Decrease In NOx Emissions Research Articles

Study on the synergistic effect of NOx and CO2 emission reduction in the industrial sector of Guangzhou

IntroductionAs a major source of pollutant and CO2 emissions, the industrial sector faces the dual challenge of pollution control and carbon reduction. Accurately identifying the synergy between pollutant and carbon emissions in different regions’ industrial sectors is crucial for developing regional policies for coordinated pollution reduction and carbon abatement.MethodsThis study takes Guangzhou as a case study to quantitatively assess the synergistic effect of NOx and CO2 emissions reduction in its industrial sector. First, the LMDI decomposition method was applied to analyze the factors influencing the change in NOx emissions in Guangzhou’s industrial sector. Next, the CFGLS model was used to quantify the synergistic effect between NOx and CO2 emissions. Finally, a robustness check was conducted on the results.Results and discussionThe findings indicate that the synergistic effect in carbon reduction is the most significant driver of NOx reduction in Guangzhou’s industrial sector, with a 10,000-ton reduction in CO2 emissions leading to a 0.4-ton decrease in NOx emissions. The interaction effect analysis shows that increasing the use of natural gas and reducing energy intensity do not amplify this synergy. The results could provide valuable insights for coordinated pollution reduction and carbon abatement policies designing in Guangzhou’s industrial sector.

Influence of Phosphorus Poisoning of Cu/SSZ‐13 Zeolite Catalysts on the SCR Performance

AbstractHerein, the influence of phosphorus poisoning on the catalytic performance of Cu/SSZ‐13 zeolite catalysts for NOx emission decrease was studied. We conducted a detailed analysis of catalyst activity and N₂ selectivity in both fresh and P‐poisoned states, employing a range of advanced physicochemical characterization methods and in situ analyses. Our findings reveal a dual effect of phosphorus addition: Although it decreases the free Cu2+ species and specific surface area, leading to diminished SCR activity at low temperatures, it simultaneously reduces CuOx content, inhibiting nonselective NH3 oxidation at high temperatures and ultimately enhancing SCR activity under those conditions. These insights highlight the complex role of phosphorus in moderating catalyst behavior.

Exploring sustainable fuel alternatives: The role of NH3–H2–H2O2 blends in enhancing HCCI engine performance

This study presents a comprehensive computational analysis of Homogeneous Charge Compression Ignition (HCCI) engines fueled by a carbon-free blend of ammonia (NH3), hydrogen (H2), and hydrogen peroxide (H2O2). The research aims to explore the potential of this blend in enhancing combustion performance and reducing emissions, addressing the critical challenge of environmental sustainability in internal combustion engines. Through the use of detailed kinetic modeling and three-dimensional computational fluid dynamics (CFD), the impacts of various blend compositions on key engine performance was assessed. The kinetic model is validated with the published literature data. The findings indicate that the addition of H2O2 significantly improves autoignition and the combustion duration of an NH3–H2 blend in an HCCI engine is 17° at 515 K. However, with the addition of 40% H2O2, the combustion duration reduces to approximately 16°, even at lower temperatures (395 K). The introduction of 40% H2O2 in the NH3–H2 HCCI engine results in a 12.8% increase in output power and a 22.2% decrease in NOx emissions due to the reduced operating temperature under Maximum Brake Torque (MBT) conditions. With a fuel blend of NH3-0.7, H2-0.2, and H2O2-0.1 at an inlet temperature of 450 K, the combustion duration (CD) is 22°. Increasing hydrogen to 50% and reducing the inlet temperature to about 390 K decreases the CD to 5°. This study demonstrates that the NH3–H2–H2O2 blend holds significant promise as a viable alternative to conventional fuels, potentially contributing to the advancement of zero-carbon emission combustion technologies in future transportation systems.

Hydrogen-enriched lean-burn strategy for gasoline direct injection engine utilizing non-thermal plasma fuel reformer

The objective of the task is to sustain and enhance combustion stability at the extension of lean limit of customized Gasoline Direct Injection (GDI) Engine with the supplementation of Hydrogen Rich Gas (HRG) and hydrogen. HRG was supplemented from the on board non thermal Plasma Fuel Reformer (PFR) and hydrogen from the bottled storage through integrated gas control device to the GDI engine. The gas constituents of PFR was theoretically arrived from thermodynamic combustion equations to determine energy based fuel proportion in the ternary fuel injection system. Binary fuel mixture of HRG and hydrogen 10%, 18%, 30% of energy based proportion with gasoline were experimented on test engine. The impact of discrete and binary fuel mixture with gasoline at Stoichiometric Fuel Air ratio was observed and extended baseline equivalence ratio until misfire of the ternary fuel air mixture was occurred. Apart from significant improvement of performance the addition gaseous mixture increases oxides of nitrogen marginally. From the perspective it was noticed that combustion products exhibit better heat transfer out of cylinder at the Maximum Brake Torque Timing (MBT). This was attributed to higher combustion temperatures and improved quenching distances which in turn increased thermal efficiency against the specified equivalence ratio. However retarding MBT suppresses oxides of nitrogen and continued to increase thermal efficiency. It was concluded that lightning fast burn speed, fine fuel atomization of 10% mass based hydrogen and HRG 18%combination fraction increase engine thermal efficiency while decreasing NOx emission and alleviate HC trade-off characteristics.

Investigation of high percentage of dimethyl ether on biodiesel usage in a diesel engine

Demand for cleaner energy sources both as additive and alternative fuels that can substitute or contribute to the usage of conventional fuels is growing. Researchers have mainly focused on improving or finding a renewable fuel from vegetable oil or addition of chemicals and alcohols for IC engine. This study analyzed the effects of a high percentage of dimethyl ether (DME) combined with biodiesel in a diesel engine. Transesterification method was selected for conversion of pure safflower oil to biodiesel. DME was blended with biodiesel at concentrations of 50% and 25% on a volume basis, respectively. Engine performance and emissions tests demonstrated that the thermal efficiency values were increased at high load operation when the engine was fueled with high percentage of DME. Furthermore, compared to conventional diesel, there has been a notable decrease in NOx emissions. Nevertheless, the introduction of DME blend had negligible effects on CO2 emissions. However, when using a high ratio of DME blend, HC emissions were found to increase, whereas a low ratio of DME blend resulted in decreased HC emissions. Apart from these, some irregularities were observed both on heat release rate and cylinder pressure especially for 50% of DME usage. Finally, the values for both brake-specific fuel consumption and mass fuel of DME-blended fuels were deteriorated.

Vehicle emission models alone are not sufficient to understand full impact of change in traffic signal timings

Few studies have considered the real-world impact of changes in traffic signal timings on air pollution and pedestrian exposure with most only drawing their conclusion from vehicle emission models alone. Here, we consider two distinct cycle timings at a junction in London, UK, model the impact using a traffic microsimulation and a NOx emissions model, and compare these results with NOx and other air pollution measurements collected during a two-week field study at the junction.Our models predict that extending the cycle time leads to a 23% decrease in NOx emissions within a 15 m radius of the junction itself. When the wind direction was such that our sensors were downwind of the junction a 21% decrease in traffic and background-adjusted NOx concentrations were seen, suggesting that the intervention was successful. However, when the sensors were upwind of the junction, we observed an increase of 23% in adjusted NOx concentrations. Similar patterns were found for the other pollutants NO2, lung deposited surface area, black carbon and CO2 we measured. This indicates that meteorology was by far the greatest determinant of roadside concentrations during our two-week study period.Looking at pedestrian exposure for pedestrians waiting to cross the road, we found that their NOx exposure increased by 46% as waiting times to cross the road increased and that potential small reductions in air pollution were offset by increases in waiting times on the main road.The study demonstrates the need to go beyond assessing the impact of hyper-local traffic interventions on vehicle emissions. Real-world trials over extended periods are required to evaluate the impact of meteorology and changes to air pollution concentrations and pedestrian exposures.

Enhancing diesel engine performance and emissions control with reduced Graphene oxide and Non-Edible biodiesel blends

The growing concern about environmental degradation and the depletion of fossil fuel supplies has prompted experts to investigate alternate and sustainable transportation energy sources. In these circumstances, biodiesel made from renewable feedstock has emerged as a viable environmentally friendly alternative to conventional diesel. This study thoroughly examines the performance and emission characteristics of a 4-stroke diesel engine running on biodiesel blends, including reduced graphene oxide (rGO) nanomaterial. The non-edible biodiesel from the Jatropha curcas plant is utilized, and it is blended in various ratios with conventional diesel, ethanol, and nanomaterial rGO to improve performance and emissions parameters. Torque increased by up to 17 % in rGO DJE02GO25 at 3500 rpm, while Brake Power decreased by 6.3 % in rGO DJE01GO25 at 2600 rpm. Brake Thermal Efficiency decreased by 12.5 % in rGO Blend 1 at 2600 rpm, and Brake-specific fuel consumption decreased by 16.5 % in rGO DJE02GO25 at 3500 rpm. CO2 emissions decreased up to 19.71 % in rGO Blend 10 at 2600 rpm. HC emissions decreased to 94 % in rGO blend 8 at 3500 rpm. Finally, NOx emissions decreased up to 84.78 % in rGO Blend 1 at 2900 rpm. The current study reveals that after adding rGO nanomaterial in biodiesel, there is a significant decrease in NOx and HC emissions.

The effects of water injection inside an internal combustion engine regarding NOx emissions

Abstract In this paper we present the influence of water injection on NOx emissions and the performance of a gasoline engine subjected under light to medium loads. The test bench used for measurements has a 4-cylinder, 1.6-liter engine and operates with a wasted spark configuration. Water is injected upstream of the throttle valve through a single injector mounted in the intake runner. The injection timing and amount of water injected inside the engine have been controlled by NI CompactRIO hardware device by the aid of an in-house algorithm implemented in LabView. Water is injected twice at each rotation of the crankshaft in order to have water in all cylinders. The injection of water is done at a fix angle, one time at 0°CA and the other at 360°CA, only the amount is varied from 10% to 45% of the total fuel fraction injected. The results showed that at an amount of water of about 25% of the total fraction of fuel injected, it produced a considerable decrease in NOx emissions, while keeping engine performance unchanged.

Using observed urban NOx sinks to constrain VOC reactivity and the ozone and radical budget in the Seoul Metropolitan Area

Abstract. Ozone (O3) is an important secondary pollutant that impacts air quality and human health. Eastern Asia has high regional O3 background due to the numerous sources and increasing and rapid industrial growth, which also impacts the Seoul Metropolitan Area (SMA). However, the SMA has also been experiencing increasing O3 driven by decreasing NOx emissions, highlighting the role of the local in situ O3 production on the SMA. Here, comprehensive gas-phase measurements collected on the NASA DC-8 during the National Institute of Environmental Research (NIER)/NASA Korea–United States Air Quality (KORUS-AQ) study are used to constrain the instantaneous O3 production rate over the SMA. The observed NOx oxidized products support the importance of non-measured peroxy nitrates (PNs) in the O3 chemistry in the SMA, as they accounted for ∼49 % of the total PNs. Using the total measured PNs (ΣPNs) and alkyl and multifunctional nitrates (ΣANs), unmeasured volatile organic compound (VOC) reactivity (R(VOC)) is constrained and found to range from 1.4–2.1 s−1. Combining the observationally constrained R(VOC) with the other measurements on the DC-8, the instantaneous net O3 production rate, which is as high as ∼10 ppbv h−1, along with the important sinks of O3 and radical chemistry, is constrained. This analysis shows that ΣPNs play an important role in both the sinks of O3 and radical chemistry. Since ΣPNs are assumed to be in a steady state, the results here highlight the role that ΣPNs play in urban environments in altering the net O3 production, but ΣPNs can potentially lead to increased net O3 production downwind due to their short lifetime (∼1 h). The results provide guidance for future measurements to identify the missing R(VOCs) and ΣPN production.

Numerical investigation and optimization of the ammonia/diesel dual fuel engine combustion under high ammonia substitution ratio

This study investigated the effects of initial temperature, equivalence ratio, and diesel injection timing on engine combustion and emission characteristics at high ammonia substitution ratios. Increased compression temperature and pressure significantly reduce ignition delay, enhance combustion speed and efficiency, and decrease N2O and unburned NH3 emissions. A strong correlation exists between the amount of N2O produced and the mass of unburned NH3 when ammonia combustion efficiency is high. The N2O distribution is concentrated near the cylinder walls and the piston top surface, in areas with high concentrations of unburned NH3. As the equivalence ratio increases from 0.6 to 0.75, flame propagation speed and indicated thermal efficiency (ITE) increase, while NOx, N2O, and unburned NH3 emissions decrease. The combustion performance and emissions were optimized by advancing the diesel injection timing and increasing the equivalence ratio to accelerate the combustion speed. This adjustment increases ITE to 47.6 % at an 80 % ammonia energy ratio. Post-optimization results show a reduction in unburned NH3 emissions from 51.7 g/kW·h to 5.9 g/kW·h and a decrease in N2O emissions from 0.930 g/kW·h to 0.370 g/kW·h, culminating in a 60.4 % reduction in greenhouse gas (GHG) emissions.

Spatiotemporal Distributions and Variations in Summertime Ozone Photochemical Production Regimes over Shanxi

Satellite-based formaldehyde（HCHO）columns and tropospheric nitrogen dioxide columns were observed using the Ozone Monitoring Instrument（OMI），and groundbased observations of ozone（O3）for May-August from 2013 to 2022 were connected to calculate the threshold values of the HCHO to NO2 ratio（FNR）in Shanxi Province. Then，the spatiotemporal distributions and variations in summertime ozone photochemical production regimes were analyzed. The results showed that：① The volatile organic compound（VOC） -sensitive regime area（FNR < 2.3）was obviously reduced，while the VOCs-NOx transitional regime（FNR between 2.3-4.1）area increased in the early years and then decreased， and NO x -sensitive regime area expanded significantly in summer from 2013 to 2022 over Shanxi Province. ② The increased summertime FNR during 2013 to 2019 was associated with the co-effect of increased HCHO columns and decreased tropospheric NO2 columns. The Shanxi Province was generally under an NOx regime since 2016，which reflected the remarkable effect of NO x emission reductions；however，there was a shift from a VOC-sensitive regime to a VOCs-NOx transitional regime，in which O3 pollution aggravation was widespread under the background of decreased NOx emissions. The decrease in O3 concentration during 2020 to 2022 followed the synergistical declines in HCHO columns and tropospheric NO2 columns. ③ The O3 weekend effects were reversed in Linfen and Yuncheng but were persistent in the other nine cities. Satellite-based weekend HCHO and NO2 levels were higher than those on weekdays in some cities of Shanxi Province，indicating that the O3 weekend effect was not only dependent on the changes of precursors emissions but was also closely related to O3 photochemical production sensitivity. The results indicated the necessity of simultaneous controls in NOx emissions and VOCs emissions for ozone abatement plans over Shanxi Province. In addition，Taiyuan，Yangquan，Yuncheng，and Jincheng should continue to promote reduction in NOx emissions.

Ammonia energy fraction effect on the combustion and reduced NOX emission of ammonia/diesel dual fuel

With stringent regulations of internal combustion engine on reducing CO2 emission, ammonia has been used as an alternative fuel. Investigating how engine-related performance is affected by partial ammonia replacement of diesel fuel is essential for understanding the combustion. Therefore, in this study, a three-dimensional numerical simulation model is developed for the burning of two fuels of diesel and ammonia based on relevant parameters (i.e., compression ratio, load, ammonia energy fraction, etc.) in a lab-made diesel engine. The consequences of load and compression proportion on combustion and pollutant emissions are investigated for ammonia energy fractions between 50% and 90%. When the ammonia portion rises, the increased ammonia equivalent ratio causes ammonia to move away from the dilute combustion boundary and accelerates the combustion rate of ammonia. An increase in compression ratio significantly increases the specified thermal performance and combustion efficacy. When the compression ratio is 16, as the ammonia energy fractions increases, due to the increase in the proportion of ammonia, that is, the proportion of nitrogen atoms increases, more NOx is generated during the combustion process. When the ammonia substitution rate is 90%, as the compression ratio increases, the cylinder pressure and temperature increase. The combustion efficiency of ammonia increases, generating more NOx and NOx emissions can reach 0.66 mg/m3. At a compression ratio of 18, the NOx emissions can reach 1.59 mg/m3. However, under medium and low load conditions, as the ammonia fraction increases, the total energy of fuel decreases, and the combustion efficiency of ammonia decreases, resulting in a decrease in the heat released during combustion and a decrease in NOx emissions. When the ammonia substitution rate is 90% and the load is 25%, NOx emissions reach 0.1 mg/m3. This research provides theoretical suggestions for the profitable and use ammonia fuel in internal combustion engines in a clean manner.

Optimization of engine performance, emission and combustion parameters by using mixed nonedible oil biodiesel with nano-additives using hybrid techniques

The current study is focused on three nonedible oils resource such as Ceiba pentandra, Mahua longifolia, and Azadirachta indica mixed together in a specific proportion for biodiesel production. The produced biodiesel serves as an alternative fuel source for operating a variable compression ratio diesel engine, addressing escalating environmental pollution and stringent emission standards. A nano-additive comprising CaO–TiO2 is incorporated into biodiesel blends to enhance engine performance and mitigate emissions. The matrix undergoes experimentation and validation using Box-Behnken Design, Deep Belief Network, and a hybrid DBN-based Arithmetic Optimization Algorithm to optimize engine parameters for achieving higher brake thermal efficiency, lower emission rates, and reduced brake-specific fuel consumption. All the experiments are conducted by varying the engine load, speed, quantity of nano-additives and biodiesel blend. The final empirical model is more significant for DBN with a regression coefficient greater than 0.99. The converged optimized input parametric ranges are load 60 %, biodiesel 25 %, nano-additive 20 wt% and engine speed 1400 rpm. When comparing diesel fuel with CaO–TiO2 biodiesel, the proposed method resulted in significant improvements, including a 41 % reduction in brake-specific fuel consumption, a 32 % decrease in CO emissions, a 25 % decrease in NOX emissions, and a 16.9 % increase in brake thermal efficiency.

A numerical investigation on the effect of altering compression ratio, injection timing, and injection duration on the performance of a diesel engine fuelled with diesel-biodiesel-butanol blend

Abstract Using renewable fuels for diesel engines can reduce both air pollution and dependence on fossil fuels. A computer simulation was constructed to predict the performance, combustion characteristics, and NOx emission of a diesel engine fuelled with diesel-biodiesel-butanol blends. The simulation was validated by comparing the modeling results against experimental data and a good agreement between the results was found. The fuels used for the validation were diesel (B0), biodiesel (B100), diesel-biodiesel blend (B50), and two diesel-biodiesel-butanol blends with 45% diesel-45% biodiesel-10% butanol (Bu10), and 40% diesel-40% biodiesel-20% butanol (Bu20) by volume. Experimental results showed that the addition of butanol reduced NOx emissions but deteriorated the engine performance. The aim of the current work was the numerical optimization of the different parameters to enhance the engine performance while using butanol to decrease NOx emissions. The engine compression ratio (CR) varied from 14 to 24, in increments of 2. Fuel injection timing (IT) was retarded from 30° before top dead center (bTDC) to 5° bTDC in increments of 5o. Also, the fuel injection duration (IDur) was extended from 20° to 50° in increments of 10°. Results showed that the increase in CR improved engine performance for the two investigated fuels, Bu10 and Bu20. The maximum engine brake power (BP), thermal efficiency (BTE), and minimum brake-specific fuel consumption (BSFC) of 1.46 kW, 32.3%, and 0.273 kg/kWh respectively, were obtained when the Bu10 fuel was injected at the optimum conditions of 24 CR, 15°bTDC IT, and 40° injection duration (IDur). Under these optimum conditions, the BP, BTE, and BSFC improved by 3% to 3.5% for Bu10 and Bu20 fuel blends compared to the base engine conditions of CR of 22, 30° IDur, and 10° bTDC IT. The heat release rate during the premixed phase increased when the IT was advanced, while the mixing-controlled combustion phase was enhanced when the IT was retarded. NOx emissions increased with increasing the CR, while both the increase in IDur at constant IT and the retard of IT decreased engine NOx emissions. At the optimum conditions, the NOx emissions for Bu10 and Bu20 were further decreased by 2.2% and 0.9% respectively compared to the experimental results at base engine conditions. Retarding the injection timing from 15° bTDC to 5° bTDC at a CR of 24 and IDur of 40° caused the NOx emissions for Bu10 and Bu20 to decrease by 16%. When the injection duration was increased from 20° to 50° at a CR of 24 and an IT of 15°bTDC, the NOx emissions for Bu10 and Bu20 decreased by 12.3% and 11.8% respectively. The addition of butanol to the diesel-biodiesel blend at optimum conditions showed results comparable to pure diesel, with a decrease in NOx emissions.

Combustion characteristics of premixed ammonia-hydrogen/air swirl flames at elevated pressure

Ammonia (NH3)-hydrogen (H2) blends which are obtainable by NH3 cracking can be an eminent carbon-free fuel. To provide a valuable database for the practical application of cracking-based NH3-H2 fuel, the effects of pressure on the combustion characteristics of premixed NH3-H2(-nitrogen (N2))/air swirl flames are investigated in terms of H2 mole fraction in the NH3-H2 blend and fuel-equivalence ratio. Extinction mechanisms at fuel-lean and rich flames are the same for both normal and elevated pressures, though only the blowoff is observed for elevated pressure. With increasing pressure, fuel-rich limits are generally extended but fuel-lean limits are reduced, NOx emissions decrease and the condition of the maximum NOx emissions moves towards fuel-richer condition. Flame visualization exhibits the shifted main reaction zone upstream, the increased flame wrinkling and the reduced OH and NO intensities with increasing pressure. Dilution effects of N2 at elevated pressure become remarkable compared with those at normal pressure.

Global health benefits of shipping emission reduction in early 2020

The impact of COVID-19 lockdown on the absolute concentration of air pollutant has been widely investigated, whereas the impact of lockdown on global shipping-related air pollutants still remained poorly understood because the contribution of individual source cannot be observed directly. In our study, we employed an efficient chemical transport model (GEOS-Chem) to quantify the shipping-related PM2.5, NO2, and O3 levels in early 2019 and 2020, and assessed the impact of COVID-19 lockdown on global shipping-related air pollutants and health effects. The result suggested that shipping-related global PM2.5, NO2, and O3 levels reduced by 14%, 85%, and 1%, respectively. Furthermore, the decreasing ratios of air pollutants in difference regions often suffered from large spatial discrepancy. PM2.5 and NO2 levels in China, India, Europe, and the United States decreased by 6.5% (NO2: 9%), 7.4% (8%), 11% (8.6%), and 15% (10%), which could be caused by dense shipping activities during the non-lockdown period. For O3 concentrations, the shipping-related concentrations in China, India, Europe, and the United States showed 0.7%, −12.9%, 16.6%, and −4.8% during lockdown period, respectively. The relatively slight O3 reduction might be linked with more significant decrease of NOx emission than VOCs. The changes of air pollutant concentrations inevitably led to the variations of health benefits. Globally, the all-cause mortalities caused by shipping-related PM2.5 exposures reached 40,464 (95% CI: 26,546, 54,382) and 39,035 (95% CI: 25,135, 52,935) cases in early 2019 and 2020, respectively. The combined health benefits of PM2.5, NO2, and O3 linked with shipping emission reduction in China, India, Europe, and the United States reached 476 (95% CI: 131, 822), 3341 (95% CI: 3,177, 3505), 2194 (95% CI: −970, 5358), and 311 (95% CI: 242, 379), respectively. Our study confirms the potentially considerable effects of shipping emission on multiple air pollutants and health impacts, which could provide valuable information for air quality management.

Effect of antioxidants on CI engine characteristics of safflower biodiesel with varying fuel injection pressures

A product of microorganisms, crop plants, and animal-based oil, biodiesel holds excellent promise as a sustainable energy resource and a solution to the world's rising energy issues. Biofuel resembles the qualities of fossil diesel, while it is also proven to be a greener fuel and viable alternative. To enhance the properties of biodiesel, the additives, mainly antioxidants, were added to the 20 % blend of safflower biodiesel (B20) at various injection pressures (190, 200, and 210 bar). At a concentration of 1000 ppm, the antioxidants, namely BHA (butylated hydroxy anisole) and BHT (butylated hydroxytoluene), were added to the B20 blend of higher IP. Investigation on the effects of antioxidants with biodiesel on the performance and emission characteristics were tested in CI diesel engines at different injection pressures (IP). The findings from this study indicate that antioxidants added to biodiesel significantly improved the engine's performance. Higher IP resulted in higher BTE (1.6 %) with lesser emissions of CO (33.33 %), HC (10 %) and smoke (19.5 %) than diesel. But it emits higher NOx emissions (2.5 %). The addition of the antioxidant BHA showed a decrease in NOx emissions by 5 % to higher IP. Thus, the safflower biodiesel B20 added with antioxidant BHA will likely be a tremendous alternate fuel for the CI engine.

Ozone Pollution in the North China Plain during the 2016 Air Chemistry Research in Asia (ARIAs) Campaign: Observations and a Modeling Study

To study air pollution in the North China Plain (NCP), the Air Chemistry Research in Asia (ARIAs) campaign conducted airborne measurements of air pollutants in spring 2016. High pollutant concentrations, with O3 &gt; 100 ppbv, CO &gt; 500 ppbv, and NO2 &gt; 10 ppbv, were observed. CMAQ simulations with the 2010 EDGAR emissions capture the spatial and temporal variations in ozone and its major precursors such as NO2 and VOCs, with significant underestimation. Differences between CMAQ simulations and satellite observations reflect changes in anthropogenic emissions, decreased NOx emissions in megacities such as Beijing, but slight increases in other cities and rural areas. CMAQ also underestimates HCHO and CO, suggesting adjustments of the 2010 EDGAR emissions are necessary. HCHO/NO2 column ratios derived from OMI measurements and CMAQ simulations show that VOC-sensitive chemistry dominates the ozone photochemical production in eastern China, suggesting the importance of tightening regulations on anthropogenic VOC emissions. After adjusting emissions based on satellite observations, better model performance was achieved. Because of the VOC-sensitive environment in ozone chemistry over the NCP, the underestimation of anthropogenic emissions could be important for CMAQ simulations, while future study and regulations should focus on VOC emissions with continuous controls on NOx emissions in China.

The effect of fusel oil and waste biodiesel fuel blends on a CI engine performance, emissions, and combustion characteristics

In this study, experimental engine tests were conducted to investigate the combustion, performance, and emission characteristics of a diesel engine using a fuel blend composed of diesel, biodiesel, and fusel oil. In the study, which was carried out by using fuels obtained from different wastes together in a diesel engine. Seven different fuels were prepared for experiments by adding waste cooking oil (30% and 50%) and fusel oil (5% and 10%) by volume to commercial diesel fuel. The tests were carried out on the Lombardini LDW 1003 engine, a three-cylinder diesel engine, at four different engine loads (10, 20, 30, and 40 Nm), and a constant speed (2000 rpm). The experimental results revealed that the use of WCO generally led to increased NOx emissions which generally decreased with the fusel oil addition to the fuel mixture. Considering diesel fuel as a reference at maximum load conditions, there was a 12.63% increase in NOx emissions with 50% WCO. A 2.45% decrease in NOx emissions was achieved by adding 10% fusel oil. Furthermore, HC emissions decreased with the addition of both fusel oil and WCO at all load levels. When diesel fuel is taken as a reference at maximum load conditions, a 90% reduction in HC emissions was achieved by adding 50% WCO, and a 50% reduction in HC emissions was achieved by adding 10% fusel oil. Additionally, when diesel fuel is taken as a reference at maximum load condition, it was observed that a 0.05% increase in the maximum cylinder pressure value with the addition of 50% WCO and a 2.09% increase in the maximum cylinder pressure value with the addition of 10% fusel oil.

Experimental investigation of engine performance and emissions, and characterization, of waste transformer oils and diesel blends with biodiesel produced from olive oil wastes in a CI engine

In this study, five different fuel blends were prepared by mixing biodiesel obtained from olive oil wastes using transesterification method, waste transformer oil, and Euro diesel in different ratios. The important physicochemical properties of the prepared fuel blends and produced biodiesel were determined by gas chromatography, Fourier transform infrared spectroscopy, and thermogravimetric analysis/differential scanning calorimetry analyses, and their characterizations were carried out. Then, the effects of the prepared fuel blends on engine performance and emission characteristics were investigated in a compression ignition engine. The experiments were performed with five different fuel blends (TD30, TD30B10, TD30B20, TD30B30, and D100) at 1000, 1500, 2000, and 2500 rpm. At all speeds, each fuel blend produced an average torque value that was highest for D100 fuel and lowest for TD30 fuel The average BP value produced by each fuel at all engine speeds was highest in D100 fuel and lowest in TD30 fuel. The results of the experiments showed that there was a 23.98% decrease in the average NOx emissions of TD30 fuel blend compared to the average NOx emissions of D100 fuel at all engine speeds. It was observed that all important fuel properties such as density, kinematic viscosity, and pour and cloud points of all fuel blends met the fuel standards.