Effect of electrostatic precipitator on exhaust emissions in biodiesel fuelled CI engine

Environmental Science and Pollution Research - The exhaust emissions from the compression ignition engines are harmful to both human beings and the environment. After-treatment devices placed in...     

Effect of induction hydroxy and hydrogen along with algal biodiesel blend in a CI engine: a comparison of performance and emission characteristics

Environmental Science and Pollution Research - Gaseous fuel as a combustion enhancer with a pilot fuel offers significant benefits in improving engine efficiency. Hydrogen and hydroxy are the two...     

Effect of start of main injection timing on performance,emission, and combustion characteristics of a VGT CI engine fueled with neem biodiesel

The performance of engine parameters is more influenced with fuel injection strategies namely start of main injection timing (SoMI). An experimental analysis was performed to find the optimum SoMI timing based on performance, emission, and combustion characteristics. Base fuel of diesel and neem biodiesel was used as test fuels. The neem biodiesel was prepared by esterification and transesterification process. It is found from literature that neem biodiesel blend NB20 with diesel gives optimum performance and emission characteristics; therefore, NB20 blend was used for experiments. A variable geometry turbocharger (VGT) compression ignition (CI) engine was used to conduct the experiments. Engine performance parameters were estimated and compared with a base fuel of diesel and with NB20 blends. In this experimentation, fuel injection pressure (FIP) of 800 bar and engine speed of 1700 rpm were considered. SoMI timing was varied from 2° to 10° bTDC with an increment of 2° bTDC timing. Cylinder pressure (CP) and heat release rate (HRR) were estimated and found that are higher for diesel fuel compared to NB20 blend at different SoMI timings. The addition of neem biodiesel NB20 blend to diesel fuel decreases the exhaust emissions except NOx emissions. The BSFC was considerably reduced and BTE was improved almost equivalent to the diesel fuel for NB20. From the results, it is concluded that 10° bTDC SoMI timing provides 13% improvement in BTE, 21% decrement in BSFC, and 7.5% reduction in CO₂ emissions.

     

Effects of ethanol as an additive on odor detection thresholds of Alaskan gasolines at sub-arctic temperatures

This study evaluated the odor thresholds of two Alaskan unleaded gasolines, Tesoro and Mapco, and their ethanol oxyfuel blends at typical winter temperatures of −25°F, O°F, and +25°F. We found that temperature had a slight but variable effect on both odor thresholds and headspace composition. When 10% ethanol was added to Tesoro, a refined gasoline, there was a significant lowering (83%) of the odor detection threshold, i.e., an increase in human sensitivity to the odor. Vapors formulated from 10% ethanol-Mapco gasoline mixtures did not change the odor detection threshold. This study supports the hypothesis that the base gasolines interact variably with oxygenate additives. Ethanol appears to behave in a dissimilar manner when added to gasolines with different aromatic content.     

Effect of SME biodiesel blends on PM2.5 emission from a heavy-duty engine

To explore the effect of biodiesel and sulfur content on PM_2.5 emissions, engine dynamometer tests were performed on a Euro II engine to compare the PM_2.5 emissions from four fuels: two petroleum diesel fuels with sulfur contents of 50 and 100 ppm respectively, and two B20 fuels in which soy methyl ester (SME) biodiesel was added to each of the above mentioned petroleum diesel fuels (v/v: 80%/20% for petroleum diesel and SME respectively). Gaseous pollutants and PM_2.5 emissions were sampled with an AVL AMA4000 and Model 130 High-Flow Impactor (MSP Corp). Measurements were made of the PM_2.5 mass, organic carbon (OC), elemental carbon (EC) and the water-soluble ion distribution. The results showed that PM_2.5 emissions decreased with lower sulfur content or blending with SME biodiesel, and the decrease would be more by applying both two methods together. Particles of approximately 0.13 μm contributed 48–83% of PM_2.5 emissions. The impact of sulfur content on this percentage was different for low and high engine speed. The majority of PM_2.5 was comprised of OC and EC, and the carbon emission rate had the same trend as PM_2.5. Since the EC abatement of B20 was larger than OC, the OC/EC ratio of B20 was always larger than that of petroleum diesel. For petroleum diesel, the OC/EC increased with sulfur content, which was not the case for B20. The SO₄^2? had highest emission rate in the water-soluble ions of PM.     

Emission analysis on the effect of nanoparticles on neat biodiesel in unmodified diesel engine

Environmental Science and Pollution Research - Biodiesels derived from the mahua seeds are established as a promising alternative for the diesel fuel owing to its non-edible nature and improved...     

An experimental study on usage of plastic oil and B20 algae biodiesel blend as substitute fuel to diesel engine

Usage of plastics has been ever increasing and now poses a tremendous threat to the environment. Millions of tons of plastics are produced annually worldwide, and the waste products have become a common feature at overflowing bins and landfills. The process of converting waste plastic into value-added fuels finds a feasible solution for recycling of plastics. Thus, two universal problems such as problems of waste plastic management and problems of fuel shortage are being tackled simultaneously. Converting waste plastics into fuel holds great promise for both the environmental and economic scenarios. In order to carry out the study on plastic wastes, the pyrolysis process was used. Pyrolysis runs without oxygen and in high temperature of about 250–300 °C. The fuel obtained from plastics is blended with B20 algae oil, which is a biodiesel obtained from microalgae. For conducting the various experiments, a 10-HP single-cylinder four-stroke direct-injection water-cooled diesel engine is employed. The engine is made to run at 1500 rpm and the load is varied gradually from 0 to 100 %. The performance, emission and combustion characteristics are observed. The BTE was observed to be higher with respect to diesel for plastic-biodiesel blend and biodiesel blend by 15.7 and 12.9 %, respectively, at full load. For plastic-biodiesel blend, the emission of UBHC and CO decreases with a slight increase in NO _x as compared to diesel. It reveals that fuel properties are comparable with petroleum products. Also, the process of converting plastic waste to fuel has now turned the problems into an opportunity to make wealth from waste.     

无铅汽油添加剂甲基叔丁基醚(MTBE)的环境化学行为及其分析方法

本文简要介绍了无铅汽油添加剂MTBE的物理化学性质、环境化学行为、地下水的污染状况和对动物的潜在致癌毒理 ,并对其分析方法作了综述 ,指出了我国开展MTBE有关研究的重要性。     

Combustion,performance, and emission characteristics of diesel engine using oxyhydrogen gas as a fuel additive

Environmental Science and Pollution Research - A lot of research is being carried out to reduce the environmental pollution resulting from compression ignition engines. For this, various gaseous...     

Effect Of n-amyl alcohol/biodiesel blended nano additives on the performance,combustion and emission characteristics of CRDi diesel engine

Environmental Science and Pollution Research - This paper deals with the study on the influence of the effects of iron oxide nanoparticle additives when added to ternary fuel (diesel + mahua methyl...     

Effects of biodiesel on emissions of regulated air pollutants and polycyclic aromatic hydrocarbons under engine durability testing

An 80,000-km durability test was performed on two engines using diesel and biodiesel (methyl ester of waste cooking oil) as fuel in order to examine emissions resulting from the use of biodiesel. The test biodiesel (B20) was blended with 80% diesel and 20% methyl ester derived from waste cooking oil. Emissions of regulated air pollutants, including CO, HC, NO_x, particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) were measured at 20,000-km intervals. The identical-model engines were installed on a standard dynamometer equipped with a dilution tunnel used to measure the pollutants. To simulate real-world driving conditions, emission measurements were made in accordance with the United States Environmental Protection Agency (USEPA) FTP transient cycle guidelines. At 0 km of the durability test, HC, CO and PM emission levels were lower for the B20 engine than those for diesel. After running for 20,000 km and longer, they were higher. However, the deterioration coefficients for these regulated air pollutants were not statistically higher than 1.0, implying that the emission factors do not increase significantly after 80,000 km of driving. Total (gaseous+particulate phase) PAH emission levels for both B20 and diesel decreased as the driving mileage accumulated. However, for the engine using B20 fuel, particulate PAH emissions increased as engine mileage increased. The average total PAH emission factors were 1097 and 1437 μg bhp h⁻¹ for B20 and diesel, respectively. For B20, the benzo[a]pyrene equivalence emission factors were 0.77, 0.24, 0.20, 7.48, 5.43 and 14.1 μg bhp h⁻¹ for 2-, 3-, 4-, 5-, 6-ringed and total PAHs. Results show that B20 use can reduce both PAH emission and its corresponding carcinogenic potency.     

Experimental investigation on use of hydrotreated Simarouba oil (green diesel) and hydrogen gas in a dual-fuel CI engine

Environmental Science and Pollution Research - Hydrogen additives to Simarouba glauca vegetable oil (SO) are a common method for addressing the difficulties in combustion caused by SO’s poor...     

Characteristics of trans,trans-2,4-decadienal and polycyclic aromatic hydrocarbons in exhaust of diesel engine fueled with biodiesel

The use of biodiesel fuel as a substitute for fossil fuel in diesel engines has received increasing attention in recent years. This study is the first to investigate and compare the characteristics of mutagenic species, trans,trans-2,4-decadienal (tt-DDE), and polycyclic aromatic hydrocarbons (PAHs) in the diluted exhaust of diesel engines operated with diesel and biodiesel blend fuels. An engine of current design was operated on a dynamometer consistent with the US federal test procedure transient-cycle specifications. Petroleum diesel and a blend of petroleum diesel and biodiesel (B20) were tested. Exhaust sampling was carried out on diluted exhaust in a dilution tunnel with a constant-volume sampling system. Concentrations of tt-DDE and PAHs were analyzed by GC/MS. Although average PAH emission factors decreased from 1403 to 1051 μg bhp-h⁻¹, the results show that tt-DDE is evidently generated (1.28 μg bhp-h⁻¹) in the exhaust of diesel engine using B20 as fuel. This finding suggests that tt-DDE emission from the use of biodiesel should be taken into account in characterization and health-risk assessment. The results also show that tt-DDE is depleted in the diesel engine combustion process and the existence of tt-DDE in biodiesel is the major source of tt-DDE emission. The distribution of tt-DDE in the particulate phase is 55.3% under this study's sampling conditions. For diesel and B20, PAH phase distributions have similar trends. Lower molecular weight PAHs predominate in gaseous phase for both diesel and B20. Cold-start driving has higher tt-DDE and PAH emission factors, as well as a higher percentage of tt-DDE in particulate phase, than for warm-start driving.     

Emission profile of 18 carbonyl compounds,CO, CO2, and NOx emitted by a diesel engine fuelled with diesel and ternary blends containing diesel,ethanol and biodiesel or vegetable oils

The impact of vehicular emissions on air depends, among other factors, on the composition of fuel and the technology used to build the engines. The reduction of vehicular emissions requires changes in the fuel composition, and improving the technologies used in the manufacturing of engines and for the after-treatment of gases. In general, improvements to diesel engines have targeted not only emission reductions, but also reductions in fuel consumption. However, changes in the fuel composition have been shown to be a more rapid and effective alternative to reduce pollution. Some factors should been taken into consideration when searching for an alternative fuel to be used in diesel engines, such as emissions, fuel stability, availability and its distribution, as well as its effects on the engine durability. In this work, 45 fuel blends were prepared and their stability was evaluated. The following mixtures (v/v/v) were stable for the 90-day period and were used in the emission study: diesel/ethanol – 90/10%, diesel/ethanol/soybean biodiesel – 80/15/5%, diesel/ethanol/castor biodiesel – 80/15/5%, diesel/ethanol/residual biodiesel – 80/15/5%, diesel/ethanol/soybean oil – 90/7/3%, and diesel/ethanol/castor oil – 90/7/3%. The diesel/ethanol fuel showed higher reduction of NO_x emission at a lower load (2 kW) when compared with pure diesel. The other fuels showed a decrease of NO_x emissions in the ranges of 6.9–75% and 4–85% at 1800 rpm and 2000 rpm, respectively. The combustion efficiencies of the diesel can be enhanced by the addition of the oxygenate fuels, like ethanol and biodiesel/vegetable oil, resulting in a more complete combustion in terms of NO_x emission. In the case of CO₂ the decreases were in the ranges of 5–24% and 4–6% at 1800 rpm and 2000 rpm, respectively. Meanwhile, no differences were observed in CO emission. The carbonyl compounds (CC) studied were formaldehyde, acetaldehyde, propionaldehyde, acrolein, acetone, crotonaldehyde, butyraldehyde, butanone, benzaldehyde, isovaleraldehyde, valeraldehyde, o-toluenaldehyde, m-toluenaldehyde, p-toluenaldehyde, hexaldehyde, octaldehyde, 2,5-dimethylbenzaldehyde, and decaldehyde. Among them, formaldehyde, acetaldehyde, acetone, and propionaldehyde showed the highest emission concentrations. When ternary blend contains vegetable oil, there is a strong tendency to increase the emissions of the high weight CC and decrease the emissions of the low weight CC. The highest concentration of acrolein was observed when the fuel contains diesel, ethanol and biodiesel. With the exception of NO_x, the use of ternary blended fuels resulted on the increase in the emission rates of the studied compounds.     

用后处理装置减少DMDF发动机的有害排放

在一台增压中冷电控单体泵的四缸柴油机上采用柴油/甲醇双燃料（DMDF）燃烧方式进行台架实验,研究了甲醇替代率和不同后处理装置对有害气体、烟度和微粒排放特性的影响。结果表明：在排气管加装柴油机氧化催化转化器（DOC）耦合微粒催化转化器（POC）可以大幅降低双燃料燃烧产生的THC和CO,基本可以实现零排放;与催化前相比,微粒的总数量浓度和总质量浓度均有大幅度降低,平均降幅分别为91.7%和88.1%;烟度排放得到改善,平均降幅为21.9%;同时,该后处理装置对DMDF发动机的NOx排放无明显影响。与之不同,双DOC耦合的后处理装置对THC和CO的催化效率略优于DOC+POC,但在大部分工况下会导致NOx和烟度排放的同时增加。     

Effective utilization of mahua oil blended with optimum amount of Al2O3 and TiO2 nanoparticles for better performance in CI engine

Environmental Science and Pollution Research - The current research work focuses mainly on improving the performance and emission characteristics of nanoparticle-blended mahua oil-fueled diesel...     

Enhancement in combustion,performance, and emission characteristics of a diesel engine fueled with diesel,biodiesel, and its blends by using nanoadditive

This article presents the results of investigations carried out to evaluate the improvement in combustion, performance, and emission characteristics of a diesel engine fueled with neat petro-diesel (PD), soybean biodiesel (SB), and 50% SB blended PD (PD50SB) by using carbon nanotube (CNT) as an additive. The acid–alkaline-based transesterification process with sodium hydroxide (NaOH) as a catalyst was applied to derive the methyl ester of SB. A mass fraction of 100 ppm CNT nanoparticle was blended with base fuels by using an ultrasonicator and the physiochemical properties were measured based on EN standards. The measured physiochemical properties are in good agreement with standard limits. The experimental evaluations were carried out under varying brake mean effective pressure (BMEP) conditions in a single-cylinder, four-stroke, and natural aspirated research diesel engine at a constant speed of 1500 rpm. The results reveal that the SB and its blend promote shorter ignition delay period (IDP) that is resulting in lower in-cylinder pressure (ICP) and net heat release rate (NHR) compared to PD. The SB and its blend increase the brake specific fuel consumption (BSFC), and reduce the brake specific energy consumption (BSEC) and exhaust gas temperature (EGT), due to lower heating value, and efficient combustion, respectively. As far as the emission characteristics are concerned, the SB and its blend promote lower magnitude of hydrocarbon (HC), carbon monoxide (CO), carbon dioxide (CO₂), and smoke emissions compared to PD except for oxides of nitrogen (NO_x) emission. The CNT nanoparticle inclusion with base fuels significantly improves the combustion, performance, and emissions level irrespective of engine load conditions.

     

Effects of air/fuel ratio on gas emissions in a small spark-ignited non-road engine operating with different gasoline/ethanol blends

This study investigates the effects of several blends of gasoline and anhydrous ethanol on exhaust emission concentrations of carbon monoxide (CO), total hydrocarbons (HCs), and nitrogen oxides (NO_x) from a small spark-ignited non-road engine (SSINRE). Tests were carried out for different air/fuel equivalence ratios as measured by lambda (λ). A 196 cm³ single-cylinder four-stroke engine-generator operating at a constant load of 2.0 kW was used; pollutant gas concentrations were measured with an automatic analyzer similar to those typically used in vehicle inspections. The results showed that as the ethanol content of the mixture increased the concentrations of CO, HCs, and NO_x reduced by 15, 53, and 34%, respectively, for values of λ < 1 (rich mixture) and by 52, 31, and 16% for values of λ > 1 (lean mixture). Overall, addition of anhydrous ethanol to the gasoline helped to reduce emissions of the pollutant gases investigated, what contributes to photochemical smog reduction and quality of life in urban areas.     

Effect of compression ratio,nozzle opening pressure,engine load,and butanol addition on nanoparticle emissions from a non-road diesel engine

Currently, diesel engines are more preferred over gasoline engines due to their higher torque output and fuel economy. However, diesel engines confront major challenge of meeting the future stringent emission norms (especially soot particle emissions) while maintaining the same fuel economy. In this study, nanosize range soot particle emission characteristics of a stationary (non-road) diesel engine have been experimentally investigated. Experiments are conducted at a constant speed of 1500 rpm for three compression ratios and nozzle opening pressures at different engine loads. In-cylinder pressure history for 2000 consecutive engine cycles is recorded and averaged data is used for analysis of combustion characteristics. An electrical mobility-based fast particle sizer is used for analyzing particle size and mass distributions of engine exhaust particles at different test conditions. Soot particle distribution from 5 to 1000 nm was recorded. Results show that total particle concentration decreases with an increase in engine operating loads. Moreover, the addition of butanol in the diesel fuel leads to the reduction in soot particle concentration. Regression analysis was also conducted to derive a correlation between combustion parameters and particle number emissions for different compression ratios. Regression analysis shows a strong correlation between cylinder pressure-based combustion parameters and particle number emission.

     

The influence of air–fuel ratio on engine performance and pollutant emission of an SI engine using ethanol–gasoline-blended fuels

Ethanol–gasoline-blended fuel was tested in a conventional engine under various air–fuel equivalence ratios (λ) for its performance and emissions. The amount of fuel injection was adjusted manually by an open-loop control system using a CONSULT controller. It was found that without changing throttle opening and injection strategy, λ could be extended to a leaner condition as ethanol content increased. The results of engine performance tests showed that torque output would increase slightly at small throttle valve opening when ethanol–gasoline-blended fuel was used. It was also shown that CO and HC emissions were reduced with the increase of ethanol content in the blended fuel, which resulted from oxygen enrichment. At an air–fuel equivalence ratio slightly larger than one, the smallest amounts of CO and HC and the largest amounts of CO₂ resulted. It was noted that under the lean combustion condition, CO₂ emission was controlled by air–fuel equivalence ratio; while under the rich combustion condition, CO₂ emission is offset by CO emission. It was also found that CO₂ emission per unit horse power output for blended fuel was similar or less than that for gasoline fuel. From the experimental data, the optimal ethanol content in the gasoline and air–fuel equivalence ratio in terms of engine performance and air pollution was found.