Application of the paleolimnological method to assess metal contaminant distribution (As, Cu, Pb, Zn) in pulp mill stabilization basin sediments, Nova Scotia, Canada

Author(s):  
Kirklyn B. Davidson ◽  
Baillie E. J. Holmes ◽  
Ian S. Spooner ◽  
Dewey W. Dunnington ◽  
Tony R. Walker ◽  
...  
Author(s):  
Charles T. Schafer

During the 20th century, contamination of marine environments by Canadian pulp and paper mill effluent (PPE) resulted in the imposition of federal government regulations in 1971 that were revised and strengthened in 1992. This report reviews seafloor sediment features for three marine settings (intertidal, subtidal and prodelta) arising from 20th century PPE discharges from four pulp and paper mills, one located near New Richmond, Quebec, and three situated along the lower reaches of the Saguenay River, Quebec. The four mills began operations between 1965 and the early 1900’s. Observations of their proximal and distal sediment and Foraminifera characteristics in relation to PPE discharge outfalls offer guidance for the remediation of potentially toxic, multi-decadal waste accumulations in several lagoons of Boat Harbour, Nova Scotia. Seafloor environmental data discussed for a fifth mill’s subtidal outfall, located on the eastern shore of Canso Strait, may be particularly germane for selecting the site and baseline environmental survey criteria for a new PPE submarine outfall that has been proposed (presently rejected) by Northern Pulp Company for the Caribou Harbour area of the Northumberland Strait coast, in the event that the currently closed mill is permitted to be reactivated in the future. Keywords: effluent, environmental effects, organic matter, pulp mill waste, sediments


2009 ◽  
Author(s):  
Marc W. Patry ◽  
Veronica Stinson ◽  
Steven M. Smith

1894 ◽  
Vol 38 (984supp) ◽  
pp. 15724-15725
Author(s):  
Hugh Fletcher
Keyword(s):  

TAPPI Journal ◽  
2013 ◽  
Vol 12 (6) ◽  
pp. 9-15 ◽  
Author(s):  
TOMI HIETANEN ◽  
JUHA TAMPER ◽  
KAJ BACKFOLK

The use of a new, technical, high-purity magnesium hydroxide-based peroxide bleaching additive was evaluated in full mill-scale trial runs on two target brightness levels. Trial runs were conducted at a Finnish paper mill using Norwegian spruce (Picea abies) as the raw material in a conventional pressurized groundwood process, which includes a high-consistency peroxide bleaching stage. On high brightness grades, the use of sodium-based additives cause high environmental load from the peroxide bleaching stage. One proposed solution to this is to replace all or part of the sodium hydroxide with a weaker alkali, such as magnesium hydroxide. The replacement of traditional bleaching additives was carried out stepwise, ranging from 0% to 100%. Sodium silicate was dosed in proportion to sodium hydroxide, but with a minimum dose of 0.5% by weight on dry pulp. The environmental effluent load from bleaching of both low and high brightness pulps was significantly reduced. We observed a 35% to 48% reduction in total organic carbon (TOC), 37% to 40% reduction in chemical oxygen demand (COD), and 34% to 60% reduction in biological oxygen demand (BOD7) in the bleaching effluent. At the same time, the target brightness was attained with all replacement ratios. No interference from transition metal ions in the process was observed. The paper quality and paper machine runnability remained good during the trial. These benefits, in addition to the possibility of increasing production capacity, encourage the implementation of the magnesium hydroxide-based bleaching concept.


Sign in / Sign up

Export Citation Format

Share Document