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Flax shives are a source of abundant biomass from renewable sources. They are considered to be environmentally benign and have a high-energy content for heating and generation of electricity, but only after being processed into pellets. Pelleting of the shives was done by using the single-pelleter and pilot-scale mill. The effect of grinding with screens of 2.4, 3.2, and 6.4 mm on unit density and durability was conducted with a completely randomized design using shives from Biofibre Industries Inc., Canora, SK. The central composite face-centered design with 3 levels of lower grade canola meal used as a binder (18, 21, and 24%), moisture content (8, 11, and 14% (w.b)), and hammer mill screen size (3.2, 4.8, and 6.4 mm) was used to determine the effects of these three factors on the properties of fuel pellets made from shives obtained from Biolin Research Inc., Saskatoon, SK. The initial moisture content of coarse flax shives from both sources was about 10.5% wet basis (w.b.). The moisture content of flax shive grinds ranged from 9.6 to 10.5% (w.b.) after grinding, using the smaller screens for the Biofibre material, while the moisture content ranged from 7.9 to 8.6% (w.b.) for shives from Biolin. Also, smaller screen size reduced the geometric mean particle size for shives from both sources. The use of the smaller hammer mill screen resulted in an increase in both bulk and particle density of shives. There was a decrease in coefficient of the internal friction of shives from 0.20 to 0.14 and an increase in a cohesion of shives from 2.18 to 3.83 kPa when the screen size decreased from 6.4 to 3.2 mm. The flax shives contained cellulose (53.27%), hemicelluloses (13.62%), and lignin (20.53%) at a moisture content of 7.9% (w.b). Specific heat capacity of flax shives changed from 1.5 to 2.7 kJ/ (kg °C) when the moisture content was increased from 8 to14% (w.b.) and temperature from 15 to 80°C. The shives had the combustion energy of 17.67 MJ/kg at a moisture content of 8.1% (w.b.).<p> The smallest screen size (2.4 mm) resulted in the highest unit density (1010 kg/m3) and the highest durability (88%) in the pellets produced by the single-pelleting equipment. The change in length of pellets produced by the pilot-scale mill increased as canola meal increased from 18 to 24% at the highest moisture content (%). The pellets were more stable at the highest moisture content when the lowest canola meal used. The addition of 18% canola meal and grinds from a screen size of 6.4 mm produced the highest unit density in the pellets at all moisture levels. The highest bulk density (682 kg/m3) was obtained from shive mixtures with 18% canola meal and a moisture content of 8%. The highest hardness and durability were found for the shive pellets that were produced with 18% canola meal at a moisture content of 14% (w.b). Pellets that were produced at a moisture content of 14% (w.b) resulted in the lowest percentage of moisture absorption. The inclusion of the canola meal in the shive mixture resulted in an increase in the combustion energy of the pellets because of the fat content in the binder. The two levels of canola meal for shive pellets had essentially the same level of emissions. However, there were significant differences between shive pellets and commercial wood pellets in the level of the emissions. Lower amounts of methane (1.29 ppm) and oxygen (164.3 ppt) were found for flax shive pellets than of methane (1.63 ppm) and oxygen (176.6 ppt) in commercial wood pellets.<p> In short, pelleting of flax shives into fuel pellets improved the handling characteristics, increased bulk density and energy content. Fuel pellets made from flax shives had less emission of methane and oxygen from combustion when compared to commercial wood pellets.

As demand for renewable energy is increasing rapidly, the market for biomass pellets is expected to continue to grow in the near future. Most of the new raw materials that are discussed for pellet production have one thing in common; the production costs will increase compared to using traditional raw materials such as sawdust and planer shavings. The aim of this thesis is to investigate to what degree increased use of new raw materials for pellet production will affect the general pellet prices in Sweden and to survey what plans Swedish pellet producers have concerning new raw materials. To investigate the raw material situation of the Swedish pellet producers an industry survey was performed. Literature studies were also made on previous research in the subject field. Calculations of the production costs for pellets were done for the raw materials sawdust, wet sawmill chips and energy wood respectively.                 New raw materials are already used by the large-scale pellet producers in Sweden. It is mainly the large-scale producers that have started to use new raw materials such as energy wood, wet sawmill chips and dry chips. Around 65% of the respondents of the survey were planning for new raw materials. Most commonly planned for was energy wood. Most of the pellet producers in the survey were planning for raw materials that give high quality pellets. The minimum price for pellets is in the long run set by the production costs. The raw material costs are the most important part of the production costs and according to results from the survey they also affect the pellet prices most. For pellets made of sawdust the raw material costs were typically 2/3 of the total production costs in 2009. In calculations of production costs, wet sawmill chips resulted in a decreased cost by 4% compared to sawdust, mainly because of less expensive raw material. Energy wood also resulted in decreased production costs by 4% compared to sawdust, assuming that the thermal energy needed for drying could be entirely produced with the bark from the debarking process. Both energy wood and wet sawmill chips could hence decrease the production costs and thereby the price for pellets. Even though there is a much greater maximum pellet production potential for wet sawmill chips than for sawdust the amounts of available raw material will, among other factors, depend on the development in the pulp industry.

Flax shives are a source of abundant biomass from renewable sources. They are considered to be environmentally benign and have a high-energy content for heating and generation of electricity, but only after being processed into pellets. Pelleting of the shives was done by using the single-pelleter and pilot-scale mill. The effect of grinding with screens of 2.4, 3.2, and 6.4 mm on unit density and durability was conducted with a completely randomized design using shives from Biofibre Industries Inc., Canora, SK. The central composite face-centered design with 3 levels of lower grade canola meal used as a binder (18, 21, and 24%), moisture content (8, 11, and 14% (w.b)), and hammer mill screen size (3.2, 4.8, and 6.4 mm) was used to determine the effects of these three factors on the properties of fuel pellets made from shives obtained from Biolin Research Inc., Saskatoon, SK. The initial moisture content of coarse flax shives from both sources was about 10.5% wet basis (w.b.). The moisture content of flax shive grinds ranged from 9.6 to 10.5% (w.b.) after grinding, using the smaller screens for the Biofibre material, while the moisture content ranged from 7.9 to 8.6% (w.b.) for shives from Biolin. Also, smaller screen size reduced the geometric mean particle size for shives from both sources. The use of the smaller hammer mill screen resulted in an increase in both bulk and particle density of shives. There was a decrease in coefficient of the internal friction of shives from 0.20 to 0.14 and an increase in a cohesion of shives from 2.18 to 3.83 kPa when the screen size decreased from 6.4 to 3.2 mm. The flax shives contained cellulose (53.27%), hemicelluloses (13.62%), and lignin (20.53%) at a moisture content of 7.9% (w.b). Specific heat capacity of flax shives changed from 1.5 to 2.7 kJ/ (kg °C) when the moisture content was increased from 8 to14% (w.b.) and temperature from 15 to 80°C. The shives had the combustion energy of 17.67 MJ/kg at a moisture content of 8.1% (w.b.).<p> The smallest screen size (2.4 mm) resulted in the highest unit density (1010 kg/m3) and the highest durability (88%) in the pellets produced by the single-pelleting equipment. The change in length of pellets produced by the pilot-scale mill increased as canola meal increased from 18 to 24% at the highest moisture content (%). The pellets were more stable at the highest moisture content when the lowest canola meal used. The addition of 18% canola meal and grinds from a screen size of 6.4 mm produced the highest unit density in the pellets at all moisture levels. The highest bulk density (682 kg/m3) was obtained from shive mixtures with 18% canola meal and a moisture content of 8%. The highest hardness and durability were found for the shive pellets that were produced with 18% canola meal at a moisture content of 14% (w.b). Pellets that were produced at a moisture content of 14% (w.b) resulted in the lowest percentage of moisture absorption. The inclusion of the canola meal in the shive mixture resulted in an increase in the combustion energy of the pellets because of the fat content in the binder. The two levels of canola meal for shive pellets had essentially the same level of emissions. However, there were significant differences between shive pellets and commercial wood pellets in the level of the emissions. Lower amounts of methane (1.29 ppm) and oxygen (164.3 ppt) were found for flax shive pellets than of methane (1.63 ppm) and oxygen (176.6 ppt) in commercial wood pellets.<p> In short, pelleting of flax shives into fuel pellets improved the handling characteristics, increased bulk density and energy content. Fuel pellets made from flax shives had less emission of methane and oxygen from combustion when compared to commercial wood pellets.

Comprehensive analyses are conducted of the holistic farm production-harvesting-transporting-pre-refinery storage supply chain paradigm which represents the totality of important issues affecting the conversion facility front-gate costs of delivered biomass feedstocks. Targeting the Middle Gulf Coast, Edna-Ganado, Texas area, mathematical programming in the form of a cost-minimization linear programming model(Sorghasaurus) is used to assess the financial and economic logistics costs for supplying a hypothetical 30-million gallon conversion facility with high-energy sorghum (HES) and switchgrass (SG) cellulosic biomass feedstock for a 12-month period on a sustainable basis. A corporate biomass feedstock farming entity business organization structure is assumed. Because SG acreage was constrained in the analysis, both HES and SG are in the optimal baseline solution, with the logistics supply chain costs (to the front gate of the conversion facility) totaling $53.60 million on 36,845 acres of HES and 37,225 acres of SG (total farm acreage is 187,760 acres, including HES rotation acres), i.e., $723.67 per harvested acre, $1.7867 per gallon of biofuel produced not including any conversion costs, and $134.01 per dry ton of the requisite 400,000 tons of biomass feedstock. Several sensitivity scenario analyses were conducted, revealing a potential range in these estimates of $84.75-$261.52 per dry ton of biomass feedstock and $1.1300-$3.4870 per gallon of biofuel. These results are predicated on simultaneous consideration of capital and operating costs, trafficable days, timing of operations, machinery and labor constraints, and seasonal harvested biomass feedstock yield relationships. The enhanced accuracy of a comprehensive, detailed analysis as opposed to simplistic approach of extrapolating from crop enterprise budgets are demonstrated. It appears, with the current state of technology, it is uneconomical to produce cellulosic biomass feedstocks in the Middle Gulf Coast, Edna-Ganado, Texas area. That is, the costs estimated in this research for delivering biomass feedstocks to the frontgate of a cellulosic facility are much higher than the $35 per ton the Department of Energy suggests is needed. The several sensitivity scenarios evaluated in this thesis research provides insights in regards to needed degrees of advancements required to enhance the potential economic competitiveness of biomass feedstock logistics in this area.

Bioenergy production from forest resources offers opportunities to reduce greenhouse gas (GHG) emissions associated with fossil fuel use, reduce non-renewable energy consumption, and provide investment and employment in the forestry sector. These opportunities, however, must be considered within the broader contexts of forest systems. Of particular interest is how bioenergy opportunities impact carbon storage within the forest. This thesis develops a method to integrate life cycle assessment and forest carbon analysis approaches to quantify the total GHG emissions associated with forest bioenergy. Bioenergy production and utilization decisions are then investigated to evaluate opportunities to increase GHG mitigation performance. An accounting method is developed to evaluate the impact of emissions timing on the cost-effectiveness of GHG emissions reductions from biomass-based electricity generation. Applying the integrated life cycle assessment/forest carbon analysis method to a case study of forest bioenergy production in Ontario reveals significant reductions in forest carbon associated with bioenergy production. Wood pellet production from standing trees or harvest residues (displacing coal in electricity generation) would increase total GHG emissions over periods of approximately 40 and 15 years, respectively. Ethanol production (displacing gasoline) would increase GHG emissions throughout the 100-year model period if produced from standing trees; emissions would increase over a period of approximately75 years if produced from harvest residues. Strategic ethanol production decisions (e.g., process energy source, co-location with other processes, co-product selection) can improve GHG mitigation. Co-production of biomass pellets with ethanol performs best among co-product options in terms of GHG emissions; co-location with facilities exporting excess steam and biomass-based electricity further increases GHG mitigation performance. Delayed GHG reductions due to forest carbon impacts the cost of GHG emissions reductions associated with electricity production from forest biomass. Cost-effectiveness is heavily dependent on the time horizon over which global warming impacts are measured and influences the ranking of biomass electricity pathways (biomass co-firing is the most cost-effective pathway between 2020 and 2100; biomass cogeneration is the most cost-effective pathway beyond year 2100). The accounting tools and methods developed within this thesis will to help inform decision-makers in the responsible development of forest bioenergy opportunities and associated policies.

Bioenergy production from forest resources offers opportunities to reduce greenhouse gas (GHG) emissions associated with fossil fuel use, reduce non-renewable energy consumption, and provide investment and employment in the forestry sector. These opportunities, however, must be considered within the broader contexts of forest systems. Of particular interest is how bioenergy opportunities impact carbon storage within the forest. This thesis develops a method to integrate life cycle assessment and forest carbon analysis approaches to quantify the total GHG emissions associated with forest bioenergy. Bioenergy production and utilization decisions are then investigated to evaluate opportunities to increase GHG mitigation performance. An accounting method is developed to evaluate the impact of emissions timing on the cost-effectiveness of GHG emissions reductions from biomass-based electricity generation. Applying the integrated life cycle assessment/forest carbon analysis method to a case study of forest bioenergy production in Ontario reveals significant reductions in forest carbon associated with bioenergy production. Wood pellet production from standing trees or harvest residues (displacing coal in electricity generation) would increase total GHG emissions over periods of approximately 40 and 15 years, respectively. Ethanol production (displacing gasoline) would increase GHG emissions throughout the 100-year model period if produced from standing trees; emissions would increase over a period of approximately75 years if produced from harvest residues. Strategic ethanol production decisions (e.g., process energy source, co-location with other processes, co-product selection) can improve GHG mitigation. Co-production of biomass pellets with ethanol performs best among co-product options in terms of GHG emissions; co-location with facilities exporting excess steam and biomass-based electricity further increases GHG mitigation performance. Delayed GHG reductions due to forest carbon impacts the cost of GHG emissions reductions associated with electricity production from forest biomass. Cost-effectiveness is heavily dependent on the time horizon over which global warming impacts are measured and influences the ranking of biomass electricity pathways (biomass co-firing is the most cost-effective pathway between 2020 and 2100; biomass cogeneration is the most cost-effective pathway beyond year 2100). The accounting tools and methods developed within this thesis will to help inform decision-makers in the responsible development of forest bioenergy opportunities and associated policies.

Currently, only 2.8% of total energy use in the world is renewable energy. As a climate target in 2020, the European Union has set a goal of increasing the renewable energy to 20%. Renewable energy includes biofuel such as pellets.   Pellets use has already increased significantly and several large production units have been built in recent years. To achieve a competitive pellet, production must be improved in terms of quality, environmental impact, and electricity consumption. Adding additives can improve pellets strength, reduce CO2eq emissions and reduce energy consumption.   The purpose is to investigate how different percentages of additive affect pellets to achieve a more sustainable and competitive biofuel.   In the quality analysis where sustainability and hardness were investigated, oxidized corn starch showed the best result where sustainability increased from 94.8% to 97.86%. The hardness varied greatly from pellets to pellets from the same sample. Since the hardness varied so widely, it was impossible to say which sample who had the highest hardness. On the other hand, it is concluded that the oxidized cornstarch samples received higher hardness than the zero sample.   In the environmental section, CO2equivalents for pellet production were investigated in Sweden, OECD member countries and non-OECD member countries in Europe. In Sweden and in OECD member countries, pellets production did not reduce the CO2eq emissions with any added additive. In non-OECD member countries, wheat starch was the best additive and reduced CO2eq emissions by 2.4%.   The energy consumption in the pellet press was also analyzed and the results showed that all additives reduced energy consumption. The best additive in this study was wheat starch, which reduced electricity consumption by 3.9%.

Världens ökande energibehov och önskan om att minimera konsekvenserna av klimatförändringen har gjort att flera miljömål tagits fram både på nationella och internationella nivåer. Mycket resurser läggs ner på att utveckla nuvarande förnyelsebara energikällor och hitta nya alternativ till de fossila bränslena. En förnyelsebar energiresurs är biogas. Biogas bildas vid nedbrytning av organiskt material och bildar koldioxid och energirik metangas.   Detta examensarbete har fokuserat på två områden, det första att undersöka metanproduktionen i en samrötningsprocess med ensilage av våtmarksgräs och substrat från Mosseruds biogasanläggning. Mosserud ligger några km väster om Karlskoga och idag behandlas i huvudsak insamlat matavfall, nötflytgödsel och vallgröda. Våtmarksgräset kommer från Brosjö området utanför Säffle. Under 2010-2014 ingick Brosjö i ett EU projekt som främjar mångfaldignatur och utsatta djurarter, vilket bland annat har gett ett ekonomisk stöd i att skörda gräset. Det skördade gräset har idag ingen användning, men skulle kunna passa i en rötprocess.    Det andra området var att jämföra resultaten med tidigare rapporter inom rötning samt användandet av våtmarksgräs. Arbetet av Neldorin (2015) där en studie om substratmixen vid Mosserud gjordes, låg som grund för hur biogasproduktionen ser ut på Mosseruds anläggning idag och jämfördes med metanproduktionen i denna studie. Den andra rapporten studerade våtmarksgräs som additiv i pellets. Där Henriksson (2016) hade fokus på energiåtgången av pelleteringen när våtmarksgräs från Brosjö användes.      Rötningsförsöken skedde på Karlstads universitet, där rötningen var en semi- kontinuerlig våt process med mesofila förhållanden. Där inmatning och uttag av gas gjordes en gång om dagen, vilket var samma uppställning som Neldorin (2015) använde. Försöket varade under 10 veckors tid och 2 olika substratblandningar användes; en med 30 % gräs 70 % matavfall och en med 15 % gräs 85 % matavfall. Resultatet gav att rötningen med substratblandningen 30 % gräs 70 % substrat från Mosserud var att föredra. Den specifika metanproduktionen var 0,300 och 0,350 Nm3/kg VS/dag, vilket var mindre än de värde som kommit fram från Mosserud 0,352 Nm3/kg VS/dag. Den totala produktionen av metangas kunde ökas mellan 1,5 - 2,6 % då mer substrat fanns tillgängligt.   Våtmarksgräset var bättre att använda till rötning än till pelletering då rötning kunde öka den totala metanproduktionen, medans pelleten som tillverkades inte uppfyllde kraven på hållfasthet, bulkdensitet och andel finfraktion. De problem som är kopplade till att använda gräs i rötning är slambildning i reaktortanken och processen stabilitet under en längre tid, då pH värdet sjönk av ansamling av VFA. / The worlds increasing need for energy and the desire to minimize the consequences of climate change have led to several environmental goals at both national and international levels. Many resources are spent on developing the current renewable energy sources and to find new alternatives. One of the renewable energy resources is biogas. Biogas is formed when organic matter is decomposed which forms carbon dioxide and energy rich methane gas.   This master's thesis has focused on two areas, the first to examine methane production in a co- digestion process with silage of wetlands grass and food waste from Mosserud biogas plant. Mosserud is located a couple of kilometers west of Karlskoga city. Today the plant mainly uses food waste, manure and ley crops. The wetland grass originates from an area outside of Säffle called Brosjö. In 2010-2014 the Brosjö area was a part of an EU project that promotes bio diversity and threaten animal species, which . Due to this project the harvesting of grass has been made easier and has no use today, but could fit in an anaerobic digestion process.   The second area was to compare the results with earlier reports on anaerobic digestion and the use of wetland grass. Neldorin (2015),vconducted a study of the substrate mix at Mosserud, whihc lays as a basis for biogas production from Mosserud today compared to the results of this study. The second report studied wetland grass as an additive in pellets. Where Henriksson (2016) had focus on energy consumptions during production of pellets when using wetland grass from Brosjö.   The laboratory study was made at Karlstad University, the study was a semi continuous wet anaerobic process with mesophilic conditions. Feeding and withdrawal of gas was made once a day, using the same lab line up as Neldorin (2015) did. The experiment lasted 10 weeks and 2 different substrate mixtures were used; one with 30% grass 70% food waste and one with 15% grass 85% food waste. The result showed that digestion with 30 % grass mix was preferred. The specific methane production was 0.300 and 0.350 Nm3 / kg VS / day, which was less than those obtained from Mosserud at 0,352 Nm3 / kg VS / day. The total production of methane gas could be increased between 1.5 - 2.6% as there was access to more substrates.   Wetland grass was better used for digestion than pelleting as it could increase the total methane production, while the pellets produced did not meet the requirements of strength, bulk density and fractional fineness. The problems associated with using grass in digestion are sludge formation in the reactor tank and process stability for a long time, when the pH value fell by the accumulation of VFA.

The aim of this thesis is to enhance heterocyst-based hydrogen production inNostoc punctiforme ATCC 29133. We envision to do so by finely regulatingthe ratio of heterocyst in order to optimize the filament energy balance. Wehereby report the development of an optogenetic synthetic switch basedon the native PcpeC promoter. The optogenetic switch featured a 24-folddynamic range when measuring reporter sfGFP fluorescence. Such a geneticgate was conceived to artificially drive the expression of hetR, the masterregulator of heterocyst development. We achieved to induce enhancedheterocyst differentiation in the presence of ammonia only by changing thechromatic properties of the light source. Thus, the natural cell developmentregulation was substituted by effectively introducing a full person-drivencontrol over the process.