The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Karen N. Finney - One of the best experts on this subject based on the ideXlab platform.
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fuel pelletization with a binder part i identification of a suitable binder for Spent Mushroom Compost coal tailing pellets
Energy & Fuels, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, Jim SwithenbankAbstract:Spent Mushroom Compost and coal tailings are wastes that could be used as energy sources, through combustion in a fluidized-bed. Our previous pelletization studies produced a denser, yet friable fuel, which produced dust on transport, handling, and feeding. Thus, a suitable binder for these materials was required to enhance pellet properties. Inorganic (caustic soda) and organic (starch) binders were selected for a range of tests. Pelletization at elevated temperatures was also assessed to evaluate the softening of any lignin present in the straw component of the Mushroom Compost. Small amounts (up to 1 wt %) of both binders increased pellet tensile strength, where starch had more pronounced impacts, doubling the tensile strength to 411 kPa. Pelletization at elevated temperatures (45−75 °C), however, improved overall pellet quality more significantly, increasing the tensile strength to over 600 kPa, although additional temperature increases (up to 125 °C) did not result in further improvements. Whether a ...
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fuel pelletization with a binder part ii the impacts of binders on the combustion of Spent Mushroom Compost coal tailing pellets
Energy & Fuels, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, J SwithenbankAbstract:Various additives, namely, starch and caustic soda, have been identified in the previous paper as binders to improve the quality of fuel pellets made from two wastes—Spent Mushroom Compost and coal tailings. Combustion tests using these pellets in a small, laboratory-scale fluidized-bed were performed to evaluate the impacts these binders had on the efficiency, emissions, and ash properties. Thermal treatment revealed that combustion of these pellets with either binder was fairly comparable to the control case, where no binder was used, in terms of the temperatures achieved and gaseous emission concentrations (including acid gas species). The combustion efficiencies were lower (88.7% compared to 95.0%), possibly due to a modification in particle structure, however there was less combustible material remaining in the flyash. The use of caustic soda increased the likelihood of slagging/fouling within the system, due to the greater concentration of alkali metal oxides in the flyash. The ash fusion temperatur...
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combustion of Spent Mushroom Compost and coal tailing pellets in a fluidised bed
Renewable Energy, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, Jim SwithenbankAbstract:Abstract Previous investigations found that fluidised-bed combustion of Spent Mushroom Compost–coal tailing pellets was preferred for these high ash content fuels. This paper considers the combustion tests carried out on these wastes in a laboratory-scale fluidised-bed, where parameters, including the pellet feedrate, primary/fluidising air flowrate and bed depth, were investigated. Based on the minimum air ratio of 2.5 required to achieve high combustion efficiencies of around 97%, the optimum operating conditions for the combustor employed were a pellet feedrate of 3.25 kg/h (180 kg/m2h) and a total air flowrate of 650 kg/m2h. A lower sand bed depth of 0.22 m was also deemed beneficial, as deeper beds resulted in slugging and noticeable reductions in combustion efficiency. Acid gas emissions (NOx, SOx and HCl) were found in limited concentrations, as species remained primarily as inorganic compounds in the flyash. Some N2O is thought to have formed, as fluidised-bed combustors are particularly prone to this. The alkali index of the ash suggests probable fouling/slagging in the system. For industrial-scale combustion of these wastes, the combustion efficiency could be improved by the presence of secondary air jets to aid turbulent mixing.
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the reuse of Spent Mushroom Compost and coal tailings for energy recovery comparison of thermal treatment technologies
Bioresource Technology, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, Changkook Ryu, Jim SwithenbankAbstract:Thermal treatment technologies were compared to determine an appropriate method of recovering energy from two wastes - Spent Mushroom Compost and coal tailings. The raw Compost and pellets of these wastes were combusted in a fluidised-bed and a packed-bed, and contrasted to pyrolysis and gasification. Quantitative combustion parameters were compared to assess the differences in efficiency between the technologies. Fluidised-bed combustion was more efficient than the packed-bed in both instances and pellet combustion was superior to that of the Compost alone. Acid gas emissions (NO(x), SO(x) and HCl) were minimal for the fluidised-bed, thus little gas cleaning would be required. The fuels' high ash content (34%) also suggests fluidised-bed combustion would be preferred. The Alkali Index of the ash indicates the possibility of fouling/slagging within the system, caused by the presence of alkali metal oxides. Pyrolysis produced a range of low-calorific value-products, while gasification was not successful.
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pelletised fuel production from coal tailings and Spent Mushroom Compost part i identification of pelletisation parameters
Fuel Processing Technology, 2008Co-Authors: Changkook Ryu, Karen N. Finney, Vida N. Sharifi, J SwithenbankAbstract:Abstract This study investigates the technology of manufacturing pellet blends for energy production from two discarded materials in industry. Coal tailings material is the fine discard produced as a result of coal cleaning. Although it still has a significantly high calorific value, over a million tonnes of coal tailings are deposited in lagoons every year in the UK alone. Spent Mushroom Compost (SMC) consists of fibrous Compost substrate and a wet casing layer used during Mushroom production. In the form of pellets, these materials become more homogeneous, easily stored and transported, and suitable for use in power plants or gasifiers. The characterisation of the fuel properties shows that the two materials have a complimentary status for pelletisation and energy production in terms of particle types, carbon source, calorific value and volatile matter content. Pelletisation tests were carried out using a small compression rig for various pressures, moisture contents and mixture compositions. The quality of the pellets was assessed using density, swelling, tensile strength and durability. It was necessary to keep the moisture contents for coal tailings at about 10% and for SMC at 20% before pelletisation in order to maximise the bonding strength of the originally wet materials. Pressures above 6000 psi did not produce noticeably denser or stronger pellets. The pellets from coal tailings and SMC blends had a tensile strength proportional to the SMC fraction. The SMC pellets were more durable than the coal tailing pellets due to the intertwined Compost fibres. It was also noted that the SMC addition to the coal tailings did not increase the durability of the pellets due to the limited binding effect between the two materials.
Vida N. Sharifi - One of the best experts on this subject based on the ideXlab platform.
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fuel pelletization with a binder part i identification of a suitable binder for Spent Mushroom Compost coal tailing pellets
Energy & Fuels, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, Jim SwithenbankAbstract:Spent Mushroom Compost and coal tailings are wastes that could be used as energy sources, through combustion in a fluidized-bed. Our previous pelletization studies produced a denser, yet friable fuel, which produced dust on transport, handling, and feeding. Thus, a suitable binder for these materials was required to enhance pellet properties. Inorganic (caustic soda) and organic (starch) binders were selected for a range of tests. Pelletization at elevated temperatures was also assessed to evaluate the softening of any lignin present in the straw component of the Mushroom Compost. Small amounts (up to 1 wt %) of both binders increased pellet tensile strength, where starch had more pronounced impacts, doubling the tensile strength to 411 kPa. Pelletization at elevated temperatures (45−75 °C), however, improved overall pellet quality more significantly, increasing the tensile strength to over 600 kPa, although additional temperature increases (up to 125 °C) did not result in further improvements. Whether a ...
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fuel pelletization with a binder part ii the impacts of binders on the combustion of Spent Mushroom Compost coal tailing pellets
Energy & Fuels, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, J SwithenbankAbstract:Various additives, namely, starch and caustic soda, have been identified in the previous paper as binders to improve the quality of fuel pellets made from two wastes—Spent Mushroom Compost and coal tailings. Combustion tests using these pellets in a small, laboratory-scale fluidized-bed were performed to evaluate the impacts these binders had on the efficiency, emissions, and ash properties. Thermal treatment revealed that combustion of these pellets with either binder was fairly comparable to the control case, where no binder was used, in terms of the temperatures achieved and gaseous emission concentrations (including acid gas species). The combustion efficiencies were lower (88.7% compared to 95.0%), possibly due to a modification in particle structure, however there was less combustible material remaining in the flyash. The use of caustic soda increased the likelihood of slagging/fouling within the system, due to the greater concentration of alkali metal oxides in the flyash. The ash fusion temperatur...
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combustion of Spent Mushroom Compost and coal tailing pellets in a fluidised bed
Renewable Energy, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, Jim SwithenbankAbstract:Abstract Previous investigations found that fluidised-bed combustion of Spent Mushroom Compost–coal tailing pellets was preferred for these high ash content fuels. This paper considers the combustion tests carried out on these wastes in a laboratory-scale fluidised-bed, where parameters, including the pellet feedrate, primary/fluidising air flowrate and bed depth, were investigated. Based on the minimum air ratio of 2.5 required to achieve high combustion efficiencies of around 97%, the optimum operating conditions for the combustor employed were a pellet feedrate of 3.25 kg/h (180 kg/m2h) and a total air flowrate of 650 kg/m2h. A lower sand bed depth of 0.22 m was also deemed beneficial, as deeper beds resulted in slugging and noticeable reductions in combustion efficiency. Acid gas emissions (NOx, SOx and HCl) were found in limited concentrations, as species remained primarily as inorganic compounds in the flyash. Some N2O is thought to have formed, as fluidised-bed combustors are particularly prone to this. The alkali index of the ash suggests probable fouling/slagging in the system. For industrial-scale combustion of these wastes, the combustion efficiency could be improved by the presence of secondary air jets to aid turbulent mixing.
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the reuse of Spent Mushroom Compost and coal tailings for energy recovery comparison of thermal treatment technologies
Bioresource Technology, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, Changkook Ryu, Jim SwithenbankAbstract:Thermal treatment technologies were compared to determine an appropriate method of recovering energy from two wastes - Spent Mushroom Compost and coal tailings. The raw Compost and pellets of these wastes were combusted in a fluidised-bed and a packed-bed, and contrasted to pyrolysis and gasification. Quantitative combustion parameters were compared to assess the differences in efficiency between the technologies. Fluidised-bed combustion was more efficient than the packed-bed in both instances and pellet combustion was superior to that of the Compost alone. Acid gas emissions (NO(x), SO(x) and HCl) were minimal for the fluidised-bed, thus little gas cleaning would be required. The fuels' high ash content (34%) also suggests fluidised-bed combustion would be preferred. The Alkali Index of the ash indicates the possibility of fouling/slagging within the system, caused by the presence of alkali metal oxides. Pyrolysis produced a range of low-calorific value-products, while gasification was not successful.
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pelletised fuel production from coal tailings and Spent Mushroom Compost part ii economic feasibility based on cost analysis
Fuel Processing Technology, 2008Co-Authors: Changkook Ryu, Vida N. Sharifi, Adela Khor, J SwithenbankAbstract:Due to the growing market for sustainable energy, in order to increase the quality of the fuels, pellets are being produced from various materials such as wood and other biomass energy crops, and municipal waste. This paper presents the results from an economic feasibility study for pellet production using blends of two residue materials: coal tailings from coal cleaning and Spent Mushroom Compost (SMC) from Mushroom production. Key variables such as the mixture composition, raw material haulage and plant scale were considered and the production costs were compared to coal and biomass energy prices. For both wet materials, the moisture content was the critical parameter that influenced the fuel energy costs. The haulage distance of the raw materials was another factor that can pose a high risk. The results showed that the pellet production from the above two materials can be viable when a less energy-intensive drying process is utilised. Potential market outlets and ways to lower the costs are also discussed in this paper.
Jim Swithenbank - One of the best experts on this subject based on the ideXlab platform.
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fuel pelletization with a binder part i identification of a suitable binder for Spent Mushroom Compost coal tailing pellets
Energy & Fuels, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, Jim SwithenbankAbstract:Spent Mushroom Compost and coal tailings are wastes that could be used as energy sources, through combustion in a fluidized-bed. Our previous pelletization studies produced a denser, yet friable fuel, which produced dust on transport, handling, and feeding. Thus, a suitable binder for these materials was required to enhance pellet properties. Inorganic (caustic soda) and organic (starch) binders were selected for a range of tests. Pelletization at elevated temperatures was also assessed to evaluate the softening of any lignin present in the straw component of the Mushroom Compost. Small amounts (up to 1 wt %) of both binders increased pellet tensile strength, where starch had more pronounced impacts, doubling the tensile strength to 411 kPa. Pelletization at elevated temperatures (45−75 °C), however, improved overall pellet quality more significantly, increasing the tensile strength to over 600 kPa, although additional temperature increases (up to 125 °C) did not result in further improvements. Whether a ...
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combustion of Spent Mushroom Compost and coal tailing pellets in a fluidised bed
Renewable Energy, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, Jim SwithenbankAbstract:Abstract Previous investigations found that fluidised-bed combustion of Spent Mushroom Compost–coal tailing pellets was preferred for these high ash content fuels. This paper considers the combustion tests carried out on these wastes in a laboratory-scale fluidised-bed, where parameters, including the pellet feedrate, primary/fluidising air flowrate and bed depth, were investigated. Based on the minimum air ratio of 2.5 required to achieve high combustion efficiencies of around 97%, the optimum operating conditions for the combustor employed were a pellet feedrate of 3.25 kg/h (180 kg/m2h) and a total air flowrate of 650 kg/m2h. A lower sand bed depth of 0.22 m was also deemed beneficial, as deeper beds resulted in slugging and noticeable reductions in combustion efficiency. Acid gas emissions (NOx, SOx and HCl) were found in limited concentrations, as species remained primarily as inorganic compounds in the flyash. Some N2O is thought to have formed, as fluidised-bed combustors are particularly prone to this. The alkali index of the ash suggests probable fouling/slagging in the system. For industrial-scale combustion of these wastes, the combustion efficiency could be improved by the presence of secondary air jets to aid turbulent mixing.
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the reuse of Spent Mushroom Compost and coal tailings for energy recovery comparison of thermal treatment technologies
Bioresource Technology, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, Changkook Ryu, Jim SwithenbankAbstract:Thermal treatment technologies were compared to determine an appropriate method of recovering energy from two wastes - Spent Mushroom Compost and coal tailings. The raw Compost and pellets of these wastes were combusted in a fluidised-bed and a packed-bed, and contrasted to pyrolysis and gasification. Quantitative combustion parameters were compared to assess the differences in efficiency between the technologies. Fluidised-bed combustion was more efficient than the packed-bed in both instances and pellet combustion was superior to that of the Compost alone. Acid gas emissions (NO(x), SO(x) and HCl) were minimal for the fluidised-bed, thus little gas cleaning would be required. The fuels' high ash content (34%) also suggests fluidised-bed combustion would be preferred. The Alkali Index of the ash indicates the possibility of fouling/slagging within the system, caused by the presence of alkali metal oxides. Pyrolysis produced a range of low-calorific value-products, while gasification was not successful.
J Swithenbank - One of the best experts on this subject based on the ideXlab platform.
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fuel pelletization with a binder part ii the impacts of binders on the combustion of Spent Mushroom Compost coal tailing pellets
Energy & Fuels, 2009Co-Authors: Karen N. Finney, Vida N. Sharifi, J SwithenbankAbstract:Various additives, namely, starch and caustic soda, have been identified in the previous paper as binders to improve the quality of fuel pellets made from two wastes—Spent Mushroom Compost and coal tailings. Combustion tests using these pellets in a small, laboratory-scale fluidized-bed were performed to evaluate the impacts these binders had on the efficiency, emissions, and ash properties. Thermal treatment revealed that combustion of these pellets with either binder was fairly comparable to the control case, where no binder was used, in terms of the temperatures achieved and gaseous emission concentrations (including acid gas species). The combustion efficiencies were lower (88.7% compared to 95.0%), possibly due to a modification in particle structure, however there was less combustible material remaining in the flyash. The use of caustic soda increased the likelihood of slagging/fouling within the system, due to the greater concentration of alkali metal oxides in the flyash. The ash fusion temperatur...
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pelletised fuel production from coal tailings and Spent Mushroom Compost part ii economic feasibility based on cost analysis
Fuel Processing Technology, 2008Co-Authors: Changkook Ryu, Vida N. Sharifi, Adela Khor, J SwithenbankAbstract:Due to the growing market for sustainable energy, in order to increase the quality of the fuels, pellets are being produced from various materials such as wood and other biomass energy crops, and municipal waste. This paper presents the results from an economic feasibility study for pellet production using blends of two residue materials: coal tailings from coal cleaning and Spent Mushroom Compost (SMC) from Mushroom production. Key variables such as the mixture composition, raw material haulage and plant scale were considered and the production costs were compared to coal and biomass energy prices. For both wet materials, the moisture content was the critical parameter that influenced the fuel energy costs. The haulage distance of the raw materials was another factor that can pose a high risk. The results showed that the pellet production from the above two materials can be viable when a less energy-intensive drying process is utilised. Potential market outlets and ways to lower the costs are also discussed in this paper.
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pelletised fuel production from coal tailings and Spent Mushroom Compost part i identification of pelletisation parameters
Fuel Processing Technology, 2008Co-Authors: Changkook Ryu, Karen N. Finney, Vida N. Sharifi, J SwithenbankAbstract:Abstract This study investigates the technology of manufacturing pellet blends for energy production from two discarded materials in industry. Coal tailings material is the fine discard produced as a result of coal cleaning. Although it still has a significantly high calorific value, over a million tonnes of coal tailings are deposited in lagoons every year in the UK alone. Spent Mushroom Compost (SMC) consists of fibrous Compost substrate and a wet casing layer used during Mushroom production. In the form of pellets, these materials become more homogeneous, easily stored and transported, and suitable for use in power plants or gasifiers. The characterisation of the fuel properties shows that the two materials have a complimentary status for pelletisation and energy production in terms of particle types, carbon source, calorific value and volatile matter content. Pelletisation tests were carried out using a small compression rig for various pressures, moisture contents and mixture compositions. The quality of the pellets was assessed using density, swelling, tensile strength and durability. It was necessary to keep the moisture contents for coal tailings at about 10% and for SMC at 20% before pelletisation in order to maximise the bonding strength of the originally wet materials. Pressures above 6000 psi did not produce noticeably denser or stronger pellets. The pellets from coal tailings and SMC blends had a tensile strength proportional to the SMC fraction. The SMC pellets were more durable than the coal tailing pellets due to the intertwined Compost fibres. It was also noted that the SMC addition to the coal tailings did not increase the durability of the pellets due to the limited binding effect between the two materials.
Ronan Courtney - One of the best experts on this subject based on the ideXlab platform.
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physico chemical changes in bauxite residue following application of Spent Mushroom Compost and gypsum
Land Degradation & Development, 2009Co-Authors: Ronan Courtney, Siobhan N Jordan, Thomas J HarringtonAbstract:Physical properties exhibited by unvegetated mine wastes pose limitations to vegetation establishment and growth. In an attempt to promote vegetation cover on bauxite residue, a field trial was established to determine the effect of Spent Mushroom Compost (SMC) and gypsum amendment on enhancing the physical properties of the residue. SMC was incorporated at rates of 0, 60, 80 and 120 t ha−1 with gypsum at 0, 40 and 90 t ha−1 and Holcus lanatus sown at a rate of 80 kg ha−1. The addition of SMC and gypsum was beneficial in improving the physical properties of the residue and promoting growth. Principally increasing organic content of the residue decreased bulk density and particle density whilst improving substrate porosity. Residue pH, EC and sodicity of the residue were also affected by the amendments, which positively impacted on microaggregate stability and preventing clay dispersion. Pearson correlations demonstrate that the most significant parameters in determining clay dispersion potential are the pH and the exchangeable sodium percentage (ESP) of the residue. Copyright © 2009 John Wiley & Sons, Ltd.
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metal uptake in lolium perenne established on Spent Mushroom Compost amended lead zinc tailings
Land Degradation & Development, 2009Co-Authors: Siobhan N Jordan, George J Mullen, Ronan CourtneyAbstract:A greenhouse trial was performed to contrast the growth and metal accumulation in Lolium perenne established on pyritic tailings amended with varying applications of Spent Mushroom Compost (SMC). The lead-zinc tailings were retrieved from a moderately vegetated land impoundment facility located at Gortmore, Silvermines, Co. Tipperary and SMC was incorporated at application rates of 0, 50, 100, 200 and 400 t ha-1. The grass species Lolium perenne was sown at an application rate of 200 kg ha-1 and the subsequent biomass determined after 42 days and 84 days. For the most part, metal concentrations in Lolium perenne showed a significant linear response (P<0.05) to SMC application and generally decreased favorably with increasing SMC application (P<0.05). This phenomenon may be attributed to the vast biosorption capacity of SMC owing to the presence of phenolic, carboxyl and phenolic functional groups, the development of stable metal chelates by the organic matter present in SMC and/or by the biosorbing of toxic metals by fungal mycelium, however this reduction in metal uptake by Lolium perenne is most likely due to greater plant dry weight caused by the increasing SMC applications. In spite of this, Lolium perenne suffered severe toxicity resulting from the inherently high concentrations of total zinc (1443 to 5920 mg kg-1), lead (33 to 478 mg kg-1) and cadmium (1.4 to 49 mg kg-1) accumulated within the plant 84 days after seeding, the grass had adversely withered irrespective of SMC application. Therefore, a barrier break must be introduced in the tailings facility to prevent the uptake and accumulation of these lethal metal concentrations by plants. Only then should SMC and other suitable soil forming materials be utilized as growing media, as the incorporation of an organic amendment followed by direct seeding of a grass species is not economically or environmentally viable for permanent revegetation of the Gortmore TMF.
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a greenhouse trial on the effects of Spent Mushroom Compost on the microaggregate fraction of lead zinc tailings
Dynamic Soil Dynamic Plant, 2009Co-Authors: Siobhan N Jordan, George J Mullen, Ronan CourtneyAbstract:Particle size analysis was carried out on the microaggregate fraction (<53 µm) of Spent Mushroom Compost (SMC) amended pyritic lead-zinc tailings using laser diffraction. A randomized factorial greenhouse trial of six-month duration was established using tailings originating from the surface (20 to 30 cm) of the partially vegetated 76-ha tailings management facility (TMF) in Gortmore, Silvermines, Co. Tipperary, Ireland. SMC was incorporated at application rates of 0, 50, 100, 200 and 400 t ha-1 and Lolium perenne sown at a rate of 200 kg ha-1. Following trial dismantlement, the effects of SMC treatment on the microaggregate fraction of the tailings was investigated using optical laser diffraction on a Malvern Mastersizer 2000®. At SMC applications of 200 t ha-1 and 400 t ha-1 an increase in clay dispersion was observed as represented by low d(0.10) values, while a reduction in clay dispersion was noted at SMC applications of 50 t ha-1 and 100 t ha-1. Furthermore, microaggregate stability generally decreased with increasing SMC application as noted by a decrease in d(4,3) values. This is probably explained by the change in surface charge following SMC amendment, the low clay concentration and the mineralogy of the lead zinc-tailings, all of which did not prove favorable in the stabilization of the microaggregates present in pyritic lead-zinc tailings. Laser diffraction gave rapid, reliable and consistent results and for the most part showed a shift in particle size distribution between each SMC treatment.
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utilization of Spent Mushroom Compost for the revegetation of lead zinc tailings effects on physico chemical properties of tailings and growth of lolium perenne
Bioresource Technology, 2008Co-Authors: Siobhan N Jordan, George J Mullen, Ronan CourtneyAbstract:In an attempt to promote sustainable vegetation cover on metalliferous tailings, a randomized factorial greenhouse trial of six-month duration was established to determine the effect of Spent Mushroom Compost (SMC) amendment on the physical and chemical properties of the predominantly lead/zinc tailings. The tailings originated from the surface (20-30cm) of the partially-vegetated 76ha tailings management facility (TMF), where more than nine million tonnes of pyritic metalliferous material were deposited in an unlined land impoundment. SMC was incorporated at application rates of 0, 50, 100, 200 and 400tonha(-1), with each treatment replicated 10 times and Lolium perenne sown at a rate of 200kgha(-1). The addition of SMC was beneficent as a growing medium through improvement of the structural status of the tailings and ultimately through the provision of plant nutrients and reduction in metal concentrations. However, this improvement in the structural and chemical status of the tailings is not adequate in maintaining a sustainable vegetation cover and therefore other remedial options such as introducing a capillary break on the surface of the tailings facility are necessary.