Wood, paper from

T.N. Smith, D.H. LeMessurier and W.R. Wood, paper from the Dept, of Chem. Engng., University of Adelaide, 1980 (limited distribution). 

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. 

Fiber Slurry Pipelines. Pipelines to carry suspensions of wood, paper, sludge, etc, have found commercial acceptance. Most of them are less than 15 km long but have diameters of up to 500 mm. These slurries are often concentrated and display viscous plastic properties, although particle sizes may vary special pumps are used. One such hydrotransport system carries a cellulose slurry by pipeline from the plant to a paper plant near Heidenau, Germany. The 250-mm dia pipeline carries 60 t/d over the 3-km distance to thickeners. In Sweden, a 3.7-km, 500-mm dia pipeline moves cellulose by... 

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). 

The separator must be stmcturaHy sound to withstand the rigors of battery manufacturing, and chemically inert to the lead—acid cell environment. Numerous materials have been used for separators ranging from wood, paper, and mbber to glass and plastic. The majority of separators used are either nonwoven—bound glass or microporous plastic such as PVC or polyethylene. 

There has been only one major use for ozone today in the field of chemical synthesis the ozonation of oleic acid to produce azelaic acid. Oleic acid is obtained from either tallow, a by-product of meat-packing plants, or from tall oil, a byproduct of making paper from wood. Oleic acid is dissolved in about half its weight of pelargonic acid and is ozonized continuously in a reactor with approximately 2 percent ozone in oxygen it is oxidized for several hours. The pelargonic and azelaic acids are recovered by vacuum distillation. The acids are then esterified to yield a plasticizer for vinyl compounds or for the production of lubricants. Azelaic acid is also a starting material in the production of a nylon type of polymer. 

Fuel. Wood, paper, coal, and gas are just a few of tlie products commonly tliought of as fuels. However, from a chemical standpoint, tlie conunon fuel elements are carbon (C) and hydrogen (H). Carbon is found in coal, coke, lignite, and peat. Otlier carbon fuels include fat, petroleum, and natural gas. Hydrogen is conunonly found in conjunction witli tliese carbon compounds. 

There has been a rapid growth of the demand for plastics from less than 20 billion pounds in 1970 to nearly 50 billion pounds consumed in the United States in 1986, mostly due to the substitution of traditional raw materials. All over the world, plastics have replaced metals, glass, ceramics, wood papers, and natural fibers in a wide variety of industries including packaging, consumer products, automobiles, building and construction, electronics and electrical equipment, appliances, furniture, piping, and heavy industrial equipment [57-121]. Consumption patterns of PBAs in some countries are shown in Tabies 1 and 2. 

The three classes of fire are A those started from wood paper or rags B those started from oil, grease, or flammable liquids C those initiated by electricity. 

Lignin must be removed during the production of cellulose and paper from wood pulp. This is an expensive operation and produces pollution. Genetic engineering is being used to produce trees with reduced amounts of and more easily extracted lignin. 

SCA-Billerud A variation of the sulfite process for making paper from wood, in which the waste hydrogen sulfide is burnt to sulfur dioxide and used to make sulfuric acid. 

The development of polystyrene is by no means finished. On the contrary. The opinion is often put that the heyday of thermoplastics - and thus of polystyrene - is over and gone, because the raw material from which they are made, crude oil, continues to increase in price and is in short supply. However, this view is superficial, because what is overlooked is the fact that traditional materials (metals, glass, porcelain, ceramics, wood, paper, wool, cotton, etc.) cannot be produced without energy. If the total energy balances for different materials and their processing are compared, it will be seen that plastics, including polystyrene, come off better than their competitors. Plastics, compared with these other materials, require very little energy for fabrication (9J, 92, ... 

Multipurpose dry chemical extinguishers (20-A 80B-C) should be provided in warehouses and shop buildings where wood, paper, plastics, and other flammable solids, as well as flammable liquids, may be stored. In grease manufacturing and compounding or similar operations where little or no wood, paper, and similar combustibles are stored, but where flammable liquids may be prevalent, potassium bicarbonate dry chemical extinguishers should be used. Extinguishers should be located not more than 75 ft (23 m) away from any potential Class A fire hazard and not more than 50 ft (15 m) from Class B fire hazards. 

Carbon monoxide is found in varying concentrations in unventilated and confined spaces resulting from partial oxidation of carbonaceous matter. Burning wood, paper, kerosene, or other organic materials in inadequate air can produce this gas. It also is found in automobile exhaust and tobacco smoke emissions. 

Cellophane is, after chemical modification, obtained from the cellulose in wood, just as paper (from cellulose and lignin), cellulose fibres ( rayon ), and cellulose plastics. Leather is made from animal hides in a tanning process. 

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