Biomass utilization

Large-scale gasification reactor technology based on EF gasification from (a) General Electric (GE Texaco process) and (b) Conoco-Phillips (E-Gas). (Adapted from Meier, D. Faix, O. Fast pyrolysis A route for energy and chemicals from wood—fluidized vs. ablative pyrolysis. In Wood and Biomass Utilization for the Carbon Uptake, Seoul National University, Seoul, 2005, pp. 55-68.)... 

Balatinez, J. J., The Potential of Densification of Biomass Utilization. Plenum Press, London, 1983, pp. 181-189. 

In the U.S. about 8% of the energy is provided by biomass and almost 90% of this comes from the combustion of wood and wood residues. The use of biomass increased from an installed capacity of 200 megawatts in 1980 to over 7,700 megawatts in 1990. The search for cleaner fuels and landfill restraints are the main reasons for increased biomass utilization. The cost of waste disposal has soared and landfill sites are closing faster than new ones are opening up. The Environmental Protection Agency (EPA) estimated that between 1978 and 1988, 70% of the nation s landfills, about 14,000 sites closed. 

The main drawback with the thermochemical route for biomass utilization is the strong dependence on scale-up. To be competitive, the capacity has to be of the order of a small oil refinery (approx. 1 million tonnes per year), but there then exists the problem of the cost of transporting the biomass relatively long distances to this production capacity. Pyrolysis or related technologies ( flash or fast ) could transform biomass into liquid products that are more easily transported, and these liquid products could then be the input for a large, centralized... 

Renewables Biomass utilization Residual and cultivated terrestrial and aquatic biomass can produce liquid or gaseous fuels suitable for the transportation sectors. 

The wide dispersion of pulverized coal boilers (in number and capacity) translates into significant potential opportunities for biomass utilization [44]. 

On the basis of biomass utilization it is possible in average to produce 7.5 million m3 biogas that is equivalent to 5,000 tons of conditional fuel. 

Bioenergetics Biomass, Bioengineering of Biomass Utilization, Limits of Bioreactors Catalysis, Industrial Coal Structure and Reactivity Combustion Energy Efficiency Comparisons Among Countries Energy Flows in Ecology... 

Pimentel, D., Limits of biomass utilization, in Encyclopedia of Physical Science and Technology, 3rd ed., Vol. 2, Academic Press, New York, 2002, pp. 159-171. 

Milne T.A., Abatzoglou N. Evans R.J. (1998) Biomass Gasifier Tars Their Nature, Formation and Conversion, lEA Biomass Utilization Task XIII, "Thermal Gasification of Biomass" activity report NREL/TP-570-25357, USA, Golden. 

Wood hydrolysis has been limited to cellulose degradation by cellulase enzymes. These en mes are typically low activity and highly inhibited by the glucose product. As mentioned above, mild acid pretreatment has been found to be an important first step in the biomass utilization process. The pretreatment is used both to break down the hemicellulose to sugars and to disrupt the lignocellulosic structure and tlie crystallinity of the cellulose. 

Following the depolymerization of the carbohydrate stmetune of the biomass, numerous separations will Ukely be required. These complex mixture separations are at the forefront of the process development effort for biomass utilization for chemicals production. Several technologies are available for other plications and are being developed for the specific needs of biomass processing. 

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