What is Wood Pulp?
Trees are not just used to make wood and paper. There are other by-products of trees that we actually use every day. One of these products is wood pulp. If you have eaten a burger, used soap or dried yourself with a rayon towel before then you have used wood pulp. Find out what wood pulp is and what are the uses of this versatile wood by-product from this wood pulp guide.
Wood pulp explained
Wood pulp is from trees, cotton and other plant materials. This is a lightweight, strong material that is safe to use and ingest. Wood pulp is so easy and cheap to manufacture. During the paper making process, wood pulp is made by breaking down recycled paper or wood chips but there are also different ways to produce wood pulp depending on which type of product that needs to be manufactured. The following are the most common types of wood pulp used:
Chemical Pulp
This is wood pulp obtained by digestion or cooking of wood using various solutions or chemicals. Paper produced from this pulp is strong and resistant to color changes. Chemical pulps are not just for making paper. It is also used to create shipping containers, printing and writing papers, paper bags and other products that require strength.
Dissolving Pulp
This is a special grade of chemical pulp made from wood that is used in making regenerated or cellulose derivatives such as acetate used in the film, shiny fabrics, eyeglass frames and earlier forms of Lego bricks.
Fluff Pulp
Another type of wood pulp is a fluffy kind. This is made using a combination chemical and mechanical process that bleaches and presses the pulp material. This type is used as an absorbent medium in diapers, sanitary napkins, bed pads, and other personal hygienic products.
Mechanical pulp
This is any kind of wood pulp manufactured wholly or in part by a mechanical process. This includes stone-groundwood and chip mechanical pulp. This processing has a larger yield compared to using chemicals because of a high residual lignin or glue content left in the pulp after the entire process. But despite this, paper created after a mechanical process is weaker and thinner. The pulp created is useful in making newspaper papers, specialty papers, tissue, paperboard, etc.
Recovered paper pulp
This is wood pulp made from recycled paper. This is paper from newspapers, magazines, office papers, cardboard boxes, shoe boxes, cereal boxes and more. Recovered paper is combined with water in a pulper that works like a blender. This separates and mixes the fiber to create a mixture with a consistency of cottage cheese. Depending on the desired consistency of the final product, the recovered paper may be further processed to remove other impurities. The recovered paper pulp is very useful in creating products such as paper, envelopes, cardboard and more.
There several ways to process wood chips to make wood pulp. In chemical pulping, wood chips are cooked or digested. The wood fiber is separated into different components: cellulose fibers, lignin, and sugars. The pulp is washed and separated from other substances such as lignin. This is screened to further clean it and the result is a mixture that looks like a slurry. This will be further washed and bleached depending on its use.
Another way to create wood pulp is by mechanical methods. The wood is ground and wood chips are heated and fed to a machine with rotating discs. The chips are broken up into smaller chunks and then into individual fibers. The product is blended with water to create a thick slurry mixture and then dried.
The slurry is then passed through a variety of presses and heaters to remove any excess water. Wood pulp is naturally light brown in colors. It may be bleached to make white copy paper. An example of unbleached wood pulp paper is paper grocery bags.
Conclusion
Wood pulp is a by-product of wood. It is used to make the paper as well as many other products and a wide variety of materials. There are many types of wood pulp and these were manufactured depending on its use. Wood pulp can be made from raw wood or from recycled paper and other paper products.
