scholarly journals Present trends and future prospects for poplar utilization in Alberta

1991 ◽  
Vol 67 (3) ◽  
pp. 271-274 ◽  
Author(s):  
W. J. Ondro

Between 1980 and 1990, poplar (mainly trembling aspen, Populus tremuloides Michx.) harvested on Crown and private lands in Alberta increased from 2.4 to 24.7% of the total harvest. In 1987-90, three oriented strandboard mills used more than 40% of the 1.4 million m3 of annual harvest of poplar from Crown and private lands. By the year 2000, the poplar harvest of five pulp and paper mills to be built between 1990 and 2000 is expected to reach about 8.5 million m3. By then, the pulp and paper industry will use about four-fifths of all poplar cut in Alberta.

1997 ◽  
Vol 35 (2-3) ◽  
pp. 321-328 ◽  
Author(s):  
P. Dell ◽  
R. Donald ◽  
J. McIntosh

New Zealand's primary environmental legislation, the Resource Management Act (RMA), was enacted in 1991. The RMA is effects based rather than activity based and is intended to promote the sustainable management of natural and physical resources. A number of New Zealand's pulp and paper mills are now coming under the permitting requirements of the RMA. The prime environmental concerns have been associated with the two kraft mills, and include dissolved oxygen, color, toxicity, nutrients and impacts on fisheries. This paper presents a case study of one of these mills and discusses the regulatory approach which is to be adopted under the constraints of the RMA.


2010 ◽  
Vol 62 (2) ◽  
pp. 387-393 ◽  
Author(s):  
H. Kyllönen ◽  
J. Lehto ◽  
P. Pirkonen ◽  
A. Grönroos ◽  
H. Pakkanen ◽  
...  

Large amounts of wet sludge are produced annually in municipal and industrial wastewater treatment. Already in pulp and paper industry, more than ten million tons of primary sludge, waste activated sludge, and de-inking sludge is generated. Waste activated sludge contains large quantities of bound water, which is difficult to dewater. Low water content would be a matter of high calorific value in incineration but it also has effects on the volume and the quality of the matter to be handled in sludge disposal. In this research waste activated sludges from different pulp and paper mills were chemically characterised and dewatered. Correlations of chemical composition and dewatering properties were determined using multivariate analysis. Chemical characterisation included basic sludge analysis, elementary analysis and analysis of wood-based components, such as hemicelluloses and lignin-derived material. Dewatering properties were determined using measurements of dry solids content, flux and flocculant dosage. The effects of different variables varied according to the response concerned. The variables which were significant regarding cake DS increase in filtration or centrifugation and flocculant dosage needed in filtration were different from those which were significant regarding flux.


2010 ◽  
Vol 62 (10) ◽  
pp. 2364-2371 ◽  
Author(s):  
M. Sandberg

More than 50% of the electrical power needed to treat pulp and paper industry effluents is used for aeration in biological treatment stages. A large share of the oxygen that passes through the wastewater is not consumed and will be found in the off-gas. Energy can be saved by aerating under conditions where the oxygen transfer is most efficient, for example at low concentrations of dissolved oxygen Consider the sludge as an energy source; electricity can be saved by avoiding sludge reduction through prolonged aeration. High oxygen transfer efficiency can be retained by using the oxygen consumption of biosolids. Quantified savings in the form of needed volumes of air while still achieving sufficient COD reduction are presented. The tests have been made in a bubble column with pulp mill process water and sludge from a biological treatment plant. These were supplemented with case studies at three pulp and paper mills.


1997 ◽  
Vol 35 (2-3) ◽  
pp. 117-122 ◽  
Author(s):  
Thomas Welander ◽  
Anders Löfqvist ◽  
Anders Selmer

The possibility of improving the efficiency of aerated lagoons treating pulp and paper industry effluents by introducing a support material for microbial growth was studied on a pilot plant scale. Two 20 m3 pilot plants were operated for approximately one year in parallel with full-scale aerated lagoons at two Swedish pulp and paper mills. A support material specifically developed for application in aerated lagoons was installed in the pilot plants. A considerably higher treatment efficiency was obtained in the pilot plants than in the full-scale lagoons. While 30-40% of the COD was removed in the full-scale lagoons, a COD-removal of 60-70% was achieved in the pilot plants. Phosphorus, an important discharge parameter at both mills, was removed to 60-70%, while the removal in the full scale lagoons was only 0-10%. The suspended solids in the treated effluent after clarification was around 20 mg/l.


1999 ◽  
Vol 75 (2) ◽  
pp. 247-255 ◽  
Author(s):  
Dinesh Mohta ◽  
D. N. Roy

Forests play a vital role in the social, economic, and environmental development of any country. Paper, composed principally of wood fiber, is an essential commodity in promoting literacy, communication, documentation, and packaging. However, there is much concern about the world's forests being over-utilized. This has led to serious repercussions, not only to humanity, but also to the earth's biodiversity as a whole. It is now time that forests be used in a more responsible and ethical manner. Because of reduced forest area, increasing pulpwood costs, and an increasing demand for pulp and paper products, it might be expected that the focus would shift to high yield pulping processes or to the use of cellulosic non-wood raw materials. Non-woods are available in good supply all over the world, but are currently under-utilized. It is estimated that replacing 5–10% of wood pulp with non-wood pulp would have an important impact on the conservation of forests and the environment. This replacement of wood pulp by non-wood pulp could be environmentally and economically acceptable even in developed countries. By doing so, pulp and paper mills would have a lead role in reducing their dependency on forests for fiber. This determination and commitment would enhance the long-term sustainability of forests and the pulp and paper industry. Above all, it would be a sustainable step towards "our common future." Key words: forest, sustainable development, fiber supply, pulp and paper, non-woods


2007 ◽  
Vol 55 (6) ◽  
pp. 117-123 ◽  
Author(s):  
C.R. Oliveira ◽  
C.M. Silva ◽  
A.F. Milanez

In the pulp and paper industry, the water use minimization is a constant target. One way to reduce water use is to recycle the effluent in a closed-cycle concept. In paper mills, the main source of liquid effluent is the so-called whitewater, which is the excess water, originated from pulp stock dewatering and other fibre contaminated water. This research studied the reuse of paper mill whitewater after membrane ultrafiltration (UF) in the paper machine and in the pulp bleach plant of an integrated mill. Contaminant removal and flux behaviour of the UF system were evaluated. The treatment by ultrafiltration was technically feasible and the treated whitewater had good potential to be reused in some processes in the paper machine. The reuse of ultrafiltered whitewater in the bleaching plant was not recommended because of the high level of soluble calcium present in this stream. Therefore, a combined treatment of the whitewater using the principle of precipitation and ultrafiltration was proposed showing good results and enabling the use of the treated whitewater in the bleach plant.


2012 ◽  
Vol 26 ◽  
pp. 41-46
Author(s):  
MMA Quader

Pulp and paper sector in Bangladesh is used to get less importance in comparison with that of other sectors related to socioeconomic development of the country. KPML, the oldest integrated pulp and paper industry in Bangladesh built in the early fifties of last century is still in operation. Recently, almost hundred paper mills are erected and most of those are in operation and producing varieties of papers. This article deals with the problems in operating the mills and makes suggestions to improve its operation and productivity. The major challenges in paper sector and the scope of development is discussed. DOI: http://dx.doi.org/10.3329/jce.v26i1.10181 JCE 2011; 26(1): 41-46


1996 ◽  
Vol 1 (4) ◽  
pp. 379-401 ◽  
Author(s):  
David A. Sonnenfeld

This paper analyzes how a key conflict in Australia's pulp and paper industry became generalized to other sites through environmental action, government regulation, and industry initiative. From 1987–91, Australians debated construction of a new, world-class, export-oriented pulp mill in Tasmania. Rural residents, fishermen, and environmentalists, allied with the Australian Labor Party, succeeded in scuttling the project. Subsequently, the national government launched a major research program, state governments tightened regulations, and industry reduced elemental chlorine use. Any new mills constructed in Australia today would be among the cleanest in the world. This paper is part of a larger, comparative study of technological innovation in the pulp and paper industries of Australia, Indonesia, Malaysia, and Thailand. The author interviewed industry officials, government regulators, research scientists, and environmentalists; visited pulp and paper mills; attended technical conferences; and conducted archival work in these countries during a 12-month period.


2001 ◽  
Vol 123 (4) ◽  
pp. 734-740 ◽  
Author(s):  
K. Maunsbach ◽  
A. Isaksson ◽  
J. Yan ◽  
G. Svedberg ◽  
L. Eidensten

The pulp and paper industry handles large amounts of energy and today produces the steam needed for the process and some of the required electricity. Several studies have shown that black liquor gasification and combined cycles increase the power production significantly compared to the traditional processes used today. It is of interest to investigate the performance when advanced gas turbines are integrated with next-generation pulp and paper mills. The present study focused on comparing the combined cycle with the integration of advanced gas turbines such as steam injected gas turbine (STIG) and evaporative gas turbine (EvGT) in pulp and paper mills. Two categories of simulations have been performed: (1) comparison of gasification of both black liquor and biomass connected to either a combined cycle or steam injected gas turbine with a heat recovery steam generator; (2) externally fired gas turbine in combination with the traditional recovery boiler. The energy demand of the pulp and paper mills is satisfied in all cases and the possibility to deliver a power surplus for external use is verified. The study investigates new system combinations of applications for advanced gas turbines.


Sign in / Sign up

Export Citation Format

Share Document