Comparative effects of oxygenates-gasoline blended fuels on the exhaust emissions in gasoline-powered vehicles

Light-duty vehicle organic gas emissions from tailpipe and evaporation: A review of influencing factors

Vehicle organic gas emissions are becoming an increasingly significant pollution source in many cities, leading to serious negative impacts on human health and the environment. However, interest in vehicular emissions is currently mostly focused on the emission characteristics of regulated gas, while little information is available on the systematic overview of organic gas emissions, particularly under different conditions. This review classifies the current status of research and control measures regarding organic gas emissions from light-duty vehicles. The key factors influencing tailpipe and evaporative emissions, including temperature, fuel composition, vehicle mileage, driving conditions, and road conditions, are identified. Building upon this review, we conducted a case study to comprehensively assess the impact of temperature and fuel on organic gas emissions. Looking ahead, future research on organic gas emissions from motor vehicles could delve deeper into the component characteristics, evaporative emissions, and model applications. Better understanding the effects of crucial factors on organic gas emissions from vehicles would aid in effectively managing and regulating tailpipe and evaporative emissions, thereby improving atmospheric air quality.

Qualitative assessment of regular and premium gasoline available in Bangladesh markets

Assessing the quality of fuel is essential to comprehend its impact on the environment and human health. In this study, the evaluation of fuel quality standards at the consumer level was conducted by analyzing the motor fuels in Khulna, Bangladesh. A total of 32 samples of petrol (regular gasoline), and octane (premium gasoline) were collected from the fuel stations in the Khulna City Corporation area and analyzed with an FTIR-Fuel Analyzer. Fuel properties, such as research octane number (RON), motor octane number (MON), ethanol content, olefins content, and oxygen content were analyzed. For petrol, the average RON, MON, olefins, and oxygen content were 95.34, 85.70, 8.23 %v/v, and 0.78 %m/m, respectively, and for octane, they were 96.96, 85.39, 1.25 %v/v, and 0.09 %m/m, respectively. Almost all of these parameters complied with both Bangladesh standard and Euro 5 fuel specifications, and those that did not comply were very close to their standard values. However, benzene concentration, which was not specified in Bangladesh Standard, was the most alarming metric for octane since none of the samples matched the Euro 5 fuel specifications of the maximum concentration of 1 %v/v benzene; on average it was 3.70 %v/v. Although petrol benzene content (average 1.50 %v/v) was not as bad as it was for octane, it was still nowhere near good enough, with only 25% of the samples within the recommended level among the studied sample. This information holds significance in establishing the fuel profile and facilitating the identification of distinct samples linked to adulteration. Therefore, the analysis of motor fuel qualities is essential for maintaining the environment, human health, and the economy of a country.

Effects of meteorological parameters and fuel composition on the air pollution production from motor vehicles

The aim of this study was to investigate the effect of changes in meteorological parameters and fuel composition on the emission rate of air pollutants in the vehicle fleet of the Tehran Metropolis. The results of this study can be used in management decisions to reduce the emission of air pollutants. In this paper, based on the international vehicle emission model and using mathematical equations, the effects of changing meteorological parameters and fuel composition on the emission of pollutants were modeled. The emission rates of CO, VOCs, and NOx pollutants were the most sensitive to the changes in meteorological parameters, respectively. Among all parameters studied in this research, the changes in sulfur level had the greatest effect on the emission of pollutants from the vehicle fleet of Tehran Metropolis. If the fuel was replaced with Euro 5 standard instead of Euro 3, the emission rates of CO, VOCs, NOx, PM, and SOx pollutants from the vehicle fleet of Tehran Metropolis would be reduced by 9%, 6%, 5%, 14%, and 90%, respectively. Managing and reducing the sources of production and emission of air pollution is one of the best ways to reduce the air pollution. In general, since the emission of pollutants from the fleet of Tehran Metropolis in the cold seasons of the year is greater than during hot seasons and the problem of air pollution is exacerbated by air stability, using Euro 5 fuel in cold seasons is one of the efficient ways to reduce the air pollution.

Effects of cordierite particulate filters on diesel engine exhaust emissions in terms of pollution prevention approaches for better environmental management

In this study, a specific diesel fuel is experimentally tested in a 4-cylindered diesel engine with and without a cordierite-based diesel particulate filter (CPF) to show the prevention of emissions by using an after treatment system (ATS). In this context, engine exhaust emissions, total particle concentration (TPC) and soot concentration are investigated. The diesel engine is firstly evaluated with the data directly measured from the engine output (DEO) (without after treatment option), and then the changes in the exhaust emission are examined by using an ATS which is a cordierite-based diesel particulate filter to prevent pollution. In this regard, total particle concentration of DEO option is found to be 6134041.20 1/cm³ and total particle concentration by using CPF is obtained to be 707.84 1/cm³. 99.99% reduction in TPC is achieved thanks to the use of CPF. The soot concentration of DEO option is calculated to be 2.158 mg/m³. However, the soot concentration is found to be 0.014 mg/m³ by using the CPF. The particulate matters are burned at high temperatures after being filtered at the exhaust output thanks to the regeneration process within the CPF after treatment. CO emissions decreased from 0.7489 g/kWh to 0.7273 g/kWh with the CPF utilization, while HC emissions decreased from 0.0965 g/kWh to 0.0900 g/kWh via CPF. However, an increase in CO₂ and NO_x emissions are observed due to oxidation in the CPF.

On-Road Emission Characteristics of Volatile Organic Compounds from Light-Duty Diesel Trucks Meeting Different Emission Standards : Investigation on the characteristics of tailpipe volatile organic compound emissions with a portable emissions measurement system

On-road tailpipe volatile organic compounds (VOCs) were sampled from light-duty diesel trucks (LDDTs) compliant with Euro III to V, and a total of 102 VOC species were quantified. The composition characteristics and carbon number distributions were investigated, and the contribution of individual VOC to ozone formation potentials (OFPs) was weighted. Results showed that alkanes were the major VOC species, accounting for approximately 65.5%. VOC emissions decreased significantly as the standards became stricter, especially for alkanes and aromatics; and the VOC emissions on highway were much lower than those on urban roads. Carbon number distribution of VOCs was mainly concentrated in C3‐C4 and C10‐C12. Aromatics were the major contributors to ozone formation, taking up 49.3‐57.6% of the total OFPs, and naphthalene, 1-butene, dodecane, 1,2,3-trimethylbenzene and 2-propenal were the top five species. The information provided insight into the tailpipe VOC emission characteristics and may help decision makers drafting related emission policies.

Emission characteristics and ozone formation potentials of gaseous pollutants from in-use methanol-, CNG- and gasoline-fueled vehicles

Alternative-fueled vehicles have been introduced to solve the problem of the energy crisis and address air pollution. However, typical pollutants (e.g., methane and methanol) are emitted through combustion of the alternative fuel. In this study, the concentrations of regulated pollutants (CO, NO) and unregulated pollutants (CH₄, methanol, formaldehyde, and 8 NMHC species) in the exhaust from methanol, CNG, and gasoline-fueled vehicles (MV, NGV, and GV) were measured systematically on a chassis dynamometer during an in-use vehicle driving cycle. The emission factors of these gaseous pollutants were calculated, and the ozone formation potential (OFP) of each ozone precursor measured in this work was evaluated with the MIR scale. The results showed that NO and NMHC species exhausted from the MV and NGV decreased significantly than that from the GV. However, the unburned pollutants exhausted from MV and NGV warrant attention. For the OFPs, CO was the largest contributor for all tested vehicles. Formaldehyde was ranked the second for the MV and NGV. Among the tested vehicles, the OFPs of NGV were the lowest. The results are helpful in quantitating analysis of the vehicle emissions and evaluating the impacts of alternative-fueled vehicles on atmospheric environment.