Search Results - (Author, Cooperation:N. T. Oanh)

2012-01-17

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Aerosols ; *Air Pollutants/analysis ; Air Pollution/*prevention & control ; *Climate Change ; Computer Simulation ; Cost-Benefit Analysis ; *Food Supply ; *Health ; Humans ; *Methane/analysis ; Mortality, Premature ; *Ozone/analysis ; *Soot/analysis

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract. A bleached sulfate integrated pulp and paper mill producing printing and writing paper from mixed tropical hardwood and bamboo was studied. The mill uses a “conventional bleaching sequence,” C-E-H1-H2, with an average molecular chlorine consumption of 50 kg per ton of air-dried pulp (ADP). The content of polychlorinated dibenzofurans (PCDFs) and dibenzo-p-dioxins (PCDDs) in the bleaching filtrate in terms of the nordic toxicity equivalent (N-TEQ) was 33.5, 1.15, 0.56, and 0.014 pg/L for the E, C, H1, and H2 bleaching stages, respectively. The corresponding PCDFs and PCDDs loads in ng/t ADP were in the same ranking, i.e., 670, 69, 11.2, and 0.28, respectively. The congener and isomeric pattern of PCDFs and PCDDs of the bleaching filtrate and the bleached pulp was found to be typical for the chlorine bleaching plant effluent. The obtained dioxin load formed in the mill is in agreement with Western studies for the given multiple chlorine of 0.21–0.23. The load is, however, lower than reported discharges from Scandinavian mills using 1980s bleaching technologies, but substantially higher than the discharges from mills with modern bleaching technologies. Modifications in the bleaching plant to reduce molecular chlorine use are necessary to reduce dioxin formation.

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract Chemical analyses of organochlorine compounds in effluents, sediment, and biota samples were done for the Bai Bang Paper Company (BAPACO), a bleached kraft pulp and paper mill in Vietnam. High chlorine consumption in the bleaching process resulted in a high specific discharge of adsorbable organic halogens (AOX), 4.7 kg/ton of air dried pulp (ADP), and polychlorinated phenolic compounds (31 g/ton ADP) in the effluent. The extractable organochlorine content in the accumulated fiber sludge of the sedimentation tank (70–100 μg/g) was more than 100 times higher than the sediment from the receiving river. Chlorinated compounds including dioxins were detected at low levels in sediment and rice, crab, mollusc and fish samples. Significant amounts of the chlorinated persistent compounds are probably transported by the Red River to the river mouth and coastal area. Heavy metal content was high in sediment and mollusc samples from the receiving rice field and fish pond. There may be a possible risk for human intoxication of the metals through the aquatic food chain via the mollusc but not via the rice.

Electronic Resource