Evaluation of Environmental Impacts Resulting from Electric Power Generation and Steel Manufacturing using Coal as Fuel Source
IJTEE, volume-13 , Issue 2 (2018), PP 143 - 153
Published: 29 Jan 2018
by Aniekan E. Ikpe, Owunna Ikechukwu, Ememobong Ikpe from Department of Mechanical Engineering, Coventry University, Priory Street, CV15FB, West Midlands UK Department of Instrumentation and Control, Exxon Mobil Producing Nigeria, Eket, Akwa Ibom State, Nigeria
Abstract: Our environment is extremely important to Intergovernmental Panel on Climate Change (1PCC) and other environmental protection agencies because it is a place where flora and fauna as well as the entire human population of the world exist. This report evaluates the environmental impacts resulting from the use of coal as a source of fuel for electricity power generation and coal as a fuel source to generate electricity for steel production process. GABI models were developed for each of the processes and used for the assessment and analysis to ensure compliance with ISO 14044 standards. After identifying the numerous forms of emission obtained from GABI software, the results were compared to determine the environmental impact and severity of each process. The result for Global Warming Potential (GWP) using coal as a fuel source for steel production accounted for 129.7029 Kg of CO2 equivalence compared to 0.447267Kg of CO2 equivalence result obtained as the GWP for using coal as fuel source for electric power generation. Similarly, the result obtained for acidification when coal is used as a fuel source for steel production recorded 0.360921Kg of SO4 equivalence compared to 1.4026Kg of SO4 equivalence obtained as acidification value for using coal as fuel source for electric power generation. Furthermore, the result obtained for Eutrophication when coal is used as a source of fuel for steel production accounted for -1389.273e-4Kg of phosphate equivalence compared to 2.2417Kg of phosphate equivalence obtained as the Eutrophication value for using coal as a source of fuel for electric power generation. From the aforementioned results, Eutrophication potential and Acidification potential would have lower environmental impacts for both processes whereas, the GWP for electric power generation was quite minimal while GWP for steel production using coal as a fuel source would have relatively high impact on the environment. For this reasons, it was concluded that electric power generation using coal as a source of fuel has less environmental impact whereas, steel production using coal as a source of fuel may not be environmentally friendly due to the high GWP obtained in this report. read more... read less...
Keywords: Coal, Life Cycle Analysis, Environmental Impact, Power Generation, Steel Manufacturing
Revamped Cooling of a Rectangular Shaped Chip Inserting a Highly Conductive Solid: Coupled vs. Uncoupled Conceptions
IJTEE, volume-13 , Issue 2 (2018), PP 135 - 141
Published: 28 Jan 2018
by M. R. Hajmohamdami, A. Campob from Department of Mechanical Engineering, Amirkabir University of Technology, Tehran, 158754413, Iran Department of Mechanical Engineering, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
Abstract: The performance of highly conductive inserts embedded into a heated chip has been investigated in recent years. The role of the insert was to gather the heat current within the chip and remove it to a low temperature heat sink. The central goal of this study is to invoke several reconsiderations, which results in the plausible reduction of the peak temperature in a heated rectangular chip in comparison with the lowest peak temperature achieved in previous works. It is proved that for the configuration under study with its bottom surface receiving a constant uniform heat flux, the branching patterns of the insert must be avoided, instead the appropriate revisions in the architecture (width, location and cross section area) of the insert are accounted for the simple patterns. An uncoupled analytical solution for predicting the peak temperatures in the rectangular chip containing the cooling insert is also addressed. It is also proved that under the same volume fraction and thermal conductivity of the insert, the peak temperature can be reduced to 2.9 °C, which is 94% below the lowest temperature reported in the archival literature, which was around 50.5 °C. read more... read less...
Keywords: electronics cooling, rectangular chip, highly conductive insert, minimized peak temperature
IJTEE, volume-13 , Issue 2 (2018), PP 129 - 133
Published: 28 Jan 2018
by E.K. Orhorhoro, O.W. Orhorhoro, A.E. Ikpe from Cemek Machinery Company, Technology Incubation Centre, Federal Ministry of Science & Technology, Nigeria Electrical/Electronic Engineering Department, Delta State Polytechnic Oghara, Nigeria Department of Mechanical Engineering, University of Benin, Benin City, Nigeria
Abstract: In this paper, a study was carried out on solar energy potential in Sapele, Nigeria. Five photovoltaic solar panel (cell) connected in series where used to generate data on maximum and minimum temperature readings, voltage and current readings for a period of 50 days. The result obtained shown that a mean average temperature readings of 30.01 °C, mean average voltage readings of 14.23 V and mean average current reading of 4.206 A were obtained. The global solar radiation and extraterrestrial solar radiation were calculated as 11.09 kwh/m2 /day and 5.31kwh/m2 /day respectively. Considering the average power deposited (0.060 kW and 0.180 kWh) read more... read less...
Keywords: Solar energy potential, temperature, power deposited, global solar radiation, Sapele, Nigeria
Engine Performance and Emission Characteristics of a Direct Injection Diesel Engine Fuelled with 1- Hexanol as a Fuel Additive in Mahua Seed Oil Biodiesel Blends
IJTEE, volume-13 , Issue 2 (2018), PP 121 - 127
Published: 28 Jan 2018
by V. Dhana Raju, K. Kirankumar, P.S. Kishore from Mechanical Engineering Department, LBRCE, Mylavaram, India Mechanical Engineering Department, Amrita sai Institute of Science &Technology, Paritala, India Mechanical Engineering Department, Andhra University, Vizag, India
Abstract: The increasing industrialization and motorization of the world has led to a steep rise for the demand of petroleum products. Petroleum based fuels are obtained from limited reserves. In the wake of this situation, there is an urgent need to promote use of alternative fuel which must be technically feasible, economically competitive, environmentally acceptable and readily available. In the present study, Mahua seed oil methyl esters (MSOME) were prepared through transesterification and evaluation of important physico-chemical properties was carried and the properties were found within acceptable limits. A compression ignition engine was fuelled with three blends of MSOME with diesel (10, 20 and 30% on volume basis) and various performance and emission characteristics were evaluated and results compared with baseline data of diesel. The results suggest the BTE was higher for MSOME blends and BSFC, HC and smoke opacity were lower as compared to diesel fuel. This may be attributed to improved combustion for MSOME are oxygenated fuels and have higher cetane number. The values of NOx were found almost nearer for all blends as compared to diesel. Addition of 1-hexanol (Ignition improver) 0.5%, 1% volume ratios to the optimum blend (MSOME30) for evaluating the engine performance and emissions parameters and the main purpose of ignition improver is to improve combustion process and reduction in engine emissions. Finally results shows that performance and emissions have been to justify the potentiality of the mahua seed oil methyl esters as alternative fuel for compression ignition engines without any modifications. read more... read less...
Keywords: Mahua seed oil, Transesterification, Bio-diesel, Methanol, NOx
IJTEE, volume-13 , Issue 2 (2018), PP 113 - 120
Published: 28 Jan 2018
by B.G. Prashantha, M.S. Govinde Gowda, S. Seetharamu, G.S.V.L. Narasimham from Department of Industrial Engineering & Management, JSS Academy of Technical Education, Dr. Vishnuvardhana Road, Bangalore-560 060, India Department of Mechanical Engineering, Nagarjuna College of Engineering and Technology, Bengaluru-562 164, India Central Power Research Institute, Bangalore-560 080, India Department of Mechanical Engineering, Indian Institute of Science, Bangalore-560 012, India
Abstract: In this paper, thermoacoustic refrigerator design strategy with parameters normalization and literature review covering the recent development in the modification of the resonator shape and size is discussed. The design of a 10 W cooling power thermoacoustic refrigerator using air as working substance and the effect of operating frequency on viscous and thermal penetration depths, and on stack sheet thickness and spacing are discussed. The promising 10 W cooling power TDH (Taper and Divergent section with Hemispherical end) resonator design operating with air and helium gases as working substances is analyzed using DeltaEC software. The analysis results show that the TDH resonator design using helium as working substance operates at lower drive ratio (14%) compared to air (25%). In comparison, DeltaEC predicts a decent low temperature of -35.4 o C at cold heat exchanger with a COP of 0.5294 when operated using helium gas, and for air is -9 oC and 0.8113 respectively, and the results are discussed. read more... read less...
Keywords: Thermoacoustic, TDH design, Drive ratio, DeltaEC
Fabrication and Performance Evaluation of Savonious Vertical Axis Wind Turbine for Uncertain Speed Regions
IJTEE, volume-13 , Issue 2 (2018), PP 107 - 111
Published: 28 Jan 2018
by S. Naga Kishore, T. Venkateswara Rao, M.L.S. Deva Kumar from Department of Mechanical Engineering, RSR Engineering College, Kadanuthala, AP, India Department of Mechanical Engineering, KL University, Vaddeswaram, AP, India Department of Mechanical Engineering, JNTUCEA, Anantapur, AP, India
Abstract: The consumption of electricity in urban as well as rural is increasing every day and became an essential commodity for household and industrial purposes. Unfortunately the availability of electrical energy in India is not sufficient to the required demand and it is essential to discover and generate energy from non-conventional sources with cheap cost. On the same time it is necessary to reduce the consumption of conventional sources and to save fuel. Among all the renewable resources, wind is one of the best resources available all the time at free of cost. Especially vertical axis wind turbines (VAWT) are self-starting, omni directional. They require no yaw mechanism to continuously orient towards the wind direction and provide a more reliable energy conversion technology, as compared to horizontal axis wind turbine. Particularly savonius vertical axis wind turbines (SVAWT) are suitable and practically possible at low or uncertain wind speed regimes. They can be fitted on rooftops and also suitable for the urban areas where electricity is not available properly. This project deals with the fabrication and performance evaluation of savonius vertical axis wind turbine using two blade rotor. The amount of power developed by the wind turbine is calculated under theoretical and practical conditions and aerodynamics coefficients are also estimated. And various design parameters of savonious rotor are identified and determined. read more... read less...
Keywords: Savonious, Vertical Axis Wind turbine, Velocity, Power, Rotor.
IJTEE, volume-13 , Issue 2 (2018), PP 101 - 105
Published: 28 Jan 2018
by M. Mujahid Rafique from Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia
Abstract: The liquid desiccant cooling system is found to be a good alternative of conventional air conditioning system for better control of both latent and sensible loads. The major component of a liquid desiccant cooling system is desiccant dehumidifier which controls the latent cooling load. In this paper a mathematical model for rotary type liquid desiccant dehumidifier commonly known as desiccant wheel has been presented. The desiccant wheel has a cylindrical shape with a number of identical narrow circular slots distributed uniformly over the rotor cross section. The slots are filled with a porous medium carrying the solution of liquid desiccant, to make the absorbing surface. The absorption and regeneration performance of the desiccant dehumidifier is discussed in this paper for different operating conditions. The wheel performance curves which help to determine the air outlet conditions and coefficient of performance (COP) of the system are drawn for a wide range of wheel thickness (0.06-0.6m), air mass flux (1-8 kg/m2 .s), and regeneration temperature (60- 85o C). A reduction of about 30% in outlet humidity ratio is observed with an increase in the wheel thickness from 0.06 to 0.2m. The computed results show that better supply air conditions can be obtained to provide human thermal comfort in the hot and humid climate with effectiveness of the system largely dependent on air flow rate, wheel thickness and humidity ratio of process air. read more... read less...
Keywords: Liquid desiccant wheel, heat and mass transfer coefficients, air conditioning, mathematical model.
The Future of Conventional Aircraft Ground Propulsion Systems in Relation to Fuel Consumption and CO2 Emission
IJTEE, volume-13 , Issue 2 (2018), PP 91 - 100
Published: 28 Jan 2018
by Iniobong Edem, Owunna Ikechukwua , Ikpe Aniekan E, Ememobong E. Ikpe from Department of Mechanical Engineering, Coventry University, Priory Street, CV15FB, West Midlands UK Department of Instrumentation and Control, Exxon Mobil Producing Nigeria, Eket, Akwa Ibom State, Nigeria
Abstract: Aircraft spends a minimum of 20 minutes using its main engine to taxi from the airport terminal gate to the runway, where the aircraft takes-off and similarly to the terminal gate after landing. During taxi operation, aircraft burns a lot of fuel, generates large quantity of emissions and the engine in the process of taxiing is exposed to damage due to Foreign Object Damage (FOD). This results in huge operational and maintenance cost as well as carbon emission tax which are all at the expense of the airline. EGTS is a recent technology designed to prevent aircraft from using its main engine for taxi operation and this in turn reduces the rate of fuel consumption, slashes carbon emissions and minimises operational and maintenance cost. This paper examines the viability of using EGTS in single engines for taxi operation rather than the aircraft engine. Block fuel savings was calculated for two engine, single engine and hybrid aircraft and it was observed that two engine aircraft using EGTS saved 110kg block fuel, single engine saved 74kg and for hybrid engine the block fuel savings was 50kg. Block fuel savings was calculated for aircraft such as airbus A320, airbus A380, Cessna 172 and A600ST and it was observed that EGTS is more compatible with airbus A320 but was not recommended for A600ST and A380 due to extra weight implication and for Cessna 172, EGTS was not necessary because the aircraft weight is low and consumes less fuel already. It was observed that the higher the aircraft weight including the extra weight of EGTS, the higher the fuel consumption emission as well as the torque required to overcome drag force when the aircraft operates in air. CO2 emission was also calculated for aircraft with EGTS and aircraft without installation, the result for aircraft with EGTS showed 797.56kg reduction of CO2 emission when compared to aircraft without EGTS. Comparably, EGTS was proven to be viable in terms of fuel savings, CO2 emissions, operational and maintenance cost than its contemporary Ground Propulsion Systems (GPS) for single aircraft engines and therefore, was recommended for aircraft in airbus A320 category to help minimise global warming which results from CO2 emission during taxing operations. Key read more... read less...
Keywords: Aircraft, CO2 Emission, Fuel Consumption, Weight, Ground Propulsion, Cost Savings
IJTEE, volume-13 , Issue 2 (2018), PP 81 - 89
Published: 16 Jan 2018
by Bruce Spencer, Feras Al-Obeidat, Omar Alfandib, from University of New Brunswick, Fredericton, Canada Zayed Universty, Abu Dhabi, UAE University of Göttingen, Göttingen, Germany
Abstract: We forecast internal temperature in two homes, using variants of regression with data from the readings of multiple sensors. We use 48 separate models, where each forecasts mean temperatures that will occur in one future 15-minute interval, to compose a forecast for the next 12 hours. The sensors report internal and external atmospheric and environmental conditions such as temperature, pressure, sunlight, rain and wind, as well as evidence of human activity, including CO2 saturation, motion sensors and electrical load from areas within the house and large appliances. The models use both current and historical sensor values, each of which increases the number of predictors in the linear regression model. We use model simplification techniques including forward stepwise regression, principal component regression, and partial least squares regression. In both houses the forecast accuracy is stable; the mean absolute error over 12 hours is less than 1, while the root mean squared error is less than 1.3. Our accuracy compares favorably to previous work. Our work indicates long sensor histories for forecasts in the next 12 hours do not significantly improve accuracy. read more... read less...
Keywords: Smart Home, Linear Regression, Temperature Forecasting
IJTEE, volume-13 , Issue 2 (2018), PP 75 - 80
Published: 04 Jan 2018
by M. M. Rahman, H. Bhowmik, S. Talukdar from Department of Mechanical Engineering, University of Saskatchewan, Canada Department of Mechanical Engineering, DUET, Gazipur, Bangladesh
Abstract: Three dimensional numerical models were developed to make prediction free convection heat transfer at steady state condition from radial flow heat sink. The air was considered as the medium of heat transfer. In radial flow heat sink, heat conducts through base in radial pattern and is uniformly transported to the fins. The Tagucy method was used to investigate the effect of several design parameters such as fin length, fin height, number of fins and heat sink base radius on heat transfer. There are five factors and four levels on each factor were chosen. Sixteen types of model were analyzed to obtain total heat transfer for each model. The result was used to estimate the optimum designed values of the parameters affecting the heat sink efficiency. The reproducibility of the optimum design value was verified. The average rate of heat transfer of optimum model was increased by more than 50 % than the reference model. Finally, the heat transfer data of radial flow heat sink were correlated of several outer radius by an equation. read more... read less...
Keywords: Natural convection, Laminar flow, Radial flow, Heat transfer, Optimization
IJTEE, volume-13 , Issue 1 (2018), PP 67 - 74
Published: 24 Dec 2018
by Hassan S. Ghalib, Muneer A. Ismael from Mechanical Engineering Department, Engineering College, University of Basrah, Basrah, Iraq
Abstract: This paper investigates the double diffusive natural convection in a partially porous layered enclosed cavity with a thermally conductive square body. The horizontal walls are thermally insulated, the left wall adds heat isothermally into the porous layer, while the right wall is cooled isothermally. The center of the square conductive body is positioned in the center of the cavity in such a way it lays on the porous-fluid interface. The governing equations have been solved using up-wind scheme finite difference method. The Parndtl number, thermal conductivity ratio of the body to fluid, Darcy number, aspect ratio of the square body to the cavity sides have fixed at 6.26, 1, 10-3, 0.5, respectively. The study has been governed by three parameters namely, Lewis number (Le = 1–50), buoyancy ratio (-10 – 10), and Rayleigh number (103 - 106 ). The results have showed that the mass diffusivity ratio, which takes into account non-unity tortuosity ratio (Deff/D = 0.53) has a significant effect on the mass transfer than the unity value. It is found also that Sherwood number is minimal when the buoyancy ratio equals to -0.5, otherwise, it increases with increasing the absolute value of the buoyancy ratio. read more... read less...
Keywords: Double-diffusive, partitioned cavity, porous medium, inner body, finite difference
Numerical Simulation of Heat Transfer during Solidification of Al–Cu Alloy Ingots Cast in a Cylindrical Mold for Different Conditions
IJTEE, volume-13 , Issue 1 (2018), PP 59 - 66
Published: 24 Dec 2018
by Farouk M. Mahdi , Sami R. Aslan, Mahmud H. Ali from Department of Mechanical Engineering, College of Engineering, Tikrit University, Tikrit, Iraq Electronic and Control Engineering Technology, Technical College Kirkuk, Kirkuk, Iraq Department of Mechanical Engineering, College of Engineering, Kirkuk University, Kirkuk, Iraq
Abstract: In this paper, two dimensional numerical simulation of heat transfer during solidification of Al- 4.5 wt. % Cu alloy cast in a cylindrical mold was carried out to specify the optimum solidification conditions. The mold has the dimensions of 150 mm height, 38 mm outer radius, and 8 mm thickness. Four cases were studied for the solidification process; first case is the solidification in the mold without applying any thermal effects at four different mold temperatures of 25, 50, 100 and 200 Ԩ respectively. The second case is insulating the cast from the top. The third case is insulating the upper portion of the mold wall. The last case is adding heat to the upper portion of the mold wall for specific time. For the last three cases, the mold temperature is set to 25Ԩ. The results have shown that the increase in mold temperature only increases the solidification time and it does not significantly affect the temperature distribution and the final cast shape. Insulating the top of the mold made the last solidification region to be at the top of the cast, which leads to get ingot free from the secondary cavity. Insulating a portion of the upper wall of the mold made the cast surface to be more homogeneous with smallest secondary cavity. Heat addition to a portion of the upper wall of the mold leads to obtain a cast with approximately flat surface that is free from secondary cavity in addition to the primary cavity. read more... read less...
Keywords: Al 4.5 wt. % Cu alloy ingot casting; heat transfer; numerical simulation; cylindrical metal mold
IJTEE, volume-13 , Issue 1 (2018), PP 49 - 58
Published: 26 Nov 2018
by Lars Henrik Nielsen, Mattia Baldini, Klaus Skytte, Cristian Hernán Cabrera Pérez, Eduardo Carrajero García, Diego Lopez Barrio, Lucía González Cuadrado, Alberto Rodríguez Rocha from Technical University of Denmark (DTU), Copenhagen, Denmark Investigación, Desarrollo e innovación en energía, Madrid, Spain COBRA Technology & Innovation, Madrid, Spain
Abstract: Concentrating Solar Power (CSP) plants utilize thermal conversion of direct solar irradiation. A trough or tower configuration focuses solar radiation and heats up oil or molten salt that subsequently in high temperature heat exchangers generate steam for power generation. High temperature molten salt can be stored and the stored heat can thus increase the load factor and the usability for a CSP plant, e.g. to cover evening peak demand. In the HYSOL concept (HYbrid SOLar) such configuration is extended further to include a gas turbine fuelled by upgraded biogas or natural gas. The optimised integrated HYSOL concept, therefore, becomes a fully dispatchable (offering firm power) and fully renewable energy source (RES) based power supply alternative, offering CO2-free electricity in regions with sufficient solar resources. The economic feasibility of HYSOL configurations is addressed in this paper. The analysis is performed from a socio- and private- economic perspective. In the socio-economic analysis, the CO2 free HYSOL alternative is discussed relative to conventional reference firm power generation technologies. In particular the HYSOL performance relative to new power plants based on natural gas (NG) such as open cycle or combined cycle gas turbines (OCGT or CCGT) are in focus. In the corporate-economic analysis the focus is on the uncertain technical and economic parameters. The core of the analyses is based on the LCOE economic indicator. In the corporate economic analysis, NPV and IRR are furthermore used to assess the feasibility. The feasibility of renewable based HYSOL power plant configurations attuned to specific electricity consumption patterns in selected regions with promising solar energy potentials are discussed. read more... read less...
Keywords: Feasibility analysis; CSP, Hybridization; Storage; Steam turbine; Firm power; HYSOL; OCGT; CCGT
Glass Properties Selection Effect on LEED Points for Core and Shell High Rise Residential Building in Jordan, Ammar Alkhalidi, Hasan Jarad, Mohammad Juaidy
IJTEE, volume-13 , Issue 1 (2018), PP 29 - 35
Published: 27 Jul 2018
by Ammar Alkhalidi, Hasan Jarad, Mohammad Juaidy from Department of Energy Engineering, German Jordanian University, P.O. Box 35247, Amman 11180 Jordan Mechanical Engineering, JEA Associate engineer, Arabtec Jardaneh Engineers and Architects, Amman, Jordan
Abstract: Green building concept is flourishing in developing countries due to the high-energy cost. To meet the green building requirement, this paper investigate the effect of glass properties on 4 and 20 story building total, heating and cooling, loads for variable glass-wall ratios using HAP4.5 . The ratios considered are 20%, 40%, 60%, 80% & 100% glass to wall. The simulations were carried out for both building under moderate climate, Amman, Jordan was the selected city from this climatic zone. The glass overall heat transfer (U-value) & shading coefficient (S.C) are paired in nine combinations, these pairs are called Combination Number (CN). Combination Number simulate all range of glass properties, CN 1 is the worst case to 9 the best glass properties. Results showed that the minimum impact of glass properties was on 20-percentile glass to wall ratio and maximum at 100 Percentile. On the other hand, a Maximum of 10 LEED point could be achieved in the 20-percentile and 16 point in the case of 100-persentile for both 20 and 4 story building. Data found in this paper where formulated in the following equations with R2 = 0.949.4 Story Total Load = 915514 - (63546 * CN) + (9770 * Glass to wall) 20 Story Total Load = 7638346 - (540386 * CN) + (84090 * Glass to wall) read more... read less...
Keywords: Green Building, LEED Points, Glass Properties Effect
IJTEE, volume-13 , Issue 1 (2018), PP 23 - 28
Published: 27 Jul 2018
by H.O. Egware, U.P. Onochie, O.O. Ighodaro from Department of Mechanical Engineering, University of Benin, Benin City, Nigeria National Centre for Energy and Environment, Energy Commission of Nigeria, University of Benin, Benin City, Nigeria
Abstract: Wind is a renewable energy resource by nature. It is clean, abundant, inexhaustible and environmentally friendly. Essentially, this study investigated the prospects of wind energy for power generation in University of Benin. Wind data from Jan 31st – Dec 31st 2013 (at 10m height) was collected from National Centre for Energy and Environment, University of Benin. Accordingly, the annual and monthly wind speed and density are estimated using the 2- parameter Weibull probability density function. From the analysis, results obtained shows that the highest mean wind speed of 1.975m/s occurred in March and the lowest monthly mean speed of 0.977m/s occurred in November. Also, the annual mean wind speed is 1.496m/s while the annual mean power density based on Weibull distribution function is 2.692W/m2 . Further results shows that the mean annual most probable wind speed and wind speed carrying maximum energy are 1.535m/s and 1.761m/s respectively. Thus, it is recommended that the institution can tap on the available wind power potential to augment its power supply. read more... read less...
Keywords: Prospects, wind energy potential, Weibull distribution, wind speed, wind power density.
IJTEE, volume-13 , Issue 1 (2018), PP 17 - 22
Published: 27 Jul 2018
by Bilal A. Akash from American University of Ras Al Khaimah, Ras Al Khaimah, United Arab Emirates
Abstract: Lignin can be considered as a clean source of renewable energy, which may be a substitute to fossil fuel and thus reduce some of the environmental pollution. This paper presents a review of the thermal process of depolymerization of lignin; which results in production of oil and gaseous fuels from such important renewable energy source. Also, thermal hydro-cracking of lignin enhances the liquefaction of other solid fossil fuels such as coal, by producing intermediates which then react further with coal producing lower molecular weight material, which is more desirable. read more... read less...
Keywords: Lignin, depolymerization, thermal hydrocrackingd
IJTEE, volume-13 , Issue 1 (2018), PP 7 - 12
Published: 27 Jul 2018
by N. Adam, A. Shanableh from Department of Civil and Environmental Engineering University of Sharjah, Sharjah, United Arab Emirates Research Institute of Sciences and Engineering, University of Sharjah, PO Box 2727, Sharjah, United Arab Emirates
Abstract: The purpose of this study was to assess the potential of combining the production of three types of biofuels (i.e., biodiesel, bioethanol, and biogas) from Nannochloropsis sp. microalgae. Cellulase enzyme, produced from Trichoderma viride fungi was used to convert algal hydrocarbons into sugars for bioethanol production and to improve lipids extraction for biodiesel production. The procedure for producing the three biofuels consisted of initially mixing predetermined quantities of cellulose with the algae to hydrolyze the complex hydrocarbons and produce sugars, followed by oil extraction from the hydrolyzed algae, and finally producing biogas through co-digesting the hydrolyzed and oil-extracted algae residual with wastewater treatment sludge. Without enzyme, the total sugar yield following hydrolysis for 6 hours with distilled water at 37°C and pH 5 reached 38 mg/g algae. Using the enzyme, total sugar production increased in the range of 42 mg/g algae to 74 mg/g algae with increasing enzyme use. Similarly, the reducing sugar production increased from 36 mg/g algae without enzyme to 60 mg/g algae with increasing enzyme dose. Following hydrolysis, the lipids yield reached 59% of the extracted algae weight, which represents almost all of the lipids in the algae. The residual algae mixed with sludge generated significant amounts of biogas in excess of the quantities generated by sludge alone. The results demonstrated the technical feasibility of producing three biofuels from algae; however the economic aspects of the process require significant further careful consideration. read more... read less...
Keywords: Biofuels, Biogas, Biodiesel, Ethanol, Enzymatic Hydrolysis, Sugars, Oil, Renewable Energy, Microalgae.
Impact of Date Palm Seed Size on Biogas Production from Date Seeds/Wastewater Treatment Sludge Mixtures
IJTEE, volume-13 , Issue 1 (2018), PP 1 - 6
Published: 27 Jul 2018
by W. Radeef, A. Shanableh, T. Merabtene from Department of Civil and Environmental Engineering, University of Sharjah, Sharjah, United Arab Emirates Research Institute of Sciences and Engineering, University of Sharjah, PO Box 2727, Sharjah, United Arab Emirates
Abstract: Biogas in the form of methane can be produced from wastewater treatment sludge mixed with a variety of biodegradable organic feedstocks through anaerobic digestion. In this study, biogas was produced from date palm seeds, which are locally available, and wastewater treatment sludge mixtures. The objective of the study was to assess the effect of date palm seed additives with different sizes on biogas production from the mixtures. In the study, two locally available types of date seeds, Khalas and Khudari, were anaerobically co-digested with wastewater treatment sludge in 50 mL serum bottles under mesophilic conditions. Date seeds with three different sizes; 1.18– 3.75 mm, 0.6 –1.18 mm; and 0.425 – 0.6 mm, were added to the sludge at date seeds to sludge total solids (TS) weight ratios of 0%, 2.5%, 5%, 7.5%, and 10%. The experimental results confirmed that the addition of date seeds significantly enhanced biogas production up to 20% to 30%. The results indicated that the date seed size slightly affected biogas production, with the order of cumulative biogas production and biogas production rates, expressed in terms of date seed sizes, being as follows: 0.425 – 0.6 mm > 0.6 – 1.18 mm > 1.18 – 3.75 mm. However, the results showed no major difference in biogas production between the two different date seed types read more... read less...
Keywords: Khalas Date Seed, Khudari Date Seed, Wastewater Sludge, Biogas Production, Methane Production, Biofuel