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Effect of Hydrothermal Explosion Pretreatment on the Composition and Structure of Calliandra Calothyrsus Shrub – a Lignocellulosic Biomass
Shivanand Yallappa Adaganti,
Basavaraj Mahipat Kulkarni,
Gururaj Pandurang Desai,
Shivappa Shanmukhappa
Issue:
Volume 3, Issue 1, January 2014
Pages:
1-5
Received:
23 October 2013
Published:
20 December 2013
Abstract: Biomass has been pretreated by hydrothermal explosion using different experimental conditions of temperature between 135 and 173°C and operating time of 45 minutes. The effects of hydrothermal explosion conditions have been investigated by measuring chemical compositions (cellulose, hemicelluloses and lignin) in Calliandra calothyrsus. Hydrothermal explosion pretreatment removes the major part of the hemicelluloses, and makes the high cellulose in the solid material for further enzyme hydrolysis. At severity factor of (log Ro) 3.82 (173oC, 7.5 bar, 45 min), the biomass fibers contained the significant lowest hemicelluloses and the highest of celluloses at 4.82 % DW and 58.26 % DW, respectively. Since Calliandra calothyrsus has higher lignin content, lignin structure might be resisting hemicelluloses degradation by hydrothermal explosion pretreatment. Therefore, hydrothermal explosion of lignocellulosic materials to remove hemicelluloses might significantly enhance the efficiency of cellulose hydrolysis.
Abstract: Biomass has been pretreated by hydrothermal explosion using different experimental conditions of temperature between 135 and 173°C and operating time of 45 minutes. The effects of hydrothermal explosion conditions have been investigated by measuring chemical compositions (cellulose, hemicelluloses and lignin) in Calliandra calothyrsus. Hydrothermal...
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A Review on Numerical and Experimental Results of Hydrogen Addition to Natural Gas in Internal Combustion Engines
Javad Zareei,
Faizal Wan Mahmood,
Shahrir Abdullah,
Yusoff Ali
Issue:
Volume 3, Issue 1, January 2014
Pages:
6-12
Received:
16 November 2013
Published:
10 January 2014
Abstract: Conventional fossil fuel for combustion system, such as gasoline and petroleum have long been recognized as powerful energy source, however these have a number of problems related to emissions and energy security. The use of hydrogen blends with natural gas is a viable alternative to pure fossil fuels because of the expected reduction of the total pollutant emissions and increase of efficiency. Enhancement of chemical reaction with hydrogen addition is regarded as the increase of H, O and OH free radical mole fraction in the flame. Also in SI engines will move the lean limit to leaner mixture, increasing the combustion speed and temperature. Results show that the hydrogen has a catalyzing effect in the ignition of hydrocarbons with only a few percent addition of hydrogen by volume and by adding it to the pure natural gas (CNG) this difference in spark advance of the engine may be reduced, as a result of the higher flame speed of hydrogen. In this paper, we present the advances and development made on internal combustion engines which operate with mixture of hydrogen/CNG, doing more emphasis in the combustion process, ignition energy and injection systems. Also this paper mentions a comparison that experimental and numerical results match quite well expect for extremely fuel lean condition. The nozzle geometry has an important influence on injection process and combustion development and shows that degree of conicity can be evaluated for each nozzle by the K- Factor.
Abstract: Conventional fossil fuel for combustion system, such as gasoline and petroleum have long been recognized as powerful energy source, however these have a number of problems related to emissions and energy security. The use of hydrogen blends with natural gas is a viable alternative to pure fossil fuels because of the expected reduction of the total ...
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Physiochemical and Phase Behaviour Study of Jatropha curcus Oil - Ethanol Microemulsion Fuels Using Sorbitane Fatty Esters
Vivek Patidar,
Abhishek Chandra,
Man Singh,
Raosaheb Kathalupant Kale
Issue:
Volume 3, Issue 1, January 2014
Pages:
13-19
Received:
13 December 2013
Published:
30 January 2014
Abstract: Vegetable oil reverse micelle microemulsions have been an alternative method of biodiesel production to eliminate and avoid transesterification as well as unpurified glycerol. Sorbitane fatty ester surfactants due to their high solubilization capacity forms microemulsions with oils and thus span based reverse micelle microemulsion systems have been studied. Jatropha oil-ethanol microemulsions have been prepared using span 80 and 85 surfactants and optimized as biofuel, their phase behavior with physicochemical parameters: density, viscosity and surface tension were analyzed for formulation. The surface tension has been an important physicochemical parameter in addition to kinematic viscosity elucidating Jatropha oil-ethanol microemulsion with span 80 than with span 85, as a better biofuel. Comparatively, a lower amount of span 80 than span 85 was utilized for microemulsion formulations and resulted viscosities were in close agreement with ASTM biodiesel standards. The microemulsification approach has been found a sustainable method for producing biofuels without chemical reactions and their fuel properties have been adjusted through variable formulations.
Abstract: Vegetable oil reverse micelle microemulsions have been an alternative method of biodiesel production to eliminate and avoid transesterification as well as unpurified glycerol. Sorbitane fatty ester surfactants due to their high solubilization capacity forms microemulsions with oils and thus span based reverse micelle microemulsion systems have been...
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Design and Fabrication and Testing of a Low Speed Wind Turbine Generator Using Tapered Type Rotor Blade Made from Fibre Reinforced Plastic
Saoke Churchill Otieno,
Kamau Joseph Ngugi,
Nishizawa Yoshifumi,
Kinyua Robert,
Ushiyama Izumi,
Nakajo Yuishi
Issue:
Volume 3, Issue 1, January 2014
Pages:
20-25
Received:
19 January 2014
Published:
20 February 2014
Abstract: This study fabricated a three bladed wind turbine of 0.6 m rotor diameter. The blade was divided into ten sections and shape derived from the blade element and momentum theory with two linearization points at 70% and 90%.. Other design values chosen were; clark Y as the airfoil type, 2.5 as tip speed ratio, 1.1 as lift drag ratio, design angle of attack of 8o. The rotor blades were fabricated using two layers of fibre reinforced plastic and 2% hardenning on resin. The power coefficient of the turbine was tested in the wind tunnel by subjecting it to wind speeds ranging from 4 m/s to 10 m/s in the wind tunnel testing. The wind tunnel used for the study was the Effel type with an exit of 1.05 mX1.05 m and wind speed adjustable between 2 m/s to 22.5 m/s. An induction motor was used to provide the load in the experiment and the synchronized frequency controlled by an inverter. A direct connection generator was employed to the turbine rotors to determine the electricity generation capacity. The maximum coefficient of power for the blade was found to be 0.26 at 10 m/s and 651 rpm. A variable resistance was used to determine the electric power production at different rotational speed. A speed of 10 m/s gave the highest power of 29.69 W at 891 rpm, 8 m/s gave the highest power as 15.43 W at 688 rpm, 6 m/s gave the highest power as 6.38 W at 552 rpm while 4 m/s gave the highest power as 1.74 W at 302 rpm. The Wind generator was then used to charge a 54 AH, 12 V battery producing the highest electrical power of 32.03 W. The turbine is capapble of producing power for small wind regimes with small household usage however it is recommended that the design should be optimized to improve the coefficient of power.
Abstract: This study fabricated a three bladed wind turbine of 0.6 m rotor diameter. The blade was divided into ten sections and shape derived from the blade element and momentum theory with two linearization points at 70% and 90%.. Other design values chosen were; clark Y as the airfoil type, 2.5 as tip speed ratio, 1.1 as lift drag ratio, design angle of a...
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Pretreatments to Enhance the Digestibility of Wheat Straw
Issue:
Volume 3, Issue 1, January 2014
Pages:
26-34
Received:
20 January 2014
Published:
20 February 2014
Abstract: Wheat straw is a sufficient agricultural by-product with a low market price. The biofuel produced from lignocellulosic material exhibits energetic, economic and environmental benefits in contrast to bio-ethanol from starch or sugar. Until now, physical and chemical difficulty caused by the close connection of the main components of lignocellulosic biomass, discourage the hydrolysis of cellulose and hemicellulose to fermentable sugars. The main purpose of pretreatment is to enhance the enzyme accessibility improving digestibility of cellulose. Every pretreatment has a particular effect on the fraction of cellulose, hemicellulose and lignin, thus different pretreatment methods and conditions should be selected for the development of subsequent hydrolysis and fermentation steps. This paper reviews the most importance technologies for ethanol production from lignocellulose and its represent several vital qualities that should be marked for low-price and promote pretreatment processes.
Abstract: Wheat straw is a sufficient agricultural by-product with a low market price. The biofuel produced from lignocellulosic material exhibits energetic, economic and environmental benefits in contrast to bio-ethanol from starch or sugar. Until now, physical and chemical difficulty caused by the close connection of the main components of lignocellulosic ...
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