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Kyoto Protocol : impact on wood products industry

https://library.fpinnovations.ca/en/permalink/fpipub39288
Author
Barry, A.
Date
March 2010
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barry, A.
Contributor
Canadian Forest Service.
Date
March 2010
Material Type
Research report
Physical Description
11 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Pollution
Air pollution
Air
Series Number
Canadian Forest Service No. 15
E-4621
Location
Québec, Québec
Language
English
Abstract
Canada has recently published our national Kyoto Protocol final GHG reduction target and fixed at 17% reduction for 2020 based on year 2005 after Potsdam UN conference. In order to meet our national target, the federal government has put in place many plans to assist different industrial sectors in reducing their GHG emissions resulting from their activities. One of the last plans set by the Government called “Green Plan” for the Pulp and Paper sector provides incentives to convert the black liquor into green energy or invest in more efficient technology to reduce energy consumption or produce greener energy and consequently reduce or eliminate the fossil fuel energy, which is related to GHG emission. Up to 24 pulp mills have been qualified to submit projects under the program. The Plan has been very well accepted and contributes to maintain our competitiveness vis-à-vis US mills that have benefitted from a similar program by simply optimizing their existing burners. Proven technologies are now available for better conversion of the black liquor into energy and/or chemicals through gasification and mills should certainly consider these options. Black Liquor gasification can be used to produce methanol, dimethyl ester (DME) or Fisher-Tropsch Siesel (FTD). This technology also has strong potential synergies with power generation and could be an option for the pulp and paper mills generate additional revenues while providing a contribution to the production of substitutes for the fossil fuels used in transportation. Total greenhouse gas emissions in Canada were estimated at in 721 megatons of carbon dioxide equivalent (Mt of CO2 eq) in 2006 and 80% of these GHG are emitted from the production and transportion these fuels. Hence, conversion of biomass & black liquor by gasification could help in reducing emissions from transportation fuels and also potentially reduce indirect emissions by increasing power generation from the pulp mills. The forest sector is known as having a huge potential for GHG reduction and offsets, investing more in this sector as proposed by the federal Green Plan, could assist other sectors in meeting their GHG target through offsets generated by the wood industry sector.
Air pollution
Documents
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Development of an improved method for analysis of panels with low formaldehyde emission (Part B)

https://library.fpinnovations.ca/en/permalink/fpipub39297
Author
Dechamplain, F.
Date
March 2010
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Dechamplain, F.
Contributor
Canadian Forest Service
Date
March 2010
Material Type
Research report
Physical Description
13 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Pollution
Panels
Air pollution
Air
Series Number
Canadian Forest Service No. 20
201000329
Location
Québec, Québec
Language
English
Abstract
In April 2008, the State of California adopted an airborne toxic control measure (ATCM) to reduce formaldehyde emissions from composite wood products, proposed by the California Air Resources Board (CARB), part of the California Environmental Protection Agency. Phase 1 started in January 2009, and at the end of the implementation, in July 2012, formaldehyde emission limits will range between 0.05 and 0.13 ppm, depending on the type of products, based on the ASTM E 1333 Large Chamber Method. These new limits are in the order of the limits of detection of the current analytical methods presently used, and rendered the chromotropic acid reaction, on which the ASTM E 1333 is based, with a limit of detection of 0.01 ppm less precise. The use of Near Infrared technology was investigated in 2009/2010. This analytical technique was not initially considered to be sensitive enough to measure formaldehyde emissions at very low levels. Recent developments in the broadband sources of near infrared radiation available and the type of detectors used have contributed in recent years to improve spectral stability and sensitivity. Some instruments have recently been tested in Europe and equipment suppliers claim that these systems can be used for online monitoring of formaldehyde emissions. This analytical technique is not recognized at this time by Canadian and US regulatory authorities and more testing was required to demonstrate the system’s reliability. Commercial products with very low free formaldehyde have been tested in 2009 with NIR sensors and results have been correlated with the ASTM E 1333 Large Chamber test results. At least one Canadian panel manufacturer has already expressed interest in running a mill trial. Results will be presented to regulatory authorities.
Air pollution
Formaldehyde
Panels
Documents
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Kyoto protocol impact on wood products industry

https://library.fpinnovations.ca/en/permalink/fpipub39221
Author
Barry, A.
Date
July 2009
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barry, A.
Date
July 2009
Material Type
Research report
Physical Description
9 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Pollution
Air pollution
Air
Series Number
Canadian Forest Service No. 15
4005
Location
Québec, Québec
Language
English
Abstract
Air pollution
Documents
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Development of an improved method for analysis of panels with low formaldehyde emission

https://library.fpinnovations.ca/en/permalink/fpipub39223
Author
Dechamplain, F.
Date
March 2009
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Dechamplain, F.
Contributor
Canadian Forest Service
Date
March 2009
Material Type
Research report
Physical Description
28 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Pollution
Panels
Air pollution
Air
Series Number
Canadian Forest Service No. 20
5763
Location
Québec, Québec
Language
English
Abstract
In April 2008, the State of California adopted an airborne toxic control measure (ATCM) to reduce formaldehyde emissions from composite wood products, proposed by the California Air Resources Board (CARB), part of the California Environmental Protection Agency. Phase 1 started in January 2009, and at the end of the implementation, in July 2012, formaldehyde emission limits will range between 0.05 and 0.13 ppm, depending on the type of products, based on the ASTM E 1333 Large Chamber Method. These new limits are in the order of the limits of detection of the current analytical methods presently used, and rendered the chromotropic acid reaction, on which the ASTM E 1333 is based, with a limit of detection of 0.01 ppm less precise. An alternative method to determine formaldehyde concentration in air has been developed to be used as part of the ASTM E1333 Large Chamber Method. 60 L of air are sampled through an impinger containing an acetylacetone-ammonia solution. The solution is then heated, and analyzed by fluorimetry using a Turner Quantech filter fluorometer equipped with a NB430 excitation filter and a SC500 emission filter. The test method is inexpensive, easy to use, compatible with the Large Chamber, Perforator and Desiccator Methods, and is very sensitive. The minimum detection limit (MDL) and the limit of quantification (LOQ) of this analytical method are 0.0004 and 0.0013 ppm, respectively.
Air pollution
Formaldehyde
Panels
Documents
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Review of technologies to lower formaldehyde emissions from composite wood panels

https://library.fpinnovations.ca/en/permalink/fpipub5628
Author
Feng, Martin
He, G.
Date
June 2009
Edition
37963
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Feng, Martin
He, G.
Date
June 2009
Edition
37963
Material Type
Research report
Physical Description
23 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Toxicity
Pollution
Gluing
Air pollution
Air
Series Number
General Revenue Report Project No. 5726
W-2674
Location
Vancouver, British Columbia
Language
English
Abstract
This report examines various aspects of the formaldehyde emission issue facing the wood composite panel industry in order to help Forintek member companies best navigate this extremely important but increasingly complex problem. It is a state-of-the-art review of fundamentals associated with the formaldehyde emission problem, various standards and regulations, and known technologies for the reduction of formaldehyde emissions. It has distilled and concentrated a vast amount of information based on the literature review, international conferences, known industrial practices and experiences of the authors. Due to its hydrolytic instability, urea-formaldehyde (UF) adhesive is the main source of formaldehyde emissions from UF-bonded particleboard, medium density fiberboard (MDF), high density fiberboard (HDF) and hardwood plywood through out their service life. There are various technologies available to reduce formaldehyde emission. These are: 1. Chemical modifications of UF resin (lower formaldehyde/urea (F/U) molar ratios, improved resin synthesis procedures, condensed with small amounts of melamine, use of formaldehyde scavengers, use of catalysts/hardeners, cross-linked with methylene diphenyl diisocyanate (MDI) or various combinations of these); 2. Panel post-treatments (anhydrous ammonia treatment, panel overlay, coating, etc.); 3. Manipulation of production process conditions; 4. Using alternative adhesives to replace UF resin; 5. Making binderless panel products. Some of these technologies can meet the challenges of the most stringent regulations, but likely at higher cost or lower productivity. The most promising options are using commercially available alternative wood adhesives (phenol-formaldehyde (PF), MDI, melamine-formaldehyde (MF), polyvinyl acetate (PVA) or soy) to replace UF. Depending on end use and target market, using ultra-low formaldehyde emitting UF or urea-melamine-formaldehyde/melamine-urea-formaldehyde (UMF/MUF) in combination with an effective catalyst/hardener and/or formaldehyde scavenger can also be a practical option.
Air pollution - Sources - Gluing
Formaldehyde Emissions - Control
Formaldehyde - Toxicity
Documents
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Using urea to reduce formaldehyde, acrolein and VOC emissions from OSB pressing.

https://library.fpinnovations.ca/en/permalink/fpipub5620
Author
Feng, Martin
Date
January 2008
Edition
37870
Material Type
Pamphlet
Field
Wood Manufacturing & Digitalization
Author
Feng, Martin
Date
January 2008
Edition
37870
Material Type
Pamphlet
Physical Description
7 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Pollution
Materials
Air pollution
Air
Series Number
W-2497
Language
English
Abstract
This research work involved the production of aspen OSB panels in a pilot plant using three types of commercial adhesive systems respectively as a wood binder (PF, PF/MDI and MDI). It was demonstrated that spraying urea aqueous solution to dry wood strands at 0.2% and 0.5% urea loading rates (urea solids on a dry wood weight basis) can effectively reduce the emissions of formaldehyde, acrolein and some other volatile organic compounds from OSB pressing without adversely affecting the board properties regardless which type of adhesive is used. The side-effect of the urea addition was the dramatic increase of press emission of nitrogen compounds, most likely due to the slow decomposition of urea to ammonia at high press temperatures. This approach may also be effectively and economically applied to lowering formaldehyde, acrolein and VOC emissions from OSB dryer and the side-effect of increased nitrogen compounds emission could be less due to lower wood temperatures inside the OSB dryer than those inside the OSB press. It was also demonstrated that using MDI adhesive to partially or completely replace PF adhesive can lower formaldehyde, phenol and total VOC emissions from OSB pressing. Under the test conditions of this work and without urea addition, the MDI-bonded aspen OSB panels emitted about 87% less formaldehyde, 80% less phenol and 25% less water-soluble VOC than the PF-bonded aspen OSB panels. The PF/MDI-bonded aspen OSB panels emitted about 61% less formaldehyde, 41% less phenol and 11% less water-soluble VOC than the same PF-bonded panels. However, the MDI-bonded panels produced 65% higher water-insoluble VOC than that of the PF-bonded panels although the water-insoluble VOC accounted for less than 3% of the total VOC emitted from the MDI-bonded panels.
Composite materials - Manufacture
Formaldehyde
Air pollution
Air pollution - Sources
Documents
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Impact of Kyoto protocol on composite panel industries

https://library.fpinnovations.ca/en/permalink/fpipub39104
Author
Barry, A.
Date
March 2008
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barry, A.
Date
March 2008
Material Type
Research report
Physical Description
73 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Regulations
Pollution
Canada
Air pollution
Air
Series Number
Canadian Forest Service No. 15
4005
Location
Québec, Québec
Language
English
Abstract
One can summarize the work conducted under the Kyoto protocol by extracting some paragraphs from the Montreal climate conference press release. Under the Kyoto Protocol, which entered into force 16 February 2005, more than 30 industrialized countries are bound by specific and legally binding emission reduction targets. As a first step, these cover the period 2008-2012. The Kyoto Protocol is now fully operational. The adoption of the Marrakesh accords formally launches emissions trading and the other two mechanisms under the Kyoto Protocol. Carbon has now a market value. Under the clean development mechanism, investing in projects that provide sustainable development and reduce emissions makes sound business sense. The Joint Implementation (JI) adopted by the parties is one of the mechanisms which allow developed countries to invest in other developed countries and thereby earn carbon allowances which they can use to meet their emission reduction commitments. In addition to this, the clean development mechanism allows industrialized countries to invest in sustainable development projects in developing countries and thereby earn carbon allowances. “With these decisions in place, we now have the infrastructure to move ahead with the implementation of the Kyoto protocol” said Richard Kinley, head of the United Nations Climate Change conference. It sets solid basis for future steps to bring emissions down he added. All Kyoto Protocol Parties, including Canada, are now moving ahead to meet their GHG emission reduction commitments. In the past few years, Canada has developed and set strategies to meet our commitments. However, Canada has since changed for a new conservative government and a new strategy has been published first in April and the proposed greenhouse gas regulations are expected to be published in the Canada Gazette later this year, and the regulations finalized in 2009 to come into force as planned on January 1, 2010 according to the minister. During this fiscal year two Canadian provinces took important steps in regards to climate change by adopting regulations to reduce their respective GHG emissions. The province of BC has published its own green house gas reduction targets through the Bill 44 in which the province has set reduction targets by 2020 for 33% and 80% by 2050 relative to 2007 emissions levels for both. In 2007 the Quebec government announced the first carbon tax in Canada to Oil companies to pay a new energy tax of 0.8 cents a litre for gasoline distributed in the province and 0.938 cents for diesel fuel. The province has also adopted California’s greenhouse gas standards for new light-duty vehicles.
Composites
Air pollution - Canada - Laws and regulations
Carbon
Documents
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Optimisation de la vitesse de l'air dans les séchoirs

https://library.fpinnovations.ca/en/permalink/fpipub39122
Author
Lavoie, Vincent
Normand, D.
Date
March 2008
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Lavoie, Vincent
Normand, D.
Date
March 2008
Material Type
Research report
Physical Description
19 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Optimization
Drying
Air
Series Number
Projet General Revenue no 5364
5364
Location
Québec, Québec
Language
French
Abstract
Optimization
Drying
Air flow
Documents
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Effectiveness of barriers to minimize VOC emissions, including formaldehyde

https://library.fpinnovations.ca/en/permalink/fpipub37914
Author
Barry, A.
Date
April 2008
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barry, A.
Date
April 2008
Material Type
Research report
Physical Description
4 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Toxicity
Pollution control
Pollution
Air pollution
Air
Series Number
RDS 08-06
W-2581
Location
Québec, Québec
Language
English
Abstract
In this study, various finishing materials used by primary and secondary particleboard and medium-density fibreboard (MDF) manufacturers were subjected to emissions testing in order to determine the most efficient barriers to eliminate (or at least reduce) formaldehyde and other volatile organic compounds (VOC) emissions from MDF and particleboard products.
Air pollution - Control
Formaldehyde - Toxicity
Documents
Less detail

Biological method to pre-dry lumber with wetwood

https://library.fpinnovations.ca/en/permalink/fpipub39015
Author
Yang, D.-Q.
Date
March 2007
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Date
March 2007
Material Type
Research report
Physical Description
62 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Yeasts
Wetwoods
Seasoning
Bacteria
Series Number
General Revenue Project No. 4030
4030
Location
Québec, Québec
Language
English
Abstract
Wetwood, or water pocket, has higher moisture content (MC) and lower permeability than normal wood, which cause problems for lumber drying. The high moisture content of wetwood usually requires relatively long periods for adequate drying; consequently, it causes a high risk for developing checks, splits, crook, bow and twist of lumber in kiln drying. These problems have not been solved by any physical, chemical or mechanical methods yet. Using biological method to pre-dry lumber containing wetwood is a new concept introduced in this project. Wetwood is formed by bacteria growth inside normal wood. Some fungi are able to kill bacteria and to utilize foetid liquid produced by these micro-organisms. Consequently, the permeability of wetwood can be increased and the lumber drying rate can be improved. The present project intends a research on biological method to pre-dry lumber containing wetwood, and to evaluate efficacy and economic benefit of such a biological treatment. Wetwood of balsam fir, sub-alpine fir and aspen was cultured on nutrient media, and several species of bacteria and yeasts were isolated. The bacteria and yeasts were re-inoculated on normal wood of balsam fir. All inoculated micro organisms caused wetwood formation in 2 weeks. The MC of the inoculated wood blocks increased from 41% to 220-240%, whereas the control samples without inoculation reached only 110%. When control samples were dried to a MC of 13%, the inoculated wood samples still had MCs between 80% and 105%. The selection of biological control agents was conducted on both agar plates and on balsam fir wetwood blocks, and 2 fungal candidates demonstrated promising results. The field test showed that pre-treating balsam fir wetwood lumber with the selected best biocontrol candidates, wood stain was reduced by 94%, warping reduced up to 13%, and checking reduced up to 30% compared with untreated controls. Drying time was reduced by 33% (24 hours) compared with drying fresh lumber. CT scanner was able to detect wetwood locations inside a piece of lumber, and the wetwood was identified in heartwood, sapwood or both wood tissues. After the bio-treatment, the wetwood contents of boards were significantly reduced. Economical analysis showed that the biological treatment would cost $4-7/Mfbm depending on treating method used. Reduction of 33% of drying time by the treatment in this study could save energy cost by $6-13/Mfbm depending on kiln drying energy used. The treatment could reduce lumber degrading loss by $8.5-37.4/Mfbm base on this study. The benefit of the treatment is significant, but will be affected by pre-drying operation, kiln type, energy use and drying schedule. The biological treated lumber is resistant to fungal infection during pre-drying period, and the lumber products are clean and free of moulds and stain infection. Acknowledgements We specifically would like to thank Pierre Lemieux, Scierie Leduc, for providing testing wetwood materials. We also appreciate the support and guidance provided by the project’s industry liaison officers: François Saillant, Natural Resources Canada; Léandre Bélanger, Domtar. Their participation was the key to the success of this project.
Wetwood
Seasoning - Predrying
Yeasts
Bacteria
Biological Control
Fungi
Documents
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Effectiveness of barriers to minimize VOC emissions, including formaldehyde

https://library.fpinnovations.ca/en/permalink/fpipub39025
Author
Barry, A.
Date
March 2007
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barry, A.
Contributor
Canada. Natural Resources Canada
Date
March 2007
Material Type
Research report
Physical Description
39 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Pollution control
Pollution
Materials
Air pollution
Air
Series Number
Value to Wood No. FCC 72
5351
Location
Québec, Québec
Language
English
Abstract
Since the energy crisis in the early 1970s, there has been a decided trend towards tightly constructed buildings that conserve energy and reduce costs. The downside of these well-intended efforts has been the lowering of interior air exchange rates, to the extent that many chemical contaminants are now being trapped indoors where people spend most of their lives. These contaminants may include volatile organic compounds (VOCs), such as formaldehyde, that have been suggested by some to be among the factors responsible for this air quality deterioration. Wood composite panels, which contain formaldehyde such as particleboard and medium density fiberboard (MDF)are often targeted for strict emission regulations or prohibited altogether, despite the fact that this industry has reduced formaldehyde emissions of raw panels by more than 80% over the past twenty years, thereby actually minimizing indoor air contaminants. Moreover, most consumer products made with composite panels are not used in a raw form, but instead have some type of surface finish over the substrate, that generally acts as a barrier to off-gassing, and subsequently reduces emissions. In this 2003 research, ten commonly used finishes were evaluated for their effectiveness as emissions barriers for formaldehyde and total volatile organic compounds (TVOC). It appeared that the powder coating is among the most effective barriers for both formaldehyde and VOCs, with more than 90% emission reduction when applied to MDF. A similar efficiency was observed with phenolic, vinyl, melamine paper, aluminium oxide overlay, Syn Décor laminates, thermofoil 12mil, and 2 mils Natural vinyl applied on particleboard panels. Some finishing material showed excellent efficiency towards formaldehyde reduction with, however, a lower VOC emission reduction such as birch finishing etc. Results also suggested an evaluation of powder coatings on particleboard, and, if practical the clear coating and vinyl laminate on MDF to more fully evaluate the impact of the substrate, if any, on emission characteristics of these surface treatments. The evaluation of the other finishing materials which showed an excellent efficiency on a particular type of product such as particleboard also need to be evaluated on the other product such as MDF in order to complete the evaluation of the effectiveness of any given barrier. The paper finish, water based topcoat, and the multiple (3) topcoat wet process appeared to be the less efficient barriers towards either formaldehyde and/or VOCs with, 41% and 28% formaldehyde emission reduction respectively and an increase of VOC emissions by 79% and 57% respectively, suggesting that these barriers may have high solvent contents. A limitation of this trial study was that the formaldehyde and VOC contribution of the surface coating or laminate were not tested by themselves without a substrate. The very limited number of tests conducted for any individual barriers suggests that these preliminary results should be viewed with caution and that more sampling (confirmatory as well as additional coatings/laminates) is necessary to ensure completeness as well as confidence in the data. The inter-laboratory comparison study, showed some discrepancies on both formaldehyde and TVOC results. The techniques used such as one sample face against two faces, the analytical techniques, the air exchange rates could be responsible for some part of these discrepancies and the very limited number of tests did not help improve the reliability of the results. A very good correlation between ASTM D 5116 and ASTM D 6007 has been established by comparing formaldehyde emission results from the two methods. An R² of 0.94 has been obtained and could be improved by upgrading the database. The decay tests conducted for a long period of time, some samples were tested for more than 200 days, indicated a net decrease of formaldehyde and VOCs emission over time especially for samples with high initial emission rates. For some low initial formaldehyde emitting samples there was no discernable decrease of emissions over time. Decay emission patterns models varied from sample to sample and some were exponential especially for high initial emitting products and some other were polynomial as reported in the literature. The decaying study showed that VOC emissions decayed favourably other time and some sample products showed almost zero emission after few months. This observation is very encouraging because it indicates that most products before being purchased by the client had emitted more than 60 to 70% of their initial emissions levels, particularly those with high initial emission rates. For those with very emission rates such as those finished with powder coatings, melamine, etc, the decaying is not relevant because their emission levels were already at the detection levels.
Air pollution - Control
Composite materials
Finishes
Documents
Less detail

Optimisation de la vitesse de l'air dans les séchoirs

https://library.fpinnovations.ca/en/permalink/fpipub39052
Author
Lavoie, Vincent
Normand, D.
Date
October 2007
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Lavoie, Vincent
Normand, D.
Date
October 2007
Material Type
Research report
Physical Description
9 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Drying
Air
Series Number
E-4267
Location
Québec, Québec
Language
French
Abstract
Les principaux travaux réalisés jusqu’à ce jour en usine incluent la cueillette d‘information sur la géométrie des séchoirs et des empilements et la prise des mesures de puissances électriques de ventilation pour une température de l’air de 20°C pour mettre en relation ces mesures avec les vitesses de l’air dans les séchoirs. Les vitesses de l’air et les puissances ont été mesurées dans 6 séchoirs industriels du Québec par une équipe multidisciplinaire formée de personnel technique de FPInnonations - Division Forintek et de l’Institut de recherche d’Hydro-Québec (Laboratoire des Technologies de l’Énergie de Shawinigan). Ces travaux conjoints découlent de l’initiative ÉlectroBois qui dure depuis près de 6 ans maintenant entre les deux instituts. En plus de réaliser ces mesures, l’équipe en place s’est assurée de documenter la géométrie des séchoirs et des empilements pour orienter des travaux de modélisation qui seront effectués ultérieurement dans le projet. Les mesures réalisées dans différents séchoirs industriels ont permis de documenter différentes géométries d’équipements/d’empilements et différents systèmes de ventilation. Les mesures de puissances et de vitesses de l’air ont permis d’établir l’existence de variations importantes d’efficacité de ventilation entre certains séchoirs. Des facteurs potentiels pouvant expliquer ces différences ont été identifiés. L’outil de modélisation et le banc d’essai de ventilateurs permettront de cibler les facteurs ayant le plus d’influence sur l’efficacité de ventilation ce qui permettra à la fin du projet d’établir des recommandations sur l’optimisation de la vitesse de l’air.
séchoir à bois
Documents
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Effectiveness of barriers to minimize VOC emissions, including formaldehyde

https://library.fpinnovations.ca/en/permalink/fpipub38953
Author
Barry, A.
Date
March 2006
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barry, A.
Contributor
Canada. Natural Resources Canada
Date
March 2006
Material Type
Research report
Physical Description
20 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Pollution control
Pollution
Materials
Air pollution
Air
Series Number
Value to Wood No. FCC 32
4506
Location
Québec, Québec
Language
English
Abstract
Since the energy crisis in the early 1970s, there has been a decided trend towards tightly constructed buildings that conserve energy and reduce costs. The downside of these well-intended efforts has been the lowering of interior air exchange rates, to the extent that many chemical contaminants are now being trapped indoors where people spend most of their lives. These contaminants may include volatile organic compounds (VOCs), such as formaldehyde, that have been suggested by some to be among the factors responsible for this air quality deterioration. Wood composite panels, which contain formaldehyde such as particleboard and medium density fiberboard (MDF) are often targeted for strict emission regulations or prohibited altogether, despite the fact that this industry has reduced formaldehyde emissions of raw panels by more than 80% over the past twenty years, thereby actually minimizing indoor air contaminants. Moreover, most consumer products made with composite panels are not used in a raw form, but instead have some type of surface finish over the substrate, that generally acts as a barrier to off-gassing, and subsequently reduces emissions. In this year’s research, ten commonly used finishes were evaluated for their effectiveness as emissions barriers for formaldehyde and total volatile organic compounds (TVOC). It appeared that the powder coating is among the most effective barriers for both formaldehyde and VOCs, with more than 90% emission reduction when applied to MDF. A similar efficiency was observed with phenolic, vinyl, melamine paper, aluminium oxide overlay, Syn Décor laminates, thermofoil 12mil, and 2 mils Natural vinyl applied on particleboard panels. Some finishing material such as birch veneer showed excellent efficiency towards formaldehyde reduction with, however, a lower VOC emission reduction. Results also suggested further evaluation of other combinations of substrate and finish need to be considered (powder coatings on particleboard, clear coating or vinyl laminate on MDF) to more fully evaluate the impact of the substrate, if any, on emission characteristics of these surface treatments. The evaluation of the other finishing materials which showed an excellent efficiency on a particular type of product such as particleboard also need to be evaluated on the other product, in this case MDF in order to complete the evaluation of the effectiveness of any given barrier. The paper finish, water based topcoat, and the multiple (3) topcoat wet process appeared to be the less efficient barriers to either formaldehyde and/or VOCs with, 41% and 28% formaldehyde emission reduction respectively and an increase of VOC emissions by 79% and 57% respectively, suggesting that these barriers may have high solvent contents. A limitation of this first study was that the formaldehyde and VOC contribution of the surface coating or laminate were not tested by themselves without a substrate. The very limited number of tests conducted for any individual barriers suggests that these preliminary results should be viewed with caution and that more sampling is necessary to ensure completeness as well as confidence in the data. The next phase of this study will include an inter-laboratory comparison study, further evaluation of the finishes and the effect of sample aging as it relates to emissions. A very good correlation between ASTM D 5116 and ASTM D 6007 has been established by comparing formaldehyde emission results from the two methods. An R² of 0.94 has been obtained and could be improved by expanding the database.
Air pollution - Control
Composite materials
Finishes
Documents
Less detail

Biological method to pre-dry lumber with wetwood

https://library.fpinnovations.ca/en/permalink/fpipub38957
Author
Yang, D.-Q.
Date
March 2006
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Date
March 2006
Material Type
Research report
Physical Description
67 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Yeasts
Wetwoods
Seasoning
Bacteria
Series Number
General Revenue Project No. 4030
4030
Location
Québec, Québec
Language
English
Abstract
Wetwood, or water pocket, has higher moisture content and lower permeability than normal wood, which cause problems for lumber drying. The high moisture content of wetwood usually requires relatively long periods for adequate drying; consequently, it causes a high risk for developing checks, splits, crook, bow and twist of lumber in kiln drying. These problems have not been solved by any physical, chemical or mechanical methods yet. Using biological method to pre-dry lumber containing wetwood is a new concept introduced in this project. Wetwood is formed by bacteria growth inside normal wood. Some fungi are able to kill bacteria and to utilize foetid liquid produced by these micro-organisms. Consequently, the permeability of wetwood can be increased and the lumber drying rate can be improved. The present project intends a research on biological method to pre-dry lumber containing wetwood, and to evaluate efficacy and economic benefit of such a biological treatment. Trees of balsam fir, sub-alpine fir and aspen were felled and cut into lumber. Isolation of causal agents was conducted from wet pockets of these wood species by using peptone agar and malt extract agar media. A total of 319 cultures were obtained from the wetwood of these three wood species. Three bacteria and two yeasts were isolated from balsam fir wetwood, 2 bacteria and 1 yeast were more frequently isolated from aspen wetwood, and 2 bacteria and 5 yeasts were obtained from sub-alpine fir. Two bacteria were isolated from the wetwood of all 3 wood species: Shigella sonnei and Pseudomonas fluorescens. Other bacteria and yeasts isolated were identified as Aerococcus viridans, Chryseomonas luteol, Candida boidinli, C. zeylanoides, Cryptococcus albidus, C. laurentii, C. terreus, and Rhodotorula mucileginosa. In addition to these identified bacteria and yeasts, two other yeasts isolated from balsam fir and sub-alpine fir wetwood were unabile to be identified. Six bacteria and yeast isolates were re-inoculated on normal wood of balsam fir; they were A-a (a bacterium isolated from aspen and identified as Shigella sonnei), A-c (a yeast isolated from aspen and identified as Cryptococcus laurentii), B-a (a bacterium isolated from balsam fir and identified as Shigella sonnei), B-c (a mixture of 2 bacteria isolated from balsam fir and identified as Shigella sonnei and Aerococcus viridans), Y-2 (an unidentified yeast isolated from balsam fir), and SaB-2 (a bacterium isolated from sub-alpine fir and identified as Shigella sonnei). The result showed that all of these micro-organisms caused wetwood formation on inoculated normal wood samples in 2 weeks. This result indicates that wetwood formation in trees is not caused by only 1 micro-organism but is more likely caused by several species (either bacteria or yeasts) that can colonise well in the wood of trees. The moisture contents (MC) of the inoculated wood blocks increased from 41.2% to 220-240 %, whereas the MCs of the control samples submerged in a liquid culture medium without inoculation reached only 110%. When control samples were dried to a MC of 13%, the inoculated wood samples still had MCs between 80% and 105%. This result indicates that drying lumber containing wetwood will take double the time required to dry normal lumber without wetwood. An antagonist test using fungal candidates was conducted on agar plates. In this test, 6 potential fungal antagonists and 6 wetwood causal agents (WCA) were used. The six fungal antagonists were Gliocladium roseum (a bioprotectant developed by Forintek), a white isolate of Ophiostoma piliferum (a fungus used in a commercial bioprotectant, Cartapip), a white isolate of Ceratocystis resinifera (an anti-sapstain biological agent used by Chantal Morin at Laval University), Geotrichum sp.A (a white fungus in Deuteromycetes isolated from Jack pine logs, DP3/5B-3a, 1998), Geotrichum sp. B (a white fungus in Deuteromycetes isolated from balsam fir logs, DF3/1B-1b, 1998), and Phaeotheca dimorphospora (a biological control agent of tree disease from Laval University). The six wetwood causal agents were A-a (a bacterium isolated from wetwood of aspen), A-c (a yeast isolated from wetwood of aspen), B-a (a bacterium isolated from wetwood of balsam fir), Y-2 (a yeast isolated from wetwood of balsam fir), SaB-2 (a bacterium isolated from wetwood of sub-alpine fir), and SaY-4 (a mixture of a yeast and a bacterium isolated from wetwood of sub-alpine fir). The results showed that Geotrichum sp.A and Geotrichum sp.B were the most effective against all 6 WCA inoculated; they reduced growth of the WCA in 7 days and completely absorbed colonies of WCA in 11 days. G. roseum, O. piliferum, and C. resinifera were moderately effective against 5 WCAs, but not effective on bacterium A-a that was isolated from aspen wetwood. P. dimorphospora was the least effective against any of these WCA. The three promising fungal antagonists, Geotrichum sp., G. roseum and the white isolate of O. piliferum, selected from agar plate test were used for an antagonist test on balsam fir wetwood blocks in the laboratory conditions. This test was conducted on small wetwood samples (2 x 4 x 1 inch) in incubators at 25°C and two relative humidity ranges (100% and 75% RH). The results showed that all these three fungi were able to establish on wood surfaces and able to reduce wetwood contents. At 25°C and 75% RH, Geotrichum sp. was the most effective to reduce wetwood content in samples, followed by G. roseum, and then by O. piliferum. G. roseum and Geotrichum sp. not only reduce wetwood content, but also inhibit mold growth and wood stain, compared with untreated control samples. At 25°C and 100% RH, the moisture contents of treated and untreated samples were not changed in any week of the testing period. This result indicates that biological pre-dry wetwood samples should not be conducted at this high relative humidity condition. A test was conducted to investigate the inhibitory ability of Geotrichum sp., the wetwood control candidate, against sapstaining fungi on wood. The results showed that if balsam fir wood wafers were inoculated with Geotrichum sp. 3 days before the staining fungi, no staining fungi grew on these samples. If wood wafers were inoculated with Geotrichum sp. and staining fungi at the same time, samples were covered by both Geotrichum sp. and the staining fungus Ophiostoma piceae in a ratio of 1:1. If wood wafers were inoculated with the staining fungi 3 days before Geotrichum sp., samples were absolutely covered by the staining fungus and fully stained. A study on environmental effects on the growth of Geotrichum sp., the wetwood control agent, showed that this fungus started growth at 5°C, had optimal growth between 20-25°C, stopped growth at 30°C, and died at 40°C. Geotrichum sp. had a wide range of pH requirement and grew well in agar medium at pHs between 3 and 10. Geotrichum sp. started to grow at 29% MC, and the speed of the growth increased along with the increase of MC in wood. The best fungal growth of Geotrichum sp. was observed on wood blocks containing 56% MC. Geotrichum sp. was able to grow on wood of jack pine, black spruce, balsam fir, sub-alpine fir and aspen, but it grew better on wood of jack pine, balsam fir and black spruce than on sub-alpine fir and aspen. Geotrichum sp. was able to grow together with an anti-sapstain fungus, Gliocladium roseum, without any antibiotic or incompatible growth reaction. In the laboratory conditions, the biological treated boards reduced wood MC by 22-37% more than untreated boards. Untreated boards were fully covered by molds and stain after 8 weeks in storage, and 0% of boards was acceptable for use. The biological treated boards were less affected, with 35-75% of pieces acceptable. The time required for drying biological treated boards was estimated reducing by 10.5 hours compared with untreated controls. After drying, the biological treated boards reduced the rate of crook, bow and twist by 5-20%, but increased the rate of split and check by 5-12%, compared with untreated controls. The total deformation rate was reduced up to 5% by the best biological treatment. In the field conditions, untreated boards were 100% affected by molds and stain after 8 weeks in storage, whereas the best biological treated boards were only affected by 6%. Drying biological treated and untreated boards took similar times, but it was estimated reducing drying time by 48 hours compared with fresh boards. Compared with untreated controls, the biological treated boards reduced the rate of crook, bow and twist by 2-13%, and reduced the rate of split and check by 3-30%. The total deformation rate was reduced by 5-22%, depending on the treatments. CT scanner was able to detect wetwood locations inside a piece of lumber, and the wetwood present in either heartwood, sapwood or both wood tissues. After the bio-treatment, the wetwood contents of boards were significantly reduced.
Wetwood
Seasoning - Predrying
Yeasts
Bacteria
Biological Control
Fungi
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Impact of airflow on the drying rate of black spruce

https://library.fpinnovations.ca/en/permalink/fpipub38975
Author
Normand, D.
Lavoie, Vincent
Date
June 2006
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Normand, D.
Lavoie, Vincent
Date
June 2006
Material Type
Research report
Physical Description
16 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Transfer
Simulation
Seasoning kiln drying
Seasoning
Drying
Kilns
Heat transfer
Heat
Air
Series Number
General Revenue Project No. 4033
4033
Location
Québec, Québec
Language
English
Abstract
In both conventional and dehumidification drying, airflow is essential to transfer the heat needed to warm up the lumber, evaporate water from the wood surface and remove the resulting moisture. Faster airflow means greater energy transfer at the wood surface. It also means faster water removal from the wood surface. How much productivity can be gained from increasing air velocity by 100 ft/min? The objective of this study was to determine the effect of air velocity on productivity, lumber quality and energy consumption in the drying of spruce-pine-fir (SPF) construction lumber in eastern Canada. The authors initially used the Drytek modeling software to evaluate the effect of air velocity on drying productivity. Modeling studies on balsam fir, jack pine and black spruce demonstrated a positive effect of increased air velocity on drying productivity. They conducted laboratory tests on 2x4x8-ft lumber from the Lac Saint-Jean, Quebec area. These tests used the same moisture content-driven schedule at four different air velocities, i.e.: 300, 600, 900 and 1200 ft/min. The study showed that, on the basis of initial moisture content (MC) of 40% and a final MC of 15%, a 100-ft/min increase in air velocity raised productivity by approximately 2%. Gains in drying time were obtained only from the green state down to the fibre saturation point (FSP), which corresponds to 25-30% MC. Higher air velocity did not reduce drying time below FSP. Consequently, the gains obtained from raising air velocity by 100 ft/min are greater when the initial moisture content is higher than 40% than when it is below that level. Final moisture content variations between and within pieces were comparable at the different air velocity levels, as a result lumber quality was also comparable. A visual assessment of lumber distortion in the piles showed no significant difference. The specific power consumption of the ventilation system was 0.1, 0.2, 0.6 and 1.0 kWh/kgevaporated water respectively at air velocities of 300, 600, 900 and 1200 ft/min, but this level of specific power consumption is only applicable to the laboratory kiln used in the tests. Preliminary industry data suggest that specific power consumption for black spruce would be 0.06, 0.11, 0.14 and 0.18 kWh/kgevaporated water for the same air velocities in the more efficient industrial kilns. These values will need to be confirmed in the second phase of the study. Economic calculations on the productivity gains obtained from higher air velocities indicate that annual revenues from a given kiln capacity can be increased. A productivity gain of 2% resulting from a 100-ft/min air velocity increase yields additional revenues of $1/Mbf of dry lumber, assuming a dry/green price differential of $50/Mbf. At a $100/Mbf price differential, the revenue gain becomes $2/Mbf. Additional costs related to high air velocity should however be subtracted from such potential gains. For example, the modification or addition of baffles, or the adjustment of fan blades may lead to higher air velocity at minimal cost to the company; and power consumption will not increase significantly, as the system continues to move the same quantity of air per unit of time. If, on the other hand, a more powerful ventilation system is required, this will involve some capital cost as well as increased power consumption per unit of dry lumber. Mills should take these additional costs into consideration before deciding whether to modify the equipment. To minimize electrical energy costs when increasing air velocity, producers can also adjust air velocity in relation to the different phases of the drying schedule, given that fan speed can be reduced when the lumber moisture content falls below the fibre saturation point. A previous Forintek study showed that lower fan speed below the FSP level could reduce power consumption with no negative effect on kiln productivity. The current study confirmed that higher air velocity did not result in productivity gains below the FSP level. Mills using high air velocities would therefore generate substantial cost savings by lowering fan speed in the final phases of the cycle. This would require some means to identify when the FSP is reached and the use of variable speed drives for the air circulation system. As part of this study, we used a software program to model airflow in one of Forintek’s experimental kilns with an actual lumber load. We then compared air velocity on the exit side of the stack according to the model versus actual velocity as measured in the kiln. As the values obtained from the two sources were similar, we believe that our model may prove a very useful tool to simulate the effect of modifying kiln geometry. It will allow producers to assess the effect of modifications such as new or modified baffles or a different roof angle on airflow before they make any decision. In summary, lumber manufacturers should keep the following points in mind before deciding to modify the airflow system:
Ensure sufficient air space in-between rows with good stickering and stacking practices, as well as proper use of baffles.
Optimize fan blade angle in order to use installed motor power as efficiently as possible.
Ensure that the system can provide sufficient heat energy. With increased airflow, the kiln will require the same amount of heat energy to dry a given load, but over a shorter period of time.
Consider installing a variable-speed drive to reduce airflow below the fibre saturation point, thus reducing energy consumption.
Consider the effect of air velocity on systems based on the temperature drop across the load (TDAL). Adjustments to airflow may result in changes to TDAL measurements and require modifications to the drying schedule. Further work is needed to finalize the recommendations based on this study. Over the coming year, we will run tests on balsam fir and jack pine to determine potential productivity gains from increased airflow with these species. We will also analyze in more detail how power should best be managed and used under industrial conditions. These follow-up studies will be conducted in collaboration with Hydro Quebec’s Laboratoire des Technologies de l’Énergie (LTE), in Shawinigan, Quebec as part of our joint Électrobois II program.
Seasoning - Kiln drying - Computer simulation
Air flow
Heat transfer
Documents
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Impact of Kyoto Protocol on composite panel industries

https://library.fpinnovations.ca/en/permalink/fpipub38939
Author
Barry, A.
Date
March 2006
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barry, A.
Contributor
Canada. Canadian Forest Service
Date
March 2006
Material Type
Research report
Physical Description
25 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Regulations
Pollution
Materials
Canada
Air pollution
Air
Series Number
Canadian Forest Service No. 15
4005
Location
Québec, Québec
Language
English
Abstract
The work conducted under the Kyoto Protocol, can be summarized by extracting some paragraphs from the Montreal Climate Conference press release. Under the Kyoto Protocol, which entered into force February 16, 2005, more than 30 industrialized countries are bound by specific and legally binding emission reduction targets. These cover the period 2008-2012, as a first step. The Kyoto Protocol is now fully operational. The adoption of the Marrakesh accords formally launches emissions trading and the other two mechanisms under the Kyoto Protocol. Carbon now has a market value. Under the clean development mechanism, investing in projects that provide sustainable development and reduce emissions makes sound business sense. The Joint Implementation (JI) adopted by the parties is one of the mechanisms which allows developed countries to invest in other developed countries and thereby earn carbon allowances, which they can use to meet their emission reduction commitments. In addition to this, the clean development mechanism allows industrialized countries to invest in sustainable development projects in developing countries and thereby earn carbon allowances. “With these decisions in place, we now have the infrastructure to move ahead with the implementation of the Kyoto protocol” said Richard Kinley, head of the United Nations Climate Change conference. “It sets solid basis for future steps to bring emissions down,” he added. All Kyoto Protocol Parties, including Canada, are now moving ahead to meet their GHG emission reduction commitments. In the past few years, Canada has developed and set strategies to meet our commitments. Canada has recently elected a new Conservative Federal government and the new position in regards to the Protocol and what strategies will be adopted by this government, is unknown at this time. However, because H.E. Ms Rona Ambrose has been confirmed by both the Canadian Government and the United Nations as the new President of the Conference of the Parties (COP), we will very soon know what will be the new Canadian position.
Composite materials
Air pollution - Canada - Laws and regulations
Documents
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Study of VOC emissions from a MDF pilot plant

https://library.fpinnovations.ca/en/permalink/fpipub38940
Author
Barry, A.
Date
March 2006
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barry, A.
Contributor
Canada. Canadian Forest Service.
Date
March 2006
Material Type
Research report
Physical Description
39 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Pollution
Air pollution
Air
Series Number
Canadian Forest Service No. 40
1953
Location
Québec, Québec
Language
English
Abstract
A series of experiments were conducted with Forintek’s MDF pilot plant to investigate the impact of various process parameters on MDF dryer stack emissions. Resin types, resin loading, wood furnish and scavenger levels were among the factors investigated in this study. Stack emissions were analyzed for particulate matters (PM), speciated volatile organic compounds (VOCs) and total volatile organic compounds (TVOC). Two series of results were reported. During the first series of test runs, the isokinetic PM sampling was not obtained while with the second series, all test runs were conducted under isokinetic conditions, which make results more reliable. PM results from the second series of runs did not indicate a clear impact of the investigated refining conditions. However, all PM results were well below provincial guidelines for PM emission limits, particularly those from the province of British Columbia. Other results clearly showed that increasing resin loading resulted in an increase of individual VOCs (IVOCs) and total VOC. The replacement of UF resin by MUF resin contributed to a decrease of both IVOCs and TVOC.
Fibreboard
Air pollution - Sources
Documents
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Manufacture of MDF using a powder resin

https://library.fpinnovations.ca/en/permalink/fpipub5591
Author
Feng, Martin
Deng, James
Date
March 2005
Edition
37741
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Feng, Martin
Deng, James
Date
March 2005
Edition
37741
Material Type
Research report
Physical Description
65 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Toxicity
Synthetics
Polymers
Pollution
Air pollution
Air
Series Number
4529
W-2179
Location
Vancouver, British Columbia
Language
English
Abstract
The objective of this project was to help Forintek members to reduce formaldehyde and VOC emissions from MDF mills and increase resin efficiency. Five novel blending methods were examined: 1. Post-dryer air-suspension blending with a PF powder resin (resol). 2. Post-dryer air-suspension blending with a PF powder resin and a liquid PF resin (resol). 3. Post-dryer air-suspension blending with a UF powder resin. 4. Post-dryer air-suspension blending with a UF powder resin and a liquid UF resin. 5. Refiner blending with a PF powder resin (novalac) The following conclusions and recommendations are made: It is feasible to produce MDF panels from blending powder PF resin (resol) with wood fibre at 8% MC & 5% wax using a post-dryer air-suspension blender. Combination of liquid and powder PF resins at a ratio of 1:1 appeared to work better. The thickness swell and water absorption were significantly lower than those obtained from panels bonded with liquid PF or powder PF alone. It is feasible to produce MDF panels from blending powder UF resin with wood at 7% MC & 5% wax using a post-dryer air-suspension blender. Similar to the case of PF resin, the combination of liquid UF and powder UF at a ratio of 1:1 appeared to work better than liquid UF or powder UF alone. Unlike PF powder resin, however, UF powder was softened quickly by moisture, causing some blender build-up. There is room for improving UF powder resin performance by resin formula modification and the reduction of its water solubility. It is feasible to produce MDF panels from blending a novalac resin with wood in a MDF refiner. Further exploration of this novel blending method in Forintek's MDF pilot plant is recommended. Results from this project shoed that there are new possibilities for the next generation of MDF blending. These new methods will be able to overcome the disadvantages and preserve or even enhance the advantages of the existing blending methods. This project has demonstrated that, by changing the physical properties of a resin, it is possible to develop an improved MDF blending system. Using a powder resin in a post-dryer blending system may dramatically reduce resin consumption and formaldehyde emission from the MDF mills. The combination of a liquid resin with a powder resin is another possibility. In this case, perhaps a certain amount of liquid resin is delivered to a post-dryer mechanical blender or post-dryer air-suspension blender or via the blowline to produce some tack in the fibre while a powder resin is blended with the fibre in this post-dryer mechanical blender or post-dryer air-suspension blender. The powder resin may also be delivered at the end section of the tube dryer. Because the powder resin is blended after the dryer, the loss of resin efficiency can then be greatly reduced. The authors believe that there is great potential for technological advancement in this area. In order to explore the full potential of powder resin blending in MDF manufacturing, joint research with a reputable blending equipment manufacturer is highly recommended.
Polymers, Synthetic
Fibreboard
Air pollution - Sources
Formaldehyde - Toxicity
Documents
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Biological method to pre-dry lumber with wetwood

https://library.fpinnovations.ca/en/permalink/fpipub42290
Author
Yang, D.-Q.
Date
March 2005
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Date
March 2005
Material Type
Research report
Physical Description
44 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Yeasts
Wetwoods
Seasoning
Bacteria
Series Number
General Revenue 4030
Location
Sainte-Foy, Québec
Language
English
Abstract
Wetwood, or water pocket, has higher moisture content and lower permeability than normal wood, which cause serious problems for lumber drying. The high moisture content of wetwood usually requires relatively long periods for adequate drying; consequently, it causes a high risk for developing checks, splits, crook, bow and twist of lumber in kiln drying. These problems have not been solved by any physical, chemical or mechanical methods yet. Using biological method to pre-dry lumber containing wetwood is a new concept introduced in this project. Wetwood is formed by bacteria growth inside normal wood. Some fungi are able to kill bacteria and to utilize foetid liquid produced by these micro-organisms. Consequently, the permeability of wetwood can be increased and the lumber drying rate can be improved. The present project intends a research on biological method to pre-dry lumber containing wetwood, and to evaluate efficacy and economic benefit of such a biological treatment. Trees of balsam fir, sub-alpine fir and aspen were felled and cut into lumber. Isolation of causal agents was conducted from wet pockets of these wood species by using peptone agar and malt extract agar media. A total of 319 cultures were obtained from the wetwood of these three wood species. Three bacteria and two yeasts were isolated from balsam fir wetwood, 2 bacteria and 1 yeast were more frequently isolated from aspen wetwood, and 2 bacteria and 5 yeasts were obtained from sub-alpine fir. Two bacteria were isolated from the wetwood of all 3 wood species: Shigella sonnei and Pseudomonas fluorescens. Other bacteria and yeasts isolated were identified as Aerococcus viridans, Chryseomonas luteol, Candida boidinli, C. zeylanoides, Cryptococcus albidus, C. laurentii, C. terreus, and Rhodotorula mucileginosa. In addition to these identified bacteria and yeasts, two other yeasts isolated from balsam fir and sub-alpine fir wetwood were unabile to be identified. Six bacteria and yeast isolates were re-inoculated on normal wood of balsam fir; they were A-a (a bacterium isolated from aspen and identified as Shigella sonnei), A-c (a yeast isolated from aspen and identified as Cryptococcus laurentii), B-a (a bacterium isolated from balsam fir and identified as Shigella sonnei), B-c (a mixture of 2 bacteria isolated from balsam fir and identified as Shigella sonnei and Aerococcus viridans), Y-2 (an unidentified yeast isolated from balsam fir), and SaB-2 (a bacterium isolated from sub-alpine fir and identified as Shigella sonnei). The result showed that all of these micro-organisms caused wetwood formation on inoculated normal wood samples in 2 weeks. This result indicates that wetwood formation in trees is not caused by only 1 micro-organism but is more likely caused by several species (either bacteria or yeasts) that can colonise well in the wood of trees. The moisture contents (MC) of the inoculated wood blocks increased from 41.2% to 220-240 %, whereas the MCs of the control samples submerged in a liquid culture medium without inoculation reached only 110%. When control samples were dried to a MC of 13%, the inoculated wood samples still had MCs between 80% and 105%. This result indicates that drying lumber containing wetwood will take double the time required to dry normal lumber without wetwood. An antagonist test using fungal candidates was conducted on agar plates. In this test, 6 potential fungal antagonists and 6 wetwood causal agents (WCA) were used. The six fungal antagonists were Gliocladium roseum (Forintek bioprotectant), a white isolate of Ophiostoma piliferum (Cartapip), a white isolate of Ceratocystis resinifera (an anti-sapstain biological agent produced by Chantal Morin at Laval University), Oidium sp.A (a white fungus in Deuteromycetes isolated from Jack pine logs, DP3/5B-3a, 1998), Oidium sp. B (a white fungus in Deuteromycetes isolated from balsam fir logs, DF3/1B-1b, 1998), and Phaeotheca dimorphospora (a biological control agent of tree disease from Laval University). The six wetwood causal agents were A-a (a bacterium isolated from wetwood of aspen), A-c (a yeast isolated from wetwood of aspen), B-a (a bacterium isolated from wetwood of balsam fir), Y-2 (a yeast isolated from wetwood of balsam fir), SaB-2 (a bacterium isolated from wetwood of sub-alpine fir), and SaY-4 (a mixture of a yeast and a bacterium isolated from wetwood of sub-alpine fir). The results showed that Oidium sp.A and Oidium sp.B were the most effective against all 6 WCA inoculated; they reduced growth of the WCA in 7 days and completely absorbed colonies of WCA in 11 days. G. roseum, O. piliferum, and C. resinifera were moderately effective against 5 WCAs, but not effective on bacterium A-a that was isolated from aspen wetwood. P. dimorphospora was the least effective against any of these WCA. The three promising fungal antagonists, Oidium sp., G. roseum and the white isolate of O. piliferum, selected from agar plate test were used for a following antagonist test on balsam fir wetwood blocks in the laboratory conditions. This test was conducted on small wetwood samples (2 x 4 x 1 inch) in incubators at 25°C and two relative humidity ranges (100% and 75% RH). The results showed that all these three fungi were able to establish on wood surfaces and able to reduce wetwood contents. At 25°C and 75% RH, Oidium sp. was the most effective to reduce wetwood content in samples, followed by G. roseum, and then by O. piliferum. G. roseum and Oidium sp. not only reduce wetwood content, but also inhibit mold growth and wood stain, compared with untreated control samples. At 25°C and 100% RH, the moisture contents of treated and untreated samples were not changed in any week of the testing period. This result indicates that biological pre-dry wetwood samples should not be conducted at this high relative humidity condition. A test was conducted to investigate the ability of Oidium sp., the wetwood control candidate, against sapstaining fungi on wood. The results showed that if balsam fir wood wafers were inoculated with Oidium sp. 3 days before the staining fungi, no staining fungi grew on these samples. If wood wafers were inoculated with Oidium sp. and staining fungi at the same time, samples were covered by both Oidium sp. and the staining fungus Ophiostoma piceae in a ratio of 50 to 50%. If wood wafers were inoculated with the staining fungi 3 days before Oidium sp., samples were absolutely covered by the staining fungus and fully stained.
Wetwood
Seasoning - Predrying
Yeasts
Bacteria
Biological Control
Fungi
Documents
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Impact de la vitesse de l'air sur le taux de séchage de l'épinette noire

https://library.fpinnovations.ca/en/permalink/fpipub42328
Author
Normand, D.
Lavoie, Vincent
Date
October 2005
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Normand, D.
Lavoie, Vincent
Date
October 2005
Material Type
Research report
Physical Description
16 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Transfer
Simulation
Seasoning kiln drying
Seasoning
Drying
Kilns
Heat transfer
Heat
Air
Series Number
Projet General Revenue no 4033
Location
Sainte-Foy, Québec
Language
French
Abstract
La circulation de l’air est essentielle (en séchage conventionnel et par déshumidification) pour le transfert de la chaleur nécessaire au réchauffement du bois, à l’évaporation de l’eau de surface et au transport de cette humidité. Plus la vitesse de l’air est élevée, plus le taux de transfert d’énergie à la surface du bois est grand. Ceci se traduit par une augmentation du taux d’évaporation de l’eau à la surface du bois Quel gain de productivité peut-on obtenir à la suite d’une augmentation de la vitesse de l’air de 100 pi/min? Cette étude a pour objectif de déterminer l’impact de la vitesse de l’air sur la productivité, la qualité et la consommation énergétique du séchage du bois de construction ÉPS de l’est du Canada. Initialement, le logiciel de modélisation Drytek a été utilisé pour étudier l’effet de la vitesse de l’air sur la productivité du séchage. Les résultats des modélisations du sapin baumier, du pin gris et de l’épinette noire ont démontré un effet positif sur la productivité à la suite de l’augmentation de la vitesse de l’air. Des essais de laboratoire ont été faits sur du bois de construction d’épinette noire 2x4x8’ provenant de la région du Lac-St-Jean au Québec. Ces essais utilisant le même programme de séchage dicté par la teneur en humidité ont été réalisés pour quatre vitesses de l’air différentes soit 300, 600, 900 et 1200 pi/min. L’étude a démontré que la vitesse de l’air a un impact sur la productivité du séchage d’environ 2 % par augmentation de 100 pi/min de la vitesse de l’air considérant une teneur en humidité initiale de 40 % et une teneur en humidité finale de 15 %. Les gains de temps de séchage ont été obtenus uniquement de l’état vert au point de saturation des fibres (PSF). Le PSF correspond à une teneur en humidité de 25 à 30 %. Mentionnons qu‘aucune diminution du temps de séchage n’a été observée sous le PSF à la suite de l’augmentation de la vitesse de l’air. Ainsi, une teneur en humidité initiale supérieure à 40 % procure des gains supérieurs à 2 % par 100 pi/min et une teneur en humidité initiale inférieure à 40 % procure des gains inférieurs à cette valeur. Les variations de teneur en humidité finale entre les pièces et à l’intérieur des pièces sont similaires pour les essais réalisés à différentes vitesses de l’air. Ceci révèle une qualité des sciages semblable entre les essais. De même, le gauchissement évalué visuellement dans les empilements ne montrait pas de différence significative. La consommation électrique spécifique du système de ventilation est respectivement de 0,1, 0,2, 0,6 et 1,0 kWh/kgeau évaporée pour les essais réalisés à 300, 600, 900 et 1200 pi/min. Cette consommation spécifique est applicable uniquement au séchoir de laboratoire utilisé. Des données industrielles préliminaires nous permettent de croire que la consommation électrique spécifique de l’épinette noire est 0,06, 0,11, 0,14 et 0,18 kWh/kgeau évaporée pour les séchoirs industriels les plus efficaces avec les mêmes vitesses de l’air respectives mentionnées plus haut. Ces valeurs sont à confirmer dans une deuxième phase du projet. Des calculs économiques relatifs aux gains en productivité obtenus par l’augmentation de la vitesse de l’air montrent qu’il est possible d’augmenter les revenus annuels pour une capacité de séchage donnée. Un gain en productivité d’environ 2 % par augmentation de 100 pi/min de la vitesse de l’air se traduit par une augmentation des revenus de 1$/Mpmp séché pour un différentiel de prix sec-vert de 50 $/Mpmp. L’augmentation passe à 2$/Mpmp pour un différentiel de prix sec-vert de 100$/Mpmp. Les coûts additionnels doivent cependant être soustraits de ces revenus potentiels pour obtenir le profit additionnel associé à l’augmentation de la vitesse de l’air. À titre d’exemple, la modification ou l’ajout de déflecteurs ou l’ajustement de l’angle des pales des ventilateurs peuvent procurer des augmentations de la vitesse de l’air à coût très minime pour l’entreprise. La modification ou l’ajout de déflecteurs n’entraînera pas d’augmentation de la consommation électrique significative puisque la même quantité d’air par unité de temps est déplacée. Le changement du système de ventilation pour un système plus puissant impliquera un certain coût en capital et une hausse de la consommation électrique par Mpmp séché. Les coûts additionnels d’opération reliés à ces changements devront être pris en considération avant de procéder à une modification. Il est possible d’optimiser la gestion de la vitesse de l’air en fonction de l’étape de séchage de façon à réduire davantage les coûts d’énergie électrique reliés au système de ventilation, En effet, la vitesse des ventilateurs peut être réduite lorsque la teneur en humidité du bois se situe sous le PSF. Une étude réalisée précédemment chez Forintek a démontré qu’il est possible de réduire la consommation électrique du système de ventilation sans affecter la productivité des séchoirs en abaissant la vitesse des ventilateurs sous le PSF. La présente étude confirme que sous le PSF aucun gain en productivité n’est réalisé par une augmentation de la vitesse de l’air. Les usines ayant déjà des vitesses de l’air élevées ont donc intérêt à baisser la vitesse de rotation en fin séchage pour profiter d’économies d’énergie non négligeables. La détermination du PSF et l’utilisation d’un variateur de vitesse sur le système de ventilation sont nécessaires pour réaliser les gains. Un logiciel a été utilisé dans le cadre de cette étude pour modéliser l’écoulement de l’air dans un séchoir expérimental de Forintek. L’écoulement de l’air dans le séchoir avec un empilement réel a été modélisé. Par la suite, la vitesse de l’air obtenue à la sortie de l’empilement par modélisation a été comparée à celle mesurée réellement dans le séchoir. Des valeurs similaires entre la modélisation et la réalité démontrent le potentiel d’un tel outil pour simuler des modifications au niveau de la géométrie d’un séchoir donné. L’impact direct d’une modification (ex : ajout de déflecteurs, angle des déflecteurs et du toit) sur l’écoulement de l’air pourrait être vérifié avant de procéder aux modifications du séchoir. En résumé, il est très important de considérer les points suivants lors d’une modification du système de ventilation:
Favoriser le passage de l’air dans les empilements. Il faut s’assurer d’avoir de bonnes pratiques de lattage et d’empilement et d’utiliser adéquatement les déflecteurs.
Optimiser l’angle des pales des ventilateurs, ce qui permet d’utiliser adéquatement la puissance installée des moteurs.
S’assurer de la disponibilité de l’énergie calorifique. En effet, la même quantité d’énergie calorifique sera nécessaire pour sécher la même quantité de bois, mais dans un intervalle de temps plus court.
Envisager l’utilisation d’un variateur de vitesse pour diminuer la ventilation en dessous du PSF. Cette mesure favorise la réduction de la consommation énergétique.
Considérer l’impact de la vitesse de l’air sur les systèmes de contrôle utilisant le DTAB (différence de température à travers le bois). La modification de la vitesse de l’air peut modifier les lectures des DTAB habituelles et nécessiter des ajustements des programmes de séchage. Des travaux supplémentaires s’avèrent nécessaires pour compléter les recommandations générées par ce projet. Dans la prochaine année, le sapin baumier et le pin gris seront testés pour déterminer le gain en productivité potentiel de l’augmentation de la vitesse de l’air pour ces essences. La gestion et l’utilisation de la consommation électrique des systèmes de ventilation industriels seront également approfondies. Les différents travaux seront réalisés en collaboration avec le Laboratoire des technologies de l’énergie d’Hydro-Québec à Shawinigan dans le cadre du programme ÉlectroBois II.
Seasoning - Kiln drying - Computer simulation
Air flow
Heat transfer
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