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Technical PublicationsEKONO's personnel are very active in technical associations and regularly present papers on the results of recent studies. The following abstracts summarize some of the recent publications that are available from EKONO. To request a copy of a publication, please e-mail us, providing us the name of the requested article and information where to send it (mail or fax). Links to abstracts on this page: Will Your Competitiveness Suffer from Increased Energy
Prices? "Will Your Competitiveness Suffer from Increased Energy Prices?", H. Mannisto, Advanced Tech Symposium '99, Montreal, PQ, Canada, November 29, 1999. Canadian pulp and paper mills consume as an average 30-50% more energy per ton of product than Finnish mills. Many factors, such as age and size of the mills, price of fuels and electricity, product mix and grade structure, etc., have led to this situation. With the increasing pressures for reduction of emissions and for sustainable operations, the fuel and power price differences between the countries are likely to level out. This may cause high energy users to suffer loss of competitiveness and search for ways to cut back the energy consumption and cost. "Effluent Manganese Limit Poses a Special Problem for a Bleached Kraft Pulp Mill on a Small River," E. Mannisto, G. Bourree, and G. Wohlgemuth, TAPPI 1999 Pulping Conference, Orlando, Florida, November 1999. The Weyerhaeuser Company, Grande Prairie is likely so far the only mill to have an effluent discharge mass limit for manganese (Mn). The manganese limit relates to the strict surface water quality criteria in Alberta and to the low flow of the receiving river. After river modeling Alberta Environment set the current limit as 65 kg/d of soluble Mn decrasing to 45 kg/d in 2002. To meet the future limit the mill needs to lower the discharge by around 36%. Extensive monitoring of manganese has been carried out during several years to understand the sources of Mn into various effluent streams, the behavior in the process and effluent treatment as well as the variability of manganese. The monitoring graphs are documented, together with an analysis of the influent variability and reasons thereof. Manganese in the ASB is fluctuating between soluble and particulate form in a way that is currently not understood. "Optimum Energy Efficiency - Comparison between North American and Nordic Pulp and Paper Mills," H. Mannisto and E. Mannisto, The Second Biennial Johan Gullichsen Colloquium, Espoo, Finland, September 1999. Energy efficiency of the pulp and paper industry has lately become of keen interest. The present market situation for pulp and paper products forces the industry to look for all possible and feasible cost savings opportunities. Energy may not be the biggest cost item in the mills. However, the savings in energy do not typically affect the production capabilities and product quality. The recent international agreements and efforts to reduce the emissions to the atmosphere are best met by reducing the use of fossil fuels. In addition to the cost and regulatory type of pressures some marketing issues, such as voluntary environmental labeling schemes, take the energy use into account. "Costs for Reducing Greenhouse Gas Emissions from the U.S. Forest Products Industry," B. Upton, R. Miner, and H. Mannisto, The Second Biennial Johan Gullichsen Colloquium, Espoo, Finland, September 1999. This study was undertaken to estimate the costs for reducing CO2 emissions from the U.S. forest products industry to levels 7% below estimated 1990 emissions, a target for the U.S. contained in the Kyoto Protocol. The pulp and paper sector of the industry has been studied by developing quasi-mill-specific energy balances for 90 mills accounting for approximately one-third of the pulp and paper produced in the U.S. Wood products facilities were handled differently due to limited data. One model facility was prepared for each type of wood product under study. Each facility's production was assumed to grow at 1.5% per year (an important assumption since costs have been found to be highly sensitive to growth rate). At this growth rate, and factoring in (a) continued improvements in energy efficiency and (b) the impacts of new environmental requirements, a 31% reduction from projected 2010 business-as-usual emissions would be needed to meet the Kyoto Protocol target. "The Impact of the Kyoto Agreement on Forest Industry in Canada," E. Mannisto and H. Mannisto, CPPA Annual Meeting and Exfor, Montreal, PQ, Canada, January 29, 1999. The Kyoto Agreement, which Canada among other countries has signed, commits most of the participating countries to reduce the emission of so-called greenhouse gases (GHG's) by 2010 to the 1990 level minus 6-8%. For Canada the target for 2010 is set at the 1990 level minus 6%. In this presentation it is assumed that any emitter of greenhouse gases has to implement necessary measures to reduce the emissions to the level as required by the Kyoto agreement. "Air and Effluent Quality Improvements Through Condensate Stripping," D. Taflin, B. Krzysik, and P. Winter, TAPPI 1997 Pulping Conference, San Francisco, CA, October, 1997. The Weyerhaeuser mill in Grande Prairie, Alberta was faced with increasingly stringent effluent BOD5 requirements in the early 1990s. In addition, they were experiencing difficulties with effluent toxicity and community odor complaints. Condensate stripping was investigated as a means to deal with all of these problems. As a basis for the process design, balances were developed for volatile BOD and TRS compounds in pulping and recovery, based on extensive sampling as well as theoretical considerations. Two main alternatives were developed: a Base Case, designed to treat a 3000 m3/d (550 USgpm) contaminated condensate stream, and an Alternative Case, which used further condensate volume reduction measures to treat 1700 m3/d (310 USgpm). Through heat integration with the evaporation plant, the net increase in steam demand was kept to a minimum. Modeling indicated that condensate stripping would reduce the discharge of volatile BOD by 88% and TRS by 98.5% in the Base Case, while in the Alternative Case the reductions would be 72% and 96%, respectively. Mill management decided to proceed with the Base Case in order to get maximum benefits and to position the mill for future effluent reduction and ultimate mill water system closure. The condensate stripping system was started up in September, 1993. It has met or exceeded all of its expectations: community odor complaints have dropped essentially to zero, sulfide-caused effluent toxicity has been eliminated, and the BOD in the raw mill effluent dropped by a surprising 12 kg/ADt; 6-8 kg/ADt had been expected based on volatile BOD balances. The rest has been attributed to improved liquor carryover control. "Feasibility of EPA's Advanced Technology Tiers," E. Mannisto, H. Mannisto, and K. Roos, TAPPI 1997 Environmental Conference and Exhibit, Minneapolis, MN, May 1997. An integral part of EPA's long-term goals, as declared in the proposed Cluster Rule, is an industry committed to continuous environmental improvement - an industry which aggressively pursues research to identify technologies that reduce and ultimately eliminate pollutant discharges. Implementation of pollution prevention technologies by moving towards closed-loop process operation, would increase reuse of recoverable materials and energy while reducing use of raw materials and generation of air emissions and hazardous and non-hazardous wastes. The proposed Cluster Rule establishes an incentive program consisting of three "Tiers" of BAT limitations beyond the baseline BAT. The most Advanced Technology Tier (III) limits AOX to 0.05 kg/kkg and the total flow of pulping and evaporator condensates and bleach plant wastewater to 5 m3/kkg.... "Why Energy Conservation?", H. Mannisto and E. Mannisto, TAPPI Engineering Conference, Nashville, TN, October 6-8, 1997. Energy conservation projects have traditionally been considered as cost reduction measures in the North American pulp and paper industry. Only a short time after the oil embargo in 1973, fuel availability was a major concern in addition to its cost. In some other areas, e.g., in Nordic countries, fuel has always been a scarce resource and energy conservation has been a way of life. "Current Environmental Performance of the Pulp and Paper Industry," M. Krogerus, E. Mannisto, and H. Mannisto, TAPPI Minimum Effluent Mills Symposium, Atlanta, GA, January 22-24, 1996. Environmental performance of the pulp and paper industry has been traditionally through regulation. The market forces, especially in Europe, are becoming dominant factors in the environmental issues. The study performed by the authors' organization addressed the current environmental performance and variabilities within the North American and Scandinavian pulp and paper industries. The study was based mainly on the performance data available from public sources. "Who Can Afford to Save Water?", G. Wohlgemuth, E. Mannisto, and H. Mannisto, TAPPI Minimum Effluent Mills Symposium, Atlanta, GA, January 22-24, 1996. The technical feasibility of low water use technologies has been proven in both pilot and mill scale. However, although technologies exist, the water and effluent flows are still fairly high in the pulp and paper industry. Obviously economic factors play a key role in the selection of technologies and water use levels. Especially for an existing mill, many technical factors determine the minimum required water usage level. This presentation addresses the economic and technological aspects that have to be taken into account when planning and implementing water conservation measures in an existing mill. The sample cases presented are from an existing bleached kraft mill. Water conservation in existing mills is seldom justifiable based on water price alone, but has to be motivated by other process and environmental benefits, such as reduction in energy costs, chemicals, fiber etc. "Technical and Economic Feasibility of a Low Effluent Bleached Kraft Mill," H. Mannisto, Envirotech Sympo '96, Vancouver, BC, Canada, April 1, 1996. The technical feasibility of low effluent concepts has been proven in both pilot and mill scale. Although technologies exist to lower water usage, water and effluent flows are still fairly high in the pulp and paper industry. The feasible water usage level depends on the technologies being used, especially in the pulp and bleaching processes. This level is determined by many factors, such as effluent temperature limitations, concentrations of impurities that can be tolerated in the processes, effluent toxicity and other parameters that are defined as maximum concentrations. In order to overcome the limitations, new mills in particular have set the goal to completely eliminate process effluents, such as bleach plant effluent. The mill cases that are reviewed here indicate that the industry is on the way to drastic reduction of effluent discharges. However, complete elimination of effluent from, e.g., a bleached kraft mill requires further research and mill scale testing before all aspects of the low effluent concepts can be considered proven technology. "How Green is the Future for Pulp and Paper?", H. Mannisto, E. Mannisto, and M. Krogerus, Papermaker 59:5, May, 1996. "Who Could be Eco-Labelled: An International Comparison of the Pulp and Paper Industry's Environmental Performance," L. Kaar, E. Mannisto, and M. Krogerus, ECOPAPERTECH Conference, Helsinki, Finland, June 6-9, 1995. This paper introduces the criteria applied in the European Union's environmental labelling scheme for paper products. These recently established guidelines can be divided into resource, energy and emission related parameters and are the compared with the actual environmental performance data from the North American and Scandinavian pulp and paper industries. The comparison reveals that it would presently be slightly more difficult for the North American producers to achieve the EU eco-label, primarily because of higher AOX discharges, less energy efficient production technologies and higher dependency on fossil fuels compared to their Scandinavian counterparts. |