Wood residues

Larch Gum. Larch gum [37320-79-9] (larch arabinogalactan) is obtained by water extraction of the western larch tree, iLarix occidentalism the heartwood of which contains 5—35% on a dry wood basis. In the early 1960s, a countercurrent hot water extraction system was developed, and the gum was produced commercially by the St. Regis Paper Co. under the trade name Stractan. The potential production capacity of this gum is 10,000 t/yr based on the wood residues from the lumber industry. However, the product could not compete with gum arabic, and commercial production is now limited to small batches for a specific medical appHcation. [Pg.436]

Wood Residuals. Chips, sawdust, and other residuals such as planar shavings are used as a primary source of fiber for some pulp mills. Chips are screened and placed in a purchased chip pile. Sawdust and other residuals obtained from wood processing plants must be cooked separately and requite special digesters and handling equipment. These materials may also be burned as hog fuel. [Pg.256]

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). [Pg.331]

One of the most promising substrates for future production of microbial biomass is the ceUulose contained in agricultural residues such as wood pulp, sawdust, feed-lot waste, com stover, rice huUs, nut sheUs, and bagasse, aU of which contain ceUulose as the principal carbon source. CeUulose contents range from 90% in cotton to 15—20% in dicotyledon leaves. Wood residues and grasses contain mixtures of ceUulose, hemiceUulose, and lignin. The major... [Pg.393]

Pulp and paper manufacture is increasing in the world at an exponential rate. The demand for paper will continue as new uses are found for this product. Since most paper is manufactured from wood or wood residue, it provides an excellent use for this renewable resource. [Pg.89]

Solid fossil fuel and wood residue-fired... [Pg.412]

Sulfur dioxide reduction to achieve required emission levels may be accomplished by switching to lower-sulfur fuels. Use of low-sulfur coal or oil, or even biomass such as wood residue as a fuel, may be less expensive than installing an SO2 control system after the process. This is particularly true in the wood products industry, where wood residue is often available at a relatively low cost. [Pg.491]

The forest products industry encompasses a broad spectrum of operations which range from the raismg of trees, through cutting and removing the timber, to complete utilization of the wood residue (17). [Pg.513]

Catechol is also obtained from coal coking and from certain wood residues. Vanillin (synthetic vanilla flavoring) is a catechol derivative. Resorcinol and hydroquinone are currently made by the same type of chemistry used... [Pg.87]

Lentinus lepideus, and the chemical effects of decay of the wood by the mold were progressively followed by periodic analyses of the resulting wood residues. The results of this decay are presented in Table 2. [Pg.79]

In the U.S. about 8% of the energy is provided by biomass and almost 90% of this comes from the combustion of wood and wood residues. The use of biomass increased from an installed capacity of 200 megawatts in 1980 to over 7,700 megawatts in 1990. The search for cleaner fuels and landfill restraints are the main reasons for increased biomass utilization. The cost of waste disposal has soared and landfill sites are closing faster than new ones are opening up. The Environmental Protection Agency (EPA) estimated that between 1978 and 1988, 70% of the nation s landfills, about 14,000 sites closed. [Pg.88]

The direct combustion of wood and other plant matter has been a primary energy source in the past. Any type of biomass can be burned to produce heat or steam to turn a generator or perform mechanical work. Direct combustion is used in large power plants that produce up to 400 megawatts. Most direct combustion systems can use any type of biomass as long as the moisture content is less than 60%. Wood and wood residues are commonly used along with a number of other agricultural residues. [Pg.91]

Solid biomass in the form of wood products and wood residues can be imported to a maximum of 30% of the total additional primary input of forestry biomass, which represents about 9.7 Mtoe. [Pg.152]

The market is fast-growing in the USA where there is a considerable amount of wood residues of low prices comparable with those of inorganic fillers such as talc and calcium carbonate. [Pg.75]

Forest products Wood, logging residues, trees, shrubs and wood residues, sawdust, bark, etc. [Pg.45]

The wood pyrolysis is attractive because forest and industrial wood residues can be readily converted into liqtrid products. These liqtrids, as erode bio-oil or slurry of charcoal of water or oil, have advantages in transport, storage, combustion, retrofitting and flexibility in production and marketing (Demirbas, 2007). In the first step of pyrolysis of carbohydrates dehydration occtrrs and at low temperatures dehydration predominates. Dehydration is also known as a char-forming reaction. Between 550 and 675 K volatile products, tar, and char are formed. The volatile products are CO, CO, H O, acetals, furfural, aldehydes and ketones. Levoglucosan is the principle component in tar. [Pg.52]

Tuttle with co-workers constructed a wood combustion facility including a spreader stoker unit (Figure 5). A mechanical spreader distributed wood residues evenly across the grate. The overfire region was surrounded by a water-wall construction. [Pg.58]

The fuel could be supplied at four rates. The fuel was wood residue consisting of a mixture of bark and wood. Below are some fuel data ... [Pg.59]

Three laccase preparations (I, II and III) were isolated from the racellular culture medium of Coriolus versicolor by consecutive fractionation through Sephadex G50 and DEAE Sephadex A25 (84). The laccase III preparation at pH 4.0 reduced the apparent molecular weight of a lignin-derived fraction that had been obtained by eluting the water-soluble extract of a cellulase treated ezomatsu wood residue through... [Pg.264]

Figure 14. Change (solid line) in apparent molecular weight distribution of water-soluble extract from a cellulase-treated ezomatsu wood residue (dotted line) at pH 4.0 brought about by the laccase HI preparation from C. versicolor, Sephadex GIO/H2O elution profiles adapted and redrawn from reference 85.

Unused wood residues as a by-product of current forest operations in Canada are estimated to be of the order of 0.14 billion cubic metres ( ). Apart from what is presently being utilized, there exists an estimated annual roundwood surplus of some 0.2 billion cubic metres. Associated with this surplus would be a further 0.2 billion cubic metres of wood residues. If this wood were easily accessible and available at reasonable cost, it could be converted to methanol or fuel oil equivalent to about two-thirds of Canada s annual petroleum products production. In Ontario, Hall and Lambert (3 ) have estimated available quantities of surplus wood in several categories. [Pg.135]

Based on currently proven energy plantation area In Ontario of about 500,000 hectares and poplar yields of about 9 oven-dry tonnes per hectare per year (about 4 oven-dry tons per acre per year) plus about one million tonnes per year of wood residues. These feedstock quantities would produce about 2-3% of the total petroleum consumption. Some additional production is possible by expansion of the energy plantation area. (An additional one and one-half million hectares would increase the percentage liquid fuel production to about 8-10%.)... [Pg.159]

The forest energy potential of Canada has been surveyed ( ). The available material is essentially of 3 types. The lowest cost material is wood residue at the existing forest industry processing sites. While about half of the mill... [Pg.169]

The list of plants, by-products and waste materials that can potentially be used as feedstock is almost endless. Major resources in biomass include agricultural crops and their waste by-products, lignocellulosic products such as wood and wood waste, waste from food processing and aquatic plants and algae and effluents produced in the human habitat. Moderately dried wastes such as wood residue, wood scrap and urban garbage can be directly burned as fuel. Energy from water-containing biomass... [Pg.176]

Figure 8. Delignification on heating (A) spruce wood meal with phosphate buffer (pH 6.8), 150°C (B) spruce wood meal with dioxane-phosphate buffer (60 40% v/v) (C) wood residue from (A) (48 h) with dioxane-phosphate buffer (60 40% v/v).

On heating wood meal with a mixture of dioxane and phosphate buffer for 48 h at 150°C, 24% of the lignin dissolved, as shown in Figure 8. Most of this lignin is hydrophobic and eluted in the retention time range GO-GO minutes (Curve B). However, when the wood residue obtained after heating wood meal with phosphate buffer was heated with the dioxane-phosphate buffer mixture, only moderate further delignification was obtained (Curve C). [Pg.43]

Reactive extraction of lignin from red spruce has been studied using supercritical methylamine and methyla-mine-nitrous oxide binary mixtures. The wood residues and precipitated fractions after extractions have been characterized by chemical and spectroscopic procedures. [Pg.49]

Figure 2 shows the extent of dissolution of red spruce in methylamine, the amount of precipitate collected in the first trap upon complete depressurization to 1 bar, and the Klason lignin content in the wood residue after extraction, as functions of extraction time. The total dissolution and precipitation are normalized with respect to oven dry weight of initial wood. The extraction conditions were 185°C, 275 bar, and 1 g/min solvent flow rate. As shown in the figure, dissolution initially increases with time and levels off at about 28% by weight. The precipitates which were collected as solids follow a similar trend. The Klason lignin content of the wood residue decreases with extraction time, from an initial value of 26.5% down to 10.1% after 5 h of extraction. [Pg.53]

Wester, R.C., Hui, X., Barbadillo, S. et al. (2004) In vivo percutaneous absorption of arsenic from water and CCA-treated wood residue. Toxicological Sciences, 79(2), 287-95. [Pg.274]

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