Pulp (paper)
From The Art and Popular Culture Encyclopedia
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Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibres from wood, fibre crops or waste paper. Wood pulp is the most common raw material in papermaking.
History
Using wood to make paper is a fairly recent innovation. In the 1800s, fibre crops such as linen fibres were the primary material source, and paper was a relatively expensive commodity. The use of wood to make pulp for paper began with the development of mechanical pulping in Germany by F.G. Keller in the 1840s, and by the Canadian inventor Charles Fenerty in Nova Scotia. Chemical processes quickly followed, first with J. Roth's use of sulfurous acid to treat wood, followed by B. Tilghman's U.S. patent on the use of calcium bisulfite, Ca(HSO3)2, to pulp wood in 1867. Almost a decade later the first commercial sulfite pulp mill was built in Sweden. It used magnesium as the counter ion and was based on work by Carl Daniel Ekman. By 1900, sulfite pulping had become the dominant means of producing wood pulp, surpassing mechanical pulping methods. The competing chemical pulping process, the sulfate or kraft process was developed by Carl F. Dahl in 1879 and the first kraft mill started (in Sweden) in 1890. The invention of the recovery boiler by G. H. Tomlinson in the early 1930s allowed kraft mills to recycle almost all of their pulping chemicals. This, along with the ability of the kraft process to accept a wider variety of types of wood and produce stronger fibres made the kraft process the dominant pulping process starting in the 1940s.
Global production of wood pulp in 2006 was 160 million tonnes (175 million tons).
Chronology of the invention of wood pulp
1850 Friedrich Gottlob Keller of Germany devises a method of making paper from wood pulp. However the paper is of poor quality.
1852 Hugh Burgess, an Englishman, perfects the use of wood pulp by 'digesting' the wood with chemicals.
1867 C.B. Tilghman, an American chemist, improved the process of making paper from wood by using sulfites during the pulping process.
1879 C. F. Dahl, a Swede finally perfected the use of wood by adding yet another chemical. His 'sulfate' method spread rapidly and reached the United States in about 1907.
1883 Charles Stillwell invented a machine to make brown paper bags for groceries in Philadelphia. Today more than 20 million paper bags are used annually in supermarkets. Many of these are recycled into new bags and boxes.
1889 - 1900
Economical, mass produced paper became a reality. Paper production doubled to about 2.5 million tons per year. Newspapers, books, and magazines flourished. Paper found its way into schools, replacing the writing slate.
