Paper and board

CeUulose is the most abundant polymer, an estimated 10 t being produced aimuaUy by natural processes. SuppUes for the rayon industry can be obtained from many sources, but in practice, the wood-pulping processes used to supply the needs of the paper and board industries have been adapted to make the necessary speciaUy pure grade. Of the 3 x 10 t of wood used by the paper and board industry (13) in 1989, about 6 x 10 t were purified to provide the 2.5 x 10 t of dissolving pulp required by the viscose processes. 

H. C. Schwalbe, Paper Web Transactions of the Cambridge Symposium, Vol. 2, British Paper and Board Makers Association, London, 1966, p. 692. 

The cahper is the thickness in p.m of a single sheet measured under specified conditions (TAPPI T411). CaUpers for a number of common paper and board grades are capacitor tissue, 7.6 p.m facial tissue, 65 p.m newsprint, 85 p.m offset bond, 100 p.m linerboard, 230—640 p.m and book cover, 770-7600 pm. 

As of 1995, the forest industry in the United States employed about 1.6 million people and produced products valued at over 200 biUion each year, approximately 20 biUion of which was in exports. There were 350 pulp mills, 600 paper and board mills, and ca 4500 converting plants in the United States producing ca 30% of the total world production. The United States and Western Europe, which represent ca 13% of the world population, consumed about 60% of production. 

The total production of the U.S. paper industry in 1994 was ca 85 million metric tons with a compound aimual growth rate over the previous decade of 2.7%. The domestic production of paper and board plus imports and minus exports maintains a remarkably constant ratio with real gross domestic product in the United States. One sector of the paper industry that has grown at a higher rate than GDP is recycled papers and boards which is projected to grow at 6.8% aimuaHy. Over one-half of paperboard production in the United States is from recycled fiber, and the industry as a whole is expected to achieve 50% recovery rate for paper and board products by the end of the twentieth century (see Recycling, paper). 

Pigmented Coating Processes for Paper and Board, TAPPI Press BookNo. 28, Technical Association of the Pulp and Paper Industry, Atianta, Ga., 1962. 

Pulp production and per capita consumption of paper and board for 1992 is shown in Table 8. The United States, Canada, Sweden, Finland, and Norway make up the North American and Scandinavian (NORSCAN) countries and produced about 63% (22.8 million tons) of the world output. Market share is growing for producers in Latin and South America, Western Europe, Asia, and Africa. These areas provide low cost pulp from state-of-the-art mills. Mills in the third world countries often enjoy the benefits of plentiful, fast-growing tree species, such as eucalyptus and tropical pines, and lower operating and labor costs (3). 

In recent years, lumber production has accounted for close to 40% of all roundwood used ia the United States (4). Pulp, paper, and board products have accounted for close to 30% of total roundwood used. Between 1965 and 1994, aimual production of lumber (ia board feet) iacreased by 26%. In contrast, production of paper and board (ia tons) more than doubled (4). 

An early approach was to use butadiene as the comonomer but the resultant copolymers have largely been used only in latex form in paper and board finishes and are no longer believed to be important. 

Latices of butadiene-methyl methacrylate copolymer have been used in paper and board finishes. 

De Beer, J. Worrell, E. and Blok, K. (1998). Long-Term Energy-Efficiency Improvements in the Paper and Board Industries. Energy 23 21-42. 

There is growing interest in the use of cereal straws such as wheat straw for animal feed after increasing its digestibility by various methods, or as a raw material for paper and board production. This is particularly important in areas with limited forest resources (1). For all these purposes a good physicochemical characterisation of cereal straw is necessary. 

Paper and board are composed of cellulose obtained by the mechanical or semi-chemical treatment of vegetable fibers (pulp) derived from various sources like wood, hemp, cotton, etc. In some cases waste and regenerated paper is used. 

The paper and allied products industry comprises three types of facilities pulp mills that process raw wood fiber or processed fiber to make pulp paper and board mills that manufacture paper or board and converting facilities that use these primary materials to manufacture more specialized products such as writing paper, napkins, and other tissue products. The process of converting paper is not a source of water or air pollution, as is the case for the first two facilities. This chapter focuses primarily on the greatest areas of environmental concern within the pulp and paper industry those from pulping processes. 

Inks, another contaminant of secondary fibers, may be removed by heating a mixture of secondary fibers with surfactants. The removed inks are then dispersed in an aqueous medium to prevent redeposition on the fibers. Continuous solvent extraction has also been used to recover fibers from paper and board coated with plastics or waxes. 

Monthly average 0.623 kg/Te Source U.S. EPA, Guidance Manual for Pulp, Paper, and Paperboard and Builders Paper and Board ... 

Abstract Paper for recycling is the most important fibre raw material of the German paper industry. 16.3 Mio t of paper for recycling was utilised in 2010 corresponding to 72% of the total fibre raw material input for paper and board production. In comparison to the used virgin fibre-based chemical and mechanical pulp, the utilised amount of paper for recycling is about 2.6 times higher. 

Of course, foodstuff should be free of harmful or potential harmful substances -and so also free of mineral oil. Which measures could be taken and are reasonable to avoid the transfer of mineral oil from paper and board packaging material into foodstuff is scrutinised critically in the following chapters. 

A total import of all required virgin fibre-based paper and board grades from other European countries to cover the German demand or from outside Europe to cover the European demand would currently fail due to unavailable capacities. 

These estimations can be documented by the well-known example with the diisopropylnaphthalene (DIPN) contamination in mixed RCP (RCP grade 1.02). This chemical substance comes from NCR carbonless copy paper and is in this mentioned RCP grade on an average level of 23 mg/kg TS [13], despite the fact that since several years those papers tried to be separated in the RCP grade sorted office paper , coloured letters and carbonless copy paper to reduce the DIPN concentration in mixed papers and board. 

By control and substitution of chemicals used in the paper mills, manufacturers of packaging papers and board can contribute themselves directly to a small mineral oil reduction in their products. Some additives contain mineral oil as solvent such as flocculation or retention aids based on polyacrylamide (PAA), resin sizing agents or defoamers. A change of such products to mineral oil-free additives removes their own mineral oil input and reduces the contamination of packaging material. In the area of retention aids based on PAA, this conversion has already mostly taken place. 

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