Modelling and Simulation of Biodiesel Blends Performance in Compression Ignition Engines

Modelling and Simulation of Biodiesel Blends Performance in Compression Ignition Engines

CHAPTER ONE

Aim and Objectives of the Research

The aim of this research is to model and simulate biodiesel blends performance in a compression ignition engine using GT Power software for environmental sanity and energy sustainability.

The specific objectives of this research are to:

produce biodiesel from Cotton, Jatropha, Neem oils and to analyse the composition using Gas Chromatography/Mass Spectroscopy (GC-MS)analyses;
blend the biodiesels produced from Cotton, Jatropha and Neem seed oil with petro- diesel, thereby forming binary blends and multi-blends of each biodiesel with petroleum diesel in different percentages and to examine the physico-chemical properties like specific gravity, viscosity, flash point, calorific value, sulphur content, B cetane number, acid value, copper strip corrosion, iodine value, and colour for each of these blends;
review the physico-chemical properties of different biodiesel feedstocks from literature and compute the mean of the physico-chemical properties of the biodiesels data sourced from the literature;
investigate the performance of the biodiesel and the blends in a stationary four- cylinder Compression Ignition engine at full load with variable speeds and to investigate exhaust gas emissions during the combustion of these blends in the CI engine, and
develop compression ignition engine model with the test rig’s specifications using GT Power software, use the primary data obtained to validate the modelled engine, and simulate the engines performances of the biodiesel multi-blends and biodiesels from the literature sources under full loading condition at variable

CHAPTER TWO

LITERATURE REVIEW

Relevant Literatures

Diesel fuel

Diesel fuel is a petroleum-based fuel for compression ignition engines. It is a viscous oily fuel that is obtained from the fractional distillation of crude petroleum oil. Diesel fuel has an ignition temperature of about 540⁰C and it is ignited by the heat of compression in compression ignition engines (EIA, 2013).

Nigerian diesel

Nigeria produces mainly sweet (Low sulphur) crude oil of which the cosmic mainstream is exported to the global market (EIA, 2013). Nigeria is the principal oil producer in Africa and was the world’s 4^th foremost exporter of liquefied natural gas (LNG) in 2012. The International Monetary Fund (IMF) reckons that oil and natural gas proceeds accounted for 96 % of entire export returns in 2012. It was estimated that in 2011, total principal energy utilization was about 4.3 quadrillion British Thermal Unit (EIA, 2016). According to EIA (2016), the Organization of Petroleum Exporting Countries (OPEC) unforeseen crude oil supply interruptions is approximately 2.3 million barrel per day (b/d) in June, 2016. The supply decreased with 0.3 million barrel per day (b/d) less in May, 2016 as a result of lower production from Nigeria, Libya, and Iraq. While Nigeria’s outcomes decreased in June 2016 (EIA, 2016). More decreases in Nigeria’s interruptions occurred in July 2016, as Royal Dutch Shell lifted a force majeure on exports of Bonny Light in early July, 2016, subsequent to the reinstatement of production into Bonny Terminal (EIA, 2016).

Nevertheless, Forcados and Brass River, Niger-Delta, which together account for roughly 0.3 million b/d of the disrupted volume, remain under force majeure. While some reinstatement of production is anticipated in the impending months, attacks on oil facilities remain, plus attacks aiming at wells, oil pipelines and three of Chevron’s manifolds in early July, 2016, (EIA, 2016).

Biodiesel

Biodiesel is presently the most promising source of renewable fuel with high potentials to replace petroleum derived diesel fuel, owing to similarities in physico-chemical properties between the diesel fuels and the biodiesel (Ghorbani et al., 2011). Bio-diesel can be defined as simple alkyl esters of fatty acids produced from vegetable oils and animal fats. Nigeria is blessed with many of such plants (Nafiu et al, 2011). According to Nigeria National Petroleum Corporation (NNPC) approved ethanol policy, bio-diesel shall represent fatty acid methyl ester or mono-alkyl esters originated from vegetable oil or animal fats for use in diesel engines, in line with quality specifications predetermined by the Standards Organization of Nigeria (SON), Department of Petroleum Resources (DPR) and any other dexterous governmental institute (Nigerian Bio-Fuel Policy and Incentives, 2011). One predilection is to develop biodiesel fuel and this has drawn more and more recognition (Haresh, 2008). In the United States, to a large degree, the impetus for the extension of biodiesel had come from soybean farmers who perceived it as a potential pioneering advert for soybean oil (EIA, 2013).

Advantages of biodiesel

Biodiesel fuels have so many advantages over petroleum diesel as readily established in the existing literature. The main advantages of biodiesel over regular diesel are: biodegradability, liquid nature, portability, low toxicity, availability, lower NOx except in leguminous feedstocks, emissions, environmentally friendly, better lubricating properties, higher flash point (safer to handle and store), can be used alone or blended with diesel, its blends extends the life span of CI engines, job creation, providing green cover to waste land, reduce dependency on imported refine oil, lower aromatic content, reduced urban migration, energy security, rural market expansion, higher cetane number improves ignition quality, reduced crime activities associated with petroleum exploration, calorific value is 9 % lower than petrol diesel, gives more complete combustion, thus, increasing the engine energy output, has no sulphur content, less flammable than petrol- diesel and burn at 50 ⁰C, loose viscosity- (gel ) at lower temperatures (Biswan et al., 2006; Akande and Olorunfemi, 2009; Belewu, 2011; Madarasz and Kumar, 2011; Izah and Ohimain, 2012; Simonyan and Fasina, 2013; Bugaje, 2014).

Disadvantages of biodiesel

The disadvantages of biodiesel include but not limited to: high production cost, reduced cold flow properties, detergent characteristics in fuel tank, higher viscosity, lower volatility and reactivity, higher flash point and fire point (producing carbon deposits), corrosive to rubber and liner materials, not storable in concrete lined tanks, the modification of fuel intake orifices to create higher cylinder pressure (Ghorbani et al., 2011; Izah and Ohimain, 2012; Idusayi et al., 2013).

The following challenges have been identified with biodiesel in the established literature: Competitions with food security and pharmaceutical demands on the feedstock, feedstock supply shortage, poor quality of the feedstock, processing challenges, technological challenges and poor policy framework (Izah and Ohimain, 2012).

CHAPTER THREE

MATERIALS AND METHODS

Materials and Equipment

Raw materials

The raw materials used for the purpose of this research are as follows: 1- Diesel fuel sourced from NNPC Mega Station, Katampe, Abuja Reagents: Methanol, Sodium hydroxide, sulphuric acid, phenolphthalein, distilled water

Vegetable oil samples comprising 5 litres each of Cotton seed oil and Jatropha seeds oil, they were sourced (From an extect made in the Lab) from Chemical Engineering Department, Ahmadu Bello University, Zaria, 5 litres of Neem seeds oil was sourced from Golden Star Mills, Kano, Nigeria.

Equipment

The following sets of equipment were used during the blending and experimentations/ testing of properties:

Measuring cylinder, 1litre maximum calibration produced by Goel Scientific Glass Works
Beakers: 1litre, 3litre and 5litre produced by Goel Scientific Glass Works iii- 50 ml burette, produced by Heta Glass Industries
Retort Stand Produced by Garg Process Glass India Private Limited v- 250 ml conical flask, produced by Heta Glass Industries

Stirrer
Stopped clock from i-phone 4 phone, Produced by Apple Inc. viii- 160 L Hair Thermocool double door Refrigerator
9ml, 15 ml and 20 ml test tubes and cork produced by Katyal Scientific Glass Works, Ambala Cantt, India

0to 110 ⁰C thermometer, manufactured by 110Ln. North Augusta, SC 29860 xi- Gas chromatography mass spectroscopy (GC-MS) machine, GCMS-QP2010 PLUS, Shimadzu, Japan, available in National Research Institute of Chemical Technology (NARICT), Zaria, Nigeria

Viscometer: Product-Koehler; Number 4 Viscometers; Size 150 (Equal Size); S/numbers: 1^st-1372; 2^nd-1379; 3^rd-1187 and 4^th-1189, available in Fuel Testing Laboratory, Kaduna Refining and Petrochemical Company, KRPC, NNPC, Kaduna, Nigeria

Bomb calorimeter, available in Fuel Testing Laboratory, Kaduna Refining and Petrochemical Company, KRPC, NNPC, Kaduna, Nigeria
Monochromatic Wavelength-Dispersive X-ray Fluorescence (MWDXRF) Spectrometry, available in Fuel Testing Laboratory, Kaduna Refining and Petrochemical Company, KRPC, NNPC, Kaduna, Nigeria
Fisher Brand Hydrometer (Size 0.795-0.910; Accuracy- 0.001), available inKaduna Refining and Petrochemical Company, Fuel Testing Laboratory, KRPC, NNPC, Kaduna, Nigeria

Portable Cetane/Octane metre, available at the Fuel Testing Laboratory., in Kaduna Refining and Petrochemical Company, KRPC, NNPC, Kaduna, Nigeria
Pensky Martens Closed Cup, Stanhope-Seta Product, available at the Fuel Testing Laboratory., in Kaduna Refining and Petrochemical Company,KRPC, NNPC, Kaduna, Nigeria

CHAPTER FOUR

RESULTS AND DISCUSSIONS

GC-MS Results

The results of methyl esters percentage contents of the biodiesel products were analysed by the Gas Chromatography – Mass Spectroscopy of the biodiesel; produced from Cotton, Jatropha and Neem oil are presented in Plates 4.1, 4.2 and 4.3 respectively and the interpretation of the peaks of the chromatogram was given after each figure, paying more attention to the methyl esters present in each chromatogram only.

CHAPTER FIVE

SUMMARY, CONCLUSION AND RECOMMENDATIONS

Summary

Biodiesel produces exceptional emissions properties and generates less greenhouse gases emissions. The following inferences were drawn out of the experimental findings aforementioned. The subsequent inferences were made from the discoveries of this work: 1- The calorific values of all the fuels and blends are above the ASTM minimum level and close to the heating values of fossil diesel, this makes them suitable for use in

CI engines operations. All fuel samples have flash points above ASTM minimum standards and 27 out of 28 are consistent with the ASTM standards both minimum and maximum, only the pure biodiesel from Neem (B100N) has a flash point slightly above the ASTM maximum level. Therefore, these fuels are safer to handle during storage or transportation because they cannot easily flash when exposed to flame or spark and hence they are recommended for use in the CI engines. All the 28 fuel samples are consistent with the ASTM standards for cetane number. They will have shortest possible ignition delay when they burn in the CI engines. Most of the viscosity values of the binary blends are consistent with the ASTM standard; the pour points of most of the fuel samples conformed with the ASTM standards. However, for the multi-blends, only a few is consistent with the ASTM limit. The specific gravity of the binary blends of cotton, Jatropha and Neem increases with the percentage increase of the biodiesel content in the blends. All the blends conform to the ASTM standards for specific gravity. The quality of atomisation, combustion, fuel droplets and air-fuel mixing can be improved in CI engines by using these blends. The acid values are very low and slightly lower than the ASTM maximum standards which are presumed to cause no harm on the fuel pumps and filters. All the 27 fuel samples and the pure diesel are consistent with the ASTM standards for total sulphur, copper strip and colour index except B100N for colour index.

From the secondary data obtained, the viscosity values for all the biodiesel from various feedstocks under review except the castor oil biodiesel conform to the ASTM standards, the kinematic viscosity of all the biodiesel fall within the ASTM standards except that of castor oil. The densities of all biodiesel from all feedstock except the algae conform to the ASTM and EN standards. The flash points of most biodiesel from various feedstocks fall within ASTM limits. The flash points of soy, safflower and corn biodiesel are slightly higher, while that of coconut, algae and tallow are slightly lower than the ASTM min. The heating values of all biodiesel except that of the castor confirm with EN minimum standards. All the specific gravity values except that the algae conform to ASTM minimum and maximum standards, most of the biodiesel values of pour point fall within ASTM limits except the palm and tallow biodiesel, with high positive values of 12.90 ⁰C and 10.86 ⁰C respectively. All the feedstock’s used in this review do not conform to the ASTM standards for sulphur content.
All the average cetane values under consideration conformed with the ASTM standards. There has been a substantial work in Nigeria with respect to policy issues especially as it relates to bio-energy the following incentives are clearly stated: Tax holidays, withholding tax on interest and dividends, waiver on imports, custom duties and value added tax and long term loan facilities. Hence Nigeria is a very good target for investors on biofuel crops, biodiesel refineries as well as blending plants for diesel/ biodiesel fuels.

The Jatropha 30 % blend B30J has the lowest exhaust temperature at 1500 rpm, 2000 rpm and 2500 rpm, while B25J has the lowest exhaust temperature at1000 rpm. The highest temperatures were recorded by B100J at 1000 rpm, 1500 rpm and 2000 rpm, followed by B15J at 2000 rpm, biodiesel blends of Jatropha especially B20J, B25J, and B30J have the tendencies of reducing overheating in CI engines, B25J, B30J and B555 have the poorest values of brake power. The best performances in terms of brake power were recorded by B10J, B20C B20J, and B30C. In terms of brake specific fuel consumption, the least value was generated by B30J, the Jatropha blend B5N is the overall best blend at most speeds while B25C has the highest specific fuel consumption. B20J has very low brake mean effective pressure at engine speed of 2000 rpm, while at maximum speed the highest value of brake mean effective pressure was generated by B30C. The lowest values of brake thermal efficiency were recorded by B25C at three different speeds and B222 at one speed.

All the binary and multi-blends including the pure biodiesel samples have very good values for combustion efficiencies. B25J gives the best combustion efficiencies. B20C, B15C and B20J have the lowest CO emissions followed by the pure biodiesels. All multi-blends except B555 are not too good in terms of CO Pure biodiesel samples and the 15 %, 20% and 25 % of binary blends of Cotton and Jatropha give the lowest NOx emissions and CO2 emissions. B20C has the highest SO2 emissions although within a negligible value. There is no significant difference on the excess air values of all the fuel samples.
Theengine performance simulation in GT-power confirms that the software is valid to be used in CI engine simulation with biodiesel from any feedstock and at all speeds. The highest bsfc was depicted by castor followed by coconut and then tallow, the highest bmep was observed during the simulation of the CI engine performance with sun flower, tallow, waste cooking oil and soy biodiesels in that order. The highest brake thermal efficiency values were given by soy, sun flower, palm and safflower respectively during the Cussons stationary 4-cylinder CI engine simulations with GT Power software.

Conclusion

The biodiesels produced from Cotton seed oil contained 89.75 % methyl-ester, the biodiesels produced from Jatropha contained 91.97 % methyl-ester, and the biodiesels produced from Neem contained 70.2 % methyl-ester. Therefore, Jatropha oil gives the best biodiesel in terms of percentage of methyl esters. Their dominant esters are methyl octadecanoate, methyl hexadecanoate and methyl pentadecanoate, hence, it could be inferred that, Cotton, Jatropha and Neem biodiesels are sustainable, renewable, reliable, combustible and suitable for use in compression ignitionengines
The fuel properties of biodiesels and mixed-blends with diesel mostly conform to the ASTM standards. The quality of atomisation, combustion, fuel droplets and air-fuel mixingcan be improved in CI engines using these blends Therefore, the profile of methyl esters in the biodiesel produced and the fuel properties indicate that they have the potential to refill the partial energy demands in an eco-friendly way and its likelihood to be a viable fuel source for CI engines
All the feedstocks reviewed conform to ASTM and EN Standards except: castor for viscosity and heating value; algae for density and specific gravity; and palm and tallow for pour
The25 % Jatropha blend (B25J) is the overall best blend for specific fuel consumption with least Nox emission; biodiesel produces exceptional emissions properties and generates less greenhouse gases emissions, and pure biodiesel samples, B15C, B25J and B20J give the lowest NOx and CO2
Compression ignition engine simulation in GT-power confirms that the software is suitable for simulation of biodiesel from any feedstock. The lowest bsfc was depicted by safflower followed by palm and the highest value was castor. The highest brake thermal efficiency values were given by soy, sun flower, palm ands afflower

Recommendations

Based on the established facts obtained from this thesis, the following recommendations are hereby made:

Further research should consider the simulation of biodiesel blends with oil additive and alcohols like butanol and ethanol in CIengines
Further research should be conducted to determine the particulate matter (PM) presentin the flue gases during fuel combustion
The GT-Suit Manufacturers should look at the possibility of adding biodiesel data to the software library

REFERENCES

Abbe, C. V. N., Nzengwa, R., Danwe, R., Ayissi, Z. M. Obounou. M. (2013). Simulation of a Direct Injection Diesel Engine Performance Fuelled on Biodiesel Using a Semi-Empirical 0D Model. Energy and Power Engineering. 5: 596-603
Abdulrahim, A. (2006). Quick Note Bio-energy Potential. Retrieved on 11^th September, 2012 from http://news. Mongabay. Com/bioenergy200608nigerias-biogas- potential-estimated-at
Adams, C. Peters, J. F. Schroer, B. J. and Ziemke, M. C. (1983). Investigation of Soybean Oil as a Diesel Fuel Extender: Endurance Test. Journal of the American Oil Chemists’ Society. 60(8): 1574-1579
Adebayo GB, Ameen OM, and Abbas LT (2011). Physicochemical properties of biodiesel produced from Jatropha curcas oil and fossil diesel. Journal of Microbiology Biotechnology Resource. 1(1): 12-16
Adejuwon, A. O., Olorunfemi, A. (2010). Synthetic Production of Amylase from Aspergillus Niger Isolated from Citrus Fruit. African Journal of Basic and Applied Sciences.2 (5-6). 158-160
Ahmad, F. Khan, A. U., and Yasa,. A. (2013). Transesterification of oil extracted from different species of algae for biodiesel production. African Journal of Environmental Science and Technology. 7(6): 358-364
Akande, S. O. Olarunfemi, A. (2009). Research and Development Potentials in Biofuels Production in Nigeria. African Research Review: An International Multi Dissiplinary Journal, Ethiopia, 3 (3): 34-45
Akindale, D. (2011). Biofuels for Green Transportation in Nigeria, Paper Presented at the ‘Summit on Energy and Sustainable Economic Growth, held at the Sheraton Hotel and Towers, Abuja, Nigeria’. 9-11 March
Albuquerque, M. C. G., Machado, Y. L., Torres, A. E. B., Azevedo, D. C. S., Cavalcante,
L. (2009). Firmiano LR, and Parente EJS. Properties of biodiesel oils formulated using different biomass sources and their blends. Renewable Energy. 34 (3): 857-859.
Ali, Y., Hanna, M . A., Cuppett, S. L. (1995). Fuel Properties of Tallow and Soybean Oil Esters. JAOCS. 72 (12): 1557-1564.
Alleman. T. L., Mc Cormick, R. L. (2006). Analysis of Coconut-Derived Biodiesel and Conventional Diesel Fuel Samples from the Philippines.NREL/MP. 540-38643
Allen, C . A. W., Watts, K. C., Ackman, R . G., Pegg M. J. (1999). Predicting the viscosity of biodiesel fuels from their fatty acid ester composition. Fuel. 78(11): 1319-1326
Alptekin E, and Canakci M. (2009). Characterization of the key fuel properties of methyl ester-diesel fuel blends. Fuel. 88(1), 75-80..

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