Ayhan Demirbaş

Ayhan Demirbaş

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Publications (437)
Article
Full-text available
Shale gas is essentially non-traditional natural gas (NG). Shale gas can be considered an unusual alternative energy source. Shale gas production is a method of obtaining the NG trapped between deep underground rocks. Shale gas production is not economical, except for horizontal drilling and hydraulic fracturing methods. Advanced analysis of shale...
Article
Full-text available
Petroleum coke is often shortened as pet coke. Petroleum coke or pet coke is a product obtained from oil of all kinds during the oil refining process. Petroleum coke is a carbon-rich solid originating from petroleum refining and is obtained by cracking process. Petroleum coke is a byproduct of the coking unit, a residual fuel upgrader. The coke qua...
Article
Full-text available
Hydrocarbon compounds are formed by carbon and hydrogen elements. The higher heating values (HHVs) of the hydrocarbon compounds can be calculated based on the carbon (C) and hydrogen (H) contents of the chemical structures. HHVs (MJ / kg) as a function of the carbon (C) and hydrogen (H) fractions of N-saturated hydrocarbons can be calculated by the...
Article
This study presents a preliminary assessment of biodiesel production from waste sources available in the Kingdom of Saudi Arabia (KSA) for energy generation and solution for waste disposal issues. A case study was developed under three different scenarios: (S1) KSA population only in 2017, (S2) KSA population and pilgrims in 2017, and (S3) KSA popu...
Article
Bioenergy is an effective energy form used by developing countries. It covers about 38% of the energy consumed primarily obtained from the biomass in about 13% of the world. Due to the energy production costs, much attention has currently been paid on alternative bioenergy sources in the developing countries. Biofuels may be used instead of fossil...
Article
Although Saudi Arabia is producing high gross national income per year in the Jeddah city, the sewage treatment and disposal systems does not meet the needs of people sufficiently. The disposal and industrial solid waste treatment and the collection of municipal sewage have been creating problems for a long time in Jeddah. The predictions showed th...
Article
Full-text available
The environmental impacts of petroleum are often negative because they are toxic to almost all lifestyles, and there is a possibility of causing climate change. Oil pollution in the air and in the water can be toxic and dangerous to the human body. Preliminary researchers have thoroughly studied and discussed the methods of treatment of oily wastew...
Article
In this study, the kinetics of chemical reaction was studied based on the correlation between the rate of degradation of glucose by the microalgae and the rate of hydrogen gas formation. Bio-photolysis was carried out algal strain Chlorella vulagaris in order to produce hydrogen gas (H2) using glucose as an initial substrate. Algal strain C. vulgar...
Article
The aim of this study is to determine the impact of domestic petroleum demand volatilities on economic growth in Saudi Arabia. It is suggested to use the strategy statistical tools and estimation techniques necessary to achieve this aim. A demand and supply strategy can be developed to predict the demand for petroleum products correctly. The econom...
Article
Full-text available
Sewage sludge is obtained from wastewater treatment in sewage treatment plants. The sludge consists of two basic forms, sludge and secondary sludge, also known as activated sludge in the case of activated sludge process. Municipal sewage sludge (MSS) or only sewage can be a solid, semi-solid, or liquid muddy residue. It contains mainly proteins, su...
Article
Unconventional hydrocarbon applications have been growing rapidly in recent years. Unconventional oil can be produced from oil sands, oil shale, extra heavy oil, gas to liquids (GTL), and other liquids. Conventional fossil energy will not be enough to meet the continuously increasing need for energy in the future. In this case, renewable energy sou...
Article
The aim of this study was to determine the quality and applications of liquid oil produced by thermal and catalytic pyrolysis of polystyrene (PS) plastic waste by using a small pilot scale pyrolysis reactor. Thermal pyrolysis produced maximum liquid oil (80.8%) with gases (13%) and char (6.2%), while catalytic pyrolysis using synthetic and natural...
Article
Algae are mainly composed of lipids, carbohydrates, proteins, and nucleic acids. Microalgae can be converted into liquid and gaseous products by direct liquefaction, pyrolysis, and supercritical water pyrolysis. The effect of pyrolysis temperature on the yield of bio-oil from algae samples was reviewed. The yield of bio-oil from pyrolysis of the sa...
Article
Full-text available
Municipal sewage sludge (MSS) is a biowaste formed during wastewater treatment and the sewage sludge can be obtained from industrial wastewater treatment system. The sewage sludge contains a variety of organic and inorganic compounds, mainly lipids, proteins, sugars, detergents, and phenols. The MSS contains a significant amount of lipid fraction c...
Article
Depletion of fossil fuel resources and stringent emission mandates has spurred the search for improved diesel engines performance and cleaner combustion. One of the best approaches to solve these issues is to use biodiesel/diesel additives. The effects of biodiesel/diesel additives on the performance and emissions of diesel engines were comprehensi...
Article
Oil price volatility shows the degree of rise or fall in oil prices over time. The price of crude oil is highly influenced by the fluctuations in supply–demand gap and global macroeconomic and geopolitical conditions. The Organization of the Petroleum Exporting Countries (OPEC) plays an important role in the global oil supply and demand. The oil pr...
Article
Crude oils are composed of hundreds of different hydrocarbon molecules, which are separated through the process of refining and small quantities of oxygen, sulfur, nitrogen, vanadium, nickel, and chromium. An oil refinery is a group of manufacturing plants that are used to separate petroleum into valuable fractions. Oil refining is one of the most...
Article
Full-text available
This paper aims at discussing the renewable energy resource facilities in delivering parts of the energy needs in Kingdom of Saudi Arabia (KSA). Renewable energy resources include biomass, hydraulic, solar, wind, geothermal, wave, tidal, biogas, and ocean thermal energy. Biomass is used to meet a variety energy needs, including generating electrici...
Article
The objectives of this study are (a) to develop a comprehensive understanding of the transportation sector, including energy consumption by all subsectors and (b) to study the key factors that drive the fuel and energy demand. The study will focus on the transportation sector as a key component of the economy, and the engine for economic developmen...
Article
Saudi Arabia is the world’s top oil exporter and producer. Saudi Arabia is the largest oil-consuming nation in the Middle East. Gasoline and diesel fuel in the Kingdom cost about 16 cents and 6 cents per liter, respectively. More oil for internal consumption will lead to less oil for exports. Saudi Arabia could, by the late 2020s, consume more oil...
Article
Biogas is produced by anaerobic (oxygen free) digestion of organic materials such as sewage sludge, animal waste, and municipal solid wastes (MSW). As sustainable clean energy carrier biogas is an important source of energy in heat and electricity generation, it is one of the most promising renewable energy sources in the world. Biogas is produced...
Article
Millions of Muslims from all over the world visit the Holy Cities of Saudi Arabia: Makkah and Madinah every year to worship in form of Pilgrimage (Hajj) and Umrah. The rapid growth in local population, urbanization, and living standards in Makkah city along with continually increasing number of visitors result in huge municipal solid waste generati...
Article
In recent years, attention has been given to obtaining methane gas from natural gas hydrates (NGHs) sediment; but its production, economics, and safety are still far away from being commercially viable for many years, and so more research is needed. NGHs are nonstoichiometric crystalline solid compounds that form from mixtures of water molecules an...
Article
Oil shale is a complex fossil material that is composed of organic matter and mineral matrix. The thermal decomposition of the organic matter generates liquid and gaseous products. Oil shale is a porous rock containing kerogen, an organic bituminous material. Kerogen is a solid mixture of organic compounds that is found in certain sedimentary rocks...
Article
Vegetable oils and animal fats comprise of triglycerides which are formed by fatty acids. Some fatty acids, particularly those having the unsaturated bond are not easy to purify. For this reason, it is not possible to determine exactly the higher heating values (HHVs) of unsaturated fatty acids experimentally via the correct way. HHVs of fatty acid...
Article
Kingdom of Saudi Arabia (KSA) has the fourth largest natural gas (NG) reserves in the world. One third of these reserves are located in the Ghawar region of Eastern Province. NG production is controlled tightly due to close conjunction with oil production until recently. KSA’s NG production of 85 billion cubic meters in 2015 from 70 billion cubic m...
Article
This paper aims to determine the waste-to-energy (WTE) and recycling value of municipal solid waste (MSW) for developing an integrated solid waste management (ISWM) system for Lahore, the second largest city in Pakistan. The overall generated waste in Lahore contains 58% organic waste, 25% recyclables, and 17% others. The recyclable materials inclu...
Article
This study deals with the pyrolysis of waste tires supplied from the transport industry. The base material of tire is latex, which is derived from natural rubber trees. Nowadays rubber (Hevea brasiliensis) is a fast-growing tropical tree crop, which is being cultivated for latex and ultimately for tire production. Waste tires can be recycled for en...
Article
Full-text available
The Kingdom of Saudi Arabia has rich geothermal energy resources. In Saudi Arabia, the studies on geothermal resources exploration were started in 1980. Saudi Arabia is among the most geothermally active countries in the Middle East. The geothermal power plants are not yet installed in Saudi Arabia. Some direct-use low-grade geothermal applications...
Article
Municipal solid waste (MSW) mainly comprises organics, paper, glass, plastics, metals, wood, etc. Rapid industrialization, high population growth rate, and fast urbanization have resulted in increased levels of pollution and MSW in Saudi Arabia. The amount of waste has been steadily increasing due to increasing human population and urbanization. Re...
Article
Full-text available
Charcoal products can be produced from biomass sources such as charcoal from wood, woody agricultural products, the biogenic fraction of municipal wastes, nut shells, etc. The liquid and gaseous fractions obtained from biomass are a valuable fuel source; however, the solid fraction (charcoal) has the recovery potential of carbon black or as carbon...
Chapter
Energy affects all aspects of modern life. Energy sources will play an important role in the world’s future. Because of the exponential growth of the world population, demand for energy is increasing at an exponential rate. Current examples of these priorities include: reducing greenhouse gas emissions, improving the energy efficiency of our homes,...
Chapter
General optimization concept is desired factors in maximizing and minimizing undesired effects, the most cost-effective under given constraints or find an alternative with the highest achievable performance.
Chapter
Unconventional energy sources cover unusually unconventional energy, with little or no unused, inactive cases and the energy resources available waste form. Figure 3.1 shows unconventional energy sources. For example; extra heavy oil, heavy crude oil and no 4–6 fuel oils are unconventional energy sources because they are used in small amounts or fo...
Article
Wax deposition is one of the chronic problems in the petroleum industry. The various crude oils present in the world contain wax contents of up to 32.5%. Paraffin waxes consist of straight chain saturated hydrocarbons with carbons atoms ranging fromC18 to C36. Paraffin wax consists mostly with normal paraffin content (80–90%), while, the rest consi...
Article
Crude oil contains four chemical group classes, namely saturates, aromatics, resins, and asphaltenes (SARA fractions). Resins fraction of crude oil comprises polar molecules often containing heteroatoms such as nitrogen, oxygen, or sulfur. Resin is a heavier fraction than aromatics and saturates. Resins are composed of fused aromatic rings with bra...
Article
Currently, more than half of the oil reserves (53.3%) in the world are in the form of restorable oils such as heavy oil, extra heavy oil, oil sand, tar sands, oil shale, and bitumen. Heavy oil is one of the petroleum oil varieties that contain long chain hydrocarbons. All types of heavy oils contain asphaltenes and thus are considered very dense su...
Article
Full-text available
Biodiesel is an alternative to petroleum-based fuels derived from a variety of feedstocks, including vegetable oils, animal fats, and waste cooking oil. At present, biodiesel is mainly produced from conventionally grown edible oils such as soybean, rapeseed, sunflower, and palm. The cost of biodiesel is the main obstacle to commercialization of the...
Article
A crude oil has four main constituents: saturates, aromatics, resins, and asphaltenes. The asphaltenes in crude oil are the most complex and heavy organic compounds. The classic definition of asphaltenes is based on the solution properties of petroleum residuum in various solvents. Asphaltenes are a solubility range that is soluble in light aromati...
Article
A solid waste management system based on the 3R principle: reduce, reuse, and recycle. There are two major recycling methods for conversion of plastic wastes to synthetic fuels: (a) pyrolysis in absence and presence of catalyst and (b) thermal and/or catalytic cracking. Pyrolysis is a complex series of chemical and thermal reactions to decompose or...
Article
In general, vegetable oils are triglycerides, which consist of 18-carbon fatty acids. There is no boiling point of vegetable oils, because oils start to decompose when heated to a certain temperature after removing smoke. The smoke point is the temperature at which the oil is decomposed and where possibly toxicological relevant compounds are formed...
Article
Fuel oils (numbers 1-6) are fractions of crude oil. The boiling point and carbon chain length of the fuel increases with fuel oil number. Viscosity increases with the number, and is needed to flow the heated heavy oil. No. 4 fuel oils are used as burner fuel for domestic and industrial heating and have to raise steam for power generation and marine...
Article
Surfactant flooding is a well-known enhanced oil recovery (EOR) technique that has been used worldwide for decades. The surfactant can meaningful lower interfacial tension and change the wetting properties. Surfactant related recovery processes are of increasing interest and importance because of high oil prices and the urge to meet energy demand....
Article
Full-text available
Gasoline is a petroleum-derived liquid that is used primarily as a fuel in internal combustion engines (ICE), particularly spark ignition Otto Engine. Gasoline is a blend of hydrocarbons with some contaminants, including sulfur, nitrogen, oxygen, and certain metals. The four major constituent groups of gasoline are olefins, aromatics, paraffins, an...
Article
The aim of this study was to estimate mathematical relationships between higher heating value (HHV) and specific gravity of petroleum fuels. The HHV is an important property defining the energy content of petroleum related fuels. The specific gravities of petroleum fuels generally range from 0.56 to 0.92 (based on the specific gravity of pure water...
Article
Turkey is at the crossroads of Europe and several volatile and strategically and economically important regions, including the Caspian Sea basin region, the Middle East, and Russia. Turkey is the most important part of Caspian Sea Basin-Middle East-Turkey triangle. Its location on two continents plays a central part in Turkish history and gives the...
Article
Full-text available
Recycling and rerefining are the applicable processes for upgrading of petroleum-based wastes by converting them into reusable products such as gasoline, diesel fuel, and heavy oil. Possible acceptable processes are cracking and pyrolysis. The aim of the study was to obtain diesel fuel from waste lubricating oil by pyrolitic distillation method, wh...
Article
Most the lubricant oils are generally obtained from petroleum resources. Waste lubricating oil can be converted into valuable fuel products by refining and treating processes. Recycling is the applicable process for upgrading of petroleum-based wastes by converting them into reusable products such as gasoline, diesel fuel, and heavy oil. Possible a...
Article
In this review, strategies for crude oil desulfurization are evaluated by reviewing desulfurization literature. The most important characteristics of crude oil that affect the market price are its sulfur content and gravity. Low sulfur content of crude oil is particularly preferred. Petroleum includes crude oil, natural gas, and heavy oil. Petroleu...
Article
Evaluation of Oriental beech (Fagus orientalis L.) was investigated with aspect of thermo-chemical conversion to obtain bio-char, bio-oil and gaseous. When the pyrolysis temperature increased, the bio-char yield decreased. A high temperature and smaller particles increase the heating rate resulting in a decreased bio-char yield. The bio-char obtain...
Article
Milled giant fennel (Ferula orientalis L.) stalks were treated in supercritical solvents in the presence of catalyst in a high pressure reactor. Effects of process variables including temperature (from 240 to 320 oC), solvent (2-propanol, 2-butanol, and acetone), catalyst (Na2CO3, NaOH, and ZnCl2), particle size (from 0.224>Dp>0.150 to 0.850>Dp>0.4...
Article
Eremurus spectabilis samples were liquefied in organic solvents (methanol, ethanol and acetone) with (sodium hydroxide and ferric chloride) and without catalyst in a cylindrical reactor at temperatures of 270, 290 and 310 °C under supercritical conditions. The effects of liquefaction parameters such as temperature, catalyst and solvent on product y...
Data
The main objective of this study was to remove Cu and Ni ions from aqueous solution by using fly ash, an industrial solid waste of the sugar industry and commercial activated carbon at equilibrium, which follows Langmuir and Freundlich adsorption isotherms. In order to identify influential parameters and to evaluate their interactions, effects of t...
Article
Algae containing 30–75% of lipid by dry basis can be called oilgae. All microalgae species produce lipid however some species can contain up to 70% of their dry weight. Microalgae appear to be the only source of renewable biodiesel that is capable of meeting the global demand for transport fuels. Biodiesel production by using oilgae is an alternati...
Article
Microalgae are unique photosynthetic organisms given that they accumulate storage lipids in substantial quantities and thrive in high salinity water. Algae cultivation is flexible on water quality. Many species of algae thrive in seawater, water from saline aquifers, or even wastewater from treatment plants. Photosynthesis, algae use solar energy t...
Article
The main objective of education is to prepare people for future. Energy is the indispensable part of every society and it reflects the living standards and development level of the society. The energy concept, introduced four centuries ago as a physics concept, is used today in many diverse fields like biology, chemistry, geography, economics etc....
Article
Currently, fossil fuels such as oil, coal and natural gas represent the prime energy sources in the world. However, it is anticipated that these sources of energy will deplete within the next 40-50 years. Moreover, the expected environmental damages such as the global warming, acid rain and urban smog due to the production of emissions from these s...
Article
The purpose of the present paper is to evaluate the potentiality of the wood oil of Oriental spruce (Spruce orientalis) for biodiesel production. Two methods have been applied for obtained wood oil with and without solvent such as separation of crude tall oil from sulfate soaps by Kraft pulping process. Production of biodiesel from wood oil follows...
Article
In this study, waste management concept, waste management system, biomass and bio-waste resources, waste classification, and waste management methods have been reviewed. Waste management is the collection, transport, processing, recycling or disposal, and monitoring of waste materials. A typical waste management system comprises collection, transpo...
Article
The cost of biodiesels varies depending on the feedstock, geographic area, methanol prices, and seasonal variability in crop production. Most of the biodiesel is currently made from soybean, rapeseed, and palm oils. However, there are large amounts of low-cost oils and fats (e.g., restaurant waste, beef tallow, pork lard, and yellow grease) that co...
Article
Algae are the fastest-growing plants in the world. Industrial reactors for algal culture are open ponds, photobioreactors and closed systems. Algae are very important as a biomass source. Algae will some day be competitive as a source for biofuel. Different species of algae may be better suited for different types of fuel. Algae can be grown almost...
Article
Currently, fossil fuels such as oil, coal and natural gas represent the prime energy sources in the world. However, it is anticipated that these sources of energy will deplete within the next 40–50 years. Moreover, the expected environmental damages such as the global warming, acid rain and urban smog due to the production of emissions from these s...
Article
Green tea seed (Camellia sinensisL. Kuntze) oil was used in this work. The tea seed oil contains more than 84% unsaturated fatty acid, such as oleic acid (62.5% by weight), linoleic acid (18.1% by weight) and linolenic acid. The biodiesel from tea seed oil in itself is not significantly different from biodiesel produced from vegetable oils. However...
Article
The aim of this study is to investigate the algae production technologies such as open, closed and hybrid systems, production costs, and algal energy conversions. Liquid biofuels are alternative fuels promoted with potential to reduce dependence on fossil fuel imports. Biofuels production costs can vary widely by feedstock, conversion process, scal...
Article
Three processes have been proposed for dissociation of methane hydrates: thermal stimulation, depressurization, and inhibitor injection. The obvious production approaches involve depressurization, heating and their combinations. The depressurization method is lowering the pressure inside the well and encouraging the methane hydrate to dissociate. I...
Article
Gas hydrates are ice-like crystalline solids that form from mixtures of water and light natural gases such as methane, carbon dioxide, ethane, propane and butane. Methane was the dominant component among other hydrocarbon gases in the sediments. Gas hydrates, potentially one of the most important energy resources for the future. Methane gas hydrate...
Article
Biodiesel is a natural, renewable transportation fuel. Biodiesel is the best candidate for diesel fuels in diesel engines with no alterations. Biodiesel is a nontoxic, biodegradable alternative to petroleum diesel that substantially reduces air pollution. Biodiesel fuel typically comprises lower alkyl fatty acid (chain length C14-C22), esters of sh...
Article
Biomass can be converted into useful bio-fuels and bio-chemicals via biomass upgrading and biorefinery technologies. Biomass upgrading processes include fractionation, liquefaction, pyrolysis, hydrolysis, fermentation, and gasification. The benefits of an integrated biorefinery are numerous because of the diversification in feedstocks and products....
Article
Petroleum plays a very important role in foreign policies and their international relations of Caspian and Middle East countries. The Middle East itself produces 32% of the world's oil, but even more impressive is they have 64% of the total proven oil reserves in the world. Turkey is at the crossroads of Europe and several volatile, strategically,...
Article
In the present work, oils from the leaves and fruits of bay laurel, Laurus nobilis L (Lauraceae) were converted into fatty acid methyl esters or biodiesel by transesterification reaction in supercritical methanol without using the catalyst. Experiments have been carried out in a pressure-proof reaction vessel (autoclave) preheated at 493, 523, and...
Article
Biomass may be converted to more useful fuel and chemicals via thermochemical decomposition and biological digestion. Thermochemical conversion processes include three sub-categories: pyrolysis, gasification, and direct liquefaction. Two biomass conversion processes using water have been studied: hydrothermal upgrading under subcritical water and s...
Article
Turkey has always been one of the major agricultural countries in the world. The importance of agriculture is increasing as biomass energy becomes one of the major resources in Turkey. Current disposal methods for these agricultural residues have caused widespread environmental concerns. Achieving solutions to environmental problems requires long-t...
Article
Hazelnut shell was liquefied directly in water at 530–710 K and in glycerol and alkaline (10% sodium carbonate) glycerol at 523–603 K temperature range. Thermal degradation of biomass, cellulose, hemicelluloses, and products were formed as well as a solid residue of char in low temperatures. In the liquefaction process, the micellar-like broken dow...
Article
In this study, oils, micronutrients and heavy metal contents of tomato seeds and tomato (Lycopersicon esculentum) fruits from different Turkish resources were determined. The tomato seed oil contains more than 84% unsaturated fatty acids, such as oleic acid, linoleic acid and linolenic acid. The fatty acid composition of tomato seed oil was similar...
Article
Full-text available
The aim of this study is to obtain diesel-like fuel from waste lubrication engine oils by pyrolitic distillation method, which can be used in diesel engines. With this aim in mind, waste engine oil is collected in a tank, and it is purified from contaminants such as dust, heavy carbon soot, metal particles, gum-type materials and other impurities b...
Article
World annual petroleum consumption and vegetable oil production is about 4.018 and 0.107 billion tons, respectively. Vegetable oils from bio-renewable oil seeds can be used when mixed with diesel fuels. Vegetable oils can be used as fuels for diesel engines, but their viscosities are much higher than usual diesel fuel and require modifications of t...
Article
In this study, the effect of temperature on the yield of hydrogen from two mosses (Polytrichum commune and Thuidium tamarascinum) and two algae (Cladophora fracta and Chlorella protothecoid) by pyrolysis and steam gasification were investigated. In each run, the main components of the gas phase were CO2, CO, H2, and CH4. The yields of hydrogen by p...
Article
Gas hydrates are crystalline solids that form from mixtures of water and light natural gases such as methane, carbon dioxide, ethane, propane, and butane. The Black Sea is the world's most isolated sea. Methane exists as gas hydrates or methane clathrate form in the Black Sea. Gas hydrates potential in the Black Sea is investigated as a source of m...
Article
The conversion of wood into bio-fuels and bio-chemicals is technically feasible. Wood valorization processes include fractionation, pyrolysis, hydrolysis, fermentation, and gasification. Fast pyrolysis utilizes wood biomass to produce a product that is used both as an energy source and a feedstock for chemical production. The bio-oils from wood pyr...
Article
In this study, characterization of Oriental beech wood (Fagus orientalis) with Turkish origin was investigated with aspect of structural, chemical, and thermochemical conversional properties. Liquefaction, supercritical fluid extraction, and pyrolysis of the samples were studied to obtain liquid fuel oils and chemicals. Beech wood was partly conver...
Article
Fuel cells are inherently ultra clean, highly efficient, and reliable. Biodiesel and methanol can be used in a blend with conventional fuels without engine modification or without being as pure as a fuel. Biodiesel fueled cell is a variation of the proton exchange membrane fuel cell. The biodiesel fueled cell and direct methanol fuel cell are extre...
Article
Today the world is facing three critical problems: (1) high fuel prices, (2) climatic changes, and (3) air pollution. Experts suggest that current oil and gas reserves would suffice to last only a few more decades. Biorenewable liquids are the main substitutes to petroleum-based gasoline and diesel fuel. These fuels are important because they repla...
Article
Comparison with other biomass thermochemical gasification, such as air gasification or steam gasification, the supercritical water gasification can directly deal with the wet biomass without drying, and has high gasification efficiency in lower temperatures. The cost of hydrogen production from supercritical water gasification of wet biomass was se...
Chapter
Billions of years ago the Earth’s atmosphere was filled with CO2. Thus there was no life on the planet. Life on Earth started with Cyanobacterium and algae. These humble photosynthetic organisms sucked out the atmospheric CO2 and started releasing oxygen. As a result, the levels of CO2 started decreasing to such an extent that life evolved on Earth...
Chapter
Continued use of petroleum sourced fuels is nowwidely recognized as unsustainable because of depleting supplies and the contribution of these fuels to the accumulation of carbon dioxide in the environment. Renewable, carbon-neutral transport fuels are necessary for environmental and economic sustainability (Chisti 2007). Biodiesel can be carbon neu...
Article
Bioethanol and biodiesel are two alternative fuels promoted with potential to reduce dependence on fossil fuel imports. Biofuels production costs can vary widely by feedstock, conversion process, scale of production and region. The major economic factor to consider for input costs of biodiesel production is the feedstock, which is about 75-80% of t...
Article
Three processes have been proposed for dissociation of methane hydrates: thermal stimulation, depressurization, and inhibitor injection. The obvious production approaches involve depressurization, heating and their combinations. The depressurization method is lowering the pressure inside the well and encouraging the methane hydrate to dissociate. T...
Article
The world is currently faced with two significant problems: fossil fuel depletion and environmental degradation, which are continuously being exacerbated due to increasing global energy consumption. As a substitute for petroleum, renewable fuels have been receiving increasing attention due a variety of environmental, economic, and societal benefits...
Article
Gas hydrates, potentially one of the most important energy resources for the future. Methane gas hydrates are increasingly considered a potential energy resource. Enormous reserves of hydrates can be found under continental shelves and on land under permafrost. Methane hydrates are widespread in sea sediments hundreds of meters below the sea floor...
Chapter
The world has been confronted with an energy crisis due to the depletion of finite fossil fuel resources. The use of fossil fuels as energy is now widely accepted as unsustainable due to depleting resources and also due to the accumulation of greenhouse gases in the atmosphere. Biomass provides a number of local environmental gains. Biomass resourc...
Chapter
During the last 200 years, developed countries have shifted their energy consumption toward fossil fuels. Renewable energies have been the primary energy source in the history of the human race. Wood was used for cooking and water and space heating. The first renewable energy technologies were primarily simple mechanical applications and did not re...
Chapter
Modern bioenergy involves commercial energy production from biomass for industry, power generation, or transport fuels. Bioenergy is an all-inclusive term for all forms of biomass and biofuels. Green energy is an alternate term for renewable energy used to indicate that the energy is generated from sources considered environmentally friendly. Vario...

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