Few other studies of pulp and paper workers have shown increased risks for lung cancer. A Canadian study showed an increased risk among those exposed to paper dust (Siemiatycki et al. 1986), and US and Swedish studies showed increased risks among paper mill workers (Milham and Demers 1984; Torén, Järvholm and Morgan 1989).
The association between gastric cancer and pulp and paper work was first seen in a US study in the 1970s (Milham and Demers 1984). The risk was found to be even higher, nearly doubled, when sulphite workers were examined separately. US sulphite and groundwood workers were also found in a later study to run an increased risk of stomach cancer (Robinson, Waxweiller and Fowler 1986). A risk of the same magnitude was found in a Swedish study among pulp and paper mill workers from an area where only sulphite pulp was produced (Wingren et al. 1991). American paper, paperboard and pulp mill workers in New Hampshire and Washington state ran an increased mortality from stomach cancer (Schwartz 1988; Milham 1976). The subjects were probably a mixture of sulphite, sulphate and paper mill workers. In a Swedish study, threefold increased mortality due to stomach cancer was found in a group comprising sulphite and paper mill workers (Wingren, Kling and Axelson 1985). The majority of pulp and paper studies reported excesses of stomach cancer, though some did not.
shows the production of paper from wood pulp. Logs are first debarked. Stripped bark is then used for fuel or to enrich soil. Wood can be broken down into fibers by mechanical or chemical methods. In the mechanical process, wood fiber is physically separated from the wood by forcing debarked logs and hot water between enormous rotating steel discs with teeth that tear the wood apart or by pressing the logs against grindstones. The mechanical pulping process uses considerable amounts of electricity (2,000 kWh/ton of pulp) but has a high yield (about 90 percent). The wood requirements for mechanical pulping are less than in chemical pulping. Most of the electrical energy that goes into the refiner is liberated as steam, which is subsequently used to dry the paper. Mechanical pulp mills use about 8,000 gallons of water per ton of pulp produced. Bleaching of mechanical pulps is done with hydrogen peroxide or sodium hydrosulfite. Mechanical pulp constitutes about 10 percent of the pulp made in the United States. Recent technology has permitted the construction of mechanical pulp mills that have no liquid effluent. Their only waste is solid waste such as boiler ash. Wood that is chemically processed is chipped. The chips are passed through vibrating screens. Oversized chips and undersized particles (such as chips and dust) are discarded. Accepted chips are stored in huge bins ready for chemical processing. Most pulp produced in the United States is made with the Kraft chemical pulping process ().
To produce paper, the pulp is then screened, cleaned, and mechanically refined. Bales of pulp are dispersed in a huge volume of water so that the slurry is less than 1 percent fiber. The slurry is pumped through a narrow aperture onto a moving wire. The water drains (and is pulled) through the wire to produce a wet pulp mat. Water pulled through the wire is recycled. The wet pulp mat is pressed to remove more water and then is dried over a series of hot rolls to become paper. The water requirements of a paper machine are modest, about 5,000 gal/ton of paper, as much of the water is recycled. The energy requirement, mainly for drying the paper, is roughly 5,000 MJ/ton of paper. This energy often comes from other parts of the mill, such as the mechanical refiners in a mechanical pulp mill or the recovery or waste wood (hog fuel) boilers in a Kraft mill.
Paper recycling is on the rise, as shown in . To recycle fiber, the paper is slurried in water and then run through cleaning and screening operations to remove such contaminants as wire, plastics, paper clips, and staples. In some mills the pulp is also deinked. In mills without deinking processes, excess paper-machine white water is sufficient to run the recycle mill. With deinking, fresh water makeup is required. The volume of fresh water makeup can vary widely, from 1,500 gal/ton of pulp to almost 20,000 gal/ton of pulp, depending on the deinking system (Simons, 1994).
5, 2017 - Sappi Limited, a global producer of dissolving wood pulp, specialty and packaging papers, graphic (printing and writing) paper and biomaterials, has announced it will acquire the specialty paper business of Cham Paper Group Holding AG (CPG) for roughly US$149 million.
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11, 2017 - Andritz has received an order to modernize the stock preparation line in the sack kraft paper production line at Mariysky Pulp and Paper Mill in Volzhsk, Russia.
The cluster rule is a multimedia regulation that requires pulp and paper mills to meet base-line limits for toxic releases to air and water. The limits are expected to eliminate dioxin discharges and cut toxic air emissions by almost 160,000 tons annually. The pulp and paper mill cluster rule is the first issued by the Environmental Protection Agency to control the release of pollutants to two media—air and water—from a single industry. The rule allows pulp and paper mills to select the best combination of pollution prevention and regulatory requirements at one time. It also provides incentives for mills to adopt advanced pollution control technologies that lead to further reductions in toxic discharges. Mills volunteering for this program will be subject to more stringent reductions but will receive rewards for their participation, such as additional compliance time (United States Environmental Protection Agency, 1997b).
As a result, 75 per cent of the energy used in Domtar pulp and paper mills comes from renewable biomass sources, largely generated from wood processing and pulping byproducts.
Responsible sourcing and logistics
Domtar’s demand for locally sourced wood creates incentives for landowners to keep forests as forests.
As with the other manufacturing industries examined by the committee, regulation has been the dominant driver of environmental performance improvements in the pulp and paper sector. Until the 1980s, the industry's environmental focus was primarily on manufacturing. In the 1980s and 1990s, however, the industry came under additional pressures to improve its environmental performance as concerns related to unsustainable natural resource use, industrial pollu-
These concerns were captured in an address to the 1992 Conference of the Technical Association of the Pulp and Paper Industry by Peter Wrist, past president and chief executive officer of the Pulp and Paper Research Institute, Canada, in which he said, "Today, our industry is under savage attack by groups claiming that our operations are destroying irreplaceable natural treasures; poisoning the oceans, lakes and rivers; burying out cities under piles of garbage; and threatening the health of the public and the future of the world" (Wrist, 1992).