The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Alvin R. Womac - One of the best experts on this subject based on the ideXlab platform.
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Modeling and Characterization of Biomass Size Reduction
2007 Minneapolis Minnesota June 17-20 2007, 2007Co-Authors: Ladan J. Naimi, Shahab Sokhansanj, C. Jim Lim, Alvin R. Womac, Sudhagar ManiAbstract:Forestry and agricultural biomass are modern energy feedstock to produce process heat, power and liquid fuels. Preparation and pre-processing of biomass involve a number of operations including drying, Size Reduction, and fractionation. Among them, Size Reduction is one of the important operations, which consumes relatively high amount of energy. Depending on the type of biomass conversion technologies (such as combustion, gasification, fermentation and densification), special particle Size ranges of materials is needed. In this paper, the mathematical modeling of particle Size distribution of biomass (a fibrous material) during grinding is conducted based on the population balance method. The changes in the Size distribution during the primary breakage of a narrow Size are studied. The model developed to predict particle Size distribution during grinding is validated with experimental data.
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Biomass Pre-Processing Size Reduction with Instrumented Mills
2007 Minneapolis Minnesota June 17-20 2007, 2007Co-Authors: Alvin R. Womac, Shahab Sokhansanj, C. Igathinathane, Prasad Bitra, Petre I. Miu, T Yang, S. NarayanAbstract:Rotary Size Reduction equipment were instrumented to identify important operating parameters with the aim of minimizing energy consumption while reducing the Size of lignocellulosic biomass. Size Reduction equipment included a knife mill, hammer mill, and disc mill. Monitored parameters included input power and particle Size distributions.. Operating parameters included angular velocity, mass rate, screen Size, and biomass selection. Results indicated optimum operating conditions with minimal energy input. Geometric mean dimensions of biomass particles varied from 5x for particle length to 0.3x for particle width when comparing actual to ASABE sieve results – highlighting the need for better consensus standards on particle Size reporting.
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Size Reduction of Wet and Dry Biomass by Linear Knife Grid Device
2007 Minneapolis Minnesota June 17-20 2007, 2007Co-Authors: Igathinathane Cannayen, Shahab Sokhansanj, Alvin R. Womac, S. NarayanAbstract:Linear action of forcing biomass materials through a grid of interlocking knives is an alternative method of Size Reduction, contrast to rotary action involved in existing Size Reduction machines. A laboratory-scale linear action knife grid device prototype developed earlier was used to determine the Size Reduction characteristics of selected biomass, namely, corn stalks and switchgrass at several material and operating conditions. This study was aimed at determining and comparing the ultimate cutting stresses and cutting energy variation between corn stalks and switchgrass, moisture conditions (high- and low-moisture), knife grid spacing (25.4, 50.8, and 101.6 mm), and packed bed depth (50.8, 101.6, and 152.4 mm). The device is composed of ram – attached to crosshead of universal testing machine (UTM), feed block – holds feed, knife grid –arranged at variable grid spacing, knife holder block – holds knife grid, and product block – collects product, and the whole assembly is tested in UTM fitted with 222.41 kN (5000 lb) load cell. New surface area generated during Size Reduction was evaluated based on circle packing theory. Ultimate cutting stresses were evaluated as the ratio of peak load to the cutting plane area (MPa) represented by the knife grid. Cutting energies were evaluated from the area under load-displacement curves and expressed in moisture free basis mass-based energy (MJ/dry Mg) and new surface area-based energy (kJ/m2). Overall results indicated that ultimate cutting stress and cutting energy of corn stalks were significantly (P
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Cost and Performance of Woody Biomass Size Reduction for Energy Production
2006 CSBE SCGAB Edmonton AB Canada July 16-19 2006, 2006Co-Authors: Ladan J. Naimi, Shahab Sokhansanj, Alvin R. Womac, Sudhagar Mani, Mozammel Hoque, Tn Usa, S. NarayanAbstract:Size Reduction is often a first step in primary processing of biomass for its handling and downstream processing applications. Selecting appropriate equipment for Size Reduction has a very important role in the biomass preparation. One of the main reasons is that Size Reduction equipment consumes large quantities of power. In this paper, we reviewed commercial equipment used for Size Reduction of woody biomass. The review also included the capital cost, operating costs and performance of equipment. The performance of equipment is evaluated based on its power consumption and the quality of chip production, which includes average particle Size and particle Size distribution. The type of equipment used depends upon the end use of biomass. For pulping applications, woody biomass is chipped to a uniform Size of 2.5cm x 5cm (1in x 2in) with a thickness of 6mm (1/4in). For energy production, the Size of biomass depends upon the type of burners used and it ranges from 6mm (¼in) to 5cm (2in). To distinguish between wood chips for pulping and ground material for energy production the word "hog fuels" is used. The
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Review of Biomass Size Reduction Technology
2003 Las Vegas NV July 27-30 2003, 2003Co-Authors: Alvin R. Womac, Lester O PordesimoAbstract:Biomass Size Reduction is an important step in biomass densification and this article reviews Reduction studies. Hammermilling technology had the advantage of low maintenance over other methods including crushing, shearing and rollermilling. A review of equipment design parameters showed that hammermill tip speed, power requirements, grinding rate, screen Size, and clearance affect performance to varying degrees. The effects of biomass tensile and shear properties, moisture content, and biomass density were noted in Size Reduction processes.
S. Narayan - One of the best experts on this subject based on the ideXlab platform.
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Biomass Pre-Processing Size Reduction with Instrumented Mills
2007 Minneapolis Minnesota June 17-20 2007, 2007Co-Authors: Alvin R. Womac, Shahab Sokhansanj, C. Igathinathane, Prasad Bitra, Petre I. Miu, T Yang, S. NarayanAbstract:Rotary Size Reduction equipment were instrumented to identify important operating parameters with the aim of minimizing energy consumption while reducing the Size of lignocellulosic biomass. Size Reduction equipment included a knife mill, hammer mill, and disc mill. Monitored parameters included input power and particle Size distributions.. Operating parameters included angular velocity, mass rate, screen Size, and biomass selection. Results indicated optimum operating conditions with minimal energy input. Geometric mean dimensions of biomass particles varied from 5x for particle length to 0.3x for particle width when comparing actual to ASABE sieve results – highlighting the need for better consensus standards on particle Size reporting.
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Size Reduction of Wet and Dry Biomass by Linear Knife Grid Device
2007 Minneapolis Minnesota June 17-20 2007, 2007Co-Authors: Igathinathane Cannayen, Shahab Sokhansanj, Alvin R. Womac, S. NarayanAbstract:Linear action of forcing biomass materials through a grid of interlocking knives is an alternative method of Size Reduction, contrast to rotary action involved in existing Size Reduction machines. A laboratory-scale linear action knife grid device prototype developed earlier was used to determine the Size Reduction characteristics of selected biomass, namely, corn stalks and switchgrass at several material and operating conditions. This study was aimed at determining and comparing the ultimate cutting stresses and cutting energy variation between corn stalks and switchgrass, moisture conditions (high- and low-moisture), knife grid spacing (25.4, 50.8, and 101.6 mm), and packed bed depth (50.8, 101.6, and 152.4 mm). The device is composed of ram – attached to crosshead of universal testing machine (UTM), feed block – holds feed, knife grid –arranged at variable grid spacing, knife holder block – holds knife grid, and product block – collects product, and the whole assembly is tested in UTM fitted with 222.41 kN (5000 lb) load cell. New surface area generated during Size Reduction was evaluated based on circle packing theory. Ultimate cutting stresses were evaluated as the ratio of peak load to the cutting plane area (MPa) represented by the knife grid. Cutting energies were evaluated from the area under load-displacement curves and expressed in moisture free basis mass-based energy (MJ/dry Mg) and new surface area-based energy (kJ/m2). Overall results indicated that ultimate cutting stress and cutting energy of corn stalks were significantly (P
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Cost and Performance of Woody Biomass Size Reduction for Energy Production
2006 CSBE SCGAB Edmonton AB Canada July 16-19 2006, 2006Co-Authors: Ladan J. Naimi, Shahab Sokhansanj, Alvin R. Womac, Sudhagar Mani, Mozammel Hoque, Tn Usa, S. NarayanAbstract:Size Reduction is often a first step in primary processing of biomass for its handling and downstream processing applications. Selecting appropriate equipment for Size Reduction has a very important role in the biomass preparation. One of the main reasons is that Size Reduction equipment consumes large quantities of power. In this paper, we reviewed commercial equipment used for Size Reduction of woody biomass. The review also included the capital cost, operating costs and performance of equipment. The performance of equipment is evaluated based on its power consumption and the quality of chip production, which includes average particle Size and particle Size distribution. The type of equipment used depends upon the end use of biomass. For pulping applications, woody biomass is chipped to a uniform Size of 2.5cm x 5cm (1in x 2in) with a thickness of 6mm (1/4in). For energy production, the Size of biomass depends upon the type of burners used and it ranges from 6mm (¼in) to 5cm (2in). To distinguish between wood chips for pulping and ground material for energy production the word "hog fuels" is used. The
Shahab Sokhansanj - One of the best experts on this subject based on the ideXlab platform.
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Modeling Size Reduction and Fractionation for Cellulosic Feedstock
Innovative Solutions in Fluid-Particle Systems and Renewable Energy Management, 2015Co-Authors: Ladan J. Naimi, Shahab Sokhansanj, C. Jim Lim, Anthony Lau, Mohammad Emami, Staffan MelinAbstract:Biomass has attracted attention as a source of renewable energy. It is available in different forms such as lignocellulosic stalks of herbaceous and woody biomass. These forms of biomass should be prepared to go through bioconversion process or biofuel production. One of the major unit operations for preparation is Size Reduction, which increases the surface area available and breaks the structure of biomass. Size Reduction is energy intensive and an expensive step of feedstock preparation. The characteristics of ground particles are the result of interactions between material properties and the modes of Size Reduction like shear, impact, and attrition. The fundamentals of Size Reduction of fibrous biomass are not well understood. This chapter summarizes the latest studies on modeling of Size Reduction of lignocellulosic and woody biomass.
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Biomass Pre-Processing Size Reduction with Instrumented Mills
2007 Minneapolis Minnesota June 17-20 2007, 2007Co-Authors: Alvin R. Womac, Shahab Sokhansanj, C. Igathinathane, Prasad Bitra, Petre I. Miu, T Yang, S. NarayanAbstract:Rotary Size Reduction equipment were instrumented to identify important operating parameters with the aim of minimizing energy consumption while reducing the Size of lignocellulosic biomass. Size Reduction equipment included a knife mill, hammer mill, and disc mill. Monitored parameters included input power and particle Size distributions.. Operating parameters included angular velocity, mass rate, screen Size, and biomass selection. Results indicated optimum operating conditions with minimal energy input. Geometric mean dimensions of biomass particles varied from 5x for particle length to 0.3x for particle width when comparing actual to ASABE sieve results – highlighting the need for better consensus standards on particle Size reporting.
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Modeling and Characterization of Biomass Size Reduction
2007 Minneapolis Minnesota June 17-20 2007, 2007Co-Authors: Ladan J. Naimi, Shahab Sokhansanj, C. Jim Lim, Alvin R. Womac, Sudhagar ManiAbstract:Forestry and agricultural biomass are modern energy feedstock to produce process heat, power and liquid fuels. Preparation and pre-processing of biomass involve a number of operations including drying, Size Reduction, and fractionation. Among them, Size Reduction is one of the important operations, which consumes relatively high amount of energy. Depending on the type of biomass conversion technologies (such as combustion, gasification, fermentation and densification), special particle Size ranges of materials is needed. In this paper, the mathematical modeling of particle Size distribution of biomass (a fibrous material) during grinding is conducted based on the population balance method. The changes in the Size distribution during the primary breakage of a narrow Size are studied. The model developed to predict particle Size distribution during grinding is validated with experimental data.
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Size Reduction of Wet and Dry Biomass by Linear Knife Grid Device
2007 Minneapolis Minnesota June 17-20 2007, 2007Co-Authors: Igathinathane Cannayen, Shahab Sokhansanj, Alvin R. Womac, S. NarayanAbstract:Linear action of forcing biomass materials through a grid of interlocking knives is an alternative method of Size Reduction, contrast to rotary action involved in existing Size Reduction machines. A laboratory-scale linear action knife grid device prototype developed earlier was used to determine the Size Reduction characteristics of selected biomass, namely, corn stalks and switchgrass at several material and operating conditions. This study was aimed at determining and comparing the ultimate cutting stresses and cutting energy variation between corn stalks and switchgrass, moisture conditions (high- and low-moisture), knife grid spacing (25.4, 50.8, and 101.6 mm), and packed bed depth (50.8, 101.6, and 152.4 mm). The device is composed of ram – attached to crosshead of universal testing machine (UTM), feed block – holds feed, knife grid –arranged at variable grid spacing, knife holder block – holds knife grid, and product block – collects product, and the whole assembly is tested in UTM fitted with 222.41 kN (5000 lb) load cell. New surface area generated during Size Reduction was evaluated based on circle packing theory. Ultimate cutting stresses were evaluated as the ratio of peak load to the cutting plane area (MPa) represented by the knife grid. Cutting energies were evaluated from the area under load-displacement curves and expressed in moisture free basis mass-based energy (MJ/dry Mg) and new surface area-based energy (kJ/m2). Overall results indicated that ultimate cutting stress and cutting energy of corn stalks were significantly (P
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Cost and Performance of Woody Biomass Size Reduction for Energy Production
2006 CSBE SCGAB Edmonton AB Canada July 16-19 2006, 2006Co-Authors: Ladan J. Naimi, Shahab Sokhansanj, Alvin R. Womac, Sudhagar Mani, Mozammel Hoque, Tn Usa, S. NarayanAbstract:Size Reduction is often a first step in primary processing of biomass for its handling and downstream processing applications. Selecting appropriate equipment for Size Reduction has a very important role in the biomass preparation. One of the main reasons is that Size Reduction equipment consumes large quantities of power. In this paper, we reviewed commercial equipment used for Size Reduction of woody biomass. The review also included the capital cost, operating costs and performance of equipment. The performance of equipment is evaluated based on its power consumption and the quality of chip production, which includes average particle Size and particle Size distribution. The type of equipment used depends upon the end use of biomass. For pulping applications, woody biomass is chipped to a uniform Size of 2.5cm x 5cm (1in x 2in) with a thickness of 6mm (1/4in). For energy production, the Size of biomass depends upon the type of burners used and it ranges from 6mm (¼in) to 5cm (2in). To distinguish between wood chips for pulping and ground material for energy production the word "hog fuels" is used. The
Ladan J. Naimi - One of the best experts on this subject based on the ideXlab platform.
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Modeling Size Reduction and Fractionation for Cellulosic Feedstock
Innovative Solutions in Fluid-Particle Systems and Renewable Energy Management, 2015Co-Authors: Ladan J. Naimi, Shahab Sokhansanj, C. Jim Lim, Anthony Lau, Mohammad Emami, Staffan MelinAbstract:Biomass has attracted attention as a source of renewable energy. It is available in different forms such as lignocellulosic stalks of herbaceous and woody biomass. These forms of biomass should be prepared to go through bioconversion process or biofuel production. One of the major unit operations for preparation is Size Reduction, which increases the surface area available and breaks the structure of biomass. Size Reduction is energy intensive and an expensive step of feedstock preparation. The characteristics of ground particles are the result of interactions between material properties and the modes of Size Reduction like shear, impact, and attrition. The fundamentals of Size Reduction of fibrous biomass are not well understood. This chapter summarizes the latest studies on modeling of Size Reduction of lignocellulosic and woody biomass.
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Modeling and Characterization of Biomass Size Reduction
2007 Minneapolis Minnesota June 17-20 2007, 2007Co-Authors: Ladan J. Naimi, Shahab Sokhansanj, C. Jim Lim, Alvin R. Womac, Sudhagar ManiAbstract:Forestry and agricultural biomass are modern energy feedstock to produce process heat, power and liquid fuels. Preparation and pre-processing of biomass involve a number of operations including drying, Size Reduction, and fractionation. Among them, Size Reduction is one of the important operations, which consumes relatively high amount of energy. Depending on the type of biomass conversion technologies (such as combustion, gasification, fermentation and densification), special particle Size ranges of materials is needed. In this paper, the mathematical modeling of particle Size distribution of biomass (a fibrous material) during grinding is conducted based on the population balance method. The changes in the Size distribution during the primary breakage of a narrow Size are studied. The model developed to predict particle Size distribution during grinding is validated with experimental data.
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Cost and Performance of Woody Biomass Size Reduction for Energy Production
2006 CSBE SCGAB Edmonton AB Canada July 16-19 2006, 2006Co-Authors: Ladan J. Naimi, Shahab Sokhansanj, Alvin R. Womac, Sudhagar Mani, Mozammel Hoque, Tn Usa, S. NarayanAbstract:Size Reduction is often a first step in primary processing of biomass for its handling and downstream processing applications. Selecting appropriate equipment for Size Reduction has a very important role in the biomass preparation. One of the main reasons is that Size Reduction equipment consumes large quantities of power. In this paper, we reviewed commercial equipment used for Size Reduction of woody biomass. The review also included the capital cost, operating costs and performance of equipment. The performance of equipment is evaluated based on its power consumption and the quality of chip production, which includes average particle Size and particle Size distribution. The type of equipment used depends upon the end use of biomass. For pulping applications, woody biomass is chipped to a uniform Size of 2.5cm x 5cm (1in x 2in) with a thickness of 6mm (1/4in). For energy production, the Size of biomass depends upon the type of burners used and it ranges from 6mm (¼in) to 5cm (2in). To distinguish between wood chips for pulping and ground material for energy production the word "hog fuels" is used. The
Gabor A Somorjai - One of the best experts on this subject based on the ideXlab platform.
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fabrication of sub 10 nm silicon nanowire arrays by Size Reduction lithography
Journal of Physical Chemistry B, 2003Co-Authors: Yangkyu Choi, Ji Zhu, Jeff Grunes, Jeffrey Bokor, Gabor A SomorjaiAbstract:A photolithography-based method capable of Size Reduction to produce sub-10-nm Si nanowire arrays on a wafer scale is described. By conformally depositing a material (silicon oxide or silicon) that has a different etching property over a lithographically defined sacrificial sidewall and selectively removing the sacrificial material, the sidewall material is preserved and can serve as nanopattern mask for further processing. The resolution of this method is not limited by photolithography but by the thickness of the material deposited. The application of Size Reduction nano-patterning method can range from the fabrication of biosensors to model catalyst systems.
