25-03-2011, 09:44 AM
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Technology and Environmental Impact of Biomass & Biofuels
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“
Liquid Fuel Technology
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.
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.
Gaseous fuel Technology
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.
• 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.
Products of gasification :
* Hydrocarbon gases (also called syngas).
* Hydrocarbon liquids (oils).
* Char (carbon black and ash).
• Syngas is primarily carbon monoxide and hydrogen (more than 85 percent by volume) and smaller quantities of carbon dioxide and methane
Gasifier Plant
Types of Gasifiers
• Downdraft Gasifier
• Twin-fire 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
• Solid Fuel
Wood
• Domestic heating with wood is still by far the largest market for bio-energy
• Dramatic improvements of technology in domestic heating equipment
• Improved tiled stoves, advanced logwood boilers, woodchip boilers, pellet boilers and pellet stoves.
• Pourable wood-based fuel is also available