The thermo-chemical and physical characteristics of the biomass and together with the optimum design of the gasifier are parameters of crucial importance. Arid zone Journal of Engineering and Technology. How does Gasification Work; Available online at: In general, gasification technology is selected on the basis of available fuel quality, capacity range, and gas quality conditions. The inorganic residue is retrieved as a glass like substance Eulerian-Eulerian granular multiphase flow model approach is capable of predicting the core-annulus structure in CFB.
Eljummah This work is licensed under a Creative Commons Attribution 4. Biomass gasification in Circulating fluidized beds CFB is one of the most promising conversion processes in meeting future ecologically compatible and sustainable energy demand, based on a combination of flexibility, efficiency, and environmental acceptability. This method produces gas with higher energy content compared to previous methods. Gas Quality The product gas formed from biomass gasification contains both combustible and noncombustible components. Insulation for the Reactor The gasifier reactor needs to be properly insulated for two reasons:
All gasifier fuels produce dust. Gas cleaning strategies for biomass gasification product gas, International Journal of Low-Carbon Technologies ; 7: Jian Xu and Li Qiao.
Biomass resources and bioenergy potentials in Nigeria; African Journal of Agricultural Research8 Updraft or Countercurrent Gasifiers In this type of reactor, air is taken in at the bottom, and the gas leaves at the top. Fuel Moisture Content Biomass materials exhibit a gasifkcation range of moisture content and since this affects its value as a fuel source, fluet is important that the flkent be stated whenever moisture content is measured Other parameters like thickness of insulation and sizes of materials can also be computed Oxygen gasification can be achieved by removing Nitrogen from air prior to supplying to the gasifier.
There are two principal types of fluidized bed gasifiers namely, bubbling fluidized bed BFB and circulating fluidized bed CFB.
They evaluated various biomass energy conversion technologies and their applications to developing countries such as Nigeria. Guo, and He M.
Height of the Reactor The height of fluenh reactor determines the time the gasifier can be operated continuously and the amount of gas that can be produced for a fixed column reactor. In the case of limited angle, scraper or scoop will be needed to properly discharge the ash or the char.
CFD Modeling and Simulation on Hydrodynamics of CFB Biomass Gasifier using FLUENT
Md Risat et al. It is dependent on the feedstock heating value and bulk gasificagion. The major components are carbon, oxygen, and hydrogen. The amount of pressure exerted depends on the thickness of the column as well as the nature of the fuel and the char, at various superficial gas velocities.
The ash content of a fuel and the ash composition has a major impact on trouble free operation of gasifier. For fixed gasifictaion gasifiers, like the down-draft reactor, the fuel can be fired starting from the top Top Lit or from the bottom Bottom Lit of the reactor.
It is one of the most attractive alternatives systems of energy. Yashwant 8 reviewed methanol production using producer gas in fuel cell and small scale irrigation systems for developing countries. The reactor diameter is thus 51 They are mainly divided into: The results show that small particle size favours gas composition. How does Gasification Work; Available online at: Introduction Biomass represents one of the largest sustainable energy resources in the world and has been perceived as an attractive source of power, fuels and other chemical products.
Assessment of Biomass Gasification: A Review of Basic Design Considerations
Solving the tar problem is mostly an issue of tar cracking in the combustion zone. The thickness of the fuel bed is only considered when designing a cross-draft gasifier. It depends on the fuel used to raise the temperature of the feed material before stimulating the production of the gas.
Dust Content All gasifier fuels produce dust. During the combustion process the organic matter in the husks carbohydrate and carbonaceous fractions is converted to carbon dioxide and water.
They are relatively easy to design and operate but have limited capacity.
A Review of Basic Design Considerations. Dilip and Vimal R. According to Mc Kendry 3most of the development work was carried out with common fuels such as coal, charcoal and wood. Deteriorated biomasses, such as those dumped on roadsides and along river banks for several months, were observed to be more difficult to gasify thesia the fresh ones.