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Van Deusen P.C.,NCASI | Heath L.S.,U.S. Department of Agriculture
Forest Ecology and Management | Year: 2010

Weighted estimation methods for analysis of mapped plot forest inventory data are discussed. The appropriate weighting scheme can vary depending on the type of analysis and graphical display. Both statistical issues and user expectations need to be considered in these methods. A weighting scheme is proposed that balances statistical considerations and the logical expectations of users. The methods described here are being used in an online forest carbon estimation tool. Example applications are presented to demonstrate the methods. © 2010 Elsevier B.V.

Amor M.B.,Ecole Polytechnique de Montréal | Pineau P.-O.,HEC Montréal | Gaudreault C.,NCASI | Samson R.,Ecole Polytechnique de Montréal
Energy Policy | Year: 2011

Worldwide electricity sector reforms open up electricity markets and increase trades. This has environmental consequences as exports and imports either increase or decrease local production and consequently greenhouse gas (GHG) emissions. This paper's objective is to illustrate the importance of electricity trade's impact on GHG emissions by providing an estimate of the net GHG emissions resulting from these trades. To achieve this objective, Quebec hourly electricity exchanges with adjacent jurisdictions were examined over the 2006-2008 period. In order to associate a specific GHG emission quantity to electricity trades, hourly marginal electricity production technologies were identified and validated using the Ontario hourly output per power plant and information released in the Quebec adjacent system operator reports. It is estimated that over three years, imports into Quebec were responsible for 7.7. Mt of GHG, while Quebec hydropower exports avoided 28.3. Mt of GHG emissions. Hence, the net result is 20.6. Mt of avoided emissions over 2006-2008, or about 7. Mt per year, which corresponds to more than 8% of the Quebec yearly GHG emissions. When GHG emissions from all life cycle stages (resource extraction to end-of-life) are accounted for, the net avoided GHG emissions increase by 35%, to 27.9. Mt. © 2011 Elsevier Ltd.

In aquatic systems, total ammonia concentration is comprised of ionized (NH4 +) and un-ionized (NH3) forms, with NH 3 being more toxic to fish than NH4 +. The relative concentration of these two forms depends on water temperature and pH, with the relative concentration of NH3 increasing as temperature and pH increase. This has implications for regulatory compliance because pH shifts during bioassay testing may indicate effluent toxicity when, in fact, a pH-associated increase in the fraction of un-ionized ammonia, and not the presence of some other toxic compound(s), was responsible for the bioassay response. Environment Canada does not currently allow the use of pH stabilization techniques during the acute lethality testing of pulp and paper mill effluents. This restriction is based on EC's concern that the use of such techniques could mask the toxicity of certain constituents of these effluents. The available literature, however, suggests that pH stabilization is necessary (a) to avoid inadvertent toxicity resulting from the formation of artefact un-ionized ammonia, and (b) to reduce the risk of masking the toxicity of compounds whose acute effects in fish decrease as a result of a pH change. This report summarizes published research addressing the relationship between pH and the acute lethality of substances typically found in pulp and paper mill effluents. Results from this review suggest that the acute toxicity of substances like resin acids, hydrogen sulphide, polychlorinated phenolics, and certain metals (e.g., chromium, lead, mercury, copper, and zinc) may be masked if pH is not stabilized during acute bioassay tests of pulp and paper mill effluents.

van Deusen P.C.,NCASI
Canadian Journal of Forest Research | Year: 2010

Managing the forest to store carbon is a relatively new concept. Various regional greenhouse gas initiatives and new Federal legislation are providing financial incentives for forest owners to manage for carbon in addition to other forest products. These incentives are intended for landowners who engage in activities that go beyond business as usual practices. Managing for carbon will likely involve foregoing other investment alternatives and increasing rotation lengths. The analysis approach demonstrated here provides a relatively simple method for an owner to compare traditional forest management and regular harvests with letting the trees grow to accumulate more carbon in the forest. Several financial decision statistics are considered and demonstrated with examples. A derivative of land expectation value, called rotation equivalent value, is shown to be a useful decision tool for comparing carbon storage with other management options having different rotation lengths.

One important characteristic of forest products is that several co-products (products that are produced as the result of the same shared process) can be manufactured in the same value chain. Very often, the objective of a life cycle assessment (LCA) or carbon footprint study is to describe the environmental attributes of only one of these co-products. (Note: While LCA studies generally cover several different potential impact indicators, carbon footprint studies focus only on the global warming indicator.) In that situation, it is necessary to decide how to partition, or to allocate, the environmental loads in the value chain between the different co-products. This report describes, discusses, and illustrates, with forest product examples, the most common approaches for co-product allocation and proposes a step-by-step approach to address complex allocation situations at pulp and paper mills (i.e., how to allocate pulp and paper mill environmental loads between the different paper grades, chemicals and energy produced). It is shown that, in some cases, the choice of allocation method can have significant implications for the results.

In this document, the allocation methods for open-loop recycling most frequently used in pulp and paper case studies or presented as options in the ISO standards on life cycle assessment (LCA) are presented, illustrated, discussed and compared. It is shown that the choice of one allocation procedure over another can have a significant effect on the results of an LCA. In particular, the ISO standards on LCA require that sensitivity analyses be performed when several methods seem applicable. In part because of this, LCA may not be useful for obtaining unambiguous conclusions if the objective of the LCA is to compare virgin and recycled paper. When selecting an allocation method for recycling, the following should be kept in mind: the method should be consistent with the objective of the study; the set of values inherent to the selection of the method should be transparent; the selected method should preserve mass and energy balances (with the exception of the closed-loop procedure); and a similar allocation method should be applied to both the inflows and outflows of recovered material in the system boundary.

Malmberg B.,NCASI
2011 TAPPI PEERS Conference | Year: 2011

• US mills save over 54 billion cubic meters of water annually by using current water recycling practices. • If all US pulp and paper production was derived from modern mills equipped with best commercially available technology for water reduction about 5% of additional water savings would be realized. • Small difference in water savings between current practice and hypothetical low use cases indicates a high degree of water recycle within the industry.

A 40 year projection of potential carbon sequestration is based on USDA Forest Service Forest Inventory and Analysis (FIA) data from the state of Georgia. The objective is to compare carbon sequestration under a sustainable management strategy versus a preservation strategy. FIA plots are projected ahead in time with hotdeck matching. This matches each subject plot with another plot from the database that represents the subject plot at a future time. The matched plot sequences are used to provide input data to a harvest scheduling program to generate a management strategy for the state. The sequestration from the management strategy is compared with a preservation strategy that involves no harvesting. Harvested wood is assumed to go into products with various half life decay rates. Carbon sequestration is increased as increasing proportions go into wood for energy, which is treated like a product with an infinite half life. Therefore, the harvested carbon does not return immediately to the atmosphere. Public land and land close to cities is assumed to be unavailable, and all other private land is assumed to be accessible. The results are presented as gigatonnes of CO2 equivalent to make them directly comparable to US annual carbon emissions. The conclusion is that forest management will sequester more above-ground carbon than preservation over a 40 year period if the wood is used for products with an average half life greater than 5 years. © 2010 Elsevier Ltd.

Air and Waste Management Association - Air Quality Measurement Methods and Technology Conference 2012 | Year: 2012

This study focused on methods for measuring VOCs and techniques for calculating VOC mass emissions. Measurement methodology centered on resolving known issues with testing sources (Graph Presented) at wood products mills. While NCASI believes that the targeted measurement issues were resolved, the majority of sources tested for this study were not fully speciated. This indicates that either (1) other parameters are impacting the collection and measurement of organic compounds requiring additional sampling methods or (2) there may be a limit to the precision and accuracy that can be achieved for measuring VOCs from certain emission sources. Measuring VOC emissions can be a very complex task because source gas characteristics are variable, unknown compounds may be present, and multiple measurement methods are generally required to capture a wide variety of organic compounds. For complex gas streams where full VOC speciation is not achieved, the determination of VOC mass emission rates will have an estimated component. Since true emission values would be unknown, it is difficult to tell whether one estimating technique is better than another. EPA and the wood products industry have agreed to improve the estimation of VOC mass emissions by phasing in a new reporting protocol, OTM 26, for certain regulatory purposes that have traditionally been based on Method 25A. This study has made an attempt to evaluate the results yielded by OTM 26 for a variety of emission sources and, as expected, OTM 26 results are greater than Method 25A results. The need to improve the estimation of VOC mass emissions beyond OTM 26 was also evaluated in this study. NCASI used a Study Benchmark Estimate to compare results from Method 25A, OTM 26, Modified M25A, and Modified OTM 26.13 For the wood products sources tested, Method 25A differed by -32%, OTM 26 differed by -19%, Modified M25A differed by -16%, and Modified OTM 26 differed by -9%.14 The comparison of the various calculation techniques indicates that source gas characteristics have the most impact on determining adequate VOC mass estimations. Further details on source specific evaluations for the data provided in this document are available to NCASI members in Technical Bulletin No. 991, Characterization, measurement, and reporting of volatile organic compounds emitted from southern pine wood products sources.

Gaudreault C.,National Council for Air and Stream Improvement Inc. | Malmberg B.,NCASI | Upton B.,NCASI | Miner R.,NCASI
Biomass and Bioenergy | Year: 2012

The life cycle greenhouse gas (GHG) and fossil fuel benefits of black liquor recovery are analyzed. These benefits are due to the production of energy that can be used in the pulping process or sold, and the recovery of the pulping chemicals that would otherwise need to be produced from other resources. The fossil GHG emissions and non-renewable energy consumption of using black liquor in the kraft recovery system are approximately 90% lower than those for a comparable fossil fuel-based system. Across all scenarios, the systems relying on black liquor solids achieve a median reduction of approximately 140 kg CO 2 eq./GJ of energy produced, compared to the systems relying on fossil fuels to provide the same energy and pulping chemical production functions. The benefits attributable to the recovery of pulping chemicals vary from 44% to 75% of the total benefit. Applied to the total production of kraft pulp in the U.S., the avoided emissions are equivalent to the total Scopes 1 and 2 emissions from the entire U.S. forest products industry. These results do not depend on the accounting method for biogenic carbon (because biogenic CO 2 emissions are the same for the systems compared) and the results are valid across a range of assumptions about the displaced fossil fuel, the GHG-intensity of the electricity grid, the fossil fuels used in the lime kiln, and the level of cogeneration at pulp and paper mills. The benefits occur without affecting the amount of wood harvested or the amount of chemical pulp produced. © 2012 Elsevier Ltd.

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