stage of the biomass boiler, it is necessary to ensure that the air and fuel are fully mixed, and in the burnout stage, the disturbance should be strengthened. Ensure that the fuel stays in the grate and the furnace for a long enough time, so that the combustion will be more sufficient, the combustion efficiency will be improved, and the cost will be saved.

　　Reasonable flame front position

　　2. What is the difference between wood pellet fuel and coal

　　1. Comparison of carbon content. The carbon content of biomass boiler fuel particles is less, and the highest carbon content is only about 50%, which is lower than the calorific value of coal-fired boilers.

　　2. Comparison of hydrogen content. Biomass boiler fuel particles contain slightly more hydrogen and have significantly more volatility. Most of the carbon in biomass is combined with hydrogen to form low-molecular hydrocarbons, and after reaching a certain temperature, they are thermally decomposed and volatiles are precipitated. Therefore, biomass fuels Easy to ignite.

　　3. Comparison of oxygen content. Biomass boiler fuel particles contain more oxygen, and its oxygen content is significantly more than that of coal, which makes biomass fuel low in calorific value.

　　4. Density comparison. The density of biomass fuel is lower, obviously lower than that of coal, the texture is looser, and it is easy to burn out.

　　5. Comparison of sulfur-containing lean. The sulfur content of biomass fuel is low, mostly less than 0.12%, and the boiler does not need to be equipped with a desulfurization device.

　　6. The CO2 released by biomass is very low, which can be considered as zero CO2 emission compared to coal-fired boilers.

　　7. The ash after biomass combustion can be used to make fertilizers, and the waste can be recycled, which is difficult for fossil fuel coal.

　　8. Biomass can be mixed with coal to improve combustion efficiency.

　　9. The use of biomass burning can realize the reduction, harmlessness and resource utilization of biomass waste.

　　3. Comparison of various energy operating costs (the most accurate thermal efficiency algorithm in the industry)

　　The operation cost analysis is illustrated by taking 600,000 kcal (one ton) hot water boiler as an example, as follows;

　　line cost analysis

　　Calorific value ÷ fuel calorific value ÷ thermal efficiency × fuel unit price = operating cost

　　Biomass particles: 600000kcal÷4200kcal÷88%×0.85 yuan/kg=137.7 yuan/hour

　　Natural gas: 600000 kcal ÷ 8500 kcal ÷ 92 % × 2.83 yuan / cubic = 217 yuan / hour

　　Light diesel oil: 600000 kcal÷10200 kcal÷92 %×5.6 yuan/kg=358.2 yuan/hour

　　Electricity: 600000 kcal ÷ 860 kcal ÷ 95% × 0.7 yuan/kw= 514 yuan/hour

　　Full-load boiler operation cost: 137.7 yuan/hour biomass pellets

　　217 yuan/hour natural gas

　　358.2 yuan/hour light diesel