Biomass feedstocks potentially available

Table I. Biomass Feedstocks Potentially Available for Ethanol Fuel Production...

The potential of microbial processes has yet to be realized for the commercial syntheses of a large number of commodity organic chemicals. Biomass feedstocks, the availability of appropriate organisms, and also, therefore, the avail-... 

BIOMASS FEEDSTOCK MATERIAL POTENTIALLY AVAILABLE FOR ETHANOL PRODUCTION PRODUCTION POTENTIAL, MILLION GALLONS PER YEAR ETHANOL... 

In any case, the information and data discussed here show that although the amounts of certain animal wastes are substantial and represent a large energy potential, careful assessment of availabilities is necessary to develop strategies for commercial development of animal excreta as waste biomass feedstocks. 

Since a large portion of a feedstock s equivalent energy content can be expended for drying, there is a balance between the cost of moisture removal, the incremental improvement in efficiency on conversion, and the advantages of handling drier feedstock. The key biomass property that should obviously be examined, in addition to conversion process requirements, is the moisture content of the fresh biomass, the methods available for its partial or total removal, and the effects, if any, on the properties of the remaining biomass. The moisture content of biomass is as variable as the multitude of biomass species available as potential feedstocks. 

While all pyrolysis oil production reactor systems produce similar materials, each reactor produces a unique compound slate. The first decision, especially for a potential chemical or fuel producer, rather than a reactor developer, is to determine what products to make and which reactor system to use. The operating parameters of any reactor system designed to produce pyrolysis oil, especially temperature, can be altered to change the pyrolysis oil product composition and yield. Different feedstocks will produce different pyrolysis oil compositions and by-products, e.g. amorphous silica from rice hulls or rice straw, fatty acids from pine. Finally, feedstock pretreatment and/or catalysis, or reactor-bed catalysis can be used to improve specific product yields (7). Reactor system developers need to examine what they can produce and make this information available to chemical manufacturers and suppliers/owners of biomass feedstocks. This assumes that analysis of die entire liquid product from thermal conversion can be made, including quantitative analysis for any compounds that are being considered for recoveiy. Physical characterization - pH, viscosity, solids content, etc.is also needed. However, what can be produced is of no value, if it cannot be recovered or used economically. This involves examining the trade-offs between yield and current commercial value, recovery costs, and potential commercial value,... 

The present utilization of carbohydrates as a feedstock for the chemical industry is modest, when considering their ready availability, low cost and huge potential [92], The bulk of the annually renewable carbohydrate biomass consists of polysaccharides, but their non-food utilization is still modest. The low-molecular-weight carbohydrates, that is, the constituent units of these polysaccharides, are potential raw materials for several commodity chemicals in fact, glucose (available from cornstarch, bagasse, molasses, wood), fructose (inulin), xylose (hemicelluloses) or the disaccharide sucrose (world production 140 Mtons year-1) are inexpensive and available on a scale of several ten thousands. 

A case study and forecast for the explicit production of bulk chemicals from biomass in the region of Rotterdam has recently been provided by Van Haveren et al. [46], As technologies for the conversion of, for example, ethanol, glycerol, and sugars to glycols, iso-propanol, and acetone are well known and readily available, and as the prices for feedstock are well below the selling prices for the named products, there is a clear short-term potential for these bulk chemicals (Table 2.2.2). 

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