Carbon Nitrogen Dioxide Research Articles

Effects of High-Density Polyethylene (HDPE) and Additives Fuel Blends on Diesel Engine’s Performance and Emissions and NOx Prediction using Boosted Tree Model

The rising demand for eco-friendly and sustainable fuel options has prompted the investigation of alternative energy sources. This study explores the use of blends of High-Density Polyethylene (HDPE), and 7% biodiesel (B7) with additives as a substitute for diesel fuel. The research involves comparing three different mix ratios of HDPE and additives with a conventional B7 blend: a control of 100% B7, a mix of 90% B7 with 10% HDPE, and a blend of 85% B7 with 10% HDPE and 5% additives. Fourier Transform Infrared (FTIR) spectroscopy was employed to identify the fuels' functional groups. The study also measured key performance metrics, including brake-specific fuel consumption (BSFC), brake power (BP), and exhaust emissions of nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons (HC), and carbon dioxide (CO2). A Boosted Tree Model was used to establish a prediction and analysis of NOx emissions. The findings indicate that incorporating additives into the HDPE blend positively influences both engine performance and emissions. The combination of HDPE and additives with B7 resulted in reduced emissions across various engine loads and speeds, decreasing hydrocarbon and carbon-containing emissions. The Boosted Tree Model, with a configuration of 4 leaf nodes, demonstrated strong predictive accuracy, with a coefficient of determination (R2) of 0.86 and a root-mean-square error (RMSE) of 0.38 for the training dataset, and R2 of 0.97 with RMSE of 0.16 for the validation dataset. The study underscores the benefits of integrating HDPE and additives into diesel blends, highlighting their potential to lower emissions and supporting the search for viable alternative fuels.

Fundamental representation of the amount of substance fraction of carbon dioxide in nitrogen according to the dynamic volumetric principle

Abstract The new Austrian primary standard for the amount of substance fraction of carbon dioxide in nitrogen is presented. The primary standard is working according to the dynamic volumetric principle and is a fundamental representation of the measurement quantity. The direct traceability to the basic SI units is thereby thermodynamically realized without an artefact. A complete measurement uncertainty budget is calculated and verified with a bilateral inter-laboratory comparison.

Adaptive Control of Ships’ Oil-Fired Boilers Using Flame Image-Based IMC-PID and Deep Reinforcement Learning

The control system of oil-fired boiler units on ships plays a crucial role in reducing the emissions of atmospheric pollutants such as nitrogen oxides (NOx), sulfur dioxides (SO2), and carbon dioxide (CO2). Traditional control methods using conventional measurement sensors face limitations in real-time control due to response delays, which has led to the growing interest in combustion control methods using flame images. To ensure the precision of such combustion control systems, the system model must be thoroughly considered during controller design. However, finding the optimal tuning point is challenging due to the changes in the system model and nonlinearity caused by environmental variations. This study proposes a controller that integrates an internal model control (IMC)-based PID controller with the deep deterministic policy gradient (DDPG) algorithm of deep reinforcement learning to enhance the adaptability of image-based combustion control systems to environmental changes. The proposed controller adjusts the PID parameter values in real-time through the learning of the determination constant lambda (λ) of the IMC internal model. This approach reduces computational resources by shrinking the learning dimensions of the DDPG agent and limits transient responses through constrained learning of control parameters. Experimental results show that the proposed controller exhibited rapid adaptive performance in the learning process for the target oxygen concentration, achieving a reward value of −0.05 within just 105 episodes. Furthermore, when compared to traditional PID tuning methods, the proposed controller demonstrated superior performance, achieving a target value error of 0.0032 and a low overshoot range of 0.0498 to 0.0631, providing the fastest response speed and minimal oscillation. Additionally, experiments conducted on an actual operating ship verified the practical feasibility of this system, highlighting its potential for real-time control and pollutant reduction in marine applications.

Exergy and exergoeconomic analysis of a hybrid airborne wind and solar energy system for power, liquid nitrogen and carbon dioxide production

Airborne wind energy (AWE) systems have emerged as cost-effective and sustainable solutions that have not yet been coupled with solar technologies and integrated power plants to produce energy and on-demand substances. This study proposes an integrated system driven by an innovative AWE and photovoltaic (PV) hybrid system. This combination can harness stronger and more stable wind energy while decreasing system costs and power intermittency. The proposed system combines seven subsystems, including AWE, PV, air separation unit, oxyfuel power plant, absorption refrigeration, a nitrogen liquefaction process, and Organic Rankine Cycle (ORC) to simultaneously generate power, liquid nitrogen, and liquid carbon dioxide. The hybrid AWE-PV system can generate 10.8 MW power to initiate the system to produce 55 MW power, 127.2 m3/h liquid nitrogen, and 98.4 m3/h liquid carbon dioxide. The exergy analysis has been conducted, showing maximum exergy destruction in heat exchangers, and the total exergy efficiency of the integrated structure reaches 90.21 %. The exergoeconomic analysis illustrates that the maximum capital cost occurs in compressors and turbines with a percentage of 51 % (∼4600 $/h) and 26 % (∼2400 $/h), respectively. This first demonstration of implementing hybrid AWE-PV renewable energy sources in an integrated structure can open new perspectives and avenues toward using AWE and its combination with other renewable energy sources in the future.

Exploring high-emission driving behaviors of heavy-duty diesel vehicles based on engine principles under different road grade levels

To reveal the outstanding high-emission problems that occur when heavy-duty diesel vehicles (HDDV) pass uphill and downhill, this study proposes a method to depict the nitrogen oxides (NOx) and carbon dioxide (CO2) high-emission driving behaviors caused by slopes from the perspective of engine principles. By calculating emission and grade data of HDDV based on on-board diagnostic (OBD) data and digital elevation model (DEM) data, the 262 short trips including uphill, flat-road and downhill are firstly obtained through the rule-based short trip segmentation method, and the significant correlation between the road grade and emissions of the short trips is verified by Kendall's Tau and K-means clustering. Secondly, by comparing the distribution changes of three speed categories (acceleration state, constant speed state and deceleration state), the differences in HDDV operating states under different grade levels are discussed. Finally, the machine learning models (Random Forest, XGBoost and Elastic Net), are used to develop the NOx and CO2 emission estimation model, identifying high-emission driving behaviors, particularly during uphill driving, which showed the highest proportion of high-emission. Explained by the feature importance and SHapley Additive exPlanations (SHAP) model that large accelerator pedal opening, frequent aggressive acceleration, and high engine load have positive effects both on NOx and CO2 emissions. The difference is in the air-fuel ratio that the engine in the rich or slightly lean burning state will increase CO2 emissions and the lean burning state will increase NOx emissions. In addition, due to the uncertainty of the actual uphill, drivers often undergo a rapid “deceleration-uniform-acceleration” process, which significantly contributes to high NOx and CO2 emissions from the engine perspective. The findings provide insights for designing driving strategies in slope scenarios and offer a novel perspective on depicting driving behaviors.

Technology of estimating nitrogen dioxide and carbon dioxide emissions by large industrial centers of Western Siberia

Technology of estimating nitrogen dioxide and carbon dioxide emissions by large industrial centers of Western Siberia

Compact Pollution Control and Sound Indicator Device

Abstract: The increasing urbanisation of cities globally has intensified worries about car pollution, leading to substantial environmental damage and public health risks. Current Pollution Under Control (PUC) systems, which primarily focus on reducing exhaust emissions, often encounter usability problems and neglect the issue of noise pollution. This study presents a new and innovative approach called the Compact Pollution Control and Sound Indicator Device (CPCSID), which aims to overcome these limitations. The project includes state-of-the-art sensors capable of discriminating and measuring several exhaust gases generated by cars, including nitrogen oxides (NOx), carbon monoxide (CO), and carbon dioxide (CO2). Additionally, it contains an integrated microphone to assess engine-generated noise levels. The LCD panel presents real-time data of pollution and noise, providing consumers with practical insights into the environmental effects of their car. In addition, our invention is integrated with a GSM module, which allows it to send SMS notifications to car owners. These warnings aim to promote environmentally aware behaviour and enable quick responses to reduce pollution. The small size and easy-to-use design make it suited for both individual car owners and fleet managers, providing a complete solution for reducing automobile pollution in urban areas.

Potential of Methane (CH4), Nitrogen (N2), and Carbon Dioxide (CO2) from Eco-Enzyme with the Addition of Cow Feces Starter

Eco-enzyme solutions are generally used in the manufacture of disinfectants, floor cleaners, liquid fertilizers, preservatives and others. In this study, eco-enzyme was used as the main ingredient in the manufacture of biogas fermentation with the addition of cow feces as an additional starter in the fermentation. The aim of this study was to determine the content of CH4, CO2, N2, pH, temperature, and pressure in eco-enzyme fermentation with the addition of cow feces starter. his research is a quantitative research with the type of experimental research as well as direct observation data collection techniques and data analysis techniques using descriptive statistical analysis. The results showed that the treatment that produced the highest methane (CH4) gas was the P5 treatment with a concentration of 2.889%. 6,1. The highest volume pressure value was produced in the P5 treatment which was 70 ml. Nitrogen gas (N2) and carbon dioxide gas (CO2), the concentration of nitrogen gas (N2) from reactor P0 - P4 is in the range of 95.875-99.669 % and the concentration of carbon dioxide (CO2) from reactor P0 - P4 is in the range of 0.237 - 4.125 %.

Effect of exhaust gas recirculation on the performance and emission characteristics of diesel engine with hydrogen fuel and nano additives

One of the most popular techniques for reducing emissions, in particular nitrogen oxide (NOX), carbon monoxide (CO), carbon dioxide (CO2), and particulate matter (PM), is exhaust gas recirculation (EGR). In an EGR system, the intake manifold is used to re-introduce some of the exhaust gases into the combustion chamber. Diesel engine performance could be enhanced by employing the right number of nano additives. Nano additions aid in increasing efficiency when using hydro fuel. The following systems are impacted by the use of EGR: brake specific fuel consumption (BSFC), diesel engine combustion characteristics, brake thermal efficiency (BTE), engine speed, CO2 and HC emissions, turbocharged diesel engine performance characteristics, fuels, temperature, and on EGR.

ALPHA-KETOGLUTARATE INDUCES NUCLEAR RECEPTORS RATHER THAN NRF2 IN THE FRUIT FLY Drosophila melanogaster

Aim. To test whether expression of Nrf2 targets in the fruit fly Drosophila melanogaster are activated by diet supplemented with alpha-ketoglutarate (AKG). Methods. The Canton-S strain of D. melanogaster was used in the study. Female flies were reared in demographic cages (150 flies per group) on the medium containing 5% sucrose, 5% yeast, 1.2% agar, 0.18% nipagin. Experimental diet was supplemented with 10 mM disodium salt of AKG. The flies were reared during 21 days and after that were anesthetized with carbon dioxide and snap-frozen in liquid nitrogen for further biochemical studies. Expression of genes Ugt37A2, GstD2, and Cyp6a2, coding for a uridine diphosphate glycosyltransferase family 37 member A2, glutathione S-transferase D2, and cytochrome P450 6a2, respectively, respectively, was analyzed using semi-quantitative reverse transcription polymerase chain reaction followed by visualization of the products in agarose gel. The gene Tbp (TATA-box binding protein) was used as a reference gene. Results. Flies fed AKG-supplemented diet during 21 days had 2.8-fold higher level of the Cyp6a2 expression than control flies. At the same time, AKG-supplemented food did not affect expression of Ugt37A2 and GstD2 genes. Conclusions. Continuous consumption of AKG-supplemented food results in the increase in the levels of messenger ribonucleic acid of Cyp6a2 gene, a target of transcriptional factors Nrf2 and DHR96, but not Ugt37A2 and GstD2 genes. Since expression of the latter two genes was unaffected by AKG-supplemented diet, it indicates that AKG may influence other transcriptional regulators, such as nuclear receptors that have common targets with Nrf2.

Optimal planning and designing of microgrid systems with hybrid renewable energy technologies for sustainable environment in cities.

Although hybrid wind-biomass-battery-solar energy systems have enormous potential to power future cities sustainably, there are still difficulties involved in their optimal planning and designing that prevent their widespread adoption. This article aims to develop an optimal sizing of microgrids by incorporating renewable energy (RE) technologies for improving cost efficiency and sustainability in urban areas. Diverse RE technologies such as photovoltaic (PV) systems, biomass, batteries, wind turbines, and converters are considered for system configuration to obtain this goal. Net present cost (NPC) is this study's objective function for optimal sizing microgrid configuration. For demonstration, we assess the technical, economic factors, and atmospheric emissions of optimal hybrid renewable energy systems for Putrajaya City in Malaysia. The required solar radiation data, temperature, and wind speeds are collected from the NASA surface metrological database. From the quantitative analysis of simulations, the biomass-battery-based system has optimal economic outcomes compared to other systems with an NPC of around 1.07M$, while the cost of energy (COE) is 0.118 $/kWh. Moreover, environmentally safe nitrogen oxide emissions, carbon monoxide, and carbon dioxide concentrations exist. The grid-tied RE technology boasts cost-effectiveness, with an NPC of 348,318 $ and a COE of 0.0112 $/kWh. This study aids decision-makers in formulating policies for integrating hybrid RE systems in urban areas, promoting sustainable energy generation.

Investigating the Effects of Environmentally Friendly Additives on the Exhaust Gas Composition and Fuel Consumption of an Internal Combustion Engine

This article shows the effect of the addition of effective microorganisms and silver on the exhaust gas composition and fuel consumption. Exhaust emission standards are becoming increasingly stringent, which makes it difficult for engine manufacturers to meet them. For this reason, intensive work is underway to use alternative propulsion systems on ships, and for diesel engines, alternative fuels. Among other things, this applies to mixtures of petroleum-based fuels with vegetable oils and their esters. Unfortunately, their use, due to their physicochemical properties, can negatively affect the performance of the engine and the wear of its components. Therefore, the aim of this study was to see how additives of effective microorganisms in the form of ceramic liquid and tubes, and a silver solution and colloidal silver would affect some engine parameters, including the exhaust gas composition and fuel consumption. The authors are not aware of the results of previous research on this issue. The tests were carried out on a diesel engine for four types of green additives at concentrations of 2% and 5%, at different ranges of its load. The additives added to the diesel fuel were characterised, and the test stand was presented, along with the parameters of the tested fuel. The effect of additives on selected engine parameters, including fuel consumption, was presented. The characteristics of hourly fuel consumption and selected components of the exhaust gas, including nitrogen oxides, carbon monoxide and carbon dioxide as a function of the concentration of ecological additives are shown and analysed. It was found that the most beneficial additive that had a positive effect on the exhaust gas composition and fuel consumption was a silver solution in a 2% concentration. There was a decrease of up to 4% in the NOx content of the exhaust gas, a decrease in carbon monoxide of more than 28%, a decrease in carbon dioxide of 4.6% and a decrease in fuel consumption of around 3% was achieved under the tested conditions. The use of these additives is an innovative solution that has a positive impact on reducing the emissions of harmful compounds into the atmosphere. In further research, it will be necessary to study the effect of this additive on the combustion process in the engine and the wear of its components, as well as to confirm the results obtained in real operating conditions.

Investigation of the effects of single and double-walled carbon nanotube utilization on diesel engine combustion, emissions, and performance

In this study, single-walled carbon nanotubes (SWCNT) and double-walled carbon nanotubes (DWCNT) were separately added to diesel fuel to investigate their effects on the combustion, performance, and emission characteristics of a diesel engine. SWCNT and DWCNT were added to diesel fuel at concentrations of 100 mg/L with the assistance of ultrasonication, resulting in the creation of DFCNT-1 and DFCNT-2 fuels. Fuel samples were tested at 1500 rpm under varying load conditions. The results indicated significant increases in combustion parameters such as cylinder pressure (CP), Net Heat Release Rate (NHRR), Rate of Pressure Rise (ROPR), Cumulative Heat Release (CHR), and average gas temperature (MGT) for DFCNT-1 and DFCNT-2 fuels. Additionally, the use of DFCNT-1 and DFCNT-2 fuels led to a decrease in carbon monoxide and smoke emissions while nitrogen oxide and carbon dioxide emissions increased. The Brake Specific Fuel Consumption (BSFC) decreased by 7.59% and 4.29% with the use of DFCNT-1 and DFCNT-2, respectively. Moreover, a shorter ignition delay (ID) and combustion duration (CD) were observed with DFCNT-1 and DFCNT-2 fuels. Overall, it was concluded that the addition of SWCNT was more effective than DWCNT in terms of combustion efficiency, performance, and emissions.

The Experimental Investigation of the Effects on the Combustion, Performance, and Emission Characteristics of an RCCI Engine Using Methanol/Diesel Fuel

Reactivity-controlled compression ignition (RCCI) combustion is considered one of the most promising low-temperature combustion (LTC) concepts aimed at reducing greenhouse gases for the transportation and power generation sectors. RCCI combustion mode is achieved by combining different fuel types with low and high temperatures. The aim of this study is to investigate combustion characteristics and reduce nitrogen oxide (NOx) and carbon dioxide (CO2) emissions. In this experimental study, the effects of the RCCI strategy using methanol/diesel fuel on combustion characteristics (ignition delay, combustion duration), engine performance (brake-specific fuel consumption and brake-specific energy consumption), and emissions were examined in a four-cylinder, turbocharged, dual-fuel engine. The experiments were conducted at a constant speed of 1750 rpm at partial loads (40 Nm, 60 Nm, 80 Nm, and 100 Nm). The test results obtained with diesel fuel were compared with the test results obtained with methanol at different mass flow rates. When the results were examined, the minimum ignition delay (ID) occurred at 40 Nm torque, 5.63 crank angle (CA) with M12 fuel, while the maximum ID occurred with M26 fuel at 80 Nm torque, showing an increasing trend as engine load (EL) increased. The highest combustion time (CD) was achieved with M26 fuel at 100 Nm torque, whereas the lowest was achieved with the same fuel (M26) at 40 Nm. While the minimum brake-specific fuel consumption (bsfc) was 45.9 g/kWh for conventional diesel fuel at 40 Nm, the highest bsfc was 104.88 g/kWh for 100 Nm with M26 fuel. Generally, bsfc tends to increase with increasing load. Brake-specific energy consumption (bsec) had the lowest value of 1950.58 kJ/kWh with conventional diesel fuel at 40 Nm and the highest value of 4034.69 kJ/kWh with M26 fuel at 100 Nm. As the methanol content increased, significant improvements were observed in (NOx) and (CO2) emissions, while hydrocarbon (HC) and oxygen (O2) emissions increased as well. Smoke emissions decreased at low loads but tended to increase at high loads.

Production of ammonium bicarbonate from the condensate of the upgrading biogas-pipelines

Developing a suite of biofuels for different applications relies heavily on upgrading technologies to remove nitrogen compounds and carbon dioxide. Particularly in the upgrading of biogas to biomethane, simple water scrubbing is the most widely used technology for biogas upgrading. This technology can be synergistically implemented without the need for additional equipment for processing steps, although this design has not been conceived yet. Samples of biogas-pipeline condensates were collected from 3 different anaerobic digestion plants processing 3 different feedstocks (i.e., food waste, agrowaste, and manure) at 3 different locations in each plant (i.e., biodigester and postdigester condensate pits, digestate pasteurizer, and biogas booster and chiller). The methodology for the analysis of the 5-mL biogas-pipeline condensates was acid-base titration with 0.06 M hydrochloric acid and 0.13 M sodium hydroxide solutions as titrants, and induction of crystallization by cooling at 3 °C, adding up to 40 mL of acetone as antisolvent, and settling for 12 h. The results showed that the concentration of ammonium bicarbonate in the condensates ranged from 0.75 to 50 g/L. The most suitable location to enhance the upgradation of biogas, formation of condensate, and precipitation of ammonium bicarbonate was the pit after the anaerobic digester and before the biogas storage. The most concentrated condensate was retrieved from the biogas-pipeline coming out of the pasteurization tank, but the operation at 70.5 °C also led to volatilization of organic compounds that negatively affected the biogas quality. Future work aims to investigate coating and granulation of ammonium bicarbonate crystals to improve their stability and commercialization.

Experimental investigation on pyrolysis products and pore structure characteristics of organic-rich shale heated by supercritical carbon dioxide

The efficient pyrolysis and conversion of organic matter in organic-rich shale, as well as the effective recovery of pyrolysis shale oil and gas, play a vital role in alleviating energy pressure. The state of carbon dioxide (CO2) in the pyrolysis environment of shale reservoirs is the supercritical state. Its unique supercritical fluid properties not only effectively heat organic matter, displace pyrolysis products and change shale pore structure, but also achieve carbon storage to a certain extent. Shale samples were made into powder and three sizes of cores, and nitrogen (N2) and supercritical carbon dioxide (ScCO2) pyrolysis experiments were performed at different final pyrolysis temperatures. The properties and mineral characteristics of the pyrolysis products were studied based on gas chromatography analysis, X-ray diffraction tests, and mass spectrometry analysis. Besides, the pore structure characteristics at different regions of cores before and after pyrolysis were analyzed using N2 adsorption tests to clarify the impact of fracturing degree on the pyrolysis effect. The results indicate that the optimal pyrolysis temperature of Longkou shale is about 430 °C. Compared with N2, the oil yield of ScCO2 pyrolysis is higher. The pyrolysis oil obtained by ScCO2 extraction has more intermediate fractions and higher relative molecular weight. The ScCO2 can effectively improve the pore diameter of shale and its effect is better than that of N2. The micropores are produced in shale after pyrolysis, and the macropores only are generated in ScCO2 pyrolysis environments with temperatures greater than 430 °C. The pore structure has different development characteristics at different pyrolysis temperatures, which are mainly affected by the pressure holding of volatile matter and products blocking. Compared to the surface of the core, the pore development effect inside the core is better. With the decrease in core size, the pore diameter, specific surface area, and pore volume of cores all increase after pyrolysis.

Comparative analysis of compression ignition engines performance and emission characteristics devouring edible and nonedible oil biodiesel

AbstractThe globe is in search for an upgraded and compatible alternative of diesel to triumph over pollution and its limited availability issues. Researchers are using biodiesel from various edible and non‐edible oil sources to reduce environmental footprint of diesel. This article compares the performance and emission characteristics of diesel engines fueled by edible and non‐edible oil biodiesel. In this work, five biodiesels (methyl esters of microalgae, jatropha, karanja, soybean, and sunflower) are tested and transesterification is used to produce methyl esters to optimize their physiochemical properties. It is observed that all the properties lie in tolerance limits. To examine the compatibility of the proposed methyl esters two performance characteristics, brake thermal efficiency and brake specific fuel consumption are examined. Further, the emission characteristics such as nitrogen oxides, carbon monoxide, hydrocarbons, and carbon dioxides are investigated. To validate results the blend characteristics are compared to diesel. The relative analysis revels that the brake thermal efficiency is declined by 8.87% as compared to diesel whereas the brake specific fuel consumption is increased by 4.28%. The carbon monoxide and hydrocarbon levels are decreased by 7.32% and 20.56% whereas nitrogen oxides and carbon dioxide levels are increased by 7.47% and 4.80%, respectively. The analysis infers that microalgae biodiesel gives adequately better characteristics.

Response Analysis of an Experimental Study on the Effect of Speed and Premixed Fuel Ratio on Performance and Emissions in RCCI Engine

Even though CI engines are more efficient than SI engines due to their ability to operate at a greater compression ratio, a leaner charge, and lower throttle losses, they have higher PM and nitrogen oxide emissions. The induction system modification with fuel port injection is used as a parameter in RCCI engine operations for controlling emission through in-cylinder charge reactivity and combustion phasing. By varying the amount of hydrous bioethanol in the premixed fuel injection ratio, the engine’s performance and emissions are greatly affected. In this study, an experimental investigation of a triple-fuel RCCI engine running on port-injected gasoline-bioethanol blend and direct-injected diesel fuel was conducted. Taguchi’s experimental design method was employed to assess the impact of various independent variables utilizing three set levels and two factors with the L9 orthogonal array. From the findings, the delta value shows the highest average response for each factor. Engine speed has the largest effect on the signal-to-noise ratio (SNR) with the (delta value of: 10.7446, rank = 1), and the delta value of 38.96, rank = 1, has the largest effect on the response of means at engine speeds of 3000 rpm. The premixed fuel ratio of G25BE75 (delta: 87.30, rank = 1) has the largest effect on the standard deviation. The lines are not parallel in all emission and performance cases except for Tb and CO2, which are close to parallel. The best means in engine speed and premixed blended fuel ratio were NOx, CO, HC, and brake power. At 3000 rpm, the speed had the larger main effect plots of SNR. The premixed fuel ratio of G25BE75 had higher main effect plots for means and standard deviations. The residues appear to have been dispersed normally based on a straight line by using a normal probability plot. The data are normally distributed, as demonstrated by the normal probability plot, and the factors had an impact on the response. Conferring to the experiment result, a high engine speed and higher ethanol content in the RCCI premixed fuel are preferred for reducing nitrogen oxides (NOx) and carbon dioxide (CO2), while unburned hydrocarbons (UHCs) and carbon monoxide (CO) showed a slight increase.

Environmental Benefits of Transition to Electric School Buses

The research paper titled Environmental Benefits of Transition to Electric School Buses examines the substantial environmental and public health advantages of replacing diesel-powered school buses with electric school buses (ESBs) in the United States. With over 500,000 school buses transporting around 27 million students daily, more than 90% of them rely on diesel engines, which emit harmful pollutants such as nitrogen oxides (NOx), particulate matter (PM), and carbon dioxide (CO2). These pollutants contribute to air pollution, climate change, and serious health issues, particularly for children who are more vulnerable to the harmful effects of diesel exhaust. This paper explores the environmental impacts of diesel school buses, including their contribution to greenhouse gas emissions, and highlights the disproportionate effects on disadvantaged communities, which are often located near highways or bus depots where pollution is concentrated. Diesel emissions contribute to climate change through the release of CO2 and black carbon, a potent climate-forcing agent. The paper also emphasizes the health risks associated with diesel exhaust, such as respiratory diseases and increased asthma rates, particularly among children. The transition to ESBs offers a promising solution to these issues. ESBs produce zero tailpipe emissions, reducing NOx, PM, and CO2, which directly improves air quality and lowers greenhouse gas emissions. Additionally, the use of ESBs can significantly reduce the incidence of respiratory problems, improve overall student health, and lead to better academic performance due to fewer absences caused by illness. Beyond environmental and health benefits, ESBs can play a crucial role in advancing climate action by cutting emissions, especially when powered by renewable energy sources. As school districts across the U.S. explore the adoption of electric school buses, the research highlights the transformative potential of ESBs in creating a cleaner, healthier, and more equitable future for children and communities alike.

Carbon neutrality with ammonia: An analysis of its feasibility as a fuel for diesel engines fuelled with spirulina microalgae and oxygenated additives

Ammonia has emerged as a promising gaseous fuel for replacing conventional fossil fuels and achieving carbon neutrality. This research explores the viability of using ammonia as a fuel in compression ignition diesel engines operating in dual-fuel mode. The study investigates the performance and emission characteristics of diesel engines fueled with ammonia, microalgae-based biodiesel, and their combinations, with the addition of Fe2O3 nanoparticles to enhance combustion efficiency. A series of experiments were conducted using various blends of ammonia, biodiesel, and nanoparticles in a single-cylinder engine. The objective was to assess the impact of ammonia and biodiesel on thermal efficiency and carbon-based emissions. Comparative analysis revealed that ammonia-based fuels exhibited higher brake thermal efficiency and lower carbon emissions compared to traditional diesel fuel. The combination of ammonia, biodiesel, and nanoparticles resulted in an 8.5% increase in thermal efficiency compared to diesel fuel. However, the fuel consumption increased by 18% due to the lower energy density and higher viscosity of the biodiesel blends. Furthermore, the study examined the emissions profile of the tested fuels. The use of ammonia and nanoparticles led to significant reductions in carbon monoxide, hydrocarbon, and smoke emissions. However, there was a slight increase in nitrogen oxides and carbon dioxide emissions, regardless of engine loading conditions. It was observed that the emission of NOx was influenced by combustion delay and autoignition temperature. To mitigate NOx emissions, optimizing the combustion delay and avoiding premixed combustion phases are crucial. Based on the findings, the study concludes that ammonia has the potential to serve as a viable substitute for diesel fuel in engines. Ammonia-based fuels exhibit higher brake thermal efficiency and lower carbon emissions. Future research should focus on optimizing combustion parameters to minimize NOx emissions, thereby facilitating the widespread adoption of ammonia in diesel engines and contributing to the decarbonization of the transportation sector.