Product Code Database
Pulpwood can be defined as timber that is ground and processed into a fibrous pulp. It is a versatile natural resource commonly used for Papermaking but also made into low-grade wood and used for chips, energy, pellets, and engineered products.
Pulpwood can be derived from most types of trees. Categorizing trees into hardwood and softwood is the easiest way to characterize types of paper produced from pulpwood.
Hardwoods are raw material that are preferred for pulp used in printing papers. It has small dimensions in its fibres, which can be useful for small-scale uniformity, opacity, and surface smoothness, all important for printing paper. (2025). 9780080431529, Elsevier. ISBN 9780080431529
Softwoods are the preferred raw material for strong papers, due to the length and slimness of the fibres. Low-density softwoods, such as firs with thin-walled fibres are preferred for papers with high demands for bonding-related strength characteristics. Some of these characteristics include tensile, burst, and surface strength.
Trees raised specifically for pulp production account for 15% of world pulp production, while old growth forests account for 9% and second/third plus generation forests account for the balance.
Trees of any size can be used for pulpwood, but trees that are 5-9 inches in diameter at breast height are normally used. These trees are cut after a saw timber harvest or as a separate operation to thin a crowded stand. Low-quality stands are completely harvested for pulpwood to regenerate the forest to more desirable species, as well as larger trees with disease or defects that prevent their use for lumber.
Additional fields of application include , wood-facings, , , and more. Furniture is another application of hardwood. Furniture made of pure solid wood is relatively rare. Most parts of furniture such as table boards, shelves or cabinet doors belong to wood-based materials because of their glued components. Solid wood can be used for chairs, tables, beds, upholstery frames, sideboards, cabinets, bathtubs, and more.
Hardwood is also used for interior work, such as parquet flooring, doors, and windows. Hardwood is especially preferred for parquet flooring. Tree species in darker colours are commonly used to give the flooring a "used look," for visual appeal. Solid wood is used for front doors and windows, while internal doors are mainly made of wood-based panels.
Structural products such as cross laminated timber, are mainly composed of softwoods. Particle materials are ideal to use low-rate timber assortments and saw mill waste. Types of particle materials include particle board, mineral-bonded wood composites, oriented strand board, laminated strand lumber, and oriented strand lumber.
Fibre materials include , insulating fibreboards, wood particle mouldings and wood plastic composites. The quality and processing of fibreboards and insulating fibreboards are influenced by the fibre percentage, the geometrical structural of the fibre, and the specific chemical composition of wood. The fibres of hardwoods are short, smooth and thin, and are suited for the dry production process because they do not mat. Ironically, hardwoods are barely used for fibreboards and insulating fibreboards.
Chemical modification, heat treatment, and impregnation (with salts, metals, and ) are the most used methods.
Wood can also be used as an energy source, with sawmill waste and low-rate timber. Combustion, wood gasification, and production of bioethanol are the three main ways hardwood is used for energy.
Combustion: split billets, chips and wood pellets. High-density wood species burn down slower, and the heat value depends on wood moisture content. Burning rate decreases with increasing density.
Wood gasification (synthetic natural gas and biomass to liquid): synthesis gas production is done by wood smouldering.
Bioethanol: start off by the splitting of cellulose and hemicelluloses in sugar by enzymes and acids, then the fermentation of the sugar with the aid of microorganisms. Lastly, the distillation and dewatering creates the bioethanol.
Although they are called 'softwood,' trees, they are not actually softer (in texture) in comparison to hardwood trees. The term just refers to wood that comes from gymnosperms or conifers. Some hardwood trees are even softer than specific softwood tree species.
Softwoods are used in wood manufacturing as well, and are sometimes preferred over hardwoods depending on the product being constructed. An important characteristic that softwoods have that make them a suitable pulpwood to build with, is that they can easily absorb any kind of finish. They can become very resistant and last for a long time (centuries). Softwoods tend to be cheaper than hardwood due to their growth rate and development being faster. They are versatile, strong, and can be managed easily. Some of the biggest softwood forests can be found in Canada, Scandinavia, and Russia.
Pinewood: Mostly found in the Northern Hemisphere, this type of wood is mainly used for domestic applications. It is resistance to shrinkage, swelling, and warping. It is used for outdoor wooden projects, such as decks. A disadvantage of pinewood is that over time, the wood could splinter, and items constructed from the specific type of pinewood used for making outdoor furniture/decks should be checked annually to prevent any risks to the people using them.
Firwood: This type of wood comes from Douglas Fir trees, and can be found in North America, Europe, North Africa, and Asia. It is strong and resistant to abrasion, and can be used for a diverse array of products. Some include furniture, doors, windows, and larger-scale items such as bridge parts, log homes, and commercial buildings. It can also be used for boat-building and aircraft construction, due to its sturdy and stable nature.
Redwood: This is mainly used for outdoor applications because of its resistance to weather conditions, insects, and rot. As a result of these characteristics, it is a premium building wood. It is another type of wood used to build decks, because of its natural strength, stability, and lifespan (can last a long time).
Wood is broken down mechanically or chemically. After the breakdown process, fibres (composed of two kinds of cellulose) and lignin are leftover. Lignin is the glue or cement that holds the fibres in wood together. Simply putting it, wood pulp is a large amount of individual wood fibres with the lignin removed. Wood pulp is naturally between dark brown to light grey in colour. Dark brown wood pulp is used for paper bags and boxes, and bleaching the pulp produces higher grades of paper (among other products).
Pulp grinders are usually powered by electric motors and automatically loaded. Most ground-wood pulp flows directly to an adjacent paper mill for use as stock. It is then formed into a sheet on a cylindrical vacuum filter, then pressed in a hydraulic press to a moisture content of about 50 percent. The pressed sheets result in the formation of bales.
Generating heat and electricity from wood-fuel is a multi step process.
The ash created during the pyrolysis process contains nutrients that are used as plant fertilizer, but it could also contain contaminants from the soils of the trees origin site.
Some of the potential sources of wood-fuel include early thinnings from commercial plantations, the residues from timber harvesting and arboricultural activities, coppicing and sawmills.
In the logging of mixed forest stands, the better are usually used for sawlogs for lumber production, while the inferior trees and components are harvested for pulpwood production. Pulpwood usually derives from four types of woody materials in a mixed logging operation:
Natural forest stands may also be harvested solely for pulpwood where, for various reasons, the value of the trees as sawlogs is low. This may be due to the predominant species in the forest stand (for example, some aspen forests in northern North America), or to the relative proximity of the nearest sawmill or pulp mill.
Plantations are full of trees similar to forests, but they differ greatly. A forest is a complex, self-regenerating system, consisting of soil, water, microclimates, energy, a diverse ecosystem with a wide variety of plants and animals in mutual relation. In contrast, a commercial plantation is a cultivated area whose species and structure have been simplified dramatically to produce only a few goods, such as lumber, fuel, resin, oil or fruit. The trees in a plantation have a small range of species and ages, and require extensive and consistent human intervention.
Pulpwood is also harvested from plantations established for the specific purpose of growing pulpwood, with little or minimal sawlog production. Monoculture of species intended specifically for pulpwood include Pinus taeda and Pinus elliottii pines in the southern USA; various species of eucalyptus (most commonly Eucalyptus globulus and Eucalyptus grandis) in Latin America, Iberian Peninsula, Australia, south-east Asia.
Plantations normally replace crops, grasslands, or scrub forests. Since they are used for commercial necessities, they are established on healthy soil, with their objective being short cycles of rapid growth that requires a certain level of fertility and water supply. Therefore, they tend to occupy areas already being used by local people.
Salvage cutting is the removal of trees that have been killed or damaged by insects, disease, wind, ice, snow, volcanic activity, or wildfire. The purpose of salvage cutting is to recover the economic value of trees before they decay. Dead trees decay quickly, and the timing of salvage cutting is crucial to capture as much economic value as possible. Post-fire salvage cutting helps manage fuels and future fire behaviour, as long as logging slash is treated after the harvest.
Sawdust gives very short fibres that are suitable as part of the furnish for paper tissue and writing papers. Saw blades have become thinner and with smaller teeth making the sawdust too small as fibre source.
| 16.0 |
| 24.6 |
| 17.3 |
| 4.8 |
| 7.1 |
| 6.8 |
Wood pulp has many modern-day uses other than paper-making and the other applications mentioned in the "Softwood Applications," and "Hardwood Applications" sections. Their uses can range from hygiene products to innovation medical products.
Wood can also be used as raw material for new bio-products, such an environmentally friendly textile manufacturing technologies. There are a few ways pulpwood is being used to develop technologies that consume less energy and fewer chemicals.
|
|
