Chemicals, biomass wood pulps

As with pulping and bleaching, biotechnology too could have a considerable impact on the production of chemicals from wood and other forms of plant biomass. The effects of biotechnology probably will be noticed first in areas of enzymatic hydrolysis of polysaccharides and fermentation technology. 

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). 

Biomass can generate energy in many different forms. Refuse derived fuels (MSW) can produce steam or electric power. They can also be converted to other fuels using chemical or biological processes producing ethanol or methanol. The wood and pulp industries use their wastes to provide a significant part of their heat, steam, and electricity needs. 

THE TERM PULP is used to describe theraw material for the production of paper and allied products such as paper-board, fiberboard, and dissolving pulp for the subsequent manufacture of rayon, cellulose acetate, and other cellulose products. More specifically, pulp is wood or other biomass material that has undergone some degree of chemical or mechanical action to free the fibers either individually or as fiber bundles from an enbodying matrix. Paper,... 

Pulp and paper refers to the processes employed to convert wood fiber into paper and allied products used in such applications as communications, packaging, and construction. Pulp and paper technologies or processes capitalize upon the anatomical, physical, and chemical properties of wood and, to a much lesser extent, other sources of biomass. The application of those technologies or processes has led to the development of a highly capital intensive industry with worldwide sales on the order of 100 billion per year. 

Various pulping technologies for wood and other biomass have been used for centuries to produce fiber, primarily for paper production. These processes effecbvely separate and clean the cellulose for use as fiber. However, the hemicellulose and lignin byproducts are not typically used for chemical products. The depolymerized hemicellulose in pulping liquor is a large source of biomass carbohydrate that could potentially be used for chemical producbon. 

These are mainly processes of the pulp and paper industry, which consumes most of the biomass, nearly exclusively wood, to produce cellulose for paper, packing and tissues. Most applied chemical processes for the breaking down ligno-cellulose are shown in Figure 5.3. 

The natural polymer lignin is extracted from biomass, mainly wood by various technologies as described above. It accumulates in masses up to more than 50 x 10 tons at chemical pulp mills every year, worldwide, as a by-product of the pulp and paper industry [48]. When using it for material development, the most abundantly available types of lignin are modified by chemicals on extraction depending on the type of process and these might be used for their identification [53-55]. 

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