Biomass is an important energy source for human survival. It plays an important role in the entire energy world, especially in developing countries. The biomass waste resources nowadays are mainly agricultural and forestry waste.
In the world's energy consumption, biomass consumption takes up 14% of the world's total energy, only after the consumption of oil, coal and natural gas, ranking fourth.
However, the utilization of biomass energy is not evenly distributed in the world. In many underdeveloped countries, the contradiction between energy supply and demand is very prominent. The gap between developing countries and developed countries is large, and the utilization of biomass energy is still backward.
Many crops, straw and forestry residues are discarded and incinerated, this creates significant biomass energy waste and contributes to environmental pollution.
What We Should be Doing: Accelerate the application of biomass briquetting technology in developing countries, improve the utilization rate of crop straw and forestry waste, reduce waste of biomass energy and environmental pollution. This will promote the sustainable development of the global economy.
Application Features of Biomass Briquetting
Biomass briquette has a lot of advantages. After the biomass is briquetted, the volume is reduced by 20 to 30 times, the density can reach 1 t/m3, the water content will be below 20%, which makes it convenient for storage and transportation.
It can be used as a bio fuel and is widely used in domestic cooking stoves, heating stoves, biomass gasifiers, boilers and biomass power plants, etc.
Biomass briquette fuel has better thermal performance than wood. The calorific value per unit volume is comparable to that of medium coal. The calorific value can reach 16,000 kJ/kg, and the “zero” emission of greenhouse gas carbon dioxide can be achieved.
Because the energy of biomass briquette fuel comes from natural photosynthesis, the solar energy fixed on plants, the carbon dioxide released during combustion comes from the growth of plants, is the absorption of carbon dioxide in the natural world. So the biomass briquette fuel is a kind of fuel with carbon dioxide "zero".
Compare to bio briquette, the burning of coal will increase the carbon dioxide content in the atmosphere, which will further aggravate the global warming effect.
The bio fuel briquette from bio waste has a fixed carbon content of 15.99%, a sulfur content of 0.05%, and a nitrogen water content of 0.14%.
This makes the biomass fuel briquette as a good low-carbon fuel, the sulfur and nitrogen content is low, and the pollutants generated by combustion are few. The sulfur dioxide can be reduced without desulfurization equipment, and the dust can be removed by a simple dust collecting device.
Biomass Fuel Briquette Production
Biomass briquetting follows this process: crush and dry agricultural and forestry waste (crop straw, rice husk, branches, bark, sawdust, etc.), control the moisture of raw materials at about 20%, then briquette under certain pressure (with or without heating) with a briquette machine and output various shaped bio fuel briquettes such as rods, granules, and blocks.
The agricultural and forestry waste is mainly composed of cellulose, hemicellulose and lignin. The lignin is a sky-fired polymer formed by photosynthesis. It has a complex three-dimensional structure and is a high molecular substance, which is about 15% to 30% in plants. When the temperature reaches 70-100 °C, the lignin begins to soften and produces a certain viscosity.
The biomass fuel briquette is mainly made with the adhesive effect of lignin. When the temperature is raised to 100-200 °C, lignin will turn molten and has a high viscosity. At this time, with a certain pressure, crushed bio waste will combine with and adhere to cellulose tightly, the volume is greatly reduced, and the density is significantly increased.
After the pressure is removed, the inelastic fibers are intertwined with each other. It can maintain the pressed shape, and the strength is further increased after cooling to become a familiar briquette fuel.
Biomass Fuel Briquette Benefits
Economic Benefits (data from China)
We take the biomass briquetting machine model MTSB-1 produced by Maxton Industrial Co., Ltd as an example, each unit is priced at 35,000 USD, the total power is 65kW, average productivity is 1.2 t/h, average straw acquisition The price is about 20 USD / t, and the price is about 60 USD / t after processing into straw briquettes.
In the process of briquetting, labor, electricity, maintenance, depreciation and management costs are about 20 USD per ton of biomass straw. That is, the processing of biomass briquettes can generate 20 USD / t. Each briquette machine is calculated according to the work of 200 days per year, working 8 h every day, 1.2 t per hour, that is, 1920 t per year, one machine a year The income can be generated by 38400 USD, and the purchaser can recover the investment cost in one year and obtain certain economic benefits.
Briquetting crop straw and forestry waste can create value and make them become a clean fuel. It can be widely used in household cooking, boilers, biomass power plants, etc. to reduce carbon emissions and avoid the atmosphere and environmental pollution caused by crop straw burning and disposal. It has significant social and economic benefits.