Economics from biomass

Chemicals have long been manufactured from biomass, especially wood (sHvichemicals), by many different fermentation and thermochemical methods. For example, continuous pyrolysis of wood was used by the Ford Motor Co. in 1929 for the manufacture of various chemicals (Table 20) (47). Wood alcohol (methanol) was manufactured on a large scale by destmctive distillation of wood for many years until the 1930s and early 1940s, when the economics became more favorable for methanol manufacture from fossil fuel-derived synthesis gas. 

Dong, Y. Steinberg, M., Hynol—an economical process for methanol production from biomass and natural gas with reduced C02 emission. In 10th World Hydrogen Energy Conference, Block, D. L., Veziroglu, T. N. Eds., Beach, Florida, June 20-24,1994, pp. 495-504. 

Such intensive use of land will make very large demands on available water supplies and soil corrosion is also an important issue. There is even a debate over the overall reduction in fossil energy use and actual contribution to C02 abatement for the case of ethanol production from com [9]. Since waste arises from biomass or fossil fuel, to introduce waste products in the conversion scheme, which of course should be done, does not help in the overall scheme we discuss here. This is bom out by economic predictions (Table 1.2). 

Another cause of activity loss is carbon deposition, which can be avoided if a high steam to carbon (S/C) ratio is employed [45, 46], However, economic evaluations indicate that the optimum S/ C ratio tends to be low. The presence of tars in the reforming reactor enhances coking and it is the main cause of carbon formation in reforming a gas from biomass thermal conversion [29]. 

A thorough analysis of value chains and the development of alternative value chains starting from biomass derived feedstocks, including assessment of the economic viability of the transformation of the chains, is required. This should be followed by the identification of easy entry points for the implementation of novel value chains. Technical key issues are generic methods to cope with the variability of raw materials derived from biomass and higher susceptibility to contamination by microorganisms and suitable catalysts for biorefineries. 

A second reason for the slow substitution of biomass for fossil fuels is an economic one. The economic issues of hydrogen production are dealt with in Chapter 15. Hydrogen produced from fossil fuel under conditions in which carbon dioxide is sequestered is compared with the economics of hydrogen produced from biomass. 

Cellulose is found in nature in combination with various other substances, the nature and composition of which depend on the source and previous history of the sample. In most plants, there are three major components cellulose, hemicelluloses, and lignin. Efficient utilization of all three components would greatly help the economics of any scheme to obtain fuel from biomass. Hemicelluloses, lignocellulose and lignin remaining after enzymatic degradation of the cellulose in wood would require chemical or thermal treatment - as distinct from biochemical - to produce a liquid fuel. 

It can be concluded that the biochemical production of liquid fuels from biomass is technologically feasible, but much work is still needed to optimize the various aspects of the processes. The present day economic climate is not favourable for production of these fuels from biomass by biochemical routes. 

Fraser, M.D., Henry, J-F., and Vail, C.W., Design, Operation and Economics of the Energy Plantation, 371-395 in Sympo-sium Papers Clean Fuels from Biomass, Sewage, Urban Refuse, Agricultural Wastes, Inst, of Gas Technol., Chicago (1976). 

Despite many advantages of using ethanol produced from biomass as a fuel (it is a high-energy, clean-burning, and totally renewable liquid fuel), it will only substitute gasoline if it is economically competitive. Thus, there is an increased interest in the optimization of all the steps of ethanol production. 

Foam fractionation is a promising technique for concentrating proteins because of its simplicity and low operating cost. One such protein that can be foamed is the enzyme cellulase. The use of inexpensively purified cellulase may be a key step in the economical production of ethanol from biomass. We conducted foam fractionation experiments at total reflux using the cellulase component P-glucosidase to study how continuous shear affects P-glu-cosidase in a foam such as a fermentation or foam fractionation process. The experiments were conducted at pH 2.4, 5.4, and 11.6 and airflow rates of 3,... 

The strategy for the development of products from biomass needs to be twofold. One approach is to identify those opportunities where we can compete economically with existing petrochemical products. Succinic acid-derived materials fit into this category (Fig. 1). The second approach must include the identification of products with novel functionality that cannot easily or cost effectively be derived from petrochemical building blocks. The challenge with developing new materials is that the market for these products must also be developed and the time and cost can be significant however, the reward may also be substantial. 

Brazil is a very large country with a warm and rather humid climate, which permits large, economical production of biomass. Nowadays, wood and charcoal are responsible for 25.7% of the total energy supply in the country. So, the intensive utilization of energy from biomass does not represent something really new. 

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