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Fuel is any material that stores ENERGY that can later be extracted to perform MECHANICAL WORK in a controlled manner .
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Fuel is any material that stores ENERGY that can later be extracted to perform MECHANICAL WORK in a controlled manner. Most fuels used by humans undergo COMBUSTION, a REDOX REACTION in which a combustible substance releases energy after it ignites and reacts with the oxygen in the air. • Chemical Fuel • Chemical fuels are substances that release energy by reacting with substances around them, most notably by the process of OXIDATION. • Perhaps the earliest fuel employed by humans is wood. Evidence shows controlled fire was used up to 1.5 million years ago at SOUTH AFRICA. It is unknown which hominid species first used fire, as both Australopithecus and an early species of Homo were present at the sites. As a fuel, wood has remained in use up until the present day, although it has been superseded for many purposes by other sources. Wood has an energy density of 10–20 MJ/kg.
Energy is... • The ability to do work. • Conserved. • made of heat and work. • a state function. • independent of the path, or how you get from point A to B. • Work is a force acting over a distance. • Heat is energy transferred between objects because of temperature difference.
Heat Potential energy
Heat Potential energy
Bomb Calorimeter • thermometer • stirrer • full of water • ignition wire • Steel bomb • sample
Technology • Biomass technology today serves many markets that were developed with fossil fuels and modestly reduces their use • Uses - Industrial process heat and steam, Electrical power generation, Transportation fuels (ethanol and biodiesel) and other products. • Primary focus of the Biomass Program – development of advanced technologies.
Current Focus • Platform technologies • Sugar Platform Technology • Thermochemical Platform Technology
Bio-refinery • A facility that integrates biomass conversion processes and equipment to produce fuels, power, and chemicals from biomass. • Analogous to today's petroleum refineries • It is based on the “Sugar Platform“ and the “Thermochemical Platform“
Bio-diesel • Made by transforming animal fat or vegetable oil with alcohol . • Fuel is made from rapeseed (canola) oil or soybean oil or recycled restaurant grease. • Directly substituted for diesel either as neat fuel or as an oxygenate additive
Modified Waste Vegetable Fat • Designed for general use in most compression ignition engines . • The production of MWVF can be achieved in a continuous flow additive process. • It can be modified in various ways to make a 'greener' form of fuel
E-Diesel • Uses additives in order to allow blending of ethanol with diesel. • Ethanol blends of 7.7% to 15% and up to 5% • Additives that prevent the ethanol and diesel from separating at very low temperatures or if water contamination occurs.
Jatropha • Biodiesel from Jatropha • Seeds of the Jatropha nut is crushed and oil is extracted • The oil is processed and refined to form bio-diesel.
Gasification Technology • Gobar gas Production • Biogas • Synthesis gas
Gasification • A process that uses heat, pressure, and steam to convert materials directly into a gas composed primarily of carbon monoxide and hydrogen. • Gasification technologies rely four key engineering factors 1. Gasification reactor atmosphere (level of oxygen or air content). 2. Reactor design. 3. Internal and external heating. 4. Operating temperature.
Gasification • Typical raw materials - coal, petroleum-based materials, and organic materials. • The feedstock is prepared and fed, in either dry or slurried form, into a sealed reactor chamber called a gasifier. • The feedstock is subjected to high heat, pressure, and either an oxygen-rich or oxygen-starved environment within the gasifier.
Gobar gas • Gobar gas production is an anaerobic process • Fermentation is carried out in an air tight, closed cylindrical concrete tank called a digester
What is a Biodigester? • A device that mimics the natural decay process of organic matter • Biogas is produced from anaerobic decay (decay that occurs without oxygen)
Anaerobic Digestion in a Biodigester • Digester is fed a mixture of water and waste called a slurry • Daily, fresh slurry is added, displacing previous days load that bacteria have started to digest • First, digestible organic matter is broken down by acid-producing bacteria • By-products are then broken down by methane-producing bacteria (journeytoforever.org/biofuel_library/)
Biogas: Green Energy • 50-70% methane; • 30-40% carbon dioxide; • Insignificant amounts of oxygen and hydrogen sulfide (H2S). • Biogas burns without soot or ash being produced • Methane is a combustible gas • Biogas will be used to generate energy for the cooking needs here at Rosalie Forest Eco Lodge (plascoenergygroup)
Digesters Around the World (cont’d) KVIC Digester (used in India and China)
Environmental Concerns • Air Pollution • Soil Deterioration
Air Concerns • Biomass processing technologies and biofuels use have the potential to increase emissions of ozone precursors • Increase in Nox emissions • Excessive inhalation of ethanol is harmful • Combustion of ethanol would result in increased atmospheric concentrations of carcinogens • Emission of relatively large sized particulate matter
Soil Concerns • Burning biomass deprives local eco-systems of nutrients • Production of dedicated energy crops renders land fallow • Reduced land availability for cattle grazing • Increased use of pesticides and fertilizers to produce energy crops contaminate ground and surface water • Affects fish and wildlife
Environmental Benefits • Reduction of waste • Extremely low emission of greenhouse gases compared to fossil fuels • Ethanol is Carbon neutral and forms a part of the carbon cycle • Growing variety of crops increases bio-diversity
Socio-Economic Benefits • Helps developing economies by promoting agrarian communities • Increase in jobs • Increase in trade balance (Indian perspective) due to lesser dependence on foreign resources
BIO FUELS THE WORLD SCENARIO
The Significant Others • China: 3rd largest producer of ethanol producing 220,000 tons of ethanol, exporting 90,000 tons in 2000. • In southeast Asia, the Jatropha tree is used as a significant fuel source • Malaysia and Indonesia are starting pilot-scale production from palm oil.
Sources of ethanol: Sugarcane Molasses Agricultural waste Low average cost of Rs.18/litre projected Annual production capacity of 1.5 Billion litres India
India (Contd.) • Sources of biodiesel: • Honge • Jatropha • High capital, broad scale production plan initiated • Cost per liter projected at Rs. 27
Bio Mass • Biomass already supplies 14 % of the world’s primary energy consumption. On average, biomass produces 38 % of the primary energy in developing countries. • USA: 4% of total energy from bio mass, around 9000 MW • INDIA is short of 15,000 MW of energy and it costs about 25,000 crores annually for the government to import oil.
Bio Mass from cattle manure, agricultural waste, forest residue and municipal waste. • Anaerobic digestion of livestock wastes to give bio gas • Digester consumes roughly one third the power it’s capable of producing. • Fertilizers as by product. • Average electricity generation of 5.5kWh per cow per day!!