Emerging Scope for Biodiesel for Energy Security and Environmental Protection

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1 Emerging Scope for Biodiesel for Energy Security and Environmental Protection Sukhwinder Singh 1, Dr. S K Mahla 2 1 Mechanical Engg. Deptt., KC College of Engg. & IT, Nawanshahr. 2 Mechanical Engg. Deptt., GGS College of Modern Technology, Kharar. Abstract---The global fuel crisis in the recent times has generated awareness amongst many countries of their vulnerability to oil embargoes and shortages. Considerable attention has been focused on the development of alternative fuel sources. The Motor vehicle population has also increased tremendously over the last decade in India. Environmental degradation is another outcome of growth in motor vehicle population. One of the strategies adopted to curb deteriorating environmental quality is the use of alternative fuels like Ethanol and biodiesel. Bio-Diesel is being looked upon as a renewable source of energy, which can partially substitute the diesel fuel. Special interest is being shown in view of the potential of this fuel to provide energy security and environment protection. Biodiesel, alkyl ester of fatty acids derived from vegetable oils, is emerging as a technically feasible, economically competitive and environmentally sustainable alternative to diesel. The base catalyzed continuous transesterification of vegetable oils having low viscosity, low free fatty acids and low saturated oil- glycerides is currently the preferred process for biodiesel production. India, continue to have shortage of petroleum products including diesel. We cannot divert our edible oils for biodiesel production due to their continued shortage and are consciously developing biodiesel based on nonedible oils. The efforts being made to have the prospect of providing India a leadership position in renewable energy. However, massive efforts and active multi-agency participation are required for techno- commercial success of biodiesel in India. Keywords: Biodiesel, non-edible, trans-esterification, blending, emission, I. INTRODUCTION In India, the present level of diesel consumption is about 65 Million MTs and in the recent past, the annual incremental consumption of diesel has been in excess of 5 percent. Since more than three decades, we have been witnessing continually increasing crude oil price in the world market coupled with our increasing (>67 percent) dependence on import to meet our requirement which promoted us to look for alternative fuels for substituting diesel. The important approaches that are at various stages of their development, adaptation and implementation towards diesel substitution in automobile sector are related to the use of Compressed Natural Gas (CNG), Liquefied Natural Gas (LNG), Compressed Natural Gas in Combination with Hydrogen (CNG+H2), Dimethyl Ether (DME), and Anhydrous Alcohol as well as Industrial Alcohol in combination with chemical additives and the Biodiesel as shown in TABLE-I. Recently, the biodiesel based on non-edible oil stocks has been emerging as a technically feasible, economically competitive, environmentally sustainable and socially beneficial substitute automotive fuel for diesel. The properties of bio-diesel like high cetane number, low sulphur content and better lubricity than petro-diesel make it an excellent fuel for diesel engines. The various engine and vehicle tests conducted so far indicate the vehicle performance to be satisfactory with blends up to 20% of bio-diesel in diesel. The emissions of carbon monoxide and particulates are also lower with bio-diesel and petro- diesel blends. Opportunities for availing benefits for carbon credits exist on account of lower carbon dioxide emissions with use of bio-diesel. The better lubricity of bio diesel would be of help particularly when we shall be reducing sulphur further in line with Euro III and Euro IV norms. While blends up to 20% are quite common abroad, the Indian vehicle manufacturers are initially apprehensive and recommend to use only 5 or 10% of bio-diesel in diesel. In any case, the bio-diesel is not likely to be available in large quantities in near future, the phased approach of introducing 5% bio-diesel in diesel in the first phase may be an appropriate step. II. BIODIESEL Biodiesel is essentially alkyl (ethyl /methyl) ester of fatty acids derived from vegetable oils. Biodiesel based on different feed stocks have been tested with promising results in various Countries, e.g., Soybean in America, rapeseed and sunflower in Europe and Palm in Indonesia and Malaysia. 157

2 The renewability, low viscosity, low free fatty acid (FFAs) content, low saturated oil- glycerides content, and high mono-unsaturated oil- glycerides content are the key screening criteria for identification of the most suitable vegetable oil feedstock to produce the biodiesel for use in wide ranging temperature conditions. Removal of unused alcohol, catalyst, water, soaps (if any), free fatty acids, partially or unreacted oil-glycerides is critical to produce the correct biodiesel. A number of processes/ technologies have been developed in different laboratories for the production of biodiesel under both batch and continuous modes, which include: Acidcatalyzed trans-esterification, Base- catalyzed transesterification, and Conversion of oil- glycerides to fatty acids and then their esterification to biodiesel. At present, base-catalyzed trans-esterification with continuous mode of operation under atmospheric pressure is generally utilized which gives more than 98 percent yield. However, the process has limitations with oils containing high free fatty acids and the research is under way on more versatile processes using different feed stocks for production of biodiesel. Biodiesel as an automotive fuel offers several advantages over the conventional diesel, which include comparable energy content, engine performance and mileage. It has no sulfur and polycyclic aromatic hydrocarbons (PAHs) content, apart from being environment friendly with comparable physical and combustion characteristics as conventional diesel and could be used without engine modification as a blended fuel. The higher fraction of biodiesel in the blended fuel may prompt certain modifications in the engine components other than metallic ones. III. BIODIESEL FOR ENERGY SECURITY Oil provides energy for 95% of transportation and the demand of transport fuel continues to rise. The requirement of motor spirit is expected as 13 million MTs in Likewise, the demand of diesel was as 66 million MTs in The domestic supply of crude oil satisfies only 22% of the demand and the rest will have to be met from imported crude. Our dependence on import of oil and petroleum products will continue to increase in the foreseeable future. The crude prices and availability are subject to great volatility depending upon the international situation and, therefore, attempt needs to be made to reduce dependence on imports. Oil security and its continued availability has become an area of extreme concern for the world as a whole and especially for oil importing countries, after the gulf crisis. The volatile political situation can cause supply disruptions, therefore, several countries embarked on programmes for alternative source development. There are already some reports, which suggest that we have achieved the plateau of oil production and in another 2-3 decades the oil resource will become scarce and alternate sources of energy, though expensive today, will compete. With its growing population, India is the sixth biggest in world in terms of energy demand, which is 3.5% of world commercial energy demand and is expected to grow at the rate of 4.8% p.a. of its present demand. IV. BIODIESEL FOR ENVIRONMENT PROTECTION India is committed to implement Euro-III and Euro-IV diesel fuels norms for which an investment of about Rs.65,000 Crores shall be required mainly for upgrading refinery facilities. The investment of a part of this amount on biodiesel could ease our achievement of above-mentioned norms as the vigorous evaluation of biodiesel fuel indicates that the overall smog forming potential, unburned hydrocarbons, carbon monoxide and sulphur dioxide emissions are reduced significantly by the use blended/pure biodiesel. The NOx emission has been found to increase marginally for which certain modifications in the engine parameters shall be required. The results for pure biodiesel (B100) and mixed biodiesel (B20D80) compared to conventional diesel are given below in the form of tables and figures. Table: II Reduction of Emission Using Biodiesel Emissions B100 B20 Regulated emissions Unburned hydrocarbons -93% -30% Carbon monoxide -50% -20% Particulate matter -30% -22% NOx +13% +2% Non Regulated emissions Sulphates -100% -20% Poly cyclic Aromatic Hydrocarbons -80% -13% Nitrated Poly cyclic Aromatic -90% -50% Hydrocarbons Ozone potential of special -50% -10% hydrocarbons Life cycle emissions Carbon dioxide -80% Sulpher dioxide -100% 158

3 TABLE: IV Lowered Emissions of CO and HC All in gm/km CO HC NOx HC+NOx PM BSII limit Base line B B %age improvement in terms of baseline B10 15% 41% 4% 10% 28% B15 20% 50% -12% 10% 38% FIGURE: 1 Impact of Biodiesel on Emission V. BIODIESEL IN INDIA The biodiesel in Indian context offers certain unique technological, environmental, economic and social advantages. However, the development of biodiesel support system for significant benefits is a challenge as well as an opportunity. The salient points for adaptation of biodiesel in India are as follows: (i) Expected Diesel Demand in India In India, about 65 million MTs of diesel fuel have been consumed in year The estimated diesel fuel demand for the last five years along with the requirements of biodiesel for B5, B10 and B20 blend levels is presented in following TABLE III. (ii) Vegetable Oil Production in India The vegetable oil production in India is in continued shortage, compelling the demand to be met by large import. Indigenous edible oil production is greatly dependant on monsoon and shows wide fluctuation as a result, edible oils cannot be diverted for biodiesel production in India. (iii) Non Edible Oils for Biodiesel in India In India, it is neither possible nor desirable to use the edible oils for biodiesel and thus, non-edible oils make the desirable feedstock for biodiesel. Higher cost of the edible oils, prospects for wasteland utilization and up gradation, massive employment potential in rural/ tribal areas, and higher survivability of non-edible oil species under dry and drought conditions are the other crucial factors which make the non-edible oils as the most appropriate feedstock for biodiesel in India. (iv) Prospective Species for Biodiesel In India The species that have been experimented in India for the production of biodiesel include Madhuca Indica, Shorea Robusta, Pongamia Glabra, Pongamia Pinnata, Mesua ferra (Linn), Mallotus Philippines, Garcinia Indica, and Jatropha Curcas. The institution and agencies which are engaged in the work include Punjab Agricultural University; Indian Institute of Technology, Delhi; Indian Institute of Technology, Chennai; Mahindra and Mahindra (M&M); Indian Institute of Science, Bangalore; Indian Institute of Petroleum, Dehradun; Indian Institute of Chemical Technology, Hyderabad; Indian Oil Corporation, Faridabad; Harbinsons Biotech, Gurgaon and several other institutions. The species that have been given priority are Jatropha Curcas, JC (Ratanjyot) and P o n g a m i a P i n n a t a, PP ( Karanja) The s a l i e n t characteristics of these species are as follows: Non-edible oil species, which can grow on wasteland. Can be cultivated as agro-forestry crops. Hardy plants and JC has superior survivability under drought conditions. JC begins yielding seeds by second year and goes on up to twenty-five years. PP begins yielding seeds by fifth year but yield peaks up by three-fold by tenth year and continue till eighty years as compared to JC. Oil-yield is higher for JC (35-40%) as compared to PP (17-22%) and average annual seed-yield is reported to be Kgm per tree for JC (under average conditions) versus kgs per tree for PP (under average conditions) Under average rainfall and after tenth year of plantation, PP gives tons of biodiesel per hectare (assuming plant density of 250) against tons of biodiesel per hectare for JC (assuming max. plant density of 3750) 159

4 The mixed cultivation of JC and PP on wasteland area under average rainfall for high and sustained production of oilseeds from early second year to long 80 years is a desirable option. Single cultivation of JC on droughtprone areas of wasteland could be considered if PP survival in such environment offers problem. (v) Technology Challenges The currently available processes for production of biodiesel include acid catalyzed trans-esterification, base catalyzed trans-esterification and conversion of oilglycerides to fatty acids and then esterification of the produced fatty acids to biodiesel.the existing processes have limitations in terms of efficiency, processability of oils of high viscosity, high free fatty acid content and high-saturated oil-glycerides. The conversion yield, separation of unwanted reaction products and purification of the produced biodiesel are important problems being studied for their effective and reliable solution. The work related to use of enzymes for biodiesel production being carried out in certain Indian Laboratories and the innovative catalyst-free process developed by IICT, Hyderabad shall provide an edge to India in biodiesel production technology with strong possibility of using industrial grade 95 percent ethanol. Similarly, genetic engineering inputs are required for developing high yielding oil species for biodiesel. (vi) Byproduct Utilization The glycerol, fatty acids salts and oil cake are main byproducts from biodiesel production. The research inputs are required towards: Utilization of glycerol for value added products. Use of fatty acid salts as useful surfactants. Study of hazardous properties of oil cake, if any, to process it as fertilizer or to use it as a feed stock for bio-gas generation. This has been under investigation at certain laboratories. VI. BIODIESEL SPECIFICATIONS Most of the advanced countries have finalized their biodiesel specification. In India, Bureau of Indian Standards (BIS) is in the advanced stage of finalization of standard for B100 Biodiesel fuels. The same specifications shall be applicable for biodiesel for blending. Similarly, OEM approvals for blended and B100 biodiesel are in the process through pilot level trials under way at different places. Table: V Characteristics of B5and B20 Compared With Petro Diesel. Properties (Units) BIS1460 B5 B20 Density (g/cm 3 ) Carbon residue (% mass) Max Sulphated ash, (% mass) Max Total sulfur, (% mass) Max Cetane number Min Flash point, ( 0 C) Min Copper corrosion Max Viscosity, 40 0 C (cst) 2.0 to Neutralization value (mg/g) Max Free glycerin (% mass) NA NA Total glycerin (% mass) NA NA 0.05 Phosphorous (% mass) NA Water content (mg/kg) Max VII. PRODUCTION, BLENDING AND DISTRIBUTION India is witnessing and availing the advantages of the improvements, which have been taking place in the diesel engine technology including the automobile sector. These improved engines required bench-marked fuel otherwise their performance and life could be hampered. In India, we are also witnessing growing menace of adulteration in fuels including diesel. In these circumstances, it is desirable that final stage of processing and blending of biodiesel and its subsequent distribution/marketing is carried under the supervision and control of oil companies so that the stringent conformance to specifications is observed and availability of quality fuels to these customers is ensured. The National Oil Companies have to play significant role in this regard. An appropriate model covering the operations: production of seeds, extraction of vegetable oil, production of crude biodiesel and final processing and blending of biodiesel need to be evolved with proper allocation of responsibilities (seed producers, oil/biodiesel processors and the oil-companies) and quality characteristics which need to be ensured at different stages of the operations need to be set for standardization of these operations. 160

5 VIII. CONCLUSIONS Biodiesel fulfils strategic needs of energy of a country like India, which has large dependence on the imported crude. Biodiesel is a tested and proven low emission fuel, which is accepted world over by engine manufacturers, is safer to handle and requires no separate infrastructure for its distribution and marketing. The biodiesel is the alternate to petroleum diesel and has been successfully introduced in several countries in the world. Therefore, biodiesel is an eco- friendly fuel made from the local resources. REFERENCES [1 ] Sharp, C.A, Howell, S.A. and Jobe. J.; SAE Paper No (2000) [2 ] Kumar, R; Ray, S.S.; Tuli, D.K.; Verma, R.P.; and Bhatnagar, A.K.; October, (2002) `Biodiesel production- Transesterification of Vegetable Oils' in "ISFL ", [3 ] Tuli, D.K. and Raje, N.R., November 7-9, (2002, `Biodiesel as an Alternative Transportation Fuels presented in "International-Conference on Biofuels", Taj Palace, New Delhi,) [4 ] "Differential Diesel Alternatives" Indian Oil News, No. xxxxi,feb., ( 2004) [5 ] Report on the committee on development of biofuels, Planning Commision of India, [6 ] Kumar, R., Sharma, M., Ray, S.S., Sarpal, A.S.Gupta, A.A., Tuli, D.K., Sarin, R., Verma RP and Raje, N.R., SAE INDIA 2004 proceedings, New Delhi [7 ] Kumar, R., Ray, S.S Tuli, D.K., Verma R.P., and Bhatnagar, A.K., Oct. 7-9, 2002, Proceedings Third Intl. Sym. Fuels & Lubricants ISFL-2002, New Delhi [8 ] Kumar, R., Ray, S.S. and Tuli, D.K., January 9-12, 2003,Proceedings of PETROTECH-2003, New Delhi. [9 ] Saxena, S, Sep. 2004, Proceedings of International Conference on Biofuels, New Delhi. [10 ] R.K. Malhotra and Rakesh Sarin, 2004 Society of Automotive Engineers Inc. [11 ] O. P. S. Verma and K. L. Patel, 2004 Society of Automotive Engineers Inc. [12 ] S.K. Mahla, L.M. Das, M.K.G. Babu, 2009 "Effect of EGR on Performance and Emission Characteristics of Natural Gas Fueled Diesel Engine", Jordan Journal of Mechanical & Industrial Engg,, Vol. 4, Number 4, Sept 2010, pp [13 ] S.K. Mahla, L.M. Das, M.K.G. Babu,, a. Utilization of CNG and Biodiesel blend in a DI diesel engine, Biomass & BioenergyAbbreviations b. B5 means 5% blend of biodiesel in Diesel c. B20 means 20% blend of biodiesel in Diesel d. B100 means 100% biodiesel 161

6 S.No Substitution Fuel & Extent of Substitution 1. Compressed Natural Gas, CNG (Up to 100 %) 2. Liquefied Natural Gas, LNG (Up to 100%) 3. Compressed Natural Gas-Hydrogen Mixed Fuel,(CNG+H2) (Up to 100 %) 4. Di Methyl Ether, DME (Up to 100 %) 5. Ethanol :(a) Anhydrous (b) Industrial with emulsifier (Up to 10 % ) Table: I Alternative Substitution Fuels For Diesel Nature / Source Non-renewable Oil Fields Non-renewable Mainly through import Major fraction nonrenewable Oil Fields/Che mical Industry Non-renewable Synthesized from natural gas Renewable Sugar Industry/Distilleries Beneficiaries /Remarks National Oil Companies High cost of infrastructure Higher pressure storage in special vessels National Oil Companies High cost of infrastructure Low temperature storage in special vessels National Oil Companies Higher cost of infrastructure Technology at development/trial stage National Oil Companies/ Chemical Processors No need of high pressure/low temp. special vessels for storage Development at laboratory stage Farmers, distillers, chemical industry Under pilot level trials 6 Biodiesel (Up to 20 %) Renewable Agro-product to be processed into finished benchmarked auto fuel Chemical industry and oil companies People in forest and remote areas could be benefited Under pilot level trials Table: III Estimated Diesel Demand and Biodiesel Requirements in India S.No. Year Diesel Demand, million MTs Biodiesel Demand (million MTs) B5 B10 B