Fig. 1.2 An overview of the basic mechanical pulping procedures.

Introduction

A Short History of Mechanical Pulping

Jurgen Blechschmidt and Sabine Heinemann

Along with the development of mankind there has been an ever-increasing

Demand for writing materials. It is said that papermaking was invented in China

In the year 105 AD and, after a long journey, the procedure arrived in Europe in

Spain) and finally in Germany in 1390 (Nuremberg). When Gutenberg

Invented letterpress printing in 1445, to replace hand-written books with printed

Books, the demand for paper increased immensely. During this evolution, the raw

Materials used for paper have ranged from rags to hemp, and from flax and cotton

As well as worn-out hemp ropes.

Up until the end of the eighteenth century, paper was only made by hand, but

In 1799 Nicolas-Louis Robert developed the first papermaking machine in France

(Fig. 2.1).

Fig. 2.1 Papermaking machine, developed in 1799 by N.-L. Robert (1761–1826).

At about in the same time, in 1805, Bramah invented the cylinder machine in

England, and as a result of these inventions paper production was subsequently

Increased during the following years. The problem was that this increased production

Resulted in an increasing lack of raw materials.

In 1843, the Saxon weaver Friedrich Gottlob Keller (Fig. 2.2) successfully developed

the mechanical defibration of wood to produce groundwood. "Because this

Handbook of Pulp. Edited by Herbert Sixta

Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

ISBN: 3-527-30999-3

©2006 WILEY-VCHVerlag GmbH&Co.

Handbook of Pulp

Edited by Herbert Sixta

Epochal invention turned the paper production into a totally new direction, it represents

– together with the invention of the paper machine – one of the largest

technical progress since the invention of paper itself” [2].

Fig. 2.2 Left: Friedrich Gottlob Keller (1816–1895), the

inventor of stone groundwood. Right: the second version

of Keller’s grinding machine.

A Short History of Mechanical Pulping

Raw Materials for Mechanical Pulp

Jurgen Blechschmidt and Sabine Heinemann

3.1

Wood Quality

The quality of wood obtained from the forest is of special importance for mechanical

Pulping. This raw material that is useful for mechanical pulp and chemical

pulping is often also termed “pulpwood”. In mechanical pulping, the requirements

Of fiber wood are higher for grinding than for refining. The most important

requirements of fiber wood include:

_ Wood quality: The wood should be healthy, possibly grown

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