Biogas fuel applications

The need to remove alkali material from the biogas stream depends on the end use for the gas. Problems associated with alkali vapor formation and deposition are critical in systems where the hot biogas is to be used without significant cool-down. Moderate gas cooling followed by removal of bulk particulates provides adequate cleaning for simple boiler systems that can tolerate some ash deposition. Other applications such as gas turbines require cleaner fuel gases. Since turbines operate at high rotational speeds, deposition can... 

Tars in the biogas can be tolerated in some systems where the gas is used as a fuel in closely coupled applications such as burners. In these situations, cooling and condensation can be avoided, and the energy content of the tars adds to the calorific value of the fuel. 

The most commonly used fuel - especially for stationary applications - is natural gas, although a variety of fuels have also been tested, such as waste biogas, landfill gas, or the products of coal gasification (after the removal of any sulfur-containing impurities that might poison the anode materials). 

Osaka Cas in Osaka, Japan (www.osakagas.co.jp) and Tokyo Gas in Tokyo, Japan (www.tokyo-gas.co.jp) both conduct a wide range of research for industrial combustion applications. Some examples include cogeneration, advanced fuel-air mixing, gas turbines, oxy-natural gas combustion, and biogas. 

The spread of biofuels has increased the applications of the double fuel burners, where a traditional fuel (for example gas) is used as a backup in case of a lack of the renewable resource. Use of bio-oil and biogas increased reliability problems on some specific burner components like pumps and valves. 

There are several potential industrial applications for the CMS membranes some which are close to market, others which may be more future applications. This may be a function of both the volume of the gas streams, and/or challenging process conditions. Closest to market is the upgrading of biogas to vehicle fuel and separation of air by the use of carbon membranes. 

Other possible fuels (Fig. 2.38) include biobutanol, biogasoline, biomethane (biogas), various furans (2,5-dimethylfuran, 5-ethoxymethylfurfural) and terpene derivatives (e.g. RJ-4). All of these have advantageous properties and some economic potential in certain application areas. 

Alves, H.J., Bley Junior, C., Niklevicz, R.R. et al. (2013) Overview of hydrogen production technologies from biogas and the applications in fuel cells. International Journal of Hydrogen Energy, 38, 5215-5225. 

The utilization of biogas in a CHP is the most common application. The effort needed for biogas cleaning is still low. The degree of efficiency for the production of power is arormd 40% (maximum 42%) in gas engines and 45% in dual fuel engines.The... 

Other Applications. Fermentation-based processes have also been developed for the mass production of certain materials. Most notably, these processes have focused on the bulk production of alternative fuels, particularly ethanol and other solvents, and biogas, which is primarily methane. Processes employing Clostridia bacteria, for example, are useful in the production of acetone and 1-butanol, two extremely important organic solvents. In addition, as the applied science and technology behind fermentation becomes more developed, other areas of science will use the ability to tailor microbial processes for the purposes of analytical and test procedures and production methods. 

The MCFC power plants are generally expected to be stationary applications with high efficiency. Clean natural gas, biogas from waste water (digester gas), and gasified biomass or coal are expected as a fuel. The plant capacity is sub-MW to several MW class as a distributed generators and is several hundred MW as a centralized station with coal gasifier in future. 

The biogas has different applications, such as a source for heat, steam, and electricity, household fuel for cooking, fuel cell, and can be further upgraded to vehicle fuel, or for production of chemicals and is a very promising technology for generating bioenergy [17,33, 34],... 

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