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.
Nanoparticles including four metal oxides and two nanoclays were used in a water based coating to compare their effectiveness as emission barriers for formaldehyde and VOCs. Initially five nanoclays (Cloisite 30B, Cloisite Na+, Nanocor 1.30E, Nanocor 1.33M, and nanocor 1.34TCN) were investigated, and based on the quality of their dispersion in water, two of them (Cloisite Na+, and Nanocor 1.30E) were selected. In addition to these two nanoclays, four nanoparticles (Al2O3, Alumina Ceramic (BYK, LPX 2193), nanosilica (Fumed silica Aerosil R7200) and titanium dioxide (Aeroxide P25)) were selected for their VOC off gassing barrier efficiency from particleboard products. Because the coating was water based, the particleboard samples were veneer finished to avoid samples swelling. To glue the veneers a in house UF resin formulated with high U/F ratio to reduce the veneer barrier efficiency as already reported in previous studies. Three loading ratios, 1%, 3% and 5%, of the nanoparticles were investigated but only the two extremes were reported.
The transmission electron microscopy (TEM) results showed that the nanoparticles, including Al2O3, AlCeramic, and TiO2 were well distributed in the coating for both 1wt% and 5 wt% loading ratios. In these formulations, small aggregates were observed with a diameter of about 100-150 nm. It was smaller by about 50nm for the AlCeramic (1%). The Nanosilica and the two nanoclay samples did not disperse well in the coating; they showed larger aggregates with a diameter of about several microns.
In terms of formaldehyde and other carbonyls compounds barrier efficiency, the coating containing the Cloisite Na+ performed the best followed by the samples finished with the nanosilica both at 5% loading. A decrease of these carbonyl compounds emission varied from 60% to almost 70% when 5% of Cloisite Na+ was used in the coating formulation after 7 days samples conditioning.
An overall TVOC emission reduction up to 82% was observed when Cloisite Na+ was added to the coating compared to the veneered and uncoated particleboard sample. This barrier efficiency result is very encouraging for the coating industry and could be considered for technology transfer where optimum conditions for the mixing of nanoparticles with the coating as well as the coating application and curing could be achieved with automated and performing equipments. The technology transfer based on results obtained from this project is highly recommended due to its anticipated lifting the VOC emission barriers from some countries regulations such as CARB for the formaldehyde emission limits and a new legislation for formaldehyde, some particular VOCs and TVOC recently released as DRAFT Regulation, in France.