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2. Press section
When it comes out of the wet end, i.e. at the end of the flat table or former, the sheet of paper does not yet have all the physical properties required for its final use. It is still very wet and therefore very fragile: it requires what is known as a "consolidation" phase. This is the main role of the press section. The second important function of this part of the machine is to remove as much water as possible mechanically, by dewatering, before using the much more energy-intensive thermal process in the dryer as a last resort.
The pressing principle is based on compressing the fibrous mat between two rollers, at least one of which is covered with felt. Part of the water contained in the sheet, sandwiched between these two rollers, flows in liquid form into the receiving felt. This water is then extracted from the felt by means of suction boxes.
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Press section
Dryer
Economic data
According to the annual Pulp and Paper International survey published in July 2002, world production in 2001 amounted to 179,374,000 tonnes of pulp and 318,147,000 tonnes of paper and board (tables 1 , 2...
Specific consumption
Paper manufacturing consumes thermal energy, particularly in the dryer, and electrical energy at all stages of the process.
Paper manufacturing also consumes water at the various stages of pulp preparation, additives and on the paper machine. Some of this water is recycled (see wet-end circuit), while the surplus is sent to the wastewater treatment plant. Finally, it generates waste (sludge,...
Bibliography
Articles and books for [J 6 900]
Standards
Numerous standards have been specially designed for the paper industry, both for the classification and quality assessment of pulp, paper and board, and for the definition of the finished product. In France, paper industry standards are either AFNOR (NF Q standards), ISO (from the ISO/TC 6 technical committee) or CEN (EN standards) (from the CEN/TC 172 technical committee).
Please refer to the current...
Organizations
COPACEL (Confédération française de l'industrie des papiers, cartons et celluloses), which includes the following organizations:
PROCELPAC (French association of manufacturers of cellulose-based packaging materials) ;
French grouping of printing and writing paper manufacturers;
Syndicat des fabricants de papiers...
Manufacturers. Suppliers
Given the diversity of materials and equipment used by pulp, paper and board mills, it is not possible to provide an exhaustive list of manufacturers and suppliers. For this reason, various directories have been specially published for the paper industry, bringing together all the players in the profession.
Europa Birkner. Directory of the European paper industry. Producers, Converters,...
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