Presentation on theme: "Striclty for educational purposes Final project in M.Sc. Course for teachers, in the framework of the Caesarea –Rothschild program of the Feinberg Grad."— Presentation transcript:
Waste to Energy via Syngas (synthetic gas) production and Fischer –Tropsch biodiesel Ben Osher How much diesel can be produced from solid waste in Israel ?
Why Use Waste? As the amount of fossil fuels available decreases and the cost of petroleum- based fuels increases, there is a need for alternative fuel sources. A promising process for green-fuel and electricity production involves the formation of SYNGAS which can be converted to useful fuel and other organic materials.
What is syngas? the main compounds in syngas are: * Carbon monoxide : CO * Hydrogen: H 2 Other by-products: * Carbon dioxide: CO 2 * Methane: CH 4 Abbreviation of “synthetic gas”. It can be the end product of thermally processed biomass
wasteSyngas GREEN DIESEL Gasification Fischer-Tropsch What can be done with syngas?
How much waste is there to be treated? What type of waste is to be treated? For example does it contain just MSW or does it include commercial waste, sewage sludge, tyres etc.? What are the characteristics of the waste in terms of chemical composition, caloric value, particle size, moisture etc.? Dealing with waste - Questions to be asked:
Municipal Solid Waste MSW BIOGENIC NON-BIOGENIC such as food waste and yard clippings such as plastics and metals http://www.eia.gov/todayinenergy/detail.cfm?id=8010
With time the biogenic portion of municipal solid waste decreases; Because non-biogenic waste has a higher heat content than biogenic material the average heat content of MSW (per unit mass) as a whole is increasing, making it a more efficient fuel for producing electricity. Municipal Solid Waste http://www.eia.gov/totalenergy/data/monthly/pdf/historical/msw.pdf
Israel: waste facts 4.9 million ton of MSW is produced each year. Average waste/person/day 1.9 (3-5% growth) ~20% of MSW is recycled => ~ 1.5 kg/day/person to landfills Total fuel consumption for private transportation is http://www.sviva.gov.il/subjectsEnv/Waste/Policy/Documents/waste_management.pdf
Thermal waste treatment Combustion pyrolysis gasification rapid oxidation of a feedstock as it is exposed air. heat in a boiler where steam, under high pressure, is passed through a turbine which powers a generator Thermal degradation of waste in the absence of air to produce char, oil, and syngas. e.g. wood to charcoal Breakdown of hydrocarbons into syngas by controlling the amount of oxygen during burning.
Gasification: Main chemical reactions Within a gasification process the major chemical reactions are those involving carbon, CO, CO 2, water (steam) and methane, as follows: First step: steam Second step: air / Third step:CO formation Endothermic reactions Methane needed comes from Exothermic reactions
Fischer-Tropsch Synthesis It uses Iron- or Cobalt-based catalysts When the H 2 /CO ratio in the feed gas is lower, it can be adjusted with the water gas shift reaction to use the component in excess to yield the missing one: The process involves a series of chemical reactions that produce a variety of saturated hydrocarbons Professor Franz Fischer (left) and Dr Hans Tropsch
MSW conversion and synthesis to F-T products with heat recovery can make beneficial and commercial use of 71%. Overall process: Hypothetical energy recovery
Calculations: Diesel energy density Amount of diesel Av. energy value of MSW Part of MSW for thermal treatment in Israel Amount of diesel produced
A ton of MSW with average energy content of ~5 can yield up to: 323 liters of ultra clean Diesel fuel. FT diesel assumed to be 7.19 $/bbl (~0.16 שקל לליטר ) more expensive than transportation fuels derived from crude oil. Choi & al, 2011 F-T fuels can replace 6% of total fuel consumption in Israel! Conclusions:
Advantages ( if goals are achieved ) Reduction of municipal and industrial waste disposal. Reduction of CO 2 emissions from incineration. Use of renewable low cost feedstocks Converting waste into ultra clean-diesel. Use of sustainable methods to convert waste into useful products
By treating our wastes we do not only do good for the environment but also good business for the local- and global economy.