Most paper is made from forestry products, usually trees. The most common of trees that paper comes from are:. In most cases, the best parts of these trees are used for construction, and less desirable portions are used in pulp.
Natural fibers such as cotton are used in some cases because its fibers are very strong. This makes it an excellent choice for documents that may need to be archived. This strength, combined with its unique feel is why cotton paper is popular for letterhead and other corporate stationary products. Although many fibers were mentioned above, forestry products logs from trees are the source of most fiber in paper pulp. There are three main components, which must all be separated to make pulp. The bark protects the fibers of the log, which are held together by lignin.
The goal is to extract the fibers, and this is accomplished either using a chemical or mechanical process. Paper mills all work a little bit differently, so please keep in mind that these are generalizations.
Since most paper starts as logs, there is a significant amount of bark. Bark does not work well for making paper, so the first step in the mechanical pulping process is to remove the bark from the logs. This excess material becomes a biomass energy source to help power the paper mill.
In most processes, the logs are ground up using a giant machine containing a rotating disk and a fixed steel plate. Usually, heat and chemicals are used to aid in this process. Due to the "brute force" nature of mechanical pulping, both whole and partial fibers are created.
In addition, the lignin is not removed from the paper. This gives the paper a grey-yellow color. The mechanical pulping process uses significantly more energy than is produced by the biomass power generated by the bark. Papers made from mechanical pulps are also known as "groundwood fiber papers" and are typically very cost effective.
An example of this type of paper is newsprint. Like mechanical pulp, the process begins with whole logs. This is done with a large scale version of the the wood chippers that landscaping companies use. The wood chips are placed into a giant machine that combines them with really hot water and chemicals.
This helps remove air pockets so that the chips will break down into fibers more easily. Next, the wood chip and chemical mixture is moved into a pressure cooker. The wood chips spend about two hours at nearly degrees farenheit. The combination of steam, chemicals, and pressure causes the chips to desintegrate. Though Matthias Koops in England produced paper from wood pulp as early as , credit for the discovery of the industrial process for making wood pulp paper is generally given to the German machinist and inventor Friedrich Gottlob Keller , and to the Canadian poet and inventor Charles Fenerty , both of whom appear to have independently announced the discovery of similar processes in Fenerty began experimenting with wood pulp around On October 26, he took a sample of his paper to the leading newspaper in Halifax, Nova Scotia, the Acadian Recorder.
According to the Wikipedia he wrote the following letter on this piece of wood pulp paper:. The result has proved that opinion to be correct, for- by the sample which I have sent you, Gentlemen- you will perceive the feasibility of it. I entertain an opinion that our common forest trees, either hard or soft wood, but more especially the fir, spruce, or poplar, on account of the fibrous quality of their wood, might easily be reduced by a chafing machine, and manufactured into paper of the finest kind.
This opinion, Sirs, I think the experiment will justify, and leaving it to be prosecuted further by the scientific, or the curious. The Voelters, Christian and Henry, made numerous improvements in the machine, Christian Voelter obtaining patents in various European countries, in France even as early as April 11, Henry Voelter patented his improvement on the pulp machine in Wurtemburg, Germany, August 29, , and in the United States, August 10, Pearson C.
Chenney, ex-governor of New Hampshire, has described the difficulty of introducing paper made from wood. Chenney said: "When Mr. Russell built his mill at Franklin, those of us who were engaged in the manufacture of paper and had no knowledge of what could be done with wood supposed that his enterprise would ruin him.
We supposed that his material would be more like sawdust or clay.
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