Presentation is loading. Please wait.

Presentation is loading. Please wait.

INTRODUCTION In this century, it is believed that crude oil and petroleum products will become very scarce and costly. Day-to-day, fuel economy of engines.

Similar presentations


Presentation on theme: "INTRODUCTION In this century, it is believed that crude oil and petroleum products will become very scarce and costly. Day-to-day, fuel economy of engines."— Presentation transcript:

1

2 INTRODUCTION In this century, it is believed that crude oil and petroleum products will become very scarce and costly. Day-to-day, fuel economy of engines is getting improved and will continue to improve. However, enormous increase in number of vehicles has started dictating the demand for fuel. With increased use and depletion of fossil fuels, alternative fuel technology will become more common in the coming decades. Because of the high cost of petroleum products, energy security, emission problems some developing countries are trying to use alternate fuels for their vehicles.

3

4

5 Escalating Prices Of Crude Oil

6 Anthropogenic Global Warming History and Future “Neolithic global warming”. Plunge into next ice Age. Normal Interglacial Modern Global Warming Future Global Warming

7 Why is Global Warming Bad? The fast rise in temperature may trigger the next major ice sooner than it would otherwise occur, due to switching off. The fast rise in temperature may trigger the next major ice sooner than it would otherwise occur, due to switching off Atlantic Ocean currents. Rapid changes in temperature cause agriculture possibilities to switch from one area of the world to another. Thus, many people will die due to lack of food. Rapid changes in temperature cause agriculture possibilities to switch from one area of the world to another. Thus, many people will die due to lack of food. Rapid increases in temperature cause more severe weather to occur, such as hurricanes. Thus, many people will die (have already died!). Rapid increases in temperature cause more severe weather to occur, such as hurricanes. Thus, many people will die (have already died!). Rapid increases in temperature cause the glacial ice at the North and South Poles to melt, raising sea levels; which will flood many major cities of the world. Rapid increases in temperature cause the glacial ice at the North and South Poles to melt, raising sea levels; which will flood many major cities of the world. Neolithic Global Warming Modern Global Warming Future Global Warming Plunge into ice Age.

8 LIQUID FUELS: Liquid fuels are preferred for IC engines because they are easy to store and have reasonably good calorific value. The main alternative is the alcohol ALCOHOL: Alcohols are attractive alternate fuels because they can be obtained from both natural and manufactured sources. Methanol and ethanol are two kinds of alcohols that seem most promising.

9 Closed carbon dioxide greenhouse gas cycle for biofuels. Ethanol & biodiesel are sustainable forms of solar energy. What about Using Ethanol and/or Biodiesel for Fuel? Farmers must use biofuels to produce biofuels, not petro fuels!

10 Structure of ethanol molecule. All bonds are single bonds Glucose (a simple sugar) is created in the plant by photosynthesis. 6 CO 2 + 6 H 2 O + light → C 6 H 12 O 6 + 6 O 2 CH 3 CH 2 OH During ethanol fermentation, glucose is decomposed into ethanol and carbon dioxide. C 6 H 12 O 6 → 2 CH 3 CH 2 OH+ 2 CO 2 + heat During combustion ethanol reacts with oxygen to produce carbon dioxide, water, and heat: CH 3 CH 2 OH + 3 O 2 → 2 CO 2 + 3 H 2 O + heat

11 HOW IS IT MADE NOW?  HISTORICALLY MADE FROM CORN AND OTHER STARCH SOURCES OR FROM NATURAL SUGARS BY FERMENTATION  COMMON SOURCES INCLUDE RICE, POTATO, CASSAVA – PLUS CORN AND OTHER GRAINS  MANUFACTURING PROCESS WAS VERY ENERGY- INTENSIVE, BUT IS NOW LESS SO IN MOST MODERN PLANTS, DUE TO ADVANCES IN DISTILLATION TECHNOLOGY Ethanol

12

13

14

15

16

17 DRY MILL CORN ENZYMATIC HYDROLYSER STARCH FERMENTER CORN SYRUP co 2 STILL HEAT DEHYDRATOR ‘DRY’ FUEL ETHANOL PRODUCT

18 800-597-9747 www.iqlearningsystems.com Michael Wang – Argonne National Laboratory, Aug. 2005 Energy Input ratio = input for EtOH / input for gasoline =.74/1.23 = 0.6 : 1

19 Some Properties of Methanol, Gasoline and Diesel Fuel

20 Summary of mass balance Out of 87730kg. Of sugar beet Plants we get 3775kg.(4775 l) Of EtOH 38990kg. Of tops & leaves 2760kg of beet pulp 1220kg. Of undecanted stillage Remaining water by subtraction Mass and Energy Balance

21

22 THE FARMING OPERATION TAKES ALL ANTHROPOMORPHIC AND NATURAL ENERGY INPUTS AND CONVERTS THEM INTO ENERGY CONTAINED IN A CROP. THIS CROP MAY BE BIOMASS OF ALMOST ANY KIND OR, MORE NARROWLY, MAY BE CORN, AN OILSEED CROP SUCH AS SOYBEAN OR RAPESEED OR A FOOD CROP PLUS A CROP RESIDUE USED FOR CONVERSION INTO ENERGY FUEL FOR FARM OPERATIONS (VERY SMALL) FERTILIZER (VERY SMALL) NATURAL ENERGY INPUTS (VERY LARGE) FARM PRODUCT(S) (ADD: TRANSPORTATION AND HANDLING ENERGY) THE ENERGY CONVERSION OPERATION EXTRACTS COMPONENTS HAVING AN ENERGY VALUE FROM THE CROP BY PHYSICAL, CHEMICAL AND/OR BIOCHEMICAL PROCESSING. THE REQUIRED PROCESS ENERGY INPUTS MAY BE DERIVED DIRECTLY OR INDIRECTLY FROM THE FARM PRODUCTS OR BY BURNING FOSSIL FUELS. BY-PRODUCTS MAY OR MAY NOT BE INCLUDED IN THE ENERGY BALANCE DEPENDING ON THEIR USE. NON-ENERGY BYPRODUCTS (QUANTIFY BUT EXCLUDE): E.G., UNUSED WASTE, ANIMAL FOOD NET ENERGY PRODUCT PROCESS HEAT (TYPICALLY FOSSIL FUEL) ELECTRICAL POWER FOR PUMPS, ETC. ADD: TRANSPORTATION, BLENDING AND DISTRIBUTION, ENERGY USE FARM PRODUCT(S) : TREAT AS FEEDSTOCK FOR CONVERSION PROCESS OTHER INPUTS AS RELEVANT: CHEMICALS WATER STEAM FARM ▲ REFINERY

23 Energy received from sunlight [(i) Energy content of sugar beet] [(ii) By products,tops & leaves 245.7 167.2 78.5 Energy invested at farm31.3 Energy invested in building EtOH plant2.4 So, total energy invested33.7 By products, tops & leaves left at farm{as fertilizers }11.0 NET INVESTED ENERGY AT FARM22.7 ENERGY OBTAINED FROM EtOH101.8 FROM By-products Bio-Gas14.7 FROM Beet Pulp32.3 FROM Stillage18.7 Energy invested at Industry in producing EtOH {Let this energy be equivalent to energy received from by products} 64.1 SO,NET ENERGY OBTAINED = [101.8 – 22.7] GJ/ha = 79.1 (GJ/ha) Energy balance calculation

24 Energy Balances of biomass Fuels

25 BIOMASS TO ETHANOL AN INTEGRATED, FULL-SCALE COMMERCIAL BIOPROCESS PLANT CONSISTS OF FIVE BASIC UNIT OPERATIONS 1. FEEDSTOCK PREPARATION; 2. DECRYSTALLIZATION/HYDROLYSIS REACTION VESSEL; 3. SOLIDS/LIQUID FILTRATION; 4. SEPARATION OF THE ACID AND SUGARS; 5. FERMENTATION OF THE SUGARS; AND, 6. PRODUCT PURIFICATION.

26 BIOMASS TO ETHANOL (1) ABENGOA (AND OTHERS)

27

28 BIOMASS TO ETHANOL ABENGOA PROPOSED PLANT IN KANSAS www.abengoabioenergy.com/research/index.cfm?page=7 RAW MATERIAL INPUT: 700 TONS/DAY (210,000 TONS/YR*) CORN STOVER, WHEAT STRAW, MILO STUBBLE, SWITCHGRASS, ETC. PLANT WILL PRODUCE: 11.4 MILLION GALLONS OF ETOH/YR ENOUGH ENERGY TO POWER THE FACILITY EXCESS ENERGY WILL BE USED TO POWER ADJACENT CORN DRY GRIND MILL

29 BIOMASS TO ETHANOL (2) ALICO/BRI (COSKATA IS SIMILAR)

30 PROPOSED PLANT IN LABELLE, FLORIDA www.brienergy.com/pages/process01.html RAW MATERIAL INPUT: 770 TONS/DAY (231,000 TONS/YR*) YARD, WOOD, & VEGETATIVE WASTES PLANT WILL PRODUCE (ASSUMING 24 HR/DAY, 300 DAY/YR): 13.9 MILLION GALLONS OF ETOH/YR 6,255 KW OF ELECTRIC POWER (~45 GWH/YR*) 8.8 TONS H 2 /DAY (2,640 TONS H 2 /YR*) 50 TONS AMMONIA/DAY (15,000 TONS AMMONIA/YR* )

31 Conversion of Cellulose/Hemicellulose to Mixed Sugars Using Patented Arkenol Process Technology of Concentrated Acid Hydrolysis Simplified Flow Diagram Steam Lignin Filter 1st stage Hydrolysis 2nd stage Hydrolysis Concentrated Acid Reconcentration Acid/Sugar Biomass Sulfuric Acid Purified Lime Centrifuge Mixing Tank Gypsum Mixed Sugars to Fermentation or Direct conversion - Hydrogenation - Thermal conversion Chromatographic Separation Acid Recovery Solids Water Condensate Return Sulfuric Acid Solution Steam Strong Sugar Solution Solids Pump Liquor to silica processing (as required) A 10-Step Overview 10 6 7 5 4 3 2 1 8 9 http://www.luefireethanol.com/

32 BlueFire Ethanol, Inc. PROPOSED PLANT IN SOUTHERN CALIFORNIA RAW MATERIAL INPUT: 700 TONS/DAY (210,000 TONS/YR*) OF SORTED GREEN WASTE AND WOOD WASTE FROM LANDFILLS PLANT WILL PRODUCE: 19 MILLION GALLONS OF ETOH/YR TECHNOLOGY: ARKENOL CONCLUDED THAT CONCENTRATED ACID HYDROLYSIS WAS THE ONLY PROCESS ECONOMICALLY VIABLE AND CAPABLE OF PROCESSING ANY CELLULOSE WASTES ARKENOL AND AFFILIATES HAVE MUCH EXPERIENCE *based on a 300 day year

33 Cellulosic

34 BROIN COMPANIES PROPOSED PLANT IN EMMETSBURG (PALO ALTO COUNTY), IOWA RAW MATERIAL INPUT: 842 TONS/DAY (252,600 TONS/YR*) OF CORN FIBER, COBS AND STALKS PLANT WILL PRODUCE: 125 MILLION GALLONS OF ETOH/YR (25% OF THEM ARE CELLULOSIC ETHANOL) TECHNOLOGY: BROIN FRACTIONATION, ALSO TRADEMARKED BFRAC™. *based on a 300 day year

35 BFRAC™ THIS NEW BIO-REFINING TECHNOLOGY SEPARATES THE CORN INTO THREE FRACTIONS INCLUDING FIBER, GERM AND ENDOSPERM. THE ENDOSPERM IS THEN FERMENTED TO CREATE ETHANOL, WHILE THE REMAINING FRACTIONS ARE CONVERTED INTO NEW VALUE-ADDED CO-PRODUCTS, INCLUDING DAKOTA GOLD HP™, DAKOTA BRAN™ CAKE, CORN GERM MEAL, AND CORN OIL. IN ADDITION TO THESE HIGH VALUE CO- PRODUCTS, THE PROCESS ALSO RESULTS IN INCREASED ETHANOL YIELDS AND DECREASED ENERGY CONSUMPTION.

36

37

38 IOGEN BIOREFINERY PARTNERS, LLC PROPOSED PLANT IN SHELLEY, IDAHO RAW MATERIAL INPUT: 700 TONS/DAY (210,000 TONS/YR) AGRICULTURAL RESIDUES INCLUDING WHEAT STRAW, BARLEY STRAW, CORN STOVER, SWITCHGRASS, AND RICE STRAW AS FEEDSTOCKS PLANT WILL PRODUCE: 18 MILLION GALLONS OF ETOH/YR TECHNOLOGY - TRADITIONAL ENZYME FERMENTATION PRODUCTION [1]Iogen Corp, “CELLULOSE ETHANOL: Clean Fuel for Today and Tomorrow” [2]http://www.tc.gc.ca/programs/Environment/climatechange/docs/biomass /Image4.gif [3] Iogen Ethanol process: http://www.gmcanada.com/inm/gmcanada/english/about/MissionGreen/Da ily/Sep20.html *based on a 300 day year

39 IOGEN’S PATENTED ETHANOL PROCESS [1] [2] #1 #5 #3 #7 #6 #4 #2 #8 #1#3 #7#6 #4#2 #8#5 Block Diagram of 8 stage Process [2] Products of 8 stage Process [2] Block Diagram of 8 stage Process [1] Assuming 320 of EtOH L/dry ton Yields approximately 17.75 Mgal EtOH

40 RANGE FUEL’S PATENTED ETHANOL PROCESS PROXIMITY TO BIOMASS FEEDSTOCK AND ETHANOL MARKETS RAIL AND ROAD ACCESS WATER, POWER, GAS, AND SEWER AVAILABILITY. OPTIMAL FEEDSTOCK DRAW ( 45MI AND 75 MI RADII) [1] “Vinod Khosla,”Mostly convenient truths”

41 RANGE FUELS PROPOSED PLANT IN SOPERTON, GEORGIA RAW MATERIAL INPUT: 1200 TONS/DAY (360,000 TONS/YR*) WOOD RESIDUES AND WOOD BASED ENERGY CROPS. PLANT WILL PRODUCE: 40 MILLION GALLONS OF ETHANOL/YEAR 9 MILLION GALLONS OF METHANOL/YEAR TECHNOLOGY THERMO-CHEMICAL CONVERSION PROCESS (THE “K2 SYSTEM”) CONVERT BIOMASS TO A SYNTHETIC GAS CONVERT THE GAS TO ETHANOL. *based on a 300 day year

42 RANGE FUEL’S PATENTED ETHANOL PROCESS - RATIONALE FERMENTATION AND ACID HYDROLYSIS CAN TAKE DAYS TO OCCUR, BUT THERMAL CONVERSION BREAKS DOWN ORGANIC MATTER AND CONVERTS IT TO ETHANOL IN MINUTES. THE PROCESS USES LITTLE ENERGY TO START; IT FUELS ITSELF IN A SELF-SUSTAINING FASHION; IT PRODUCES VIRTUALLY NO WASTE PRODUCTS; IT EMITS VERY LOW LEVELS OF GREENHOUSE GAS. RANGE FUELS CLAIMS IT CAN PRODUCE MORE ETHANOL FOR A GIVEN AMOUNT OF ENERGY EXPENDED THAN IS POSSIBLE WITH ANY OTHER COMPETING PROCESS. DEPENDING UPON THE QUANTITY AND AVAILABILITY OF FEEDSTOCK, THE K2 SYSTEM CAN SCALE FROM ENTRY-LEVEL SYSTEMS TO LARGE CONFIGURATIONS. THIS RANGE OF SYSTEM PERFORMANCE WILL ALLOW THE K2 TO BE PLACED NEAR THE BIOMASS LOCATION REDUCING TRANSPORTATION COSTS, AND WILL ALLOW THE MOST ECONOMICAL SIZE SYSTEM TO BE DEPLOYED. SINCE THE SYSTEM IS MODULAR, ADDING ANOTHER MODULE – WHICH IS EASY TO SHIP AND INSTALL, INCREASES THE OUTPUT. [1] “Another Cellulosic Ethanol Plant Announced “, http://thefraserdomain.typepad.com/energy/2007/02/another_cellulo.html

43 Properties of Ethanol, Methanol, Gasoline and Diesel Fuel

44 Blending 1 ] Automobile fuels be “oxygenated” in order to reduce air pollution. Since alcohols contain oxygen, interest in ethanol as an oxygenate. 2]In addition, removal of lead from gasoline renewed interest in ethanol as octane booster. There are alternatives to ethanol for both of these needs. The oil industry originally pushed MTBE as an oxygenate, but it was phased out after discovery that it was causing water pollution problems. 3] While E10/E15 is intended for all automobiles, a blend called “E85” is intended for flex fuel vehicles. E85 is nominally 85% ethanol and 15% gasoline, albeit it can be as high as 30% gasoline in cold climates in winter. The principle reason for blending some gasoline into ethanol for flex fuel vehicles is to improve starting in cold weather.

45 4] above, ethanol is separated from the water in which it is produced via a process called distillation. The distillation process does not remove all of the water. Having some water mixed in with the fuel is actually improves performance of an internal combustion engine, as the water provides extra mass to absorb the heat of combustion and turn it into high pressure steam for mechanical energy. 5] ethanol as low as 160 proof (80% ethanol, 20% water) works very well in automobile engines designed to run on alcohol. 6] However, water and gasoline don’t mix well (are not “miscible”, in chemical terms), so the water must be removed when producing ethanol-gasoline blends. This dry or “anhydrous” ethanol is needed to prevent phase separation of the fuel components in ethanol - gasoline blends.

46 Power Making Fuel Characteristics 1. Octane Rating 2. Burning Rate 3. Latent Heat of Vaporization 4. Energy Value 800-597-9747 www.iqlearningsystems.com 1.Octane Rating [ MON ] 2.Burning Rate 3.Latent Heat of Vaporization [ kJ/kg ] 4.Energy Value [ MJ/kg ] & 5.Reduction in Green house gases

47 1. Octane Measures fuel’s resistance to pre- ignition and detonation, commonly called “knocking” Three common octane ratings for motor fuels:  Research Octane Number (RON)  Motor Octane Number (MON)  (R+M/2) method 800-597-9747 www.iqlearningsystems.com

48 1. Octane ( cotd.) MON rating is most useful to racers because it is measured under high loads and at high RPM’s High MON rated fuels allow the use of higher compression and advanced spark timing E85 delivers MON octane ratings equal to, or better than, most gasoline 800-597-9747 www.iqlearningsystems.com

49 2. Burning Rate The speed at which fuel burns and releases its heat energy There is less time for fuel to burn at high RPM’s, so rapid burning fuel is a must in racing Peak horsepower (kW) and engine efficiency are realized if fuel is almost completely burned by 20 degrees after Top Dead Center (TDC) 800-597-9747 www.iqlearningsystems.com

50 3. Latent Heat of Vaporization Measures a fuel’s ability to cool the intake charge and combustion chamber Measured in kJ/ lt. Higher rated fuels remove heat better 800-597-9747 www.iqlearningsystems.com

51 3. Latent Heat of Vaporization E85 promotes better cooling: Making the intake charge more dense, thereby packing more energy (per volume) into the engine Helping to control detonation Reducing temperatures in the engine and oiling system components 800-597-9747 www.iqlearningsystems.com

52 4. Energy Value The total heat energy contained in a given amount of fuel – kJ/kg Horsepower generation depends on “Net Energy Value” - Equal to the energy value multiplied by the amount of fuel that can be burned A fuel’s “stoichiometric” defines its ideal air/fuel ratio Lower stoichiometric fuels allow more fuel to be burned which, in turn, increases the Net Energy Value of the fuel 800-597-9747 www.iqlearningsystems.com

53 A fuel’s “stoichiometric” defines its ideal air/fuel ratio Lower stoichiometric fuels allow more fuel to be burned which, in turn, increases the Net Energy Value of the fuel The lower stoichiometric of E85 provides the fuel with a higher Net Energy Value than most gasoline

54 800-597-9747 www.iqlearningsystems.com “Ethanol Blends Significantly Reduce Greenhouse Gas Emissions” Argonne National Labs. Reduction in GHG

55 Fuel Comparison Chart 800-597-9747 www.iqlearningsystems.com Fuel Octane (MON) Burning Rate (ms@stoic.) Latent Heat (BTU/gal) Energy Value BTU/lbs Power Stoic. Net Energy Value (MJ/kg) Pure Ethanol 102.3939612,8006.5/13.00 Pure Methanol 103.435039,7505/13.08 Pump Gasoline 80-90.34 150 (avg.) 18,700- 19,100 12.5/12.92 Racing Gasoline 99N/A 160 (est.) 18,500 (est.) 12.5/12.90 E3087-94.3633717,17810.7/12.94 E8599-100.3835914,0217.4/12.99

56 Fuel Rankings 800-597-9747 www.iqlearningsystems.com Fuel Octane (MON) Burning Rate (ms@stoic.) Latent Heat (BTU/gal) Net Energy Value (MJ/kg) Pure Ethanol 2522 Pure Methanol 1611 Pump Gasoline 6265 Racing Gasoline 4156 E305344 E853433

57 DIFFICULTIES: 1. Extensive research and development is difficult to justify until the fuels are accepted as viable for large numbers of engines. 2. Most alternate fuels are very costly at present since the quantity used is very less. 3. There is lack of distribution points (service stations) where fuel is available to the public.

58 BRAZIL World leader in production and export of ethanol. Ethanol produced per day equivalent to 200,000 barrels of gasoline. 24% blend ethanol mandatory. Competitiveness Bio diesel initiatives underway U.S.A. Ethanol : a big boost to economy E85 sells cheaper than gasoline Currently production aimed at 4.5 Billion gallons/yr India Sources of ethanol: Sugarcane Molasses Agricultural waste Low average cost of Rs.18/litre projected Annual production capacity of 1.5 Billion litres

59 Alcohol fuel conversion apparatus for internal combustion engines Alcohol fuel conversion apparatus for internal combustion engines including a fuel tank, a fuel pump, a primary heat exchanger, a heat source, a converter and a carburetor. The pump delivers pressurized liquid alcohol to the primary heat exchanger where the alcohol fuel is heated above the vaporization point at ambient pressure. The heated fuel is next delivered to the converter where the super-heated liquid alcohol is vaporized at reduced pressure. The alcohol is then delivered to the carburetor where the vaporized alcohol is metered and mixed with air for proper combustion. The air-fuel mixture, in gaseous form is then delivered to the intake system of a conventional internal combustion engine. A fuel pre-heater assembly utilizing waste heat from the engine may also be provided.

60 ADVANTAGES: 1. It is a high octane fuel with anti-knock index numbers of over 100.Engines using high octane fuel can run more efficiently by using higher compression ratios. Alcohols have higher flame speed. 2. It produces less overall emissions compared to gasoline. 3. When alcohols are burned, it forms more moles of exhaust gases, which gives higher pressure and more power in the expansion stroke. 4. It has high latent heat of vaporization which results in a cooler intake process. This raises the volumetric efficiency of the engine and reduces the required work input in the compression stroke. 5. Alcohols have low sulphur content in the fuel. 6. Reduced petroleum imports and transportation.

61 DISADVANTAGES: 1. Alcohols have low energy content or in other words the calorific value of the fuel is almost half. This means that almost twice as much as gasoline must be burned to give the same energy input to the engine. With equal thermal efficiency and similar engine output usage, twice as much fuel would have to be purchased, and he distance which could be driven with a given fuel tank volume would be cut in half. Automobiles as well as distribution stations would require twice as much storage capacity, twice the number of storage facilities, twice the volume of storage at the service stations, twice as many tank trucks and pipelines, etc. Even with the low energy content of the fuel, engine power for a given displacement would be about the same. This is because of the lower air- fuel ratio needed by alcohol. Alcohol contains oxygen and thus requires less air for stoichiometric combustion. More fuel can be burned with the same amount of air. 2. Combustion of alcohols produces more aldehydes in the exhaust. If as much alcohol fuel was consumed as gasoline. Aldehyde emissions would be a serious problem.

62 3. Alcohol is much more corrosive than gasoline on copper, brass, aluminum, rubber, and many plastics. This puts some restrictions on the design and manufacturing of engines to be used with this fuel. Fuel lines and tanks, gaskets, and even metal engine parts can deteriorate with long-term alcohol use (resulting in cracked fuel lines, the need for special fuel tank, etc). Methanol is very corrosive on metals. 4. It has poor cold weather starting characteristics due to low vapor pressure and evaporation. Alcohol-fuelled engines generally have difficulty in starting at temperatures below 10 C. Often a small amount of gasoline is added to alcohol fuel, which greatly improves cold-weather starting. However, the need to do this greatly reduces the attractiveness of alcohol. 5. Alcohols have poor ignition characteristics n general.

63 6. Alcohols have an almost invisible flame, which is considered dangerous when handling fuel. A small amount of gasoline removes this danger. 7. There is the danger of storage tank flammability, due to low vapor pressure. Air can leak into storage tanks and create combustible mixtures. 8. There will be less NOx emissions because of low flame temperatures. However, the resulting lower exhaust temperatures take longer time to heat the catalytic converter to efficient operating temperatures. 9. Many people find the strong odor of alcohol very offensive. Headaches and drizzles have been experienced when refueling an automobile. 10. There is a possibility of vapor lock in fuel delivery systems

64 METHANOL: Of all the fuels being considered as an alternate to gasoline, methanol is one of the most promising and has experienced major research and development. Pure methanol and mixtures of methanol and gasoline in various percentages have been extensively tested in engines and vehicles for a number of years. The most common mixtures are M85 (85% methanol and 15% gasoline). The data of these tests which include performance and emission level levels are compared with pure gasoline (M0) and pure methanol (M100). Some smart flexible fuel (or variable fuel) engines are capable of using any random mixture combination of methanol and gasoline ranging from methanol to pure gasoline. Two fuel tanks are used and various flow rates of the two fuels can be pumped to the engine, passing through a mixing chamber. Using information from sensors in the intake and exhaust, the electronic monitoring systems (EMS) adjust to the proper air-fuel ratio, ignition ratio, ignition timing, injection timing, and valve timing (where possible) for the fuel mixture being used.

65 Methanol can be obtained from many sources, both fossil and renewable. These include coal, petroleum, natural gas, biomass, wood, landfills, and even the ocean. However, any source that requires extensive manufacturing or processing raises the price of the fuel. Emissions from an engine using M10 fuel are about the same as those using gasoline. The advantage (and disadvantage) of using this fuel is mainly 10% decrease in HC and CO exhaust emissions. However, there is an increase in NOx and a large (500%) increase in formaldehyde emissions. Methanol is used some dual-fuel CI engines. Methanol by itself is not a good CI engine fuel because of its high octane number, but if a small amount of diesel oil is used for ignition, it can be used with good results. This is very attractive for developing countries, because methanol can often be obtained from much cheaper source than diesel oil. Methanol fuel has received less attention than ethanol fuel as an alternative to petroleum based fuels.

66 Use Methanol fuel is also used extensively in drag racing, primarily in the Top Alcohol category. Formula One racing continues to use gasoline as its fuel, but in pre war grand prix racing methanol was often used in the fuel. Use as internal combustion engine fuel Both methanol and ethanol burn at lower temperatures than gasoline, and both are less volatile, making engine starting in cold weather more difficult. Using methanol as a fuel in spark ignition engines can offer an increased thermal efficiency and increased power output (as compared to gasoline) due to its high octane rating (114) and high heat of vaporisation. However, its low energy content of 19.7 MJ/kg and stoichiometric air fuel ratio of 6.42:1 mean that fuel consumption (on volume or mass basis) will be higher than hydrocarbon fuels. The extra water produced also makes the charge rather wet (similar to hydrogen/oxygen combustion engines)and combined with the formation of acidic products during combustion, the wearing of valves, valve seats and cylinder might be higher than with hydrocarbon burning. Certain additives may be added to motor oil in order to neutralize these acids.

67 Methanol, just like ethanol, contains soluble and insoluble contaminants. These soluble contaminants, halide ions such as chloride ions, have a large effect on the corrosivity of alcohol fuels. Halide ions increase corrosion in two ways; they chemically attack passivating oxide films on several metals causing pitting corrosion, and they increase the conductivity of the fuel. Increased electrical conductivity promotes electric, galvanic, and ordinary corrosion in the fuel system. Soluble contaminants, such as aluminium hydroxide, itself a product of corrosion by halide ions, clog the fuel system over time. Methanol is hygroscopic, meaning it will absorb water vapor directly from the atmosphere. Because absorbed water dilutes the fuel value of the methanol (although, it suppresses engine knock), and may cause phase separation of methanol-gasoline blends, containers of methanol fuels must be kept tightly sealed.

68 Toxicity Methanol is poisonous; ingestion of only 10 ml can cause blindness and 60-100 ml can be fatal, and it doesn't have to be swallowed to be dangerous since the liquid can be absorbed through the skin, and the vapors through the lungs. US maximum allowed exposure in air (40 h/week) is 1900 mg/m³ for ethanol, 900 mg/m³ for gasoline, and 1260 mg/m³ for methanol. However, it is less volatile than gasoline, and therefore decreases evaporative emissions. Use of methanol, like ethanol, significantly reduces the emissions of certain hydrocarbon-related toxins such as benzene and 1, 3 butadiene. But as gasoline and ethanol are already quite toxic, safety protocol is the same.

69 Safety Since methanol vapour is heavier than air, it will linger close to the ground or in a pit unless there is good ventilation, and if the concentration of methanol is above 6.7% in air it can be lit by a spark, and will explode above 54 F / 12 C. Once ablaze, the flames give out very little light making it very hard to see the fire or even estimate its size, especially in bright daylight. If you are unlucky enough to be exposed to the poisonous substance through your respiratory system, its pungent odor should give you some warning of its presence. However, it is difficult to smell methanol in the air at less than 2,000 ppm (0.2%), and it can be dangerous even at lower concentrations

70 E85,alcohol fuel mixture of 85% ethanol and 15% gasoline E85 is an alcohol fuel mixture of 85% ethanol and 15% gasoline, by volume. ethanol derived from crops (bioethanol) is a biofuel. E85 as a fuel is widely used in Sweden and is becoming increasingly common in the United States, mainly in the Midwest where corn is a major crop and is the primary source material for ethanol fuel production. E85 is usually used in engines modified to accept higher concentrations of ethanol. Such flexible-fuel engines are designed to run on any mixture of gasoline or ethanol with up to 85% ethanol by volume. The primary differences from non-FFVs is the elimination of bare magnesium, aluminum, and rubber parts in the fuel system, the use of fuel pumps capable of operating with electrically-conductive (ethanol) instead of non-conducting dielectric (gasoline) fuel, specially-coated wear-resistant engine parts, fuel injection control systems having a wider range of pulse widths (for injecting approximately 30% more fuel), the selection of stainless steel fuel lines (sometimes lined with plastic), the selection of stainless steel fuel tanks in place of terne fuel tanks, and, in some cases, the use of acid-neutralizing motor oil. For vehicles with fuel-tank mounted fuel pumps, additional differences to prevent arcing, as well as flame arrestors positioned in the tank's fill pipe, are also sometimes used..

71 Ethanol and Flexible Fuel Vehicles (FFVs) What is a FFV? FFVs are specially designed to run on all ethanol blends up to 85% FFVs can use any mixture of gasoline or E85 FFVs observe a mileage reduction on E85 vs. gasoline FFVs have fuel sensors which monitor ethanol/gasoline ratios All Gasoline All E85 % Mixture

72 Ethanol & E85 vs. Gasoline

73 Fuel Properties Ethanol vs. Gasoline

74 ASTM D5798-99 Standard Specification for Fuel Ethanol (Ed75Ed85) For Automotive Spark-Ignition Engines

75

76 Electronic Fuel Injection System

77

78 The Fuel Delivery System

79

80 The Air Induction System

81

82 The Electronic Control System

83

84

85

86

87

88

89

90

91

92

93 The stoichiometric ratio for gasoline is around 14.7:1 (note: since gasoline is a mixture of different hydrocarbon molecules, the stoichiometric ratio is only approximate. The stoichiometric ratio for pure ethanol is approximately 9:1 and for E85, it is about 9.8:1. The reason for this difference in stoichiometric ratio is because ethanol is an oxygenated fuel An engine that is supplied with more fuel than is required by the stoichiometric ratio is said to be running rich. Conversely, an engine that is supplied with more air than is required by the stoichiometric ratio is said to be running lean. An overly rich mixture will not burn all of the fuel and will therefore be inefficient. It will lose power and have poor fuel economy, as well as produce an excess of the pollutants carbon monoxide (CO) and unburned hydrocarbons (particulates). A rich mixture will tend to make the engine run cool for two reasons: (1) not all of the fuel is burned, and (2) the excess liquid fuel will absorb heat from the cylinder in the process of evaporation. Electronically Controlled Fuel Injection

94 Leaning the mixture will generally cause the engine to heat up excessively near the stoichiometric ratio and then the power will fall off, engine efficiency will drop, and the engine will cool down as the mixture is leaned out further. Less mass in the fuel means less mass in the exhaust gasses that create mechanical energy by expanding when absorbing combustion heat. Automobile manufacturers try to achieve high fuel efficiency standards while simultaneously keeping exhaust pollution low. Furthermore, the manufacturers are required to warrant pollution control limits for the life of the vehicle. Today the life is 150,000 miles or more. In order to meet all of these requirements as the engine components wear with age and use, the automobile manufacturers have decided that the engine cannot have fixed settings but must adjust to conditions and wear dynamically. Therefore, since the 1980s, all new cars have been fitted with electronically controlled fuel injection (EFI) systems. The engine control computer, ECU, provides the necessary signals at the correct times. The ECU receives signals about the ( i) operator’s intentions (throttle position), (ii) the engine’s needs (manifold absolute pressure), (iii) engine speed and position, (iv) engine temperature, (v) air mass pulled into the engine (compensating for altitude and ambient air pressure) through various sensors. The ECU uses these sensors to determine the precise timing of the pulsing of each fuel injector. The ECU computes the desired air/fuel ratio at each moment in time from the sensors mentioned above, and then computes the precise time to open the injectors to provide the necessary amount of fuel to the engine.

95 In order to compensate for engine component wear, changes in fuel composition, and other variable factors, modern EFI engines contain one or more heated oxygen sensors (HO2 sensors) in the exhaust system, just outside the engine. In spite of the common name, these sensors don’t actually sense oxygen; they sense a factor called lambda which is the deviation (rich or lean) from stoichiometric ratio, as determined by the composition of the engine exhaust gasses. The highlighted text is very important in this discussion. The HO2 sensor determines the actual fuel mixture that was just burned in the engine in real-time, regardless of the type of fuel or the actual value of its stoichiometric ratio! This operation is key to understanding how a gasoline powered EFI engine responds to the presence of an alternative fuel, such as ethanol, with a different stoichiometric ratio.

96 Ignition Timing. In order to achieve optimum engine performance, the pressure wave from the exploding fuel’s exhaust gasses must hit top of the piston at the time when the piston is just a little past the top dead center of its travel. This causes the maximum pressure to build up on the piston because the cylinder volume is at its smallest. If the spark ignites the fuel too late, the piston will have been pulled down somewhat in the cylinder and the power stoke will operate off of less compression, reducing the power delivered to the engine from that power stoke. Conversely, if the spark ignites the fuel prior to the piston coming past top dead center of its travel, the pressure wave may press down on the piston while it is still being driven up in the compression stroke, causing severe power loss, as the fuel ignition now works against the engine for a short while in lieu of providing power to it. This latter condition is known as pre-ignition or “engine knock” and may damage the engine if it persists.

97 All modern EFI engines have a sensor that informs the ECU of the position of crankshaft or camshaft rotation dynamically, while the engine runs. The ECU’s software uses tables (sometimes referred to as engine control “maps”) to determine the correct timing of firing the spark plug, as well as the desired air/fuel ratio, given the instantaneous needs of the engine and its mode of operation Note that it takes a short but finite time for the spark plug to ignite the air/fuel mixture in the cylinder and for the resulting pressure wave to hit the top of the piston. Thus, the spark must fire sometime before the piston is in the optimum position. Modern automobile engines differ somewhat in how the ignition timing is controlled. Some engines just use data computed by the ECU from the map and from the engine position and speed sensors. Other engines actually have “knock sensors” that detect engine knocking and inform the ECU. These knock sensors, or similar sensors, allow the ECU to determine the precise ignition firing time dynamically, achieving superior performance when compared to a fixed setting in the map based only upon the engine design. Otherwise, ignition timing is programmed to be a little later (retarded) than optimal to ensure that knocking does not take place due to varying fuel mixtures (gasoline mixtures vary from tank to tank and with seasonal bends), engine wear, carbon buildup in the cylinders, etc.

98 Modes of Operation of the EFI Automobile Engine. [ 1] Normal Operation Mode. The normal operation mode occurs when the engine is warmed up and the car is driven normally. In actuality, the engine does not have to be fully warmed up; it is only necessary that the heated oxygen sensor (HO2 sensor) is heated up to around 600 degrees, which is necessary for its proper operation. Once the HO2 sensor is heated up, the ECU goes into what is called closed loop operation. In closed loop operation, the ECU continuously monitors the HO2 sensor output and adjusts its pulsing of the fuel injectors in order to achieve the correct air/fuel ratio; that is, the desired value of lambda from its engine control map. As a general rule, the “correct” air/fuel ratio is a little on the rich side of the stoichiometric ratio. This setting minimizes pollution and optimizes performance, when used in conjunction with the catalytic converter and other emission control equipment on the vehicle. The value that the ECU uses to pulse the fuel injectors is known as the fuel trim. The whole idea is that the HO2 sensor feeds back data as to whether the engine is running rich or lean (the lambda) and the ECU dynamically uses this data to keep the engine running at an optimum level. This is the way that the manufacturer can guarantee to the EPA that the vehicle is performing its emission control functions optimally, even as gasoline blends change, ambient temperature and air pressure changes, and parts of the engine wear and degrade over the life of the vehicle.

99 [2] Cold Cranking Mode of Operation. Cold cranking is that mode of operation when the engine is first started up and the HO2 sensor is not yet warmed up to operating temperature. In this mode of operation, the engine operates off of a fixed set of parameters in the engine control map of the ECU. When the engine is cold, the fuel that is injected does not vaporize well and exists in the cylinder as microscopic droplets of liquid fuel and not as a vapor. This means that only the molecules of fuel that are on the surface of each droplet can come in contact with oxygen from the air and burn. The fuel that is inside of each droplet cannot burn until the surface molecules are burned away. This condition requires a very rich air/fuel mixture to be introduced into the cylinder in order to provide enough surface molecules of fuel to provide sufficient power to crank the cold engine over. The cold cranking mode of operation lasts only a very short while on any cold start, and represents a very small part of the overall engine operation. It is therefore acceptable to the EPA for it to be inefficient, as long as the HO2 sensor heats up rapidly and transitions the ECU into closed loop operation in a short period of time.

100 3.] Wide Open Throttle Mode of Operation. Wide open throttle (WOT) is the mode of operation that occurs when the driver presses down hard on the accelerator, e.g. for passing in a hill. In this condition, the driver wants the car to accelerate immediately; wants a surge of power, as opposed to the engine gradually building up power as it would in normal mode of operation. WOT requires an overly rich fuel mixture to ensure maximum combustion and to prevent the engine from getting too hot (rich cooling) and from fuel-starvation misfiring under heavy load. In older, carbureted engine designs, rapid depression of the accelerator would cause an accelerator pump to force a highly enriched air/fuel mixture into the intake manifold. This would ensure that the maximum amount of fuel was available to burn in the cylinder on the power stoke, even if a lot of the fuel was wasted in the process. The rapid change in manifold pressure would additionally activate a vacuum advance mechanism on the distributor to alter the normal ignition timing to prevent the engine from knocking during WOT.

101 In modern EFI engines, the ECU senses the rapid depression of the accelerator (or the rapid opening of the throttle) and uses pre-determined values in the engine control map to immediately enrich the mixture and change the ignition timing as well. Consequently, the engine is operating open loop for the brief time that it is in WOT (until the driver eases off the accelerator). Like the cold cranking open loop mode, the WOT mode is inefficient from a fuel economy and pollution perspective, but this is tolerable as the engine is expected to be in WOT mode only for a very small part of its total operation. Summary of Modes of Engine Operation. So, a modern, EFI engine on an ordinary automobile that is designed to run on gasoline operates mostly in a closed loop mode of operation. In this mode of operation, the ECU is not dependent upon fixed air/fuel values in a map that has been pre-engineered with the assumption of a certain type of fuel. Rather, the ECU uses the HO2 sensor to dynamically keep the engine running at the optimal air/fuel ratio as determined by actual measurement and not based upon any assumptions. This factor is critically important in understanding what happens when ethanol is blended into gasoline in various mixtures, and how a flex fuel automobile is able to deal with high ethanol blends. It is also important that the open loop modes of operation not be ignored. They are used only a very small percentage of the time, but when they are used, the ECU is running off of pre-determined parameters and is not able to adapt to differing fuel blends, unless special provisions are made to do so (as in a flex fuel vehicle).

102 increasing the ethanol blend beyond E15 in an EFI engine that is not an FFV will, in all likelihood, cause no damage to the engine and little or no degradation in performance (the performance might increase, in fact; particularly if the EFI can dynamically adjust the ignition timing to make better use of ethanol’s very high octane rating). The fuel mileage will likely suffer because ethanol is an oxygenated fuel and, particularly, if the ignition timing is not dynamically alterable. The engine will run well in normal operation, but may have some starting problems on cold mornings and may misfire and overheat when accelerating very hard.

103 Fuel system corrosion We will read in many places that ethanol is more corrosive than gasoline. This is a somewhat misleading and inflammatory statement. Ethanol is an excellent solvent and will certainly attack substances that are unaffected by gasoline. Ethanol is also miscible in water and any water carried by ethanol fuel may corrode parts of the fuel system. However, ethanol designed to be blended with gasoline must be dried (anhydrous), so water should not be a problem, unless the fuel is sitting around exposed to the atmosphere for long periods of time. The bottom line here, though, is that the E10 standard has been around since the 1990s, and automobile manufacturers have had to address these issues even with a low ethanol blend.

104 Vapor lock: you will find claims that ethanol will cause vapor lock in a non-FFV owing to its Read Vapor Pressure rating. Any EFI fuel system is already sealed for evaporative emission control (EVAP) and this prevents vapor lock, whether for gasoline or ethanol or any other fuel for that matter. Phase separation: ethanol is miscible in water and gasoline is not. It has already been mentioned that ethanol must be dried in order to mix with gasoline. If the mixture then comes in contact with water, the ethanol will “bond” with the water (figuratively, not chemically) and, if the water content gets above a few percent, the ethanol-water mix will separate out from the gasoline (phase separation). The resulting ethanol-water mix will be high in ethanol content and the gasoline part will be low in ethanol content. Some people claim that this will have no effect on engine performance, based upon the discussion of closed loop operation, above. However, problems with cold start and WOT, which are open loop modes, could then be expected to occur if the fuel phase-separates.

105 Ethanol is an excellent solvent. Gasoline has lots of impurities in it. An engine that has been running on gasoline for a long time (say 40,000 miles or more) may have a varnish of gasoline impurities coating the fuel system components. If ethanol is then placed in the gas tank, it may dissolve off the varnish which will travel, in clumps of gunk, into the fuel filter and clog up the fuel system. Once again, automobiles built in 2001 or later will have some protection against this varnishing action. For older cars, it is recommended that ethanol be blended into the gasoline in steps and that the fuel filter be replaced after the highest operating blend is reached. Fuel Line Clogging

106 Flexible Fuel Vehicle Flexible Fuel Vehicles, also known as FFVs, are designed to run on gasoline, E85, or any combination of the two. The “Flexible” nature of the vehicle gives the driver the flexibility to switch back and forth between gasoline and E85. How can this be? Ethanol contains more oxygen than gasoline. The vehicles come equipped with an oxygen sensor which determines the amount of ethanol in the fuel at any time. It provides this information to the onboard computer, which then adjusts the engine to maximize efficiency and performance. The fuel may contain anywhere from zero to 85% ethanol. FFVs are widely available and include sedans, minivans, SUVs, and pickup trucks.

107 Utilization of Alcohol Fuels in Compression Ignition engines difficulties encountered:- 1.More alcohol fuel than diesel fuel is required by mass and volume. 2.Large percentages of alcohol do not mix with diesel fuel, hence use of diesel-alcohol blends is not feasible. Also, the blends were not stable and separate in the presence of trace amounts of water. 3.Alcohols have extremely low cetane numbers, whereas the diesel engine is known to prefer 4.high cetane number fuels (45±55) which auto-ignite easily and give small ignition delay. 5.Diesel fuels serve as lubricants for diesel engine. Alcohol fuels do not have the same lubricating qualities. 6. The poor auto-ignition capability of alcohols is responsible for severe knock due to rapid burning of vaporized alcohol [1,4] and combustion quenching caused by high latent heat of vaporization and subsequent charge cooling

108 Alcohol-Diesel dual fuel operation. The ignition of alcohol in dual fuel operation is ensured by the high self-ignition diesel fuel. The most common methods for achieving dual fuel operation are 1. Alcohol fumigation : the addition of alcohols to the intake air charge, displacing up to50% of diesel fuel demand. 2. Dual injection : separate injection systems for each fuel, displacing up to 90% of diesel fuel demand. 3. Alcohol±diesel fuel blend : mixture of the fuels just prior to injection, displacing up to25% of diesel fuel demand. 4. Alcohol±diesel fuel emulsion : using an emulsifier to mix the fuels to prevent separation, displacing up to 25% diesel fuel demand.

109 Alcohol Fumigation Fumigation is a method by which alcohol is introduced into the engine by carbureting, vaporizing or injecting the alcohol into the intake air stream. This requires the addition of a carburetor, vaporizer or injector, along with a separate fuel tank, lines and controls. Fumigation has some following advantages: 1. It requires a minimum of modification to the engine, since alcohol injector is placed at the take air manifold. Also, ¯ow control of the fuel can be managed by a simplified device and fuel supply system.

110 2. The alcohol fuel system is separate from the diesel system. This flexibility enables diesel engines, equipped with the fumigation system, to be operated with diesel fuel only. The engine can switch from dual fuel to diesel fuel operation and vice-versa by disconnection and connection of the alcohol source to the injector. 3. If an engine is limited in power output due to smoke emissions, fumigated ethanol could increase the power output because alcohol tends to reduce smoke. This is because of good mixing of the injected charge with alcohol. 4. Fumigation can substitute alcohol for diesel fuel. Up to 50% of the fuel energy can be derived from alcohol by fumigation

111 The engine used for this study was a single cylinder, four stroke, direct injection, variable compression ratio, diesel engine with a swept volume of 582 cm 3. The engine is naturally aspirated and water cooled. The engine was coupled to an electrical generator through which load was applied by increasing the field voltage. A fixed 208 injection timing and 18 compression ratio were used throughout the experiments. Indicators on the test bed show the following quantities which are measured electrically: engine speed, brake power and various temperatures

112 Experimental apparatus and test procedure

113 Fig. 1 shows a schematic of the ethanol fumigation system. Ethanol was fumigated into the intake air charge and introduced in the engine as a vapor or mist, dependent on the degree of vaporization which occurred. A simple fumigation system was used, consisting of a single hole, direct opening configuration spraying nozzle. It was selected to achieve ethanol delivery at relatively low pressure. The nozzle has a diameter of about 0.25 mm. Since the obtained nozzle flow rate was relatively high, the produced ethanol jet was allowed to hit a partition in order to get ethanol

114 mist which is directly mixed with air before entering the engine. An electrically driven air compressor was used to supply ethanol to the nozzle. The nozzle was positioned approximately 50 cm ahead of the inlet manifold. This allowed the ethanol to be mixed with the intake air for a sufficient period, providing uniform mixing. The intake manifold was provided with a transparent window for optical inspection of the ethanol±air mixture. Particulate exhaust emissions were drawn using a special sampling probe. Particulates were collected on Teflon- coated glass fiber filters. The filters, manufactured by Pall flex Products Corporation (Type TX40 HI20-WW), measured 25 mm in diameter and were held in a 25 mm Filter holder which is connected to the diffuser end by a copper elbow fitting.

115 An electrically driven air compressor was used to make a vacuum such that exhaust particulates can be extracted continuously from the main exhaust flow and collected on the filter. The flow through the filter was maintained nearly constant by using an orifice at the outlet of the sampler. This ¯ow was measured by using an air ¯ow meter. The exhaust gas was sampled and analyzed using a `Sun Gas Analyzer' (SGA1000). The gaseous pollutants treated in this study where CO, CO2, and HC. The concentration of each gas is measured relative to the sample taken continuously and digitally

116 Results and discussion The physical properties of diesel fuel are changed when ethanol is added in solution (blend). The addition of ethanol causes the viscosity of diesel fuel to decrease. Also, the addition of ethanol in solutions with diesel fuel causes the cetane rating to drop and the heating values to be lower.. Evaporation of ethanol in the intake air (fumigation case) lowers the intake mixture

117 temperature and increases it's density. Thus, as more air is made available in the cylinder, greater amounts of power can be generated if the right proportion of fuel is added. Figs. 3 and 4 show the e€ect of ethanol substitution on CO and HC production, respectively. The maximum increase in CO and HC emissions was at 20% ethanol for both the fumigation and blends methods. Also, the CO and HC emissions were always higher when using the blended fuels than when the engine operated with fumigation. For 20% ethanol fumigation, the increase in CO emissions was in the range of 21±55% at the speed range used, and for 20% ethanol as a blend with diesel fuel, the increase in CO emissions was in the range of 28±71.5% at the same speed range used. The increase in the CO levels with increasing ethanol substitution is a result of incomplete combustion of the ethanol±air mixture. Factors causing combustion deterioration (such as high latent heats of vaporization) could be responsible for the increased CO production. Combustion temperatures may have had a signi®cant e€ect. A thickened quench layer created by the cooling e€ect of vaporizing alcohol could have played a major role in the increased CO production.

118

119

120

121

122

123 The optimum percentage of ethanol appears to be 20 and 15% for ethanol fumigation and ethanol-diesel fuel blends operations, respectively. The use of 20% ethanol as a fumigant can produce an increase of 7.5% in the brake thermal efficiency, 55% in CO emissions levels and 36% in HC emissions levels. Also, this fumigation percentage produces a decrease of 48% in engine smoke and 51% in soot mass The use of 15% ethanol as a blend with diesel fuel can produce an increase of 3.6% in brake thermal efficiency, 43.4% in CO emissions and 34.2% in HC emissions. It can also produce a reduction of 33.3% in engine smoke and 32.5% in the soot mass concentration. The maximum increases and decreases mentioned in the above results are over the entire speed range chosen. Conclusions


Download ppt "INTRODUCTION In this century, it is believed that crude oil and petroleum products will become very scarce and costly. Day-to-day, fuel economy of engines."

Similar presentations


Ads by Google