Woods biomass resources

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 be a renewable feedstock for methane. Biomass feedstocks for methane production include crop residues, municipal solid waste (MSW), and wood resources. Biomass resources for the production of alcohol fuels are estimated at about 5 million dry tons per day which could provide 500 million gallons of methanol per day. 

The Renewables-Intensive Global Energy Scenario (RIGES) predicts a primary energy potential from biomass resources for Western Europe to be 14160 PJ/year by 2025 and 14 170 PJ/year by 2050 (Johansson et al., 1993). Thereby the biomass potential comprises resources from wood, energy crops, agricultural residues and industrial biomass residues. The estimates are based on the biomass production at that time in combination with assumptions of future growth rates. 

Fig. 1.15 Key global biomass resources from agricultural residues, wood, and herbaceous energy crops. (A. J. Ragauskas et al., Science, 311,484 (2006). Reprinted with permission from AAAS [7]).

Generally, two types of biomass resources can be considered in the discussion on renewable energy feedstock (1) primary biomass, such as energy crops, including switchgrass, poplar, and willow, and (2) biomass residues (primary when derived from wood or processed agricultural biomass secondary when derived from food or fiber processing by-products, or animal waste and tertiary when derived from urban residues).21... 

Municipal waste Residential, commercial, and institutional postconsumer wastes contain a significant proportion of plant-derived organic material that constitutes a renewable energy resource. Waste paper, cardboard, wood waste, and yard wastes are examples of biomass resources in municipal wastes. 

Although the feedstocks are widespread, they must be used locally since their bulk makes it costly to transport the feedstocks. In California, it has been uneconomical to transport wood residues more than 100 miles. The bulkiness of biomass resources can also cause storage problems. 

There is no single biomass for the energy industry. Rather, many companies are active in utilizing a variety of biomass resources. In most cases, the principal line of business of these companies is not biomass development but agricultural production, wood products manufacturing, distilling, and similar... 

The content of lignin in different types of biomass resources varies strongly it is especially high in wood (see Table 5.2). 

Beech wood chemical composition was previously investigated and presented (Bodirlau et al. 2007), this wood biomass resource comprising cellulose, lignin and ethanol extractives. 

Heat production is the most common conversion system for using biomass resources. Heat from wood and other biomass resources is utilized for cooking food, heating homes, and producing steam for industry. 

The direct labor inputs for wood biomass resources are 2-30 times greater per million kilocalorie than coal. In addition, a wood-fired steam plant requires 2-5 times more construction workers and 3-7 times more plant maintenance and opOTation workers than a coal-fired plant. Including the labor required to produce corn, about 18 times more labor is required to produce a million kilocalories of ethanol than an equivalent amount of gasoline. 

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