Exhaust Gas Emissions Research Articles

Utilization of Palm Frond Waste as Fuel for Co-Firing Coal and Biomass in a Tangentially Pulverized Coal Boiler Using Computational Fluid Dynamic Analysis

Renewable energy sources are becoming increasingly crucial in the global energy industry and are acknowledged as a significant substitute for fossil fuels. Oil palm fronds are a type of biomass fuel that can be utilized as a substitute for fossil fuels in the combustion process of boilers. Co-firing (HT-FRD) is a beneficial technology for reducing exhaust gas emissions generated by coal-burning power stations. By utilizing computational fluid dynamics (CFD), this study has modeled and evaluated co-firing palm frond residue (HT-FRD) with hydrothermal treatment into a 315 MWe boiler. In the simulation, six different HT-FRD co-firing ratios, 0%, 5%, 15%, 25%, 35%, and 50%, were used to demonstrate the differences in combustion characteristics and emissions in the combustion chamber. The data indicate that HT-FRD co-firing can enhance temperature distribution, velocity, and unburned particles. All in all, co-firing conditions with 5–15% HT-FRD ratios appear to have the most favorable combustion temperature, velocity, and exhaust gas characteristics.

The Correlation of the Smart City Concept with the Costs of Toxic Exhaust Gas Emissions Based on the Analysis of a Selected Population of Motor Vehicles in Urban Traffic

The intensive development of road transport has resulted in a significant increase in air pollution. This phenomenon is particularly noticeable in urban areas. This creates the need for analyses and forecasts of the scale and extent of future emissions of harmful substances into the environment. The aim of this study was to estimate the costs of the emission of toxic components of exhaust gases generated by all users of conventionally propelled vehicles travelling on a section of urban road in the next 25 years. The traffic study was carried out on an urban traffic route, playing a key role for road transport in the dimension of a given urban agglomeration. The traffic forecast for the analysed road section was based on the results of our own measurements carried out in April 2023 and external data from the General Directorate for Roads and Motorways. The results of the observations concerned six categories of vehicles for the morning and afternoon rush hours. Based on the data obtained, the generic structure of the vehicle population on the analysed section and the average daily traffic were determined. Using the methodology contained in the Blue Book of Road Infrastructure, parameters were calculated in the form of annual indicators of traffic growth on the analysed section, travel speed, and annual air pollution costs for selected vehicle categories, remembering at the same time that the Blue Book-based methodology does not distinguish between unit costs in relation to the type of emissions. The results of the study confirmed that there was an increase in the cost of toxic emissions for each vehicle category over the projected 25-year period. The largest increases were seen for trucks with trailers and passenger cars. In total, for all vehicle categories, emission costs nearly doubled from 2024 to 2046, from EUR 3,745,229 to EUR 7,443,384, due to the doubling of the number of vehicles resulting from the traffic forecast. The analyses presented here provide an answer to the question of what pollution costs may be faced by cities in which road transport will continue to be based on conventional types of propulsion. In addition, the research presented can be used to develop urban mobility transformation plans for the coming years, within the scope of the widely promoted smart city concept and the idea of electromobility, by pointing out to local authorities the direct economic benefits of these changes.

The Catalytic Mechanisms and Design Strategies of Noble Metal Catalysts for Selective Reduction of NOx with CO

AbstractThe selective catalytic reduction of NOx by CO (CO‐SCR) is a viable method for simultaneously mitigating NOx and CO emissions in motor vehicle exhaust and industrial flue gases. Extensive research has been conducted on noble metal catalysts because of their superior catalytic activity and stability compared to non‐noble metals. Noble metal catalysts demonstrate efficient NOx conversion and high selectivity for N2. However, achieving high conversion, selectivity, and stability over a wide temperature range in the presence of excess O2, H2O, and SO2 remains a significant challenge. This review summarizes recent advancements in CO‐SCR over noble metal catalysts, providing insights for the development of CO‐SCR catalysts. This paper first examines the reaction mechanisms of CO‐SCR, followed by a discussion on the design and optimization strategies of noble metal catalysts, with a focus on composition and structural effects. This includes creating active metal sites, selecting appropriate supports, integrating catalytic additives, choosing monometallic nanoparticles, alloying, and using single‐atom catalysts. Finally, remaining challenges and potential avenues for future research have been suggested. The discovery of negatively charged noble metal single‐atom‐site catalysts presents new research opportunities.

An advanced high dimensional model representation approach for internal combustion engine modeling and optimization

This work introduces an efficient data-driven approach for engine performance modeling and optimization. A highly accurate and robust high-dimensional model representation (HDMR) surrogate model is developed based on the dataset generated from a coupled KIVA4-CHEMKIN Ⅱ software. The HDMR model is integrated with a multi-objective optimization algorithm, enabling the automatic identification of optimal combustion strategies. Results suggest that the constructed HDMR model is able to accurately predict the engine performance and exhaust gas emissions with negligible CPU costs. Moreover, the model effectively identifies optimal engine operating conditions, leading to enhanced fuel efficiency.

Efektifitas arang aktif tongkol jagung dalam menurunkan emisi kendaraan bermotor berbahan bakar ganda

Emission reduction through after treatment processes has become one of the options to minimize the adverse effects of two-wheeler emissions. Activated charcoal adsorbents have been proven effective in reducing emissions to a certain extent. In this study, corn cob charcoal activated with a 15% NaCl solution serves as the adsorbent. The adsorbent used is shaped into particles with a mesh size of 10. The adsorbent is placed in the modified motorcycle muffler. Testing is conducted on two-wheeled vehicles operated using the dual-fuel method, where biogas and pertalite are used as fuels. With this method, fuel concentrations are obtained significantly smaller compared to vehicles without emission reduction methods. Testing is carried out for 2 hours to determine the durability of the adsorbent in absorbing exhaust gas emissions. Based on the test results, where data collection is conducted every 10 minutes, the concentrations of emissions including hydrocarbons (HC), carbon monoxide (CO), and carbon dioxide (CO2) initially decrease and then rise again after several minutes. This indicates that the adsorbent effectively reduces emissions in a relatively short duration. However, the effectiveness of corn cob activated charcoal in reducing these three emissions varies, with the adsorbent showing good performance in reducing HC

Investigating the emissions and performance of ethanol and biodiesel blends on Al2O3 thermal barrier coated piston engine using response surface methodology design - multiparametric optimization

The Response Surface Methodology (RSM) optimization technique was used to examine the effect of load, Tomato Methyl Ester (TOME), and Ethanol injection enhanced diesel on engine performance and exhaust gas emissions with a normal piston and an Al2O3 coated piston. TOME biodiesel (10, 20, and 30%) and ethanol (10, 20, and 30%) were chosen to increase BTE while minimizing BSFC, NOx, CO, smoke, and HC. The RSM technique was used to operate the engine by load (0–100%). The results revealed that engine load, TOME, and ethanol concentration all exhibited a considerable effect on the response variables. The ANOVA results for the established quadratic models specified that for each model, an ideal was discovered by optimizing an experiment's user-defined historical design. The present research efforts to improve the performance of a diesel engine by using a thermal barrier-coated piston that runs on biodiesel blends. Al2O3 is the chosen material for TBC due to its excellent thermal insulation properties. B20E30 has a 4% higher brake thermal efficiency than diesel, but B10E20 and B30E20 mixes have a 3.6% and 12% reduction in BSFC. The B20 blends lowered CO and HC emissions by 6% and 8% respectively. In terms of performance and emissions, biodiesel blends performed similarly to pure diesel, and the combination was optimized through the design of an experiment tool.

Implementation of An Application-Based Motor Vehicle Exhaust Emission Level Detection System

Currently, air conditions on earth are getting worse over time due to the impact of air pollution. One example of air pollution is motor vehicle exhaust emissions. Exhaust gas emissions are the result of combustion residue in motor vehicle engines that use fuel. Motor vehicle exhaust emissions contain carbon monoxide (CO), hydrocarbons (HC), carbon dioxide gas (CO2) which have a negative impact on the environment and living creatures. This research will create a motor vehicle exhaust emission detection device. In this design, an Arduino microcontroller was used and the manufacture of this tool used an MQ-7 gas sensor to detect carbon monoxide (CO) gas, an MQ-2 sensor to detect hydrocarbon gas (HC), and an MQ-135 to detect carbon dioxide (CO2) gas. The emission test results will be sent to the application, this data includes plate number, vehicle type, vehicle brand, vehicle year and emission test results. The results of the carbon monoxide (CO) gas sensor calibration test taken from 5 data showed an error of 5.51%. The results of the hydrocarbon (HC) gas sensor calibration test taken from 5 data showed an error of 4.23%. The results of the carbon dioxide (CO2) gas sensor calibration test taken from 5 data showed an error of 1.06%. In the implementation of the tool and application, the test results were obtained for 15 vehicles. Where the highest hydrocarbon (HC) gas content value was 412 ppm, the highest carbon monoxide (CO) gas content value was 1.48%, and the highest carbon dioxide (CO2) gas content value was 21.4%.

Evaluating Engine Performance, Emissions, Noise, and Vibration: A Comparative Study of Diesel and Biodiesel Fuel Mixture

This study investigates the performance, emissions, noise, and vibration characteristics of a single-cylinder, air-cooled, four-stroke diesel engine running on pure diesel (D100) and biodiesel blends (B10: 90% diesel, 10% biodiesel; B20: 80% diesel, 20% biodiesel) at 1800 rpm, where the engine delivers maximum torque. Key metrics such as torque, power, brake specific fuel consumption (BSFC), exhaust gas temperature, noise, vibration, and emissions (CO, CO2, HC, O2, NOx, and smoke opacity) were analyzed. The findings indicate that B10 enhances torque, power output, and overall fuel efficiency, especially at low to medium loads, with a significant 17.54% reduction in BSFC compared to D100 at 40% engine load. Vibration levels generally increased with biodiesel addition, while B10 and B20 both reduced smoke opacity, with B20 having a more substantial effect. HC emissions decreased at idle with B10 but increased at higher loads, suggesting more complete combustion with potential thermal stress on engine components. Noise and vibration results were mixed; B20 reduced noise at higher loads but increased vibration. At 100% load, B20 decreased noise by 1.42% compared to D100. Despite benefits such as improved torque and reduced particulate emissions, biodiesel blends, particularly B20, led to increased NOx and CO2 emissions, emphasizing the need for further op-timization of blend formulations and emission control strategies. This study provides valuable insights into the tradeoffs and potential of biodiesel blends as sustainable diesel alternatives.

Методика оценки экологического эффекта от применения биотоплив

Purpose: the fight for ecology in the transport sector is ensured by improving the design of vehicles and engines, the working processes of internal combustion engines, as well as the use of alternative fuels. To determine the rational use of biofuels in vehicles, it is necessary to assess the environmental effect that will be achieved when using them. Methods: the existing methods of estimating exhaust gas emissions from motor vehicles are considered. Based on them, improvements have been made, which include the introduction of additional coefficients that take into account changes in the environmental load depending on the percentage of biofuels mixed with traditional hydrocarbon fuels. Results: the calculation of the environmental effect from the use of biofuels was carried out using the example of adding biodiesel to petroleum diesel fuel, for which, based on statistical data from the US Environmental Protection Agency and data, WE established dependences of changes in annual emissions of harmful substances and carbon dioxide for a heavy-duty cargo vehicle. In addition to the calculation, the article presents graphs of emissions of harmful substances, taking into account their relative aggressiveness and the amount of carbon dioxide released during the combustion of biodiesel mixtures. Practical significance: The proposed method for calculating the environmental effect makes it possible to estimate the volume of emissions of harmful substances and carbon dioxide depending on the concentration of biofuels mixed with traditional fuels. Such an approach can provide an overall picture of the effect of using biodiesel, and at the same time, the coefficients used need to be clarified.

Analisis Pengaruh Faktor Meteorologi Terhadap Konsentrasi Gas SO2 dan NO2 dari Cerobong Ketel Pabrik Gula X

The process of burning bagasse in a steam boiler produces pollutants in the form of exhaust gas emissions through the chimney, which can pollute air quality and harm health. The aim of this study is to determine the great influence of meteorological factors including exhaust gas temperature, air temperature, and flow speed in 4 areas of the boiler pipe that can affect the load of SO2 and NO2 gas pollutants through statistical data analysis. The ANOVA test used in this study was the ANOVA One Way test. The results of the study showed that there was a significant influence of the air temperature factor on SO2 in Boiler 4 / Cheng Chen with a value of F value 14,553 and a sig value of 0,032, as well as the influence that exists on the exhaust gas temperature factor and air temperature on NO2 in Stork Boiler 2 with an F value of 15,358 ; 17,889 and a sig value of 0.030 ; 0.024. The results of the analysis can be used as monitoring to evaluate the success rate and operational efficiency of the boiler under the management that has been carried out.

Application of the MAMCA Method in the Evaluation of Delivery Flows within City Centers: A Case Study of Rijeka

The aim of this paper was to propose a model for the evaluation of the flow of goods delivered to urban centers based on a systematic approach, generating possible scenarios of delivery activities and selecting those criteria for evaluation that contributed to the development of delivery activities and their evaluation by individual stakeholders. The number of users of delivery services is increasing, which leads to an increase in the volume of goods in the city center, creating additional traffic congestion—so-called bottlenecks—which results in an increased noise level and the emission of harmful exhaust gases, increasing dissatisfaction with the quality of life of the city population. It is, therefore, necessary for decision-makers to make a decision that achieves the best consensus among stakeholders. A test was carried out in the city of Rijeka. Based on a review of the literature and the spatial planning of the city of Rijeka, this paper proposed the following possible scenarios for the delivery of goods within the city center: status quo, delivery from one consolidation center, delivery from two consolidation centers, delivery by environmentally friendly vehicles from one consolidation center and livability. The criteria were evaluated by relevant stakeholders to determine the weight of each criterion for the development of goods deliveries in the city center. This paper used a multi-actor multi-criteria analysis (MAMCA) based on the optimization and ranking of scenarios in accordance with the given objective, the research problem, the defined criteria and the interests of the stakeholders. The solution of the MAMCA analysis evaluated the scenario with two consolidation centers best in accordance with the specified optimization objective.

An experimental investigation of the impacts of titanium dioxide (TiO2) and ethanol on performance and emission characteristics on diesel engines run with castor Biodiesel ethanol blended fuel

Investigating the impact of ethanol and TiO2 on the performance and emission characteristics of diesel engines running on a blend of ethanol and castor biodiesel is the primary goal of this study. The nanoparticles of ethanol, biodiesel, and TiO2 diesel fuel were combined at several concentrations. Diesel, B10, B20, B30, B10E10T, B20E10T, B30E10T, B10E20T, B20E20T, and B30E20T were among the various fuels that were investigated. The physiochemical properties of all the sample fuels were assessed, including density, pour point, cloud point, fire point, flash point, and kinematic viscosity. Following this, other engine performance indicators, such as torque, power, and fuel-consumption, were examined. Studies were also carried out on the properties of emissions, including CO, CO2, HC, and NO. Peak braking power and engine torque were found for each fuel under investigation at around 2750 and 2500 rpm, respectively. The addition reduced the brake-specific fuel consumption for B10E20T by 7.41 % while increasing the braking engine's torque and power by 8.64 and 3.86 %, respectively, in compared to blends without the TiO2 additions. When compared to diesel, the exhaust emission data without the addition of TiO2 revealed a decrease in CO and HC emissions but an increase in CO2 and NO emissions. On the other hand, using ethanol blend reduced NO emissions. According to the overall findings, diesel engine performance, combustion characteristics, and exhaust gas emissions were enhanced averagely by 7.43 % when a certain ratio of ethanol, biodiesel, and TiO2 additives (B10E20 + 50 ppm) was used.

The Impact of Container Ship Trim on Fuel Consumption and Navigation Safety

Fuel consumption, fuel cost savings, environmental pollution, and navigation safety are significant factors for shipping companies. Maritime transport represents 3% of total greenhouse gas emissions globally. Trim optimization is one of the ways to save energy and reduce ship emissions. Thus, this study aimed to evaluate how the optimization of the trim of container ships at different speeds can decrease exhaust gas emissions and fuel consumption while considering the safety of navigation. This research was conducted by calculating the fuel consumption in real conditions and calculating the optimal trim for different speeds and gases of a container ship of 11,400 TEU. All obtained results were statistically processed to analyze fuel consumption at various speeds, considering the ship’s trim. It turns out that savings should never be at the expense of navigation safety, especially in limited maneuvering areas, such as canals. When maneuvering in such places it is necessary to adjust the trim to ensure navigation safety, i.e., to improve the rudder and propulsion device response, instead of reducing fuel consumption

CRITERIA FOR ASSESSING THE EFFECTIVENESS OF TRANSPORT POWER PLANTS DECARBONISATION IN ACCORDANCE WITH IMPLEMENTATION OF THE SUSTAINABLE DEVELOPMENT CONCEPT

The directions of restoration and further development of the energy sector in Ukraine are considered in accordance with power plants with internal combustion engines, taking into account the widespread implementation of the Sustainable Development concept, which allows solving existing modern social, economic and environmental problems. For Ukraine, taking into account the economic opportunities and selected priorities for the chosen path of development, it is necessary at this time to choose gradual and specific directions to implement the Sustainable Development concept. The most priority areas of practical implementation of the concept are determined and it is indicated that the effectiveness of this implementation is associated with the development of the industry on the basis of the fourth and fifth industrial revolutions (Industry 4.0 and Industry 5.0). One of the main tasks in solving the problems of the concept is to ensure the environmental component. Notwithstanding the noted progress in improving the environmental efficiency of internal combustion engines, further attention needs to be paid to the task of spreading the introduction of “green energy”, i.e. decarbonisation – reducing greenhouse gas emissions into the environment (CO2). The issue of decarbonisation in the future should be given the greatest attention both in the development and in the manufacture and operation of engines. It is shown that the assessment of the impact of CO2 emitted with the exhaust gases of internal combustion engines into the environment is carried out taking into account the model of operation of engines and the justification of the introduced adjustments. A new criterion is proposed, which is called: “ICE criterion of environmental thermal pollution”, which is proposed for use in studies to assess the effectiveness of the implementation of decarbonisation strategies in all modes of transport at implementation of the Sustainable Development concept in global transport power plants. A method for determining the efficiency of physical and chemical processes of mixture formation and combustion in internal combustion engine cylinders is proposed when using hybrid fuel with “green hydrogen” as its component, which allows determining the dependence of hydrogen influence on the level of engines effective performance and formation of harmful emissions in exhaust gases.

Identification of the Problem in Controlling the Air–Fuel Mixture Ratio (Lambda Coefficient λ) in Small Spark-Ignition Engines for Positive Pressure Ventilators

The air–fuel ratio is a crucial parameter in internal combustion engines that affects optimal engine performance, emissions, fuel efficiency, engine durability, power, and efficiency. Positive pressure ventilators (PPVs) create specific operating conditions for drive units, characterized by a reduced ambient pressure compared to standard atmospheric pressure, which is used to control carburetor-based fuel supply systems. The impact of these conditions was investigated for four commonly used PPVs (with internal combustion engines) in fire services across the European Union (EU), using a lambda (λ), carbon dioxide (CO2), carbon monoxide (CO), and hydrogen carbon (HC) analyser for exhaust gases. All four ventilators were found to operate with lean and very lean mixtures, with their lambda coefficients ranging from 1.6 to 2.2. The conducted tests of the CO2, CO, and HC concentrations in the exhaust gases of all four fans show dependencies consistent with theoretical analyses of the impact of the fuel–air mixture on emissions. It can be observed that as the amount of burned air decreases, the values of CO and HC decrease, while the concentration of CO2 increases with the increase in engine load. Such an operation can accelerate engine wear, increase the emission of harmful exhaust gases, and reduce the effective performance of the device. This condition is attributed to an inadequate design process, where drive units are typically designed to operate within atmospheric pressure conditions, as is common for these engines. However, when operating with a PPV, the fan’s rotor induces significant air movement, leading to a reduction in ambient pressure on the intake side where the engine is located, thereby disrupting its proper operation.

Influence of AM Generated Burner Surface Roughness on NOx Emissions and Operability of Hydrogen-Rich Fuels

ABSTRACT The additive manufacturing (AM) technique enables the fabrication of advanced burner components to enhance the hydrogen capability of the existing gas turbines (GTs) and reduce the carbon footprints of the power generation sector. This technique produces rough surfaces that may require post-processing to maintain the desired functionality of a burner, particularly for hydrogen fuel with unique thermo-physical properties. This study, therefore, compared the stability of three swirlers of variable surface roughness manufactured using AM and traditional machining methods, with one of the AM swirler post-processed by grit-blasting. The comparison included a conventional benchmark (100% CH4), low carbon (23%volCH4/77%volH2) and zero carbon (100% H2) fuels across a range of equivalence ratios. Additionally, the study quantified the flame topology and emissions performance of the fuel blends for each swirler using high-speed OH* chemiluminescence and exhaust gas emissions measurements, respectively. The experimental investigation concluded that the AM-generated surface roughness within the considered range does not detrimentally impact NOX emissions and the stability of the fuel mix. However, the flame location was observed to be influenced by surface roughness and shifted more toward the vertical centerline of the burner with increased roughness. From the practical perspective, the results showed that post-manufacturing surface finishing offers negligible performance advantages, indicating potential cost reductions. It is recommended that further studies should investigate the influence of increased surface roughness on burner performance, as well as numerical modeling techniques which could provide an insight into when AM surfaces are likely to be more influential.

Inlet injection as an alternative, simplified method of hydrogen application in a miniature gas turbine

Hydrogen-powered gas turbines have great potential, because, among other things, they allow the elimination of the use of fuels containing carbon in their composition, which involves the elimination of CO2 emissions, which are a product of the combustion of hydrocarbon fuels. The paper presents the results of experimental research conducted on a miniature gas turbine co-powered by hydrogen gas. The aim of the research was to demonstrate the impact of the addition of hydrogen on the operation of the unit and exhaust gas emissions during hydrogen application in a way that does not require engine modification. This was accomplished by applying hydrogen gas through the turbine inlet. Hydrogen gas accounted for up to 0.91% of the total volume of gas flowing through the compressor, which resulted in hydrogen contributing almost 10% of the energy supplied to the engine in the form of fuel. The research focused on measuring fuel consumption, thrust, and temperature, as well as the composition of exhaust gases. The emission of carbon monoxide, nitrogen oxides and the concentration of oxygen and carbon dioxide were measured. The addition of hydrogen resulted in a reduction of the total mass of fuel consumed by over 18%. It led to a significant decrease in the temperature behind the combustion chamber with an increase in the amount of hydrogen applied. The addition of hydrogen also resulted in a reduction in CO2 concentration in exhaust gases by more than 30%, but at the same time, an increase in NOx emissions was recorded. The obtained results were compared with the results of tests presented in the literature, in which hydrogen was supplied to units of analogous structure in a classical way, i.e. directly to the combustion chamber.

Experimental Study of Natural Gas and Hydrogen Co-Firing Characteristics Using Different Types of Single Nozzles of F-Class Practical Gas Turbine Combustors

Abstract Recent research on co-firing natural gas and hydrogen, a carbon-free clean fuel, aims to reduce greenhouse gas emissions from aging gas turbine power generation, a key energy issue. This approach can enhance old gas turbines and increase the proportion of combined cycle power plant utilization as coal-fired power plants in Korea gradually shut down. This study seeks optimal operating conditions for mixed fuels without modifying the F-class gas turbine combustor. Experiments were conducted using four different types of fuel nozzles (F-Class DLN combustors) under varying loads and co-firing rates. The test used actual machine operating conditions from 30% to 100% thermal load, with hydrogen co-fired with natural gas up to 70% at each load. OH high-speed imaging and an OH-PLIF technique analyzed flame structure and characteristics. Dynamic pressure was measured to check combustion instability, and exhaust gas emissions were evaluated for combustion characteristics. Key findings include critical co-firing rates for each nozzle based on NOx emission levels and combustion dynamics. As the hydrogen co-firing rate increased, flame length decreased, and NOx levels rose rapidly beyond 30%vol. Dynamic pressure oscillations showed no significant variations compared to natural gas combustion. This study successfully derived a characteristic operation map for a single nozzle based on the hydrogen co-firing rate.

Numerical Study on Optimization of Combustion Cycle Parameters and Exhaust Gas Emissions in Marine Dual-Fuel Engines by Adjusting Ammonia Injection Phases

Decarbonizing maritime transport hinges on transitioning oil-fueled ships (98.4% of the fleet) to renewable and low-carbon fuel types. This shift is crucial for meeting the greenhouse gas (GHG) reduction targets set by the IMO and the EU, with the aim of achieving climate neutrality by 2050. Ammonia, which does not contain carbon atoms that generate CO2, is considered one of the effective solutions for decarbonization in the medium and long term. However, the concurrent increase in nitrogen oxide (NOx) emissions during the ammonia combustion cycle, subject to strict regulation by the MARPOL 73/78 convention, necessitates implementing solutions to reduce them through optimizing the combustion cycle. This publication presents a numerical study on the optimization of diesel and ammonia injection phases in a ship’s medium-speed engine, Wartsila 6L46. The study investigates the exhaust gas emissions and combustion cycle parameters through a high-pressure injection strategy. At an identified 7° CAD injection phase distance between diesel and ammonia, along with an optimal dual-fuel start of injection 10° CAD before TDC, a reduction of 47% in greenhouse gas emissions (GHG = CO2 + CH4 + N2O) was achieved compared to the diesel combustion cycle. This result aligns with the GHG reduction target set by both the IMO and the EU for 2030. Additionally, during the investigation of the thermodynamic combustion characteristics of the cycle, a comparative reduction in NOx of 4.6% was realized. This reduction is linked to the DeNOx process, where the decrease in NOx is offset by an increase in N2O. However, the optimized ammonia combustion cycle results in significant emissions of unburnt NH3, reaching 1.5 g/kWh. In summary, optimizing the combustion cycle of dual ammonia and diesel fuel is essential for achieving efficient and reliable engine performance. Balancing combustion efficiency with emission levels of greenhouse gases, unburned NH3, and NOx is crucial. For the Wartsila 6L46 marine diesel engine, the recommended injection phasing is A710/D717, with a 7° CAD between injection phases.

Comparison of Exhaust Gas Emissions of a Vehicle with an Internal Combustion Engine in High and Low Vehicular Congestion for a High Altitude City

Pollution generated by the automotive sector is one of the biggest concerns in the city of Quito. This is due to the fact that the majority of vehicles in the automotive fleet use fossil fuels as a source of propulsion energy. In addition, the heterogeneity of the technologies of the fuel injection systems means that the control of polluting emissions is highly limited. On the other hand, due to the high number of vehicles and the topographical characteristics of the city, high traffic congestion is generated during rush hours, producing abrupt changes in acceleration and reduction of stoichiometric mixtures. Based on the above, it was pertinent to compare the exhaust gas emissions that are produced in high and low vehicular congestion for a vehicle with an internal combustion engine Likewise, the correlations of the gases for both scenarios were determined. To do this, emissions were measured in a Mazda 3 vehicle on a major city route during rush hours and on weekends. A Kane Autoplus gas analyzer was used for exhaust gas measurement, and data logging was done on the Kane Live app. The results showed that in rush hours, the vehicle emits higher amounts of CO2, CO, and HC up to 0.7%; 128.5%; and 65.5%, respectively. There are moderate and strong correlations of O2-CO2 and CO-HC in high and low vehicular congestion, with Pearson’s correlation values greater than 0.5. Keywords: exhaust gases, internal combustion engine, pollution, route, rush hours, traffic. Resumen La contaminación generada por el sector automotriz, es uno de los mayores problemas que enfrenta la ciudad de Quito. Esto se debe a que la mayoría de vehículos del parque automotor, utilizan combustibles fósiles como fuente de energía de propulsión. Además, la heterogeneidad de las tecnologías de los sistemas de inyección de combustible, hace que el control de emisiones contaminantes se limite considerablemente. Por otro lado, debido al elevado número de vehículos y a las características topográficas de la ciudad, se genera una elevada congestión vehicular en horas pico, produciendo cambios abruptos de aceleraciones y reducción de las mezclas estequiométricas. Con base a lo expuesto, fue pertinente comparar las emisiones de gases de escape que se producen en alta y baja congestión vehicular para un vehículo con motor de combustión interna, y así mismo, se determinó las correlaciones de los gases para ambos escenarios. Para ello, se midió las emisiones en un vehículo Mazda 3 sobre una ruta importante de la ciudad en horas pico y fines de semana. Se utilizó un analizador de gases Kane Autoplus para la medición de los gases de escape, y el registro de datos se efectuó en la aplicación Kane Live. Los resultados mostraron que en horas pico, el vehículo emite mayores cantidades de CO2, CO, HC de hasta el 0,77%; 6,66%; 94,69%, respectivamente. Existen moderadas y fuertes correlaciones de O2-CO2 y CO-HC en alta y baja congestión vehicular, con valores de correlación de Pearson superior a 0,5. Palabras Clave: contaminación, gases de escape, horas pico, motor de combustión interna, ruta, tráfico.