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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Fertilization of willow bioenergy cropping systems in Saskatchewan, Canada

Konecsni, Sheala Marie 30 August 2010 (has links)
The detrimental effects of climate change and the threat of diminishing fossil fuel reserves is forcing society to search for renewable sources of energy. Energy can be derived from the biomass of plant material by co-fire combustion with coal or on its own for the production of electricity. Energy can also be created by converting the plant biomass into ethanol, a gasoline substitute. When converted into bioenergy, plant biomass from Short Rotation Woody Crop (SRWC) systems has the potential to offset the use of fossil fuels if the yields can be maintained at profitable levels. The effect of first year application of nitrogen (N) fertilizer on willow biomass production in a SRWC system is not well understood. Using field and growth chamber studies, the objectives of this study were to 1) determine biomass production in the growing seasons following a single application of N fertilizer in the year of planting, 2) determine the N recovery for five willow clones using a 15N tracer, and 3) evaluate the effects of various types and rates of fertilizers on biomass production. Objectives 1 and 2 were addressed in a field fertilization study conducted on agricultural lands in the Moist Mixed Grassland ecozone and at tree nursery in the Boreal Transition ecozone. Willow cuttings were planted and fertilized with 100 kg N ha-1 of granular ammonium nitrate. Twelve trees were fertilized with 5 kg N ha-1 of double 15N-labeled ammonium nitrate and 95 kg N ha-1 of granular ammonium nitrate. In the first growing season trees were browsed to a uniform height making biomass measurements unrepresentative of production potential. Annual shoot biomass production in the second year, however, was 0.39 to 2.0 Mg ha-1 and was not found to be significantly different between fertilizer treatments. Nitrogen recovery by entire trees ranged from 2.87 to 10.6 % in the first growing season and 0.39 to 2.95 % in the second growing season. Objective three was addressed in a growth chamber study. Willow cuttings were planted in pots and fertilized with 0, 50, 100 and 200 kg N ha-1 of granular ammonium nitrate and 100 kg N ha-1 of composted cattle manure. After a 90 day growth period shoot biomass production was significantly greater on the Prince Albert soil (1.28 to 5.34 g tree-1) than on the Saskatoon soil (1.18 to 3.59 g tree-1). No consistent trend between fertilizer treatments was observed. Further exploration into fertilization of willow SRWC systems should consider the application of multiple nutrient fertilizer blends, various rates and year of application to gain a better understanding of nutrient requirements of willow for the entire growth period.
12

The usability of switchgrass, rice straw, and logging residue as feedstocks for power generation in East Texas

Hong, Sung Wook 17 September 2007 (has links)
This thesis examines the economic implications of using agriculturally based feedstock for bio-energy production in East Texas. Specifically I examined the use of switchgrass, rice straw, and logging residue as a feedstock for electrical power generation in East Texas replacing coal. To examine the effects of such a substitution, an environmental bio-complexity approach is used to analyze the interactions of agricultural, technological, economic, and environmental factors. In particular, lifecycle analysis (LCA) and Cost-Benefit analysis is used. The results show that as we use more bio-energy for power generation, we will get less Greenhouse Gas (GHG) emission, which will be an environmental benefit in the long run. The main problem is that cost increases. Current biomass feedstock production costs are generally too high for biomass feedstock to replace coal in power generation. However I find that GHG offset prices can make biomass economically attractive. In particular GHG offset prices and forgiveness for the emissions from combustion based on photosynthetic absorption would raise the price people would be willing to pay for biomass feedstock making it competitive.
13

Biorefinery feedstock availability and price variability : case study of the Peace River region, Alberta

Stephen, James Duncan 11 1900 (has links)
The purpose of this research was to quantify feedstock supply risk over the lifetime of an agricultural residue-based (straw and chaff) biorefinery and to determine the range of delivered prices. The Peace River region of Alberta was used as a case study for analysis, with a geographic information system utilized for data analysis. Inter-year availability of crop residues was highly variable over the 20 year period under study, which created significant differences in the delivered price of feedstock between minimum, average, and maximum availability scenarios. At the four primary study sites (Fahler, Grimshaw, Peace River, and Sexsmith), the range was from double the average availability for the maximum scenario to zero biomass available for the minimum scenario. Biomass availability is a function of grain yield, the biomass to grain ratio, the cropping frequency, and residue retention rate used to ensure future crop productivity. Using minimum, average, and maximum supply scenarios, delivered price was determined using the dynamic (time-dependent) Integrated Biomass Supply Analysis and Logistics (IBSAL) simulation model. Five biorefinery capacities, ranging from 50,000 to 500,000 tonnes of feedstock per year, were analyzed. Since no biomass was available to model in true minimum years, a simulated minimum of half the average availability was used. Delivered cost, including harvest and transportation, for the 50,000 t plant ranged from $24.01 t-1 for the maximum availability scenario at the Sexsmith site to $42.63 t-1 for the simulated minimum scenario at the Fahler site. The range for the 500,000 t plant at the Sexsmith site was $41.78 for the maximum availability and $70.98 for the simulated minimum availability. As no biomass is available (and hence the true cost is unknown) in some years, storage strategies must be implemented and alternate feedstock sources identified to supply biorefineries in low-yield years. Since feedstock cost is a large component of total operating cost of a biorefinery, feedstock supply variability and delivered cost inconsistency should be primary decision criteria for any future biorefinery projects.
14

EFFECT OF NITROGEN FERTILIZER ON NITROUS OXIDE EMISSIONS FROM THE SOIL FOR TWO POTENTIAL ENERGY CROPS AND THE RELATIVE GREENHOUSE GAS EMISSIONS

Wile, Adam 10 August 2010 (has links)
The benefits from energy crops are debated. This two-year study was designed to investigate nitrous oxide (N2O) emissions, yield and ash content from fertilized bioenergy crops switchgrass and reed canary grass with and without inter-seeded red clover. Overall, N2O emissions were less than 1kg N2O-N ha-1 in the first year and around 100g N2O-N ha-1 in the second year with a N fertilizer effect in the first year. Plots inter-seeded with red clover received half the N fertilizer of pure grass stands but showed no difference in N2O emissions compared to the pure stands and also had higher ash content. Cumulative soil mineral N responded to N fertilizer addition but no effect of crop type was evident in 2008 and 2009. Yields for both crops were unresponsive to N fertilizer addition while pure switchgrass yielded higher than inter-seeded switchgrass in 2008 and switchgrass had lower ash content.
15

THE ECONOMIC FEASIBILITY OF BIOENERGY PRODUCTION FROM MISCANTHUS FOR THE ONTARIO GREENHOUSE INDUSTRY

Virani, Tasneem 07 June 2011 (has links)
This thesis investigates the cost of producing miscanthus in Ontario as an energy crop for the Ontario greenhouse industry. To determine the breakeven price of growing miscanthus an enterprise budget was developed and applied to three different life cycle scenarios to determine the effect of stand life on the breakeven price. The base case breakeven price of producing miscanthus ranged from $74.74/t to $80.22/t. Sensitivity analysis was conducted to assess the effect of assumptions (stand yield, rhizome cost, harvest method and discount rate) on the breakeven price. Price of energy from miscanthus ranged from $2.87/GJ to $8.63/GJ with an average price of $5.51/GJ. The Ontario greenhouse industry`s willingness to pay for bioenergy from miscanthus is based on the prices of fuels currently in use. Ontario farmer‘s willingness to produce miscanthus is based on its profitability compared to other crops and the time it takes to pay off the initial investment.
16

Exploring Tools to Develop the Bioeconomy in Eastern Ontario

Wood, Trista 03 October 2012 (has links)
The bioeconomy, which would utilize biomass resources for the renewable production of energy, fuels, and products, has been proposed as a mechanism by which Ontario’s resource-dependent communities might be revitalized. This thesis applies a knowledge economy framework to the establishment of a bioeconomy, with a strong focus on bioenergy as a first step, in Kingston and the surrounding region. The knowledge economy approach was examined in relation to other measures of sustainability and security. A series of 25 expert interviews informed an analysis of strengths, weaknesses, opportunities and threats on the topic of the knowledge-based bioeconomy study region. The ability of the knowledge-based approach to assess the requirements of the bioeconomy was then evaluated using a statistical assessment of the study region based on Florida’s ‘creative economy’ framework, and this assessment was compared to key factors noted in the SWOT analysis. Research findings indicate that basic necessities such as feedstock, technology and transportation routes are likely available across the study region. However, key elements of the knowledge economy are absent particularly human resources in the ‘creative’ class. The knowledge-based approach is not particularly well suited to capturing all aspects of the bioeconomy, as it overlooks physical geographical features, which may be better measured by other tools. More focused policy with regard to renewable energy locally, provincially and nationally is seen to be important for advancing the bioeconomy. Acting on opportunities and using regional strengths will insure a successful implementation of a knowledge-based bioeconomy that will provide the benefits of economic growth associated with knowledge economies. / Thesis (Master, Geography) -- Queen's University, 2012-09-28 14:01:25.454
17

Isolation and characterisation of cellulolytic bacteria from a cattle waste digester

Sharma, V. K. January 1983 (has links)
No description available.
18

Feedstock Logistics of a Mobile Pyrolysis System and Assessment of Soil Loss Due to Biomass Removal for Bioenergy Production

Bumguardner, Marisa 2011 August 1900 (has links)
The purpose of this study was to assess feedstock logistics for a mobile pyrolysis system and to quantify the amount of soil loss caused by harvesting agricultural feedstocks for bioenergy production. The analysis of feedstock logistics was conducted using ArcGIS with the Network Analyst extension and model builder. A square grid methodology was used to determine biomass availability of corn stover and bioenergy sorghum in Texas. The SWAT model was used to quantify soil erosion losses in surface runoff caused by sorghum residue removal for bioenergy production in the Oso Creek Watershed in Nueces County. The model simulated the removal of 25, 50, 75, and 100 percent residue removal. The WEPS model was used to quantify wind erosion soil loss caused by corn stover removal in Dallam County. Nine simulations were run estimating soil loss for corn stover removal rates of 0 percent to 50 percent. The results of the SWAT and WEPS analyses were compared to the NRCS tolerable soil loss limit of 5 tons/acre/year for both study areas. The GIS analysis determined the optimum route distances between mobile unit sites were 2.07 to 58.02 km for corn and 1.95 to 60.36 km for sorghum. The optimum routes from the mobile pyrolysis sites and the closest refineries were 49.50 to 187.18 km for corn and 7.00 to 220.11 km for sorghum. These results were used as input to a separate bioenergy economic model. The SWAT analysis found that maximum soil loss (1.24 tons/acre) occurred during the final year of the simulation where 100 percent of the sorghum residue was removed. The WEPS analysis determined that at 30 percent removal the amount of soil loss starts to increase exponentially with increasing residue removal and exceeds the tolerable soil loss limit. Limited harvesting of biomass for bioenergy production will be required to protect crop and soil productivity ensuring a sustainable biomass source.
19

Biorefinery feedstock availability and price variability : case study of the Peace River region, Alberta

Stephen, James Duncan 11 1900 (has links)
The purpose of this research was to quantify feedstock supply risk over the lifetime of an agricultural residue-based (straw and chaff) biorefinery and to determine the range of delivered prices. The Peace River region of Alberta was used as a case study for analysis, with a geographic information system utilized for data analysis. Inter-year availability of crop residues was highly variable over the 20 year period under study, which created significant differences in the delivered price of feedstock between minimum, average, and maximum availability scenarios. At the four primary study sites (Fahler, Grimshaw, Peace River, and Sexsmith), the range was from double the average availability for the maximum scenario to zero biomass available for the minimum scenario. Biomass availability is a function of grain yield, the biomass to grain ratio, the cropping frequency, and residue retention rate used to ensure future crop productivity. Using minimum, average, and maximum supply scenarios, delivered price was determined using the dynamic (time-dependent) Integrated Biomass Supply Analysis and Logistics (IBSAL) simulation model. Five biorefinery capacities, ranging from 50,000 to 500,000 tonnes of feedstock per year, were analyzed. Since no biomass was available to model in true minimum years, a simulated minimum of half the average availability was used. Delivered cost, including harvest and transportation, for the 50,000 t plant ranged from $24.01 t-1 for the maximum availability scenario at the Sexsmith site to $42.63 t-1 for the simulated minimum scenario at the Fahler site. The range for the 500,000 t plant at the Sexsmith site was $41.78 for the maximum availability and $70.98 for the simulated minimum availability. As no biomass is available (and hence the true cost is unknown) in some years, storage strategies must be implemented and alternate feedstock sources identified to supply biorefineries in low-yield years. Since feedstock cost is a large component of total operating cost of a biorefinery, feedstock supply variability and delivered cost inconsistency should be primary decision criteria for any future biorefinery projects.
20

Biorefinery feedstock availability and price variability : case study of the Peace River region, Alberta

Stephen, James Duncan 11 1900 (has links)
The purpose of this research was to quantify feedstock supply risk over the lifetime of an agricultural residue-based (straw and chaff) biorefinery and to determine the range of delivered prices. The Peace River region of Alberta was used as a case study for analysis, with a geographic information system utilized for data analysis. Inter-year availability of crop residues was highly variable over the 20 year period under study, which created significant differences in the delivered price of feedstock between minimum, average, and maximum availability scenarios. At the four primary study sites (Fahler, Grimshaw, Peace River, and Sexsmith), the range was from double the average availability for the maximum scenario to zero biomass available for the minimum scenario. Biomass availability is a function of grain yield, the biomass to grain ratio, the cropping frequency, and residue retention rate used to ensure future crop productivity. Using minimum, average, and maximum supply scenarios, delivered price was determined using the dynamic (time-dependent) Integrated Biomass Supply Analysis and Logistics (IBSAL) simulation model. Five biorefinery capacities, ranging from 50,000 to 500,000 tonnes of feedstock per year, were analyzed. Since no biomass was available to model in true minimum years, a simulated minimum of half the average availability was used. Delivered cost, including harvest and transportation, for the 50,000 t plant ranged from $24.01 t-1 for the maximum availability scenario at the Sexsmith site to $42.63 t-1 for the simulated minimum scenario at the Fahler site. The range for the 500,000 t plant at the Sexsmith site was $41.78 for the maximum availability and $70.98 for the simulated minimum availability. As no biomass is available (and hence the true cost is unknown) in some years, storage strategies must be implemented and alternate feedstock sources identified to supply biorefineries in low-yield years. Since feedstock cost is a large component of total operating cost of a biorefinery, feedstock supply variability and delivered cost inconsistency should be primary decision criteria for any future biorefinery projects. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

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