郑州市大气环境状况及可持续发展对策

Increased energy efficiency and the rebound effect: Effects on consumption and emissions

The article examines the urgent problem of atmospheric air pollution in Ivano-Frankivsk region caused by anthropogenic factors. The main attention is paid to the analysis of the structure and dynamics of pollutant emissions from stationary sources, in particular carbon dioxide, sulfur compounds, solid suspended particles, nitrogen and other substances. The analysis of trends in total pollution for the period from 1990 to 2023 has been presented, taking into account economic, social and environmental factors. It has been found that in 2023, total emissions from stationary sources decreased by 3.02% compared to 2022 and amounted to 147.7 thousand tons. The main pollutant remains carbon dioxide (9.9 million tons), which is the main greenhouse gas and contributes to climate change. The structure of emissions of other pollutants has been investigated: a significant share is made up of sulfur dioxides (65%), solid suspended particles (17%), nitrogen compounds (9%), methane (4%), and non-methane volatile organic compounds (3%). The dynamics of changes in emission levels in the context of economic, environmental and technological factors, including the impact of the COVID-19 pandemic, has been presented. Particular attention is given to analyzing emissions of nitrogen dioxide, sulfur dioxide, particulate matter, and nitrogen oxides, as well as their impact on ecosystems and public health. The results of the study show a gradual decrease in atmospheric air pollution in the region, which is a consequence of a decrease in carbon dioxide and sulfur dioxide emissions, but emissions of volumes of emissions of solid suspended particles and nitrogen oxides have increased in recent years. Therefore, the development of alternative energy, the introduction of the latest emission treatment technologies, the popularization of environmentally friendly transport, and the strengthening of environmental monitoring remain actual for the region.

This paper examines how economic growth and renewable energy consumption are associated with air pollution using a dynamic panel approach. Focusing on several major air pollutants, namely, particulate matter, sulfur dioxide, nitrogen oxide, and carbon monoxide, this paper tests the environmental Kuznets hypothesis and determines whether the use of renewable energy sources contributes to a reduction in air pollution. Data from a balanced panel of 145 countries for the period between 2000 and 2014 was used for the estimation of the dynamic panel model. The results of the dynamic panel model showed inverted U-shaped curves for the relationship between economic development and particulate matter and sulfur dioxide emissions. The results also revealed that increasing renewable energy consumption contributes to an improvement in air quality. Moreover, it was found that urbanization tends to decrease sulfur dioxide and nitrogen oxide emissions, while trade openness reduces particulate matter and carbon monoxide emissions but increases sulfur dioxide emissions.

Remote sensing of PM, NO, CO and HC emission factors for on-road gasoline and diesel engine vehicles in Las Vegas, NV

Remote sensing of PM, NO, CO and HC emission factors for on-road gasoline and diesel engine vehicles in Las Vegas, NV

Emission Effects of Shell LOW NOX Fuel on a 1990 Model Year Heavy Heavy-Duty Diesel Engine

Electric power generating plants that use coal were among the key targets of Title IV of the 1990 Clean Air Act. Under the first phase of the act, 110 coal-fired electric power plants were required to reduce their sulfur dioxide emissions by 1995 and nitrogen oxide emissions by 1996. Phase 2 of the act requires even greater reduction of sulfur dioxide emissions by 2000 and nitrogen oxide emissions by 2008. This study examines whether the 107 targeted plants (three plants went off-line) have achieved the desired sulfur dioxide and nitrogen oxide emission levels. The analysis of sulfur dioxide is based on data from 1990, 1995, and 1999. The findings show that although sulfur oxide increased by 3% from 1995 to 1999, it decreased by 45% over the 1990-1999 period at the firm level for the targeted firms. The findings also indicate that the overall reduction in sulfur dioxide was achieved by utilizing low sulfur coal and by purchasing emission allowances. So far as nitrogen oxides are concerned, there has been a reduction of 14% over the 1990-1999 period, of which 7% was achieved during the 1995-1999 period. An evaluation of emissions at the plant level indicates that several plants do not meet the emissions level for sulfur dioxide or nitrogen oxides. These results provide a mixed scorecard for reduction in emissions both for sulfur dioxide and nitrogen oxides. Even though there is reduction in the emissions on an overall basis at the firm level, several plants that have not been able to reduce emissions deserve special attention to meet the goals of the act in reducing emissions.

Two methods for reducing nitrogen oxides (NOX) emissions from direct injection, compression ignition, heavy-duty engines are exhaust gas recirculation (EGR) and the high-pressure direct injection of natural gas. Tests combining these two techniques were carried out on a single-cylinder research engine (SCRE) based on a modified heavy-duty automotive engine. No attempt was made to optimize the engine's combustion chamber or the injector geometry for EGR operation. The SCRE's independent charge-air system allowed for more controlled testing over a wider range of test variables than can be carried out by a standard engine. These tests investigated the effects of cooled EGR on particulate matter (PM) and NOX emissions while varying the injection timing, engine speed, equivalence ratio and intake manifold pressure. The results suggested that, with EGR, higher equivalence ratios reduced power-specific NOX but increased PM emissions. Increasing the charge mass at a constant EGR fraction resulted in significant reductions in PM, at the cost of slightly increased NOX By advancing the injection timing at high EGR fractions, PM emissions and fuel efficiency were improved, with only a slight increase in NOX emissions compared to the more retarded injection timings. The engine speed influenced the amount of EGR that could be recirculated, with lower speeds resulting in higher achievable EGR fractions. These results suggest that EGR fractions in excess of 20 per cent can achieve NOX reductions beyond 75 per cent, without causing unacceptable increases in PM emissions or significant reductions in fuel efficiency.

Acid deposition is a serious problem throughout much of Asia. Emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) have been increasing steadily, as nations strive to increase their levels of economic development. Coal and fuel oil have been the main choices for powering industrial development; and, until recently, only a few countries had taken steps to avert the atmospheric emissions that accompany fuel combustion. This paper discusses trends in emissions of SO2 and NOx that have occurred in Asian countries in the period 1985–1997, using results from the RAINS-Asia computer model and energy-use trends from the IEA Energy Statistics and Balances database. Emissions of SO2 in Asia grew from 26.6 Tg in 1985 to 33.7 Tg in 1990 and 39.2 Tg in 1997. Though SO2 emissions used to grow as fast as fossil-fuel use, recent limitations on the sulfur content of coal and oil have slowed the growth. The annual-average emissions growth between 1990 and 1997 was only 2.2%, considerably less than the economic growth rate. Emissions of NOx, on the other hand, continue to grow rapidly, from 14.1 Tg in 1985 to 18.7 Tg in 1990 and 28.5 Tg in 1997 (6.2% per year between 1990 and 1997), with no signs of abating. Thus, though SO2 remains the major contributor to acidifying emissions in Asia, the role of NOx will become more and more important in the future.

With the rises in population, number of vehicles, energy consumption, and economic activity in the Seoul metropolitan area, it is difficult for existing environmental policies and measures to mitigate air pollution. To respond to such challenges, the Ministry of the Environment of the Republic of Korea enacted the Special Act on Metropolitan Air Quality Improvement (SAMAQI) in December 2003. The Special Act is effective from January 2005. Because the transport sector is rapidly growing in the Seoul metropolitan area, we discuss the possible impact of this Special Act on emissions of sulfur dioxide (SO2), nitrogen oxide (NOx), carbon monoxide (CO), particulate matter (PM), and carbon dioxide (CO2) from the transport sector in Seoul. For this policy analysis, the AIM/local model (Asia-Pacific Integrated Model for Evaluating Policy Options to Reduce Greenhouse Gas Emission and Global Warming Impacts) is used. SAMAQI is expected to affect the emission profiles of air pollutants in the Seoul metropolitan area with the introduction of diesel passenger cars. This article analyzes the various policy scenarios along with projections of key determinants in the transport sector in this area. With such stringent emission standards and other policies and measures envisioned by the Special Act, the introduction of new vehicles equipped with advanced technologies and energy efficiency improvements will be accelerated, which will contribute to the reduction of air pollutants and CO2 emissions simultaneously.

Emissions were measured from seven heavy-duty (HD) on-road vehicles that were operated along six common route types used for freight transport in California. All vehicles had engines that were certified to the 0.01 g/bhp-h particulate matter (PM) and either a 0.2, 0.3, or 2.3 g/bhp-h nitrogen oxide (NOx) standard. Diesel vehicles had low carbon monoxide (CO) and total hydrocarbon (THC) emissions below brake-specific standards, with route averages ranging from 0.24 to 3.35 g CO/mi and from 0.02 to 0.45 g THC/mi. Diesel vehicles equipped with selective catalytic reduction (SCR) had route average NOx emissions ranging from 0.58 to 3.99 g/mi (0.16 to 0.96 g/bhp-h). NOx emissions were less route-dependent for the one vehicle with a 12-L compressed natural gas (CNG) engine and three-way catalyst (TWC), with route averages ranging from 0.16 to 0.46 g/mi (0.06 to 0.13 g/bhp-h). The ranking of certification NOx emissions for the seven engines reported during engine-dynamometer-based certification was not maintained during real-world testing; for example, highway driving NOx emissions were lower than certification values for some engine families and higher than certification values for others. Route-average gravimetric particulate matter (PM) emissions ranged from 4 to 12 mg/mi, which on a brake-specific basis were at least two times below the 0.01 g/bhp-h standard. Ion speciation of PM emissions indicated that the most prevalent species were sulfate (SO4 2−) for the model year (MY) 2007 diesel vehicle equipped with a diesel particulate filter (DPF) and no SCR, nitrate (NO3 −) for conventional diesel vehicles with a DPF and SCR, and sodium (Na+) was the most abundant species for the CNG vehicle. NOx and PM emissions were compared to, and show generally good agreement with, the latest California mobile source model (EMFAC2014).

A high temporal-spatial emission inventory and updated emission factors for coal-fired power plants in Shanghai, China

Alternative fuel vehicles are gaining importance as a means of reducing petroleum dependence. One attractive option is biodiesel, a renewable diesel fuel produced from plant or animal fats, since it significantly reduces carbon monoxide, unburned hydrocarbon, and particulate matter emissions as well as carbon dioxide when considered on a full life cycle basis. However, biodiesel combustion also typically results in increased fuel consumption and nitrogen oxide (NOx) emissions relative to petroleum diesel. In order to determine the cause of and develop mitigation strategies for increased biodiesel fuel consumption and NOx emissions, an accurate simulation model was developed and validated. Key fuel properties as well as ignition delay characteristics were implemented in a previously validated whole engine model to reflect soy-biodiesel fuel. The model predictions were within 5% of experimental results for most values at the three operating points. Using this biodiesel model, the “biodiesel NOx effect” was linked to the near stoichiometric equivalence ratios for biodiesel.

The new European directive for the promotion of renewable energy mandates an increase in the share of advanced and waste-based biofuels in the transport sector. In this study, an advanced glycerol-derived biofuel was used as a component of a ternary blend, denoted as o·bio®. This blend included 27.4 %v/v of fatty acid glycerol formal ester, 69.6 %v/v of fatty acid methyl ester and 3 %v/v of acetals obtained as a by-product of the fatty acid glycerol formal ester production process (which were proved to improve cold-flow properties). Finally, o·bio® was blended with diesel fuel at a content of 20 %v/v. Two operating conditions based on usual driving modes were selected, where the engine calibration could be re-optimized after the change of fuel, corresponding to vehicle velocities of 50 and 70 km/h. Since the main effect of the blend used is to reduce particulate matter emissions, exhaust gas recirculation was increased and injection was delayed, so that the initial benefits in particulate matter emissions could be re-distributed into benefits in both particulate matter and nitrogen oxides (NOx) emissions. From a combined analysis of the particulate matter–NOx trade-off and trying to limit the negative effect of delaying injection on fuel consumption, the final proposal was to set an additional 6% exhaust gas recirculation at 50 km/h and an additional 3% exhaust gas recirculation at 70 km/h, while delaying injection 2 °CA after top dead center at both vehicle operating conditions with respect to the original calibration. The use of the blend along with the optimization of the engine calibration is expected to reduce particulate matter and NOx emissions by around 50% with a vehicle speed condition of 50 km/h and to reduce particulate matter and NOx emissions by around 30% and 40% at 70 km/h with respect to diesel fuel emissions.

Abstract. Cheap renewable fuels are needed to replace fossil fuels to reduce greenhouse gas emissions that are causing global warming with the attendant negative consequences. The properties of blends of spent groundnut oil methyl ester (SGOME) and fossil diesel and the emissions from these blends as engine fuel were determined. Spent groundnut oil (SGO) was transesterified into SGOME using methanol and potassium hydroxide as catalyst. The SGOME was blended with fossil diesel and the properties determined and compared to fossil diesel (B0). The pure SGOME (B100) was blended with 90%, 80%, 70%, 60%, and 50% diesel to obtain the B10, B20, B30, B40, and B50 blends of biodiesel, respectively. The properties of the SGOME and the blends were determined according to ASTM and AOCS standards for biodiesel. The properties determined were flash point, carbon residue after combustion, pour and cloud points, kinematic and dynamic viscosities. The blends were used as fuel in a single cylinder 4-stroke water-cooled compression ignition engine that was coupled to a dynamometer from which the tail pipe emissions were measured using gas analyzers. The emissions were measured after the engine had reached a steady state at no load (0 kW) and 1 kW at 3 min interval for 15 min for each blend in 3 replicates. The greenhouse gas emissions measured were nitrogen oxide (NOx),hydrogen sulphide (H2S), particulate matter (PM), sulphur dioxide(SO2),and carbon monoxide (CO). The analysis of variance (ANOVA) at p = 0.05 was used to determine if there was significant difference in the amount of gas emitted from the various blend fuels. The F-LSD was used to separate the means where there was significant difference. The higher blends of the SGOME had better flash point, pour point, and dynamic viscosity than the lower blends. However, the lower blends had better cloud point. The carbon residue after combustion of the SGOME blends was better than that of the fossil diesel. The NOx, PM, SO2, and CO emissions were significantly different from the various blends of the SGOME. However, the H2S emission was not significantly different. Loading the engine did not significantly affect the NOx, H2S, SO2, and CO emissions but significantly affected the PM emission. The PM, CO, and SO2 emissions were highest from the fossil diesel and the lower blends (B10, B20, and B30) and lowest from the higher blends (B40, B50, and B100) at both engine loads. The NOx emission was lowest from the fossil diesel and the lower blends. The use of B20 increased the NOx emission by 10% at both engine loads. The H2S emission was the same for the fossil diesel, pure SGOME (B100), and the blends (B10–B50) at both engine loads. The SGOME fuel reduced tail pipe emission of PM, CO, and SO2 by 26%, 45%, and 78%, respectively. The higher blends had a considerably lower amount of toxic emissions at both engine loads. Keywords: Blends, Diesel, Emissions, Engine, Fuel, Properties, Spent groundnut oil methyl ester.