China
Africa
Explore chapters and articles related to this topic
Petrodiesel and Biodiesel Fuels for Marine Applications
Published in Ozcan Konur, Petrodiesel Fuels, 2021
Of the biofuels mentioned in Table 49.5, only the ‘marine distillate fuels’ are miscible with biodiesel, F-T diesel, renewable diesel, and upgraded biooil. Only biodiesel (at concentrations up to 7% vol.) is currently approved for use with MGO as a marine fuel, and studies by ExxonMobil, MARAD, and others have shown substantial reductions in PM when biodiesel is combined with MGO (Kass et al., 2018). PM reduction is an immediate environmental advantage of oxygenated fuels and can often be accomplished at relatively low levels of blend (< 10%). Since biooils cannot be mixed directly with distillates, any attempt to combine biooil with MGO would involve the use of surfactants to shape an emulsified fuel mixture. Emulsified fuels are vulnerable to separation over time, even though they exist as microemulsions, and thus usually have a poor shelf life. The effect of biooil-drained water on the combustion cycle is unknown. Nevertheless, the introduction of water to combustion is a proven approach to reducing emissions of PM and, in some situations, even emissions of NOx. The straight replacement of MGO with a biofuel demands that the amount of biofuel production be sufficiently high to fulfil consumption needs. It is uncertain whether the current production of biofuels will effectively displace MGO. Nevertheless, as blends, biofuels provide incentives for reducing both PM and CO2; and as demand for MGOs rises, biofuels may also provide an economic opportunity.
Impact analysis of emulsified Calophyllum oil biodiesel B100-WIC and B50-WIC on performance and emission characteristic of a diesel engine under variation in compression ratio
Published in International Journal of Ambient Energy, 2022
Rahul Krishnaji Bawane, A. Muthuraja, Gajanan N. Shelke, Chetan Choudhary
Nowadays, fuel emulsification has become the most attractive solution used to reduce the emission of NOx, particulate matter, smoke, and other pollutants (Debnath et al. 2014; Alahmer et al. 2010; Yahaya Khan et al. 2014). The emulsification of fuel improves the atomisation process and enhances combustion efficiency also, due to the micro-explosion phenomenon due to dispersed water into emulsified fuel help to better the performance of an engine. The emulsified fuel during combustion absorbs the heat of the combustion chamber at the time of water vaporisation, resulting reduction in the adiabatic flame temperature which leads to the reduction of a chemical reaction between the nitrogen and oxygen to form NOx. Water in fuel shows an increase in output power, this characteristic was reported due to an increase in expansion work and reduction in compression work as a result of the expansion of water vapours for emulsified test fuel.
Performance of a diesel engine with water emulsified diesel prepared with optimized process parameters
Published in International Journal of Green Energy, 2019
Neeraj Kumar, Hifjur Raheman, Rajendra Machavaram
Several investigators tried water injection method to resolve the issue of high peak combustion temperature and reported a reduction in NOx emission (Christensen and Johansson 1999; Tesfa et al. 2012). However, this method requires engine modification for injection of water in the combustion chamber and involves additional cost to use it in the normal engines. Subramanian (2011) conducted a comparative study to investigate the effect of emulsion and water injection method on the performance and emission level of engine. It was reported that water–diesel emulsion was more effective in improving brake thermal efficiency (BTE) along with a significant reduction in NO at higher load. Different types of blended fuels such as diesel-biodiesel blends (Pang et al. 2006), diesel-biodiesel-alcohol blend (Ren et al. 2008); diesel-oxygenate blends (Prakash, Singh, and Murugan 2013) and oil-biodiesel emulsion (Imdadul et al. 2016) have been successfully used in diesel engine and improvement in exhaust emissions were reported. The clean combustion with emulsified fuels also offered improvement in engine performance along with reduction of air pollutants (Nadeem et al. 2006). The presence of small amount of water in the emulsified fuel affected the physical and chemical kinetics of combustion (Alahmer 2013). In another study, Attia and Kulchitskiy (2014) found that emulsion with large size of water droplets reduced NOx emission more effectively. On the contrary, emulsion with fine droplets of water helped in lowering the smoke and unburned hydrocarbon of engine. Ithnin et al. (2014) conducted a study using water–diesel emulsion in the engine and reported that NOx and particulate matter (PM) in exhaust emission can be reduced simultaneously with water–diesel emulsion fuel. The vaporization of water droplets reduced the combustion temperature which resulted in NOx reduction with water emulsified diesel (Hasannuddin et al. 2016). Vellaiyan and Partheeban (2018) tried water emulsified soybean biodiesel in diesel engine and found that NOx and HC emissions reduced by 21.2 and 40%, respectively as compared to neat biodiesel when engine was run with emulsified biodiesel having 10% water. The emulsion of water with diesel and biodiesel is one of the cost effective technique to reduce the regulated pollutant emissions from engine (Ogunkoya et al. 2015; Saravanan, Anbarasu, and Gnanasekaran 2013).
Mitigation of harmful exhaust pollutants of DI diesel engine using emulsified fuel and hythane gas in a dual-fuel mode
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Radha Krishna Gopidesi, Premkartikkumar Sr, Vallapudi Dhana Raju
Generally, emulsified fuels are thermodynamically stable, fluid blends of polar and nonpolar liquids. It is splashed in the combustion chamber with an atomized form. In emulsion, water has a lower boiling point when contrasted with diesel. Because of this water droplet evaporates earlier than the diesel. The vaporization occurrence of water split up the oil layer and forms slighter oil droplets, which result in the enlarging of the oil’s surface to volume ratio. This stage is called “micro-explosion.” It causes the increase of the contact surface involving the atomized oil droplets and the air. This leads to a significant enhancement of the flame propagation and thermal efficiency of the fuel. Dao Nam Cao et al. (2020) investigated the combination of fuel injection under high pressure applied to PCCI combustion mode, it was assessed on the basis of the emission characteristics of NOx and PM. The diesel engine has played a major role in modern human life in various sectors of applications such as electrical, construction, and automotive industries according to Bora et al. (2014). However, frequent increasing environmental pollutants from diesel engines lead to stringent pollution norms. The formation of NOX emission is high in diesel fuel combustion engines with the effect of peak combustion temperature. According to prior research work and survey, it found that emulsion fuel is the most effective and efficient fuel to control the emissions of Particulate Matter (PM) and NOX. On the other hand, the existence of water in the emulsion fuel leads to a slight reduction of the calorific value of the fuel. It shows the lower thermal efficiency when contrasted with diesel fuel. However, the prior study found that the emulsified dual fuel technique affords better performance with a promising reduction of emissions. Several research works were carried out on the emulsified dual-fuel technique with various gases like Hydrogen, Natural Gas (NG), Compressed Natural Gas (CNG), Methane, Producer Gas and Biogases, etc. Bora and Saha (2015) worked on a four-stroke, single-cylinder, DI, water-cooled, 3.5 kW VCR diesel engine powered with biogas and emulsified rice bran oil biodiesel. They conducted the exergy analysis for the given data and found that 32.47% of the fuel energy was recuperated in the form of available energy (exergy). Moreover, they observed an increase in shaft availability with the enhanced CR and IT. On the other hand, it showed the decline of exhaust gas availability, exergy demolition, and entropy making.