Residue sawmill

Charcoal is produced commercially from primary wood-processing residues and low quaUty roundwood in either kilns or continuous furnaces. A kiln is used if the raw material is in the form of roundwood, sawmill slabs, or edgings. In the United States, most kilns are constmcted of poured concrete with a capacity of 40 to 100 cords of wood and operating on a 7- to 12-d cycle. Sawdust, shavings, or milled wood and bark are converted to charcoal in a continuous multiple-hearth furnace commonly referred to as a Herreshoff furnace. The capacity is usually at least 1 ton of charcoal per hour. The yield is - 25% by weight on a dry basis. 

The particleboard industry has grown rapidly since its beginning in Europe during the Second World War. The original development was in response to the demand for an inexpensive panel product which could be produced from low-quality wood unsuitable for plywood. In the mid 1950 s the particleboard industry was established in the United States not in response to a demand for the product but in response to the availability of cheap residues generated by planer mills and sawmills. 

In 1971, Marra and Maloney of Washington State University were interviewed regarding their pilot-plant research on bark board (45). They predicted that a shortage of easy-to-use sawmill and plywood plant wood-type residues would lead composition board manufacturers to seek bark, logging slash, and reclaimed waste paper as a source of furnish. Some potential problems with bark were discussed, especially that bark naturally possesses lower strength properties than wood of the same species. 

The growth in the use of wood residues has been substantial. By barking the sawlogs, the slabs, edgings, and other trimmings that formerly were burned now can be used to make pulp. Almost 28 percent of the wood used by the pulp industry is classified as waste wood. Several mills have been built that use no logs whatsoever but depend on residuals from satellite sawmill operations. Special sawmilling equipment has been developed to produce sawdust of a proper size so that it too can be used. 

In Austria the market for biofuels is established. Wood pellets, wood chips from forestry and sawmill residues have quite stable prices depending on supply and demand. The Price for pyrolysis oil is assumed to be the production cost calculated according (6). The price and the transport cost of the fuels used for the applications in this paper are listed in Table 3. The transport costs are calculated with a fixed and a variable con onent. The calculation is based on transportation by truck from the site of production to the site of use (storage of the biomass plant). 

Steam turbine CHP industry CHP for industry 116000 Sawmill residues... 

We consider material-recycling ratios of timber scrap (including board scrap), sawmill residues, and paper scrap, which are specified in the wood biomass flow (Figure 2). 

Raw material costs for sawmill residues such as bark, and agricultural residues such as straw, do not include any value for the materials. Straw cost does include baling, however. Production is based on 6 TPH. 

King of Prussia, PA. and the Tennessee Valley Authority. Mr. C. Robert Enoch of Forest Energy was interested in the system primarily for the charcoal production capabilities. His plans were to use the 2kD unit at a conventional sawmill site and to supplement the mill s residue supply with residues from nearby sources. 

Natural fibers can be classified as seed fibers (such as cotton), bast fibers (like flax, hemp, jute, kenaf, ramie), hard fibers (like sisal), fi-uit fibers (like coir), and wood fibers. The chemical composition and dimensions of some common agro-fibers are presented in Table 5.21. The origin of wood fibers can be sawmill chips, sawdust, wood flour or powder, cutter shavings, pulp or wood residues. As binders for these fibers, both thermosetting (like phenolic, epoxy, polyester) resins and thermosetting matrices [such as polyethylene (LDPE, HDPE), polypropylene (PP), poly(vinyl chloride) (PVC), polystyrene (PS)j can be used. Thermoplastic composites are, however, less expensive to process than thermosetting composites, in addition to their ability to be manufactured into complex shapes. 

Wood Residues Industrial wood residues are coproducts of the sawmilling industry like shavings, sawdust, and wood chips as well as residues of other parts of forest industry. Sawmilling residues are mainly used as a raw material for board as well as pulp and paper industry. The other residues are mainly used for heat and/or power generation. On a global scale, data on production and consumption of industrial wood residues are not available. According to Mantau [28] in 2008 the amount of industrial wood residues in Germany was 24.1 million m (cf. Table 4.5). 

Particleboard. Particleboard is prepared using small dried-particles combined with a thermally curable adhesive or other suitable binder and bonded together under high heat and pressure into panels of the desired thickness. The raw materials used to produce particleboard consist of wood wastes from sawmills, primarily from milled or groimd wood chips, sawdust, and planer shaving. In some cases recycled cellulosic materials and plant residues such as wheat straw and bagasse are utilized as fiimish to make particleboard. Most particleboard is formed into flat panels. However, molded and extruded particleboard products such as furniture parts, molded door skins, and molded pallets are also produced. 

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