Search Results (28)

Issues such as rising fuel prices, fuel costs, and lowering reserves highlight the importance of research into sustainable fuels derived from biological sources. This study is focused on experiments on a CI engine using ethanol and propanol-based ternary blends. Palm biodiesel is kept constant at 40% volumetric concentration, while diesel and ethanol/propanol are varied in different batches. The results obtained with ternary blends were compared with reference fuel diesel, pure palm biodiesel, and a palm biodiesel–diesel binary blend. The ternary blends exhibit lower brake thermal efficiency and higher brake specific energy consumption than diesel and binary blends due to their lower calorific value. Despite in-fuel oxygen presence, lower brake specific oxides of nitrogen and smoke opacity were observed for engine operation with a ternary blend due to the predominant role of higher latent heat of vaporization and volatility of alcohols, but unburned hydrocarbon and carbon monoxide emissions increased due to the interactive effect of a lower cetane number, higher latent heat of vaporization, and lower kinematic viscosity of alcohols when compared to reference fuels. Among the tested fuels, in-cylinder pressure was observed to decrease with ternary blends due to their lower calorific value, but a raised heat release rate was attributed to lower viscosity and faster burning of alcohols. Full article

Diesel engines are one of the most popular reciprocating engines on the market today owing to their great thermal efficiency and dependability in energy conversion. Growing concerns about the depletion of fossil resources, fluctuating prices in the market, and environmental issues have prompted the search for renewable fuels with higher efficiencies compared with conventional fuels. Fuel derived from vegetable oils and animal fats has comparable characteristics to diesel fuel, but is renewable, despite being manufactured from various feedstocks. Nevertheless, the direct use of these fuels is strictly prohibited because it will result in many issues in the engine, affecting engine performance and durability, as well as emissions. To make biofuels as efficient as fossil fuels, it is essential to alter their characteristics. The use of emulsification techniques to obtain emulsified biofuels is one of the many ways to modify the fuel characteristics. Emulsification techniques allow for a decrease in viscosity and an increase in atomisation during injection. To date, emulsification techniques have been studied less thoroughly for use with vegetable oils and animal fats. This article will discuss the preparation and characterisation of emulsified biofuels made from vegetable oils and animal fats. This current paper reviewed research studies carried out on different emulsification techniques for biofuels used in diesel engines. Full article

Most of the world’s energy requirements are still derived from natural resources. This will result in a catastrophic energy crisis with negative environmental consequences. The increased energy supply will result in greater consumption of non-renewable sources. The production of biomass producer gas (BPG) from biomass gasification has received significant attention as an alternative fuel due to the depletion of non-renewable resources. This experimental study aimed to determine the flame propagation, flame propagation speed, and chamber pressure trace of BPG at different equivalence ratios. Understanding the characteristics of the BPG’s combustion, finding lower greenhouse gas emissions of BPG, and minimizing the use of fossil fuels is necessary to mitigate these problems. Using the direct visualization technique, an optical constant volume combustion chamber (CVCC) was developed to measure combustion characteristics. Liquid petroleum gas (LPG) was used to compare the flame propagation speed in the CVCC calibration. In comparison to wood pellet (WP), coconut husk (CH), and palm kernel shell (PKS), the chamber peak pressure at ϕ equal to 1 of CH for the combustion of BPG was the lowest at 20.84 bar. At ϕ of 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, and 1.3, the chamber peak pressure of CH was discovered to be around 17.77, 18.12, 18.81, 20.84, 20.39, 17.25, and 16.37 bar, respectively. Compared to the other two types of BPG, CH produced the lowest emissions of CO₂ and CO at 2.03% and 0.022%, respectively. In conclusion, the CH had the lowest chamber peak pressure and emissions due to the lower heating value (LHV) being relatively lower. Full article

An effective analytical technique for biomass characterisation is inevitable for biomass utilisation in energy production. To improve biomass processing, various thermal conversion methods such as torrefaction, pyrolysis, combustion, hydrothermal liquefaction, and gasification have been widely used to improve biomass processing. Thermogravimetric analysers (TG) and gas chromatography (GC) are among the most fundamental analytical techniques utilised in biomass thermal analysis. Thus, GC and TG, in combination with MS, FTIR, or two-dimensional analysis, were used to examine the key parameters of biomass feedstock and increase the productivity of energy crops. We can also determine the optimal ratio for combining two separate biomass or coals during co-pyrolysis and co-gasification to achieve the best synergetic relationship. This review discusses thermochemical conversion processes such as torrefaction, combustion, hydrothermal liquefaction, pyrolysis, and gasification. Then, the thermochemical conversion of biomass using TG and GC is discussed in detail. The usual emphasis on the various applications of biomass or bacteria is also discussed in the comparison of the TG and GC. Finally, this study investigates the application of technologies for analysing the composition and developed gas from the thermochemical processing of biomass feedstocks. Full article

Two main aspects of the transportation industry are pollution to the environment and depletion of fossil fuels. In the transportation industry, the pollution to the environment can be reduced with the use of cleaner fuel, such as gas-to-liquid fuel, to reduce the exhaust emissions from engines. However, the depletion of fossil fuels is still significant. Biodiesel is a non-toxic, renewable, and biodegradable fuel that is considered an alternative resource to conventional diesel fuel. Even though biodiesel shows advantages as a renewable source, there are still minor drawbacks while operating in diesel engines. Modern vehicle engines are designed to be powered by conventional diesel fuel or gasoline fuel. In this review, the performance, emissions, combustion, and endurance characteristics of different types of diesel engines with various conditions are assessed with biodiesel and blended fuel as well as the effect of biodiesel on the diesel engines. The results show that biodiesel and blended fuel had fewer emissions of CO, HC, and PM but higher NOx emissions than the diesel-fuelled engine. In the endurance test, biodiesel and blended fuel showed less wear and carbon deposits. A high concentration of wear debris was found inside the lubricating oil while the engine operated with biodiesel and blends. The performance, emissions, and combustion characteristics of biodiesel and its blends showed that it can be used in a diesel engine. However, further research on long-term endurance tests is required to obtain a better understanding of endurance characteristics about engine wear of the diesel engine using biodiesel and its blends. Full article

Homogeneous charge compression ignition (HCCI) is considered an advanced combustion method for internal combustion engines that offers simultaneous reductions in oxides of nitrogen (NO_x) emissions and increased fuel efficiency. The present study examines the influence of intake air temperature (IAT) and premixed diesel fuel on fuel self-ignition characteristics in a light-duty compression ignition engine. Partial HCCI was achieved by port injection of the diesel fuel through air-assisted injection while sustaining direct diesel fuel injection into the cylinder for initiating combustion. The self-ignition of diesel fuel under such a set-up was studied with variations in premixed ratios (0–0.60) and inlet temperatures (40–100 °C) under a constant 1600 rpm engine speed with 20 Nm load. Variations in performance, emissions and combustion characteristics with premixed fuel and inlet air heating were analysed in comparison with those recorded without. Heat release rate profiles determined from recorded in-cylinder pressure depicted evident multiple-stage ignitions (up to three-stage ignition in several cases) in this study. Compared with the premixed ratio, the inlet air temperature had a greater effect on low-temperature reaction and HCCI combustion timing. Nonetheless, an increase in the premixed ratio was found to be influential in reducing nitric oxides emissions. Full article

In this study, the effect of a thermal barrier coating with yttria-stabilized zirconia (YSZ) and aluminum silicate (Al₂O₃·SiO₂) alongside an NiCrAl bond coat on the engine performance and emission analysis was evaluated by using conventional diesel and pure palm oil biodiesel. These materials were coated on the piston alloy via plasma spray coating. The findings demonstrated that YSZ coating presented better engine performances, in terms of brake thermal efficiency (BTE) and brake-specific fuel consumption (BSFC) for both fuels. The piston with YSZ coating materials achieved the highest BTE (15.94% for diesel, 14.55% for biodiesel) and lowest BSFC (498.96 g/kWh for diesel, 619.81 g/kWh for biodiesel). However, Al₂O₃·SiO₂ coatings indicated better emission with lowest emissions of NO, CO, and CO₂ for both diesel and biodiesel. For the uncoated piston, the results indicated that the engine clocked the highest torque and power, especially on diesel fuel due to the high viscosity and low caloric value, and it recorded the lowest hydrocarbon emission due to the complete combustion of fuel in the engine. Hence, it was concluded that the YSZ coating could lead to better engine performance, while Al₂O₃·SiO₂ showed promising results in terms of greenhouse gas emission. Full article

One of the greatest challenges of the 21st century is to fulfill the growing energy needs sustainably and cost-effectively. Among the different sources of energy, biodiesel is one of the alternative energy sources that has tremendous potential to become a major mainstream renewable energy mix. Jatropha is an important raw input for biodiesel that provides an ecological and sustainable solution for emerging greenhouse gas emissions over the other biomass feedstock. This paper critically evaluates different factors and presents a SWOT analysis (strengths, weaknesses, opportunities, and threats) and barriers to the adoption of Jatropha biodiesel. In Pakistan, the estimated production of Jatropha biodiesel is expected to be 2.93 million tons, that are calculated from available barren land and possible shortlisted suitable areas for Jatropha plantation. It is ~25% of the total import (11.84 million tons) of petroleum products, which can save ~$2 billion USD reserves of Pakistan. The cultivation of Jatropha on barren land is an environmentally and economically lucrative approach for Pakistan. This study has real implications for developing a policy framework related to the environment and socio-economic feasibility of Jatropha biodiesel production in Pakistan. Full article

This study investigated the tribological behaviour of Pongamia oil (PO) and 15W–40 mineral engine oil (MO) with and without the addition of graphene nanoplatelets (GNPs). The friction and wear characteristics were evaluated in four-ball anti-wear tests according to the ASTM D4172 standard. The morphology of worn surfaces and the lubrication mechanism of GNPs were investigated via SEM and EDS. This study also focuses on the tribological effect of GNP concentration at various concentrations. The addition of 0.05 wt % GNPs in PO and MO exhibits the lowest friction and wear with 17.5% and 12.24% friction reduction, respectively, and 11.96% and 5.14% wear reduction, respectively. Through SEM and EDS surface analysis, the surface enhancement on the worn surface by the polishing effect of GNPs was confirmed. The deposition of GNPs on the friction surface and the formation of a protective film prevent the interacting surfaces from rubbing, resulting in friction and wear reduction. Full article

In this study, the performance and emission of a thermal barrier coating (TBC) engine which applied palm oil biodiesel and diesel as a fuel were evaluated. TBC was prepared by using a series of mixture consisting different blend ratio of yttria stabilized zirconia (Y₂O₃·ZrO₂) and aluminum oxide-silicon oxide (Al₂O₃·SiO₂) via plasma spray coating technique. The experimental results showed that mixture of TBC with 60% Y₂O₃·ZrO₂ + 40% Al₂O₃·SiO₂ had an excellent nitrogen oxide (NO), carbon monoxide (CO), carbon dioxide (CO₂), and unburned hydrocarbon (HC) reductions compared to other blend-coated pistons. The finding also indicated that coating mixture 50% Y₂O₃·ZrO₂ + 50% Al₂O₃·SiO₂ had the highest brake thermal efficiency (BTE) and lowest of brake specific fuel consumption (BSFC) compared to all mixture coating. Reductions of HC and CO emissions were also recorded for 60% Y₂O₃·ZrO₂ + 40% Al₂O₃·SiO₂ and 50% Y₂O₃·ZrO₂ + 50% Al₂O₃·SiO₂ coatings. These encouraging findings had further proven the significance of TBC in enhancing the engine performance and emission reductions operated with different types of fuel. Full article

Biodiesel has gained popularity in diesel engines as a result of the rapid decline of fossil fuels and population growth. The processing of biodiesel from non-edible Moringa Oleifera was investigated using a single-step transesterification technique. Both fuels had their key physicochemical properties measured and investigated. In a common-rail diesel engine, the effects of MB50 fuel blend on the symmetric characteristics of engine-out responses were evaluated under five load settings and at 1000 rpm. As compared to standard diesel, MB50 increased brake thermal efficiency (BTE), and nitrogen oxides (NO_x) emissions while lowering brake specific fuel consumption (BSFC), and smoke emissions for all engine loads. A further study of injection pressure and start of injection (SOI) timing for MB50 fuel was optimized using response surface methodology (RSM). The RSM optimization resulted in improved combustion dynamics due to symmetry operating parameters, resulting in a simultaneous decrease in NO_x and smoke emissions without sacrificing BTE. RSM is an efficient optimization method for achieving optimal fuel injection parameter settings, as can be deduced. As a result, a clearer understanding of the use of MB50 fuel in diesel engines can be given, allowing for the best possible engine efficiency. Full article

As non-renewable conventional fossil fuel sources are depleting day by day, researchers are continually finding new ways of producing and utilizing alternative, renewable, and reliable fuels. Due to conventional technologies, the environment has been degraded seriously, which profoundly impacts life on earth. To reduce the emissions caused by running the compression ignition engines, waste cooking oil (WCO) biodiesel is one of the best alternative fuels locally available in all parts of the world. Different study results are reviewed with a clear focus on combustion, performance, and emission characteristics, and the impact on engine durability. Moreover, the environmental and economic impacts are also reviewed in this study. When determining the combustion characteristics of WCO biodiesel, the cylinder peak pressure value increases and the heat release rate and ignition delay period decreases. In performance characteristics, brake-specific fuel consumption increases while brake-specific energy consumption, brake power, and torque decrease. WCO biodiesel cuts down the emissions value by 85% due to decreased hydrocarbon, SO₂, CO, and smoke emissions in the exhaust that will effectively save the environment. However, CO₂ and NO_x generally increase when compared to diesel. The overall economic impact of production on the utilization of this resource is also elaborated. The results show that the use of WCO biodiesel is technically, economically, environmentally, and tribologically appropriate for any diesel engine. Full article

The objective of this paper is to study the effect of coconut oil biodiesel (COB)-diesel blends on exhaust particulate matter (PM) emissions and fuel injection responses in an unmodified turbocharged four-stroke common-rail direct injection (CRDI) diesel engine. Characterization of COB and their blends has been conducted to ascertain the applicability of these fuels for the existing engine. The test fuels used were fossil diesel fuel, COB10, COB20, COB30 and COB50 of biodiesel-diesel fuels. A test cycle which composed of 16 different steady-state modes at various loads and speed conditions was followed. Generally, the results showed a marginally advanced SOI timing and longer injection duration with increasing COB blends at higher load as compared to diesel fuel. Additionally, the lower calorific value (CV) and higher viscosity of the COB fuel blends have resulted in reduced turbo boost pressure and increased common-rail fuel injection pressure, respectively, across all engine speeds and loads. On the aspects of PM emissions characterization, results indicated that the blending of COB with conventional diesel had benefits over diesel in PM reduction. In fact, the largest achievable PM mass reduction of 38.55% was attained with COB50. In addition, it was noticed that the size of PM particles accumulated such that the granular size increased with higher diesel content in the blend. Additionally, the composition analysis on the PM collected by EDX spectroscopy has revealed that the C, O and Si as three main elements that made up the PM particles in descending order. Overall, the results indicated that COB biodiesel is a clean-burning alternative fuel and can be used satisfactorily in an unmodified diesel engine without the needs for engine remapping. Full article

Pakistan is among the countries that have already crossed the water scarcity line, and the situation is worsened due to the recent pandemic. This is because the major budget of the country is shifted to primary healthcare activities from other development projects that included water treatment and transportation infrastructure. Consequently, water-borne diseases have increased drastically in the past few months. Therefore, there is a dire need to address this issue on a priority basis to ameliorate the worsening situation. One possible solution is to shift the focus/load from mega-projects that require a plethora of resources, money, and time to small domestic-scale systems for water treatment. For this purpose, domestic-scale solar stills are designed, fabricated, and tested in one of the harshest climatic condition areas of Pakistan, Rahim Yar Khan. A comprehensive overview of the regional climatology, including wind speed, solar potential, and ambient temperature is presented for the whole year. The analysis shows that the proposed system can adequately resolve the drinking water problems of deprived areas of Pakistan. The average water productivity of 1.5 L/d/m² is achieved with a total investment of PKR 3000 (<$20). This real site testing data will serve as a guideline for similar system design in other arid areas globally. Full article

It has been widely accepted worldwide, that the greenhouse effect is by far the most challenging threat in the new century. Renewable energy has been adopted to prevent excessive greenhouse effects, and to enhance sustainable development. Malaysia has a large amount of biomass residue, which provides the country with the much needed support the foreseeable future. This investigation aims to analyze potentials biomass gases from major biomass residues in Malaysia. The potential biomass gasses can be obtained using biomass conversion technologies, including biological and thermo-chemical technologies. The thermo-chemical conversion technology includes four major biomass conversion technologies such as gasification, combustion, pyrolysis, and liquefaction. Biomass wastes can be attained through solid biomass technologies to obtain syngas which includes carbon monoxide, carbon dioxide, oxygen, hydrogen, and nitrogen. The formation of tar occurs during the main of biomass conversion reaction such as gasification and pyrolysis. The formation of tar hinders equipment or infrastructure from catalytic aspects, which will be applied to prevent the formation of tar. The emission, combustion, and produced gas reactions were investigated. It will help to contribute the potential challenges and strategies, due to sustainable biomass, to harness resources management systems in Malaysia to reduce the problem of biomass residues and waste. Full article