Biomass sources

The means by which synthetic gaseous fuels could be produced from a variety of biomass sources are variable and many of the known gasification technologies can be appHed to the problem (70,71,76—82). For example, the Lurgi circulatory fluidized-bed gasifier is available for the production of gaseous products from biomass feedstocks as well as from coal (83,84). 

Wood is one of our most important renewable biomass resources. Unlike most biomass sources, wood is available year round and is more stable on storage than other agricultural residues. In the United States, wood residues from iadustrial by-products totaled 60.8 x 10 metric tons ia 1993 (73). Increasiagly, residues are iacorporated iato manufactured wood products and are used as a fuel, replacing petroleum, especially at wood-iadustry plants (73) some is converted to charcoal but most is used ia the pulp and paper iadustry. Residues are also available for manufacturiag chemicals, generally at a cost equivalent to their fuel value (see Fuels frombiomass Fuels fromwaste). 

Another emerging area m biofuels is pyrolysis, which is the decomposition of biomass into other more usable fuels using a high-temperature anaerobic process. Pyrolysis converts biomass into charcoal and a liquid called biocrude. This liquid has a high energy density and is cheaper to transport and store than the unconverted biomass. Biocrude can be burned in boilers or used in a gas turbine. Biocrude also can be chemical by altered into other fuels or chemicals. Use of pyrolysis may make bioenergy more feasible in regions not near biomass sources. Biocrude is about two to four times more expensive than petroleum crude. 

Lobbying by other P-carotene producers — In addition to approvals of mixed carotenes from palm oil, P-carotene from Dunaliella microalgae, and other natural products, the EU Health and Consumer Protection Directorate General was asked for an opinion on the safety of P-carotene from a dried biomass source, obtained from a fermentation process with Blakeslea trispora for use as a coloring matter for foodstuffs. 

Figure 1.13 Traditional petrochemical and proposed new biomass sources to consumer goods.

Table 1.2 Typical Literature Reported Heating Values for Various Biomass Sources...

Biomass Source Heating Value, Btu/Lb Reference Source... 

Uncertainties with the availability and suitability of biomass resources for energy production are primarily due to their varying moisture content, and to a lesser degree to their chemical composition and heating value. As the moisture content of biomass increases, the efficiency of thermal conversion process decreases. At some point more energy may have to be expended to dry the biomass than it contains. Uncertainties can be reduced by conducting a detailed chemical and physical analysis of the biomass sources. 

Figure 3.2 Summary of hydrogen production routes from biomass. (Source Milne, T.A. et al. Hydrogen from Biomass State of the Art and Research Challenges, NREL, IEA/H2/TR-02/001).

Generating hydrogen from such waste materials may turn out to be one of the least expensive methods of producing hydrogen since this resource is quite extensive. It has been estimated that in the U.S., roughly 14 quads of the annual 64 quad total energy requirement could be met from renewable biomass sources, which is about 20% of our total energy needs. 

The expansion of the market, however, will depend considerably on the possibility of an efficient use of other biomass sources, particularly lignocellulosic-based materials, fast growing dedicated crops, and waste resources. Effective integration of bioethanol production into biorefineries will also be a key aspect in decreasing the price by a better use of all the components of biomass. 

Biofuels are easily available from common biomass sources... 

Compound Group Molecular Tracers Biomass Source... 

The economic potential of enzyme hydrolysis is therefore dependent upon the evolution of (1) cheap, readily available, large biomass sources, (2) cheap and efficient pretreatment methods, and (3) cheap and potent sources of cellulolytic enzymes. 

When contrasting processes in the energy and chemical industry with processes using biomass sources, which are in general more efficient What could be the reason for this ... 

Carbohydrates, in the form of gums, polysaccharides, oligomers, and monomeric sugars, are readily obtainable from renewable biomass sources. Each of these has potential use in the formulation of adhesives. This has been true historically and will be increasingly true in the future as petroleum-derived chemicals become scarce and their prices rise. 

Carbohydrates are readily available from renewable biomass sources. In this introduction, I have given a broad overview of how carbohydrate polymers,... 

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