WOOD

The Uses of WOOD

Pulp and paper, construction, packaging and cooperage, furniture, destructive distillation products (charcoal), extraction products (turpentine, rosin, tall oil, pine oil, etc.), methanol, plywood, fuel, rayon and cellophane, flock.

Definition

A mixture composed of 67–80% holocellulose and 17–30% lignin, together with low percentages of resins, sugars, a variable amount of water, and potassium compounds. Its fuel value varies widely around 3000–6000 Btu/lb according to variety, moisture, etc. Combustible.

Agricultural Uses

Wood is a hard, dead tissue obtained from the trunks and branches of trees and shrubs. Woody tissue is also found in some herbaceous plants.
Botanically, wood consists of xylem tissue which is responsible for the conduction of water around the plant. A living tree trunk is composed of (beginning from the carter) the pith (remains of the primary growth), wood (xylem), cambium (a band of living cells that divide to produce new wood and phloem), phloem (conducting nutrients made in the leaves), and the bark. The wood nearest to the cambium is termed sapwood because it is capable of conducting water. However, the bulk of the wood is heartwood in which the xylem is impregnated with lignin, which gives the cells extra strength but prevents them from conducting water in temperate regions. The age of a tree can be found by counting its annual rings. Commercially, wood is divided into hardwood (from deciduous angiosperm trees) and softwood (from gymnosperms). Wood is mainly used in paper and pulp industry, construction, furniture making, rayon and cellophane manufacture. It is also used in places as domestic fuel for cooking. The fuel value varies widely around 7000 to 14OOO J/g according to the wood variety, moisture content, etc.
Wood is a mixture of three natural polymers cellulose, hemicellulose and lignin. Chemicals derived from wood include bark products, cellulose, cellulose esters, cellulose ethers, charcoal, dimethylsulphoxide, ethyl alcohol, fatty acids, furfural, hemicellulose, haft lignin sulphonates, pine oil, rayons, resin, sugars, tar oil, turpentine and vanillin. Most of these are direct products or by-products of wood pulping, in which the lignin, that cements the wood fibers together and stiffens them, is dissolved away from the cellulose. The other materials developed from wood are solid wood products (including lumber, veneer and plywood laminated timbers, insulation board, hardboard and particle board) and fiber wood products (paper and paperboards)