Ethanol for fuel use india

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As a biofuel additive to petrol, ethanol has been studied in India and is also comparable with butanol.

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Ethanol for fuel use india

  1. 1. CASE FOR AN ETHANOL FUEL ECONOMY IN INDIA     In the big Indian metropolis, sky overview has suffered due to the onslaught of the heavily polluting particles both from the transport vehicles and the industries. The nation has to meet a heavy oil import fuel bill year after year. The ready answer seems to lie in a transition to a clean ethanol fuel economy. This study gives a meaningful insight into the wholesome aspects of ethanol in the backdrop of a localized environment The expanding socio-economic burden of public transportation unfolds a genuine realization for pressing into service the eco-friendly fuel substitutes. Along this direction, several initiatives have already been advocated, prominent amongst which is the transition to the Compressed Natural Gas (CNG). Lately though, Ethanol is a possible contender in the quest for a clean fuel. Whatever be their comparative merits over the conventional petroleum fuels, their incorporation within a larger domain seems to be inevitable at some immediate point in future. However, the mute question is whether the switchover to these fuels should be a rush through process or a seriously thought out exercise. This feeling crops up in the backdrop of the occasionally arising problems, still faced by the users of the CNG vehicles. The path forward seems to be rolled out for a large-scale commercial production of ethanol fuel, with the recent commissioning of two pilot plant facilities in two most prominent sugar cane belts in the country, i.e. Maharashtra and Uttar Pradesh. This study tries to give a meaningful insight into some of the key aspects like the physical potential, production techniques, utilization modes, safety aspects, and importantly, the broad policy-cum-planning frameworks governing the use of Ethanol. Table1: Comparison of Fuel properties Parameter Petrol Diesel Ethanol Energy Content (MJ/Kg) 43.65 45.15 29.73 Liquid Density (Kg/Litre 0.735 0.843-0.848 0.77843 32.1 38.16 23.32 37-205 140-360 79 Octane# 91-97 25 111 Cetane# 0-5 45-55 5 Energy Density (MJ/Litre) Normal Boiling Point (C) 1
  2. 2. Justification for ethanol as a fuel substitute The escalating oil import bills, dwindling fossil fuel reserves, burgeoning pollution levels, deteriorating health standards, and above all, a strong urge for using green fuels are amongst the very strong indicators to dictate a change from a purely fossil fuel mode to that based on a blend of both gasoline and ethanol. In this direction, the desired platform has already been laid out in India too, and the initiative may well be ticking forward towards an ethanol-based economy. In the longer run then, it may be a resource mix of gasohol and natural gas etc. The longterm Implications of this dual fuel economy mode may finally be seen in the context of a growing level of urban environmental pollution levels. Today, ethanol banks upon quite a few successful experience of use in transport mode across several countries like Brazil, USA and Canada. In India too, trial runs of gasohol in the public transport vehicles have, by and large, shown quite encouraging results. The clear advantage of trying this fuel on a large scale is also manifested in abundantly available local reserves of sugarcane production. If viewed realistically, the issue is not so much about he practical utilization of ethanol, but much more importantly, the broad policy framework, within which, its larger use can become possible. So, while examining the alternate fuels in their newfound role, it is quite suitable to talk of optimum use of production capacities available in the market place today. Accordingly, the desired leverage for switching to the ethanol fuel economy may not be all that difficult to provide. This calls for a multi pronged approach to create a necessary user interface for the fuel to be talked about in much more broader terms and also to intensity the efforts for strictly monitored field performance evaluation exercise. Table 1 gives a brief comparative evaluation of the basic properties of conventional petroleum fuels vis-a-vis ethanol. Table II Basic characteristics of the alternate fuels Compressed Ethanol Natural Gas (E85) (CNG) Chemical Structure CH4 Primary Methane Components Liquefied Liquefied Natural Gas Petroleum (LNG) Gas (LPG) CH3CH2OH CH4 Denatured Ethanol and Gasoline C3H8 Methane that is cooled Propane cryogenically Methanol (M85) CH3OH Methanol and Gasoline Main Fuel Source A by product Corn of petroleum Underground grains of Underground refining or reserves agricultural reserves natural gas waste processing Natural gas, coal or woody biomass Energy 29,00 Btu 63,350 80,460 Btu 73,500 Btu 84,500 Btu 2
  3. 3. Content per Gallon Energy Ratio 3.94 to 1 or 1.42 to 1 or 1.55 to 1 or 1.36 to 1 or 1.75 to 1 or Compared to Gasoline 25% at 300 psi 70% 66% 74% 57% Liquid or Gas Gas Liquid Liquid Liquid Liquid Table III Chronology of key milestones concerning ethanol development globally Period Key Development 2500 B.C  Familiarity with the techniques to brew beer in Egypt/ Mesopotamia 1914  First known streamlined study to produce ethanol through the hydrolysis of Cellulose began in Germany 19201940  Intensive experimentation with and use of a variety of important fuel substitutes were undertaken in Argentina, Australia, Cuba, Japan, New Zealand, Philippines, South Africa and Sweden Alcohol blends were more or less satisfactorily used with nearly 4 million vehicles with scope for further utilization ahead Legal sanction granted to the use of Ethanol for fuel purposes All duty and other restrictions on such use removed to promote ethanol Heavy costs were met in the European Govt. sponsored programmers for the development of an ethanol production industry Cost of alcohol averaged abut 44 cents/gal, indirect comparison to cost of gasoline at about 9 cents/gal      The family of alternate fuels The immediate family of alternate fuels comprises of the Liquefied Natural Gas (LNG), Compressed Natural Gas (CNG), Liquefied Petroleum Gas (LPG), ethanol, methanol and several other bio-fuels. Nearly all these fuels have been used for one purpose or the other, though with varying degree of success and geographical outreach. For example, Brazil has been the front-runner in the use of ethanol, perhaps due to its early realization to make an optimum use of its record sugarcane production. Needless to say, molasses derived from the sugar cane happens to be the most well adopted route to produce ethanol. Today, new leads in the emerging area of alternate fuels have to be worked out with still greater emphasis from all key considerations. Yes, in terms of the safety aspects 3
  4. 4. too, it is no longer a hidden view that matters. Transparency of actual use on the liquid fuel end may be more fulfilling, as more and more demand for the conventional gasoline fuel may not seem completely logical in the longer run. Table II summarizes the key characteristics of the alternate fuels. The early days of ethanol Mankind's association with ethanol started quite early on in to the actual phase of this all important fuel development. So, no wonder that it has transgressed several stages to reach a level of technological maturity, though not in a full measure. Few important issues are still waiting redressal, prominent amongst which are the techniques to blend ethanol in diesel. A case in point is India, whose consumption of diesel is almost 7 times more than that of the gasoline. So, if suitable techniques become available to do so, country could manage to save large chunk of foreign exchange as well, apart from curbing pollution to a reasonable level. Table III traces the origin of ethanol right from the world war days to the modern times. From 1977 onwards, key current achievements of a few important country programmers have been mentioned separately. Safety considerations of ethanol and other fuels As against an intimate understanding of the conventional petroleum fuels, the new class of alternate fuels is relatively new in the public memory. For this purpose, it seems quite necessary to list down their associated safety aspects at some length. Table IV indicates the key features as well as the accompanying safety guidelines of the alternate fuels from a user perspective, Production routes for ethanol Ethanol by definition is a clear, colorless liquid with a characteristic, agreeable odor. However, in dilute aqueous solution it possesses a somewhat sweet flavor and yet in concentrated solutions offers a burning taste. Typically, ethanol (CH3CH2OH) is a group of chemical compounds whose molecules contain a hydroxyl group, -OH, bonded to a carbon atom. Ethanol produced from cellulose biomass materials in place of the traditional feedstocks (starch crops) is known as bioethanol. In this age of fascination for renewable energy sources, ethanol also qualities for equal attention, due to its being a cleaner burning fuel. A novel feature of ethanol lies in its extraction from a very broad range of raw materials. These primarily include the growing crops, vegetable matter, industrial waste like the sulphite liquor from paper and pulp industry, and quite importantly, molasses from the sugar industry, besides waste organic matter such as straw and sawdust, cassava, agricultural waste, rotten fruits etc. The predominant source of ethanol production in India is from the molasses. Nearly 270 distilleries operating at about 50% of their installed capacity are engaged in such production. Lately, cassava is also being mooted as an effective way to obtain this clean fuel. Process flow for ethanol production 4
  5. 5. There are several methods available to produce fuel ethanol, but the prominent route to produce this important fuel is through the following steps. Each of these steps is based on one chemical process or the other, without any major complexity involved. Presently, dry milling and the wet milling methods are the most common techniques employed for the purpose, as highlighted with the individual processing steps in Table V below. Principal advantages of ethanol blended gasoline as an automotive fuel Ethanol by itself is not feasible as a complete motor vehicle fuel due to several reasons. These include its lower calorific value, higher surface tension, greater solvent power etc. But due to the presence of oxygenates in ethanol, it makes a very suitable blended fuel with gasoline on account of the following few considerations:          Higher latent heat of vaporization Uniform composition Higher flash point Very high octane rating No hazardous component Higher compression operation of the engine Reduced particulate emissions Enhanced engine power output & efficiency Increased safety during use Table IV Features/safety guidelines of alternate fuels Compressed Natural Gas (CNG)  Odorless Ethanol (E85)  Less Volatile than Gasoline due to denaturing of the ethanol component  Being corrosive to some metals, gaskets and seals, use of anti-corrosive elements is required Liquefied Natural Gas (LNG)  No addition of Odorants possible Cooled cryogenically to about - 260degreeF  Use Methane gas detectors for detection of any leakages Avoid direct physical contact due to possible incidence of getting     Add Odorants to detect any leaks/spills Use only heavy storage tanks to avoid possible hazard 5
  6. 6. frostbites Liquefied Petroleum Gas (LPG)  Extremely volatile, more volatile than Gasoline  Odorizing required besides use of gas detector for leaks or spills Methanol   Low flame luminosity Prevent Inhalation/ingestion  Avoid use of Corrosion Prone elements Table V: Production Steps in ethanol Processing Stage Process Features Remarks Milling  Hammer Mills grind the passing feedstock into a powdery mass  Grain size should be small Liquefaction  Inter-mixing of the mass with water and alpha amylase Passage via the cookers maintained at a high temperature stage (120 150 degree C) followed by a low temp, holding period (at 95 degree C) Liquefaction of the starch occurs via the heat applied  Presence of the high temperatures reduces the bacteria levels in the mash   Saccharification  Cooling of the mash available in the cookers followed by the addition of secondary enzyme i.e. gluco-amylase  The addition converts the liquefied starch into the useful fermentable sugars (Dextrose) Fermentation  Addition of the years to the mash so as to ferment the sugars to ethanol and carbon di-oxide  Within a batch fermentation process, the mash is retained in one fermenter for nearly 48 hrs. prior to the ending of the distillation 6
  7. 7. process Distillation  The fermented mash known as Beer constitutes of about 10% alcohol, along with the non - fermentable solids from the corn and yeast cells  Removal of alcohol takes place from the solids and water Dehydration  Moisture, if any, present in the alcohol obtained above is removed by passing it through a dehydration system  Pure alcohol finally obtained is in an anhydrous from and is about 200 proof Denaturing  Alcohol is made unfit for human consumption by denaturing it with a small (2-5%) of gasoline  Pilferage for human consumption drastically reduced By-products  CO2 (in large quantity) and Distillers grain are produced during ethanol production  Alcohol free Co2 is utilized by ethanol plants after proper compression for sale as carbonate beverages or for other purpose In comparison, the distillers grains have a high protein content along with other nutrients for high value use or percentage demonstration  Global experiences with ethanol fuel utilization To carry the chronological order of ethanol use in present day terms, it is important to look at a few key country programmers in this direction. These countries include USA, Canada, Sweden and Brazil, within which ethanol is primarily used as a blend component in levels ranging between 10-85%. Currently, the gross annual world production of non-beverage ethanol is between 8-20 billion liters. Bulk of such production originates from America and Europe. In terms of the number of vehicles running on alternate fuel today, Brazil tops the list with a record number of more than 4 million ethanol vehicles, followed closely by USA at 4.03 7
  8. 8. lakhs & 3.0 lakh CNG vehicles in Italy. Additionally, near about 3.8 million vehicles are using propane - yet another good fuel substitute. U.S. program on ethanol fuel Ethanol came into active use in USA way back in 1977, following the promulgation of the Clean Air Act. Corn, which is primarily a starch based feedstock, is mainly used (>90%) to derive ethanol. This way, ethanol takes up about 7% of the US corn and contributes only 1/10th of 1% of US energy consumption. Here, about 4 billion liters of ethanol are produced from corn annually with ethanol blends making up nearly 12% of the total gasoline market today. As per the futuristic projections, about 14 billion gallons of bio-ethanol is expected to replace around 348 billion barrels of oil in US by 2020. Likewise, about 2.45 billion MT/year of available ligno cellulosic biomass offer a ready potential of producing about 1.2 trillion liters of ethanol per annum. The Brazilian experience Brazil spearheads the utilization of ethanol in the world today. Ironically, fuel ethanol has been put to use in this country in differing proportions since 1931. Amongst the significant objectives laid under the ambit of the National Alcohol Program was to enhance and maintain the blend proportion of anhydrous ethanol to about 32% in volume, in all gasoline sold there. Fulfillment of this target came as early as 1983, enabling Brazil to lead the initiative of banning the use of tetra-ethyl lead as an octane booster to gasoline. During 1998-99, Brazil produced an estimated 15 billion liters of fuel ethanol from sugarcane, thus resulting in savings of about 2,50,000 barrels of gasoline imports in addition to reducing emissions of the deadly carbon dioxide and other pollutants. Today, about 15% of the vehicles with spark ignition engines operate on neat ethanol (E85) with the rest using a blend of 24 % ethanol (gasohol) in gasoline. The Indian perspective Presently, India is the largest sugarcane producer in the world, followed closely by Brazil. As per indicative estimates, the country has a total installed production capacity of about 2825 million liters of ethanol per year as against the total requirement for potable, industrial and other uses of about 1200 million liters. This is one major reason to focus on the operation of ethanol fuelled vehicles. Yet another major reason for a possible switchover to gasohol is manifested in the alarming levels of vehicular pullution. The number of vehicles has registered a sharp increase more so, during the last decade. In Delhi alone, the vehicle number has crossed about 4.6 million. Today, the vehicular pollution contributes roughly 64 % of total air pollution in Delhi, followed closely by Mumbai at 52% and somewhat controlled figure of 30% for Kolkata. About 50% of the total petroleum products consumed in the country go into the transport sector mainly in the form of highspeed diesel and gasoline. Significantly, emissions from vehicles include about 1/5th carbon di-oxide, regarded as a major contributor to global warming. Besides, oxides of sulphur (SOx) and nitrogen (NOx) precipitate acid rains, in addition to suspended particulate matter etc. posing grave health risks. So, all the above-mentioned facts provoke a strong need 8
  9. 9. for bringing in an ethanol outlook. Table VI indicates the basic justification for bringing in an alternate fuel resource economy in a true sense. The early ethanol program leads in India The early threads towards ethanol program development were picked up way back in 1979, with the constitution of an inter-departmental committee for probing the feasibility of ethanol blended gasoline. This committee set up by the then Ministry of Petroleum, Chemical and Fertilizers mooted the initiation of a few major R&D programmes. To start with, trial runs were conducted on about 15 passenger cars in an active collaboration with the Indian Institute of Petroleum, Dehradun. These specific trials conducted especially in 2 wheelers and 3 wheelers used ethanol in gasoline to the tune of 10-20%. To redress the problem of ethanol not mixing easily with diesel, IIP developed retrofit kits to substitute diesel oil in the buses. A trial run of these kits was carried out on about 25 buses of Delhi Transport Corporation (DTC) during 1986-88 under the ambit of a then ONES programme. It was reported that these initial runs resulted in replacement of about 11 % of diesel oil and 25 % reduction invisible smoke emissions. The results of the initial trials were quite encouraging with upto 30 % of the reduction in hydrocarbon emissions. However, availability of ethanol blending in gasoline came up as a major bottleneck. Following this, MNES sponsored a 3-year project to the Indian Institute of Technology (IIT), Delhi, under which a trial run of about 100 vehicles of Delhi administration was envisaged. The other partnering organizations in this' programme were the MNES, Indian Oil Corporation and Delhi Administration. Vehicle of different makes were used for the purpose of carrying over an ethanol blended gasoline between 5-10%. During the period between February 1993 to August 1995, nearly 18 lakh kilometres of cumulative distance was recorded by these vehicles. The major benefit being the reduction in carbon monoxide and hydro carbon emissions with engine position more or less remaining intact. Additionally, this experiment resulted in savings of about 20 kilo liters of gasoline during the trial runs. Table VI Key facts and figures concerning the Indian oil Sector Crude oil imported during 2000-2001  107 million tons Percentage of total crude oil requirement  Around 70% Average price of Oil per barrel  $25-30 (with a high of $37 per barrel) Oil Import Bill during 20002001  Rs.80,000 Crores Total installed capacity of alcohol production in India  3.2 billion liters Average annual production of alcohol per year  1.3 billion liters 9
  10. 10. Efforts at initation of the country programme    Early leads in 1977 4 committees and 6 technical studies matured so far Nor formal arrangements still forged between the petroleum and sugar industries Provision for mixing of ethanol with gasoline  BIS specifications provide for upto 5% mixing of ethanol with gasoline at present Initiation of pilot plant projects  3 such projects already identified at Miraj, Manmad (both in maharashtra) and Bareilly (Uttar Pradesh) Indicative requirement of anhydrous alcohol per year for blending  Nearly 400 million liters The path forward for a sustainable ethanol fuel programme in India The renewed faith in ethanol as an effective gasoline blended fuel is certainly a welcome step. With the recent commissioning of the pilot plant facilities at a few locations, more and more such initiatives should be forthcoming. The initial runs with gasohol (5% ethanol base) could be extended on a large scale, but only with the requisite infrastructure availability in place. The crucial linkage in this whole chain of enforcing an ethanol fuel economy is just not the lead players in the oil sector, but an amalgam of the distilleries, R&D organisations and testing cum evaluation centres and quite importantly, the policy planners. Further, what is required is to alter the exiting BIS specifications, so as to allow for an increase of the ethanol blending percentage in gasoline from existing 5% to 10%. Also, the need is to replicate the facilities at the above-referred pilot plant facilities at many other places too, so that the availability crunch does not arise, like the one witnessed in case of CNG fuel today. Writer: H.P. Garg 10

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