With the scarcity of fossil fuels like coal, oil, gas, etc., process plant managers prefer steam boilers that facilitate effective combustion with biomass fuel. Biomass is an ideal alternative for fuel sources as it is environmentally friendly that causes less emission and is easily available. Biomass fuel includes animal waste, industrial waste, agricultural waste, etc., that are economical and easy to procure. Fossil fuels are the primary energy source globally that would be depleted in the next 30-40 years. Biomass is one of the initial and earliest sources of energy, especially in rural areas. It makes it more accessible and affordable for the process plants located in remote rural areas. Biomass ranks as the fourth source of energy globally with approximately 14% of consumption. It is the primary source of energy for many developing countries.
Biomass for Combustion:
The combustion process involves the reaction of fuel with oxygen in the air to generate heat. Combustion requires three elements- fuel, air, and heat. With all three elements available in optimal proportion, proper combustion takes place without the wastage of fuels. Proper combustion occurs when fuel and air (fuel-to-air ratio) are mixed in precise amounts, for an adequate amount of time under proper conditions of turbulence and temperature. Air includes 21% of oxygen and 79% of nitrogen. Therefore, the result of stoichiometric combustion of biomass will consist of water vapor, carbon dioxide, and nitrogen to generate heat. Biomass is represented chemically as CH2O. Biomass is burned directly in the combustion process without any chemical treatment for steam generation. Biomass fuels show varying combustion characteristics, depending on their elemental composition.
Biomass combustion involves multiple chemical reactions in which carbon is oxidized to carbon dioxide while hydrogen is oxidized into water. For the combustion analysis, the fuel properties of biomass are classified broadly as physical properties, chemical properties, and thermal properties.
The thermal properties of biomass fuels consist of density; particle size, porosity, and shape distribution. The chemical properties of biomass fuels are the proximate analysis, elemental analysis, and higher heating value. Thermal property includes thermal conductivity, specific heat, and emission that vary with moisture content, temperature, and degree of thermal degradation.
Types of Biomass Combustion:
Biomass fuels can be ignited by various types of combustion processes such as fixed bed combustion, fluidized bed combustion, and pulverized bed combustion. Fluidized bed combustion is best-suited to burn biomass fuels of low quality, high ash content, and low calorific value compared to the limitations of other firing systems to meet the biomass fuel properties. Fluidized bed combustion offers significant advantages over conventional combustion systems, such as higher combustion efficiency, fuel flexibility, and low emission of harmful pollutants like SOX and NOX. Fluidized bed combustion provides benefits like low corrosion and erosion, easy ash removal, simple start-up, less excess air, quick response to load fluctuations, no soot formation, high reliability, low maintenance, high efficiency in power generation, and pollution reduction.
Impact of Biomass Fuel on Environment:
Combustion with biomass fuel significantly reduces SO2 by up to 75%. Plants absorb carbon dioxide as it grows, and plants used as biomass fuel can help in maintaining its balance. Compared to coals, the combustion of biomass fuels reduces the CO2 emissions by 93% and the alkaline ash generated during biomass ignition can capture CO2 and SO2 emissions. Additionally, the disposed waste leads to increasing pollution of water and air that affects the ecosystem. Utilizing the wastes as biomass fuels can accomplish reducing waste pollution. It also provides an excellent source of fuel for combustion. Fossil fuel combustion is one of the primary causes of pollution and can be reduced, by adopting biomass fuel for combustion.
Advantages and Disadvantages of Biomass Fuels:
Advantages of Biomass Fuels:
- Renewable Source of Energy
- Environment-Friendly
- Reduces Greenhouse Emissions
- Economical to Procure
- Convenient to Transport
- Replacing it with Non-Renewable Fossil Fuels Reduces High Emission
Disadvantages of Biomass Fuels:
- Requires Ample Space for Storage
- Requires Large Furnace Area and Volume for Combustion Process
Biomass fuels are expected to increase in usage with the changing times. As the various manufacturing and process facilities are following techniques to reduce greenhouse emissions and comply with environmental laws, biomass fuels are the ideal alternative for effective combustion with minimal emission.
Rakhoh Boilers have always aimed to strike a balance between advancement and sustainability since their inception in 1983. Our highly efficient and reliable steam boilers like Solid Fuel Bi-Drum, Combo X, Membrane X, Optipac, and Huskon are ideal for biomass fuel. The products offer effective combustion with biomass fuels like Wood, Briquettes, Bailed Bagasse, Wood Chips, Wood Logs, Rice Husk, Cotton Waste, Coconut Shell, Groundnut Shell, Biomass Pellets, etc. With more than 38 years of experience and expertise, we provide the best thermal solutions and after-sales services to over 20 process industries in our global network of 26 countries.
To know more about our products and services, visit www.rakhoh.com