Ethanol Fuel of the Future

Discussion in 'Earth Science' started by Success_Machine, Sep 2, 2002.

  1. Success_Machine Impossible? I can do that Registered Senior Member

    Is there enough agricultural residue in Canada to support a commercial bioethanol industry?

    There are substantial quantities of straw and other crop residues already produced in Canada. In the Western provinces of Manitoba, Saskatchewan, and Alberta alone, annual production of straw is about 40 million tonnes. If 1/3 of this material was used to make fuel, the nation could replace 10% of its gasoline usage.

    This quote was taken directly from Iogen Corporation website.

    Now consider this: 93 percent of cars on the road have just one person riding in them. One- and two-seat commuter cars would have inherently lighter construction, and if you could reduce the mass of these vehicles by 50 percent you would instantly double their fuel economy. This is a straight & simple law of physics: kinetic energy varies directly with the mass of the object. Interestingly I don't think it would be difficult to reduce the mass of commuter vehicles by 4-fold, from the 3000 pound vehicles on the road today to just 750 pounds, resulting in a 4-fold increase in fuel economy. Theoretically one could reduce the mass of a single-seat vehicle to perhaps 100 kilograms and still retain adequate mobility for a single person, resulting in a 12-fold increase in fuel economy. So I ask you then, could Canada fuel its transportation industry with ethanol?

    To wit:

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    ... And fuel cells have double the energy efficiency of internal combustion engines. Can't wait till they're available. I'm more convinced than ever that I'm on the right track with bioethanol.
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  3. Success_Machine Impossible? I can do that Registered Senior Member

    Refutation of Anti-Ethanol Research by Cornell Scientist

    Here is the research that nearly destroyed consumer confidence in Ethanol as an alternative to petroleum with my comments in braces [ ] ....


    Ethanol fuel from corn faulted as 'unsustainable subsidized food burning' in analysis by Cornell scientist

    FOR RELEASE: Aug. 6, 2001
    Contact: Roger Segelken
    Office: 607-255-9736

    ITHACA, N.Y. -- Neither increases in government subsidies to corn-based ethanol fuel nor hikes in the price of petroleum can overcome what one Cornell University agricultural scientist calls a fundamental input-yield problem: It takes more energy to make ethanol from grain than the combustion of ethanol produces.

    At a time when ethanol-gasoline mixtures (gasohol) are touted as the American answer to fossil fuel shortages by corn producers, food processors and some lawmakers, Cornell's David Pimentel takes a longer range view.

    "Abusing our precious croplands to grow corn for an energy-inefficient process that yields low-grade automobile fuel amounts to unsustainable, subsidized food burning," says the Cornell professor in the College of Agriculture and Life Sciences. Pimentel, who chaired a U.S. Department of Energy panel that investigated the energetics, economics and environmental aspects of ethanol production several years ago, subsequently conducted a detailed analysis of the corn-to-car fuel process. His findings will be published in September, 2001 in the forthcoming Encyclopedia of Physical Sciences and Technology .

    Among his findings are:

    o An acre of U.S. corn yields about 7,110 pounds of corn for processing into 328 gallons of ethanol. But planting, growing and harvesting that much corn requires about 140 gallons of fossil fuels and costs $347 per acre, according to Pimentel's analysis. Thus, even before corn is converted to ethanol, the feedstock costs $1.05 per gallon of ethanol.

    [The same acre of land produces 64,000 pounds of plant fiber, cellulose, hemicellulose, and lignin which can be converted to fermentable sugars to produce far more ethanol than just from corn starch.]

    o The energy economics get worse at the processing plants, where the grain is crushed and fermented. As many as three distillation steps are needed to separate the 8 percent ethanol from the 92 percent water. Additional treatment and energy are required to produce the 99.8 percent pure ethanol for mixing with gasoline. o Adding up the energy costs of corn production and its conversion to ethanol, 131,000 BTUs are needed to make 1 gallon of ethanol. One gallon of ethanol has an energy value of only 77,000 BTU. "Put another way," Pimentel says, "about 70 percent more energy is required to produce ethanol than the energy that actually is in ethanol. Every time you make 1 gallon of ethanol, there is a net energy loss of 54,000 BTU."

    [Ethanol of 180 proof, or 90% ethanol mixed with 10% water, is an excellent automotive fuel. It has slightly lower energy content compared to gasoline, but it will clean your engine of soot and residue from other petroleum-based fuels, and your engine will last 2-3 times longer. However US and Canadian laws say that ethanol must be denatured, or rendered unfit for human consumption to be sold as automotive fuel, or else extra taxes upwards of $22 per liter are applied. Denaturing ethanol is usually accomplished by mixing in 15% gasoline. Distilled ethanol up to 99.8 percent pure is needed if one intends to mix it with gasoline. The water must be removed because while water mixes with ethanol, and ethanol mixes with gasoline, water does not mix with gasoline. Removing the water to achieve such extreme purity by distillation, just so that 15% gasoline can be mixed in, is extremely wasteful of energy. Changing the law to allow non-denatured ethanol to be used as fuel without extra taxes being applied would be the best solution. If not then distillation can be avoided by using hygroscopic materials that absorb water, or by using polyvinyl alcohol membranes that remove water by osmosis, while consuming little or no energy, albeit in a more time consuming manner. ]

    o Ethanol from corn costs about $1.74 per gallon to produce, compared with about 95 cents to produce a gallon of gasoline. "That helps explain why fossil fuels -- not ethanol -- are used to produce ethanol," Pimentel says. "The growers and processors can't afford to burn ethanol to make ethanol. U.S. drivers couldn't afford it, either, if it weren't for government subsidies to artificially lower the price."

    [ Using all the methods available, one can achieve at least a 25% net energy gain. These methods include using cellulose as a feedstock, acid and enzyme hydrolysis to reduce them to sugars, and saving energy on the distillation end by either changing the law, or by using low-energy water separation methods.]

    o Most economic analyses of corn-to-ethanol production overlook the costs of environmental damages, which Pimentel says should add another 23 cents per gallon. "Corn production in the U.S. erodes soil about 12 times faster than the soil can be reformed, and irrigating corn mines groundwater 25 percent faster than the natural recharge rate of ground water. The environmental system in which corn is being produced is being rapidly degraded. Corn should not be considered a renewable resource for ethanol energy production, especially when human food is being converted into ethanol."

    [ Corn should be eaten as food. Non-food crops can be used to produce ethanol, such as grasses, softwood & hardwood lumber residues & sawdust, even recycled cardboard. ]

    o The approximately $1 billion a year in current federal and state subsidies (mainly to large corporations) for ethanol production are not the only costs to consumers, the Cornell scientist observes. Subsidized corn results in higher prices for meat, milk and eggs because about 70 percent of corn grain is fed to livestock and poultry in the United States Increasing ethanol production would further inflate corn prices, Pimentel says, noting: "In addition to paying tax dollars for ethanol subsidies, consumers would be paying significantly higher food prices in the marketplace."

    [There are plenty of alternatives to corn, as noted above.]

    Nickels and dimes aside, some drivers still would rather see their cars fueled by farms in the Midwest than by oil wells in the Middle East, Pimentel acknowledges, so he calculated the amount of corn needed to power an automobile:

    o The average U.S. automobile, traveling 10,000 miles a year on pure ethanol (not a gasoline-ethanol mix) would need about 852 gallons of the corn-based fuel. This would take 11 acres to grow, based on net ethanol production. This is the same amount of cropland required to feed seven Americans.

    o If all the automobiles in the United States were fueled with 100 percent ethanol, a total of about 97 percent of U.S. land area would be needed to grow the corn feedstock. Corn would cover nearly the total land area of the United States.

    [ If cellulose were used widely to produce ethanol, rather than just corn starch, then a 10-fold reduction in the amount of land area needed would be immediately realized. At the same time a diversification of feedstocks would be available, not just corn, but all plant types, whether food crops or non-food grasses and other biomass. Furthermore 93% of cars on the road have only one person riding in them. Reducing the mass of these cars by 7-fold would proportionally increase their fuel economy by the same amount. Taken together these two factors could reduce the land area needed to 1/70th of that estimated by the Cornell scientist.]


    In addition to my own comments, and in a detailed analysis of Pimentel's research, Dr. Michael S. Graboski of the Colorado School of Mines says Pimentel's findings are based on out-of-date statistics and are contradicted by a recent US Department of Agriculture (USDA) study.
    Last edited: Sep 5, 2002
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  5. Success_Machine Impossible? I can do that Registered Senior Member

    The point is Cellulose is used rather than starch

    Corn is the traditionally feedstock for ethanol production. The starch is fermented by yeast in a well-known process. But even corn has less than 10% starch by mass. Almost all plants are composed of up to 98 percent CELLULOSE by mass. In fact cellulose is the most abundant substance produced by living things on earth. Now Iogen Corporation, in Ottawa Canada, has perfected a process to convert cellulose into ethanol. Dubbed "Bioethanol" this will produce ethanol from non-edible parts of plants, and in quantities to supply automotive fuel on a national scale.

    Iogen Corporation has the only demonstration-scale bioethanol plant in the world. From their website we have some idea of the basic process:

    - Steam explosion pre-treatment makes cellulose vulnerable to enzymatic hydrolysis.

    - Either sulfuric acid hydrolysis or enzymatic hydrolysis can be used to convert pre-treated cellulose to fermentable sugars.

    - The sugar is fermented into ethanol using yeast producing an ethanol-water mixture.

    - The ethanol-water mixture is distilled in a fractionating column to produce up to 96% pure ethanol.

    - Vapor phase molecular sieve system is then used to produce anhydrous ethanol up to 99.9% pure.

    - Anhydrous ethanol can then be mixed up with gasoline up to 10% without any modification to the engine or carburator, and is warrentied by all automakers. Coincidentally if this were done on a national scale it would surpass the goals of the Kyoto Protocol to reduce greenhouse gas emissions by 6 percent, simply because bioethanol is a zero net producer of CO2.

    - Waste lignin is produced from hydrolysis, which can be burned as boiler fuel to generate electricity, or to produce heat to aid the distillation process. Alternatively it can undergo gasification, and anaerobic bacteria Clostridium ljungdahlii are used to convert the CO, CO2, and H2 into ethanol in a bioreactor. Other products derived from lignin include livestock feed, soil fertilizer, conductive inks, conductive polymers, biodegradable plastics, high-temperature conductive adhesives, pH & moisture sensors, anti-static coatings for clean-room garments and packaging applications, anti-corrosion coatings, non-linear optical coatings, smart windows, radar-invisible stealth coatings, light-emitting diodes, transistors, electronics, the list goes on...

    - Waste glycerin from the fermentation process can be used as compost fertilizer, livestock feed, boiler fuel, cosmetics, medicinal products, dental products, soap, dynamite, food & beverages, polyether polyols for tobacco industry, alkyd resins, suppository, humectant and emollient, moisturizers, hair care products, toothpaste, sports beverages use glycerol to prevent dehydration, lubricants, epoxy resins, paper, drying foliage with glycerin, fabric softeners, cellophane packaging material, phenol resin cementing compound, nonionic surfactant extracted from glycerin, triglyceride that substitutes for fat in food products, the list goes on...

    Canada to ratify Kyoto before year-end

    The goal was to cut greenhouse gas emissions by 6 percent by 2008-2010. Bioethanol is a zero net producer of greenhouse gases such that converting automotive fuels to E10 (10% ethanol, 90% gasoline) would achieve the goals of Kyoto. And according to the FAQ section of the Iogen website, Canada could replace 10% of gasoline production by using 1/3rd of its supply of wheat straw from the provinces of Alberta, Saskatchewan, and Manitoba. Straw does get used as livestock feed, but Canada has several other provinces that produce straw as well, so I don't think we will have much trouble meeting the Kyoto requirements.
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  7. Success_Machine Impossible? I can do that Registered Senior Member

    My idea: Kelp Forests

    Kelp Forests

    "Kelp forests grow in cold, nutrient rich ocean water, and are one of the most biologically productive habitats in the marine environment."

    My idea:

    Approximately 70% of the surface of the Earth is covered by ocean. Mesh screens suspended 15-40 meters below the surface of the water by floating buoys would provide a surface for root attachments for Kelp Forests over a far larger area than just coastal regions, and in deep water where sunlight cannot reach the seafloor. Kelp can grow 30 cm per day, which can provide a huge feedstock for cellulose-based bioethanol production without using any traditional farmland. Indeed, Kelp forests grow best in cold Canadian waters. Any excess production can be used as fertilizer for land-based food crops, or as food for adjacent fish farms. During storms when kelp forests could be damaged or uprooted, the rafts could be designed to sink deeper where waves on the surface would not affect it. A few hours later when the storm has passed, the raft would again float to the surface. Kelp is great because it has its own floatation sacs, and as the kelp forest grows and gains weight the raft will not require reinforcements to support the growth.

    A skimmer, similar to the equipment that is used to clean up oil spills, could be used to harvest the kelp. As it is pulled aboard it can be drawn through heavy rollers where it is crushed and the water content drained back into the ocean. What is left is dry plant material that can be further processed into bioethanol.

    The USDA Food Nutrient Database provides the following data:

    Seaweed, Kelp, Raw
    (amounts per 100 gram sample)

    Energy = 43 Kcal
    Water = 81.58 g
    Protein = 1.68 g
    Lipids = 0.56 g
    Carbohydrates = 9.57 g
    Fiber = 1.3 g
    Ash = 6.61 g
    Refuse = 0

    Once you squeeze out all the water, you are basically left with dry plant material that is 50% carbohydrates and 7 percent fiber. This is a respectable feedstock for bioethanol - if not from the cellulose, then from the carbohydrate content.
    Last edited: Sep 5, 2002

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