Paper mill
From Free net encyclopedia
Template:For Image:InternationalPaper6413.JPG A paper mill is a factory devoted to making paper from wood pulp and other ingredients using a Fourdrinier Machine or similar apparatus. These establishments have been noted for producing an obnoxious smell in the general surroundings.
The undesirable odour (usually at pulp mills, which are a little different from paper mills) is caused principally by process by-products, specifically the hydrogen sulfide and other reduced sulfur gases resulting from the cooking process. Thankfully, these airborne particles are not harmful to the health of the community in commonly occurring concentrations, but they are considered a nuisance. The Kraft process of reducing wood logs to their fibre constituent is primarily responsible for the odour, as opposed to the sulfite process.
Paper mills can be fully-integrated mills or smaller processing mills. The integrated mill will receive the whole forest log (or wood chips), process it down to the individual fiber level and into a 4% (approximately) pulp slurry, then process that pulp slurry into a sheet of paper. Non-integrated mills cannot process the log or wood chips but instead purchase preprocessed pulp slurry in a dried and baled form, known as market pulp, from pulp mills. The pulp bales are then rehydrated into a 4% solution in order to be processed into a sheet of paper.
A paper mill is known to have operated in Baghdad as early as 794. The technology spread from East Asia to Europe by way of the Muslim world.
The modern paper mill uses large amounts of energy, water, and wood in a highly efficient and extremely complex series of processes, using modern and sophisticated controls technology to produce a sheet of paper that can be used in incredibly diverse ways. Modern paper machines are very large and can be 500 feet in length, produce a sheet 400 inches wide, and operate at speeds of over 100 mph.
Mills
- Braviken Paper Mill, Norrköping, Sweden
- UPM Kymmene, Finland
- Södra Cell Folla, Norway
- Hurlburt Paper Mill, Lee, Massachusetts
- Crane Paper Company, Dalton, Massachusetts (A large supplier of paper for the U.S. dollar)de:Papiermühle