TREND TOWARDS CLEANER FUELS : AN OIL INDUSTRY PERSPECTIVE

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1 TREND TOWARDS CLEANER FUELS : AN OIL INDUSTRY PERSPECTIVE S.Nandi, V.K.Chhatwal, R.K.Malhotra and Anand Kumar, Indian Oil Corporation Ltd., R&D Centre, Sector-13,Faridabad Key Words: Fuel Quality, Alternative fuels, Refinery upgradation & emmissions ABSTRACT Future economic growth crucially depends on the long-term availability of energy in increasing quantities from sources that are dependable, safe and environmentally friendly. At present no single source or mix of sources is at hand to meet the specifications. Although India is rich in coal and abundantly endowed with renewable energy in the form of solar, wind, hydro and bio-energy, its hydrocarbon reserve is really small.current reserve-to-production ratio for coal, oil and natural gas are 235, 23 and 35 years respectively. India, like many other developing countries, is a net importer of energy, about 70 per cent of primary energy needs being met through imports mainly in the form of crude oil. As per US based Energy Information Administration s report., world crude oil demand is set to increase 37% by 2030, driven largely by transportation needs. However, Conventional Diesel and Gasoline Technologies for automotive fuel will still be major players for at least next Years. In view of high escalation in crude price and market volatility, steps have been taken by Indian Oil Corporation which was the first among oil company to implement use of alternative fuels viz. Ethanol, Biodiesel and Hydrogen in a big way. The present paper summarizes Global oil scenario,steps taken by Oil Industry in meeting future fuel specifications, clean fuel strategy and studies carried out at our R&D using use of alternative fuels viz. Ethanol-gasoline blends, Diesel-Biodiesel blends & Hydrogen-CNG blends in vehicles. INTRODUCTION Despite world oil prices remaining above $95 per barrel, demand for liquid fuels will increase strongly and much of the overall increase in consumption is projected for Asian countries, particularly India and China, where strong economic growth is expected. In line with European Auto oil programe, which offered cost effective measures to achieve air quality targets for the period , Government of India under the Chairmanship of Dr. R.A.Mashelkar, the then DG of CSIR formulated Indian Auto Fuel policy which proposed Euro-III equivalent emission norms for the entire country to be covered by 2010 and Euro-IV equivalent emission norms to be implemented in major cities from 2010 Oil companies have invested about Rs 60,000 crores to upgrade the fuel quality of Petrol and Diesel so as to meet Bharat stage III and Bharat stage IV specifications, which is equivalent to Euro-III & Euro-IV specifications respectively. Presently our fuel quality is at par with developed countries. Various steps have been taken to introduce clean fuel strategy. e.g. leaded gasoline have been phased out completely from the year 2000, from having a value of 0.56g/lt to

2 0.013g/lt, Benzene limit is narrowed to1% max.,octane increase from 87 to 91, reduction in sulfur from 0.2 % to 0.05%. Similarly in case of Diesel fuel, Cetane has been increased from 45 to 51, reduction in sulfur from 1.0 % to 0.05%,and improvement in distillation from C to T95@ C For improving Gasoline quality following technologies have been installed in refineries :Reformate splitter for separation of benzene rich light cut from rest of reformate ;Isomerisation unit for benzene saturation and octane increase ;Continuous catalytic reforming unit for octane increase and selective desulpharisation for sulfur reduction. Similarly for improving Diesel quality following technologies have been installed in refineries : Diesel dehydrosulfurisation (DHDS) where only sulfur reduction is required ;Diesel hydrotreater (DHDT) for Large sulfur reduction and high Cetane gain coupled with T-95 point improvement and Hydrocracker for middle distillate maximisation along with Cetane improvement and very high sulfur reduction Consumption of petroleum in the world, which started as a few tonnes a year around 140 years ago, has reached over 3000 Million metric tonnes (MMT) per year. In India, it is increasing at a very steep rate from 3.5 MMT in to 175 MMT in As a step forward, Indian Oil Corporation was the first among oil companies in India to initiate studies in alternative fuels assuming depletion of crude oil reserve within next 30 years or so. Following studies were taken up in the area of alternative fuels : 1. Ethanol-Gasoline blend 2. Diesel Biodiesel blend 3. Hydrogen CNG Blend 1 ETHANOL-GASOLINE BLEND : MoP&NG advised IOC R&D to undertake R&D studies using alcohol-gasoline blends on 2 wheelers and passenger cars. Experimental : Commercial gasoline available in Faridabad was selected for the study and ethanol of 99.8% purity was procured from M/s Oudh Distillery, Sitarampur,Lucknow. Apart from neat gasoline two blends of 5% and 10% Ethanol Gasoline blends were made.all the test fuels were evaluated as per IS :.2796:2000 specifications.test results are given in Table-1. Mass emission studies: In India we have adopted emission standards similar to European emission norms for passenger cars and heavy duty vehicles. For 2 wheelers, we have in India specific norms, which are one of the stringent emission norms. Test procedures followed in India are as stipulated in the notifications of Ministry of Road Transport and Highways (MoRT&H). For assessing the emission benefits with blending of Ethanol l in Gasoline, mass emission tests were conducted as per the MoRT&H defined test procedures and driving cycles for two wheelers. 2 wheeler selected for study was Hero Puch with and w/o Cat converter Two wheelers Mass emission testing facility This facility consists of a Chassis Dynamometer and Horiba Motor Exhaust gas analysis system. Chassis Dynamometer is an equipment used to simulate the road loads

3 encountered by the test vehicles in normal operation, inside the laboratory for conducting the fuel economy and emission testing. The major component of the chassis dynamometer are Roll assembly, Torque transducer, Power absorption unit, Power Cubicle and Computer control system. Horiba Motor Exhaust gas analyser system is used for analysing the concentration of each pollutant in the exhaust gas and results are expressed in terms of g/km. The measurement components of this system are constant volume sampler, analytical equipment, drivers aid and data analysis system. Result & Discussions: Mass emission tests were conducted on Hero Puch with and without cat converter following procedure stipulated in MoST (Ministry of Surface Transport) notification using neat Gasoline and Ethanol Gasoline blends. Results of this study are given in Table- 2. Study indicated reduction in Carbon Monoxide (CO) emission from 2 wheelers with the use of 5% and 10% Ethanol Gasoline blends of the order of 7.29% to 27.96% respectively. The large reduction in both CO and HC emissions from 2 wheeler fitted with Catalytic converter is on account of improved efficiency of oxidation catalyst with alcohol blending which adds oxygen to the fuel. 2 DIESEL BIODIESEL BLEND Experimental: Commercial Diesel being sold in Faridabad, was used as reference fuel and for preparation of Diesel Biodiesel blends. For Biodiesel, Methyl ester of Jatropha Oil was prepared in the laboratory and the Biodiesel - Diesel blend of 5,10 and 20% referred as B5, B10 and B20 blends were prepared. Following fuels were taken up for the laboratory evaluation & for performance evaluation study in Diesel Indica cars i) Neat Diesel - Commercial fuel (Diesel) ii) Neat Diesel (95%) and Biodiesel (5%) blend referred as B5 iii) Neat Diesel (90%) and Biodiesel (10%) blend referred as B10 iv) Neat Diesel (80%) and Biodiesel (20%) blend referred as B20 Result & Discussions: Diesel and Bio-Diesel blends: The typical Physico-chemical data for base Diesel and Diesel - Biodiesel blends of B5,B10 and B20 are given in Table-3. As can be seen addition of biodiesel to diesel results in increase of following properties viz. Acidity,Density,Cetane, Viscosity and Flash point.the B5 blend meets the limit specified by BIS. However limits of IS specs for Diesel Biodiesel blends viz. B10 &B20 has not yet been specified. Fuel economy : It may be observed from Table-4 that with average steady speed fuel economy upto 40,000Km. with different blends of biodiesel, indicates that maximum fuel economy deterioration was -2.5% with B5 and -3.04% with B20. However, there is an marginal imrovement of 0.35% in fuel economy observed B10 Fuel. 3 HYDROGEN CNG BLEND: As a step towards ensuring energy security for the nation, our R&D Centre has launched several initiatives in Hydrogen study. IOC-R&D have been selected as the nodal agency for hydrogen research in the oil and gas sector. It commissioned India s first experimental

4 Hydrogen-CNG dispensing station in R&D campus at Faridabad. The Centre is now planning to set up India s first H-CNG dispensing station on a COCO retail outlet in Delhi by 2008 for fuelling the experimental vehicles running on H-CNG blended as well as on pure hydrogen. It is also collaborating with reputed international agencies for sharing knowledge on production, storage and transportation of Hydrogen. Presently Electrolyser based Hydrogen generation system (5 nm3/hr) has been commissioned at our premises for generation of hydrogen Emission studies with Hydrogen CNG Blend : One dedicated line from Hydrogen plant and another line from CNG Cylinders joins in a Blender unit where fixed volume of Hydrogen can be mixed The common line then joins in a Dispenser unit from where required Hydrogen CNG blend are delivered For conducting emission and fuel economy studies, three wheeler was selected. Emissions were determined by Horiba analyzer. Result & Discussions: It may be seen from Table-5 that with increase in Hydrogen conc. in the blend - CO, CO 2 and THC decreases where as NO X increases. Fuel economy is highest with CNG as such and decreases with increasing Hydrogen concentration because overall mass of CNG in the blends viz. 10% HCNG, 15% HCNG, 20% HCNG, 25% HCNG and 30% HCNG is decreasing respectively and accordingly less CNG is being available in the engine for ignition. CONCLUSION : In spite of steep increase in crude price i.e.around 95$ per barrel, world crude oil demand is set to increase 37% by 2030, driven largely by transportation needs Conventional Diesel and Gasoline Technologies for automotive fuel will still be major players for at least next Years Refineries have invested crores of rupees to upgrade the fuel quality of Gasoline and Diesel so as to meet Bharat stage III and Bharat stage IV specifications Various steps have been taken by Refineries to introduce clean fuel strategy Indian Oil Corporation was the first among oil companies in India to initiate studies in alternative fuels,viz. Ethanol-Gasoline blend, Diesel Biodiesel blend & H- CNG blend Growth in the Alternative fuels will be driven by environmental issues & its availability Based on the study conducted at R&D, Ethanol blended gasoline is already available in 13 states and two union terrirorities. (More states are likely to be covered in ) Using Diesel- Biodiesel blends, fuel economy deteiorates. However, there is an marginal imrovement of 0.35% in fuel economy observed with B10 Fuel. Studies conducted with H-CNG Blend in 3 wheeler reveals significant reduction in CO,CO 2 & THC emissions

5 TABLE - 1 PHYSICO-CHEMICAL CHARACTERISTICS OF ALCOHOL BLENDS No Properties Base 5% 10% IS : 2796 : 2000 Gasoline Ethanol blend Ethanol blend 1 Colour, Visual Orange Orange Orange Orange Copper strip corrosion for 3 Not more hrs at 50 C than No.1 No. 1 No.1 No.1 3 Density, at 15 C, Kg / m 3 4 Distillation Recovery up to 70 C (E 70), % by volume Recovery up to 100 C (E ), % by volume Recovery up to 180 C (E ),% by volume, min Final boiling point C, max Residue, Percent by volume, max Octane requirements : Research Octane Number, Min Or Anti-Knock Index, (RON+MON) / 2, Min 84-6 Existent gum., g / m 3, Max Potential gum, g/ m 3, Max Reid vapour pressure,(rvp) at 38 C, Kpa Vapour locking index (VLI), max Summer Other months

6 TABLE - 2 RESULTS OF MASS EMISSION AND FUEL ECONOMY USING ALCOHOL BLENDS HERO PUCH MOPED (WITH & W/O CAT.CONVERTER) CO THC FE (g/km) (g/km) (kpl) Gasoline % Ethanol % Ethanol PERCENTAGE REDUCTION IN MASS EMISSIONS AND FE CO THC FE (%) (%) (%) 5% Ethanol % Ethanol Note: Colour data indicates data generated in Hero Puch with cat. converter

7 S. No. TABLE-3 PHYSICO-CHEMICAL CHARACTERISTICS OF DIESEL & BIODIESEL BLENDS Properties Test method of IS: 1448 Limits as per IS : HSD HSD + 5 % Biodiesel JME Test Samples HSD+ 10 % Bio diesel JME HSD + 20 % Bio diesel JME 1. Acidity, Inorganic P : 2 Nil Nil Nil Nil Nil 2. Acidity, total, mg of KOH / gm, Max P : 2 To report Ash, % wt., Max P : < 0.01 < 0.01 < 0.01 < Carbon residue (Ramsbottom) on 10 % residue, % wt., Max P : Cetane Index, Min ASTM D- 6. Pour point deg. C, Max P : Copper strip corrosion for 3 hrs at 100 deg. C 8. Distillation % v/v recovered at 360 deg. C., Min.. 9. Flash point, deg. C, (Abel/ PMCC), Min. 10. K. V.,cSt at 40 deg C for winter C for summer P : 15 Not worse than No. 1 No.1 No.1 No.1 No.1 P : P : 20& P : to C 11. Density at 15 dec. C Kg/ m 3 P : to Water, % vol., Max P : Nil Nil Nil Nil

8 TABLE- 4 STEADY SPEED FUEL ECONOMY (KPL) WITH PASSENGER CARS USING BIODIESEL BLENDS Fuel /Fuel Blends Initial After Km After Km After Km After Km Average % change after 40000Km Neat diesel % BD Fuel % BD Fuel % BD Fuel TABLE-5 MASS EMISSION DATA WITH H-CNG BLENDS Fuel /Fuel Blends CO g/km THC g/km NOx g/km CO 2 g/km CNG % HCNG % HCNG % HCNG % HCNG % HCNG TABLE-6 FUEL ECONOMY OF VEHICLE WITH H-CNG BLENDS Fuel /Fuel Blends Mass Consmp. gm Distance Km Fuel Economy g/km CNG % HCNG % HCNG % HCNG % HCNG % HCNG