Atmospheric Pollutant Emissions Research Articles

Estimates of Air Pollutant Emissions by Vehicle Fleet in the State of Pará, Brazil: Impacts and Trends

Objective: aims to estimate emissions of the main atmospheric pollutants from vehicular sources in the state of Pará, to continue the environmental agenda of monitoring air quality. Theoretical Framework: The growing global concern about air quality in urban areas is driven by the environmental and public health impacts caused by air pollution. The concentration of pollutants from vehicle sources represents one of the main challenges, especially in densely populated regions such as the capital and other major cities in the state of Pará, where the automotive fleet has increased significantly. Method: The methodology used combined "bottom-up" and "top-down" methods to calculate emissions of carbon monoxide (CO), nitrogen oxides (NO) and total hydrocarbons (HC) for different vehicle categories and fuel types. Data on licensed vehicle fleets and fuel consumption obtained from DETRAN-PA and ANP were used. Results and Discussion: The results revealed that gasoline-powered vehicles are responsible for the majority of CO and HC emissions, while diesel vehicles emit the largest amounts of NO into the atmosphere. Motorcycles were identified as the largest source of emissions due to their larger number in the circulating fleet. Our results also highlight the importance of assessing and monitoring vehicle emissions to develop effective air pollution control strategies. Research Implications: The information obtained in this study is unprecedented for the study area, and can therefore support the formulation of environmental policies aimed at reducing emissions of atmospheric pollutants in the state of Pará, thus promoting an improvement in air quality and public health. Originality/Value: This paper makes an unprecedented contribution to national and international literature on environmental pollution in large urban centers. On the eve of the largest climate and environment conference on the planet (COP30) to be held in Pará, Amazonas, this research joins efforts in relation to the monitoring, forecasting and mitigation of air pollution, considered one of the main environmental problems of today.

Zn Isotope Tracing Unveils Primary Anthropogenic Zn Sources in Glacial Cryoconite of the High Asian Mountains

AbstractZinc (Zn) exerts a significant influence on the global environment, terrestrial ecosystems, and human health. The application of Zn isotopes (δ66Zn) has been suggested as a potent tool for tracing environmental contamination. However, studies focusing on Zn isotope tracing within the cryosphere areas are notably limited. Here we present the first data set on Zn isotopes in glacial cryoconite, based on observations over a large regional scale in High Asian Mountains (including Tibetan Plateau (TP) and its surroundings of western China). The results showed that glacial cryoconite had a general heavy Zn isotopic signature in various TP locations, with δ66Zn values ranging from −0.22‰ to +0.87‰. Employing the MixSIAR model, the overall Zn contribution source to the cryoconite was mineral dust (36%) > coal burning (33%) > non‐exhaust traffic emissions (22%) > industrial smelting (10%). We ascertained that anthropogenic sources account for the primary contribution (about 60%–73%) of Zn inputs in all glacial locations, with coal burning emerging as the foremost anthropogenic contributor (mean 33%). Anthropogenic Zn in various TP locations was primarily derived from Zn emissions resulting from coal combustion, though it is also predominantly influenced by industrial smelting source in cryoconite of the Tianshan Mountains. Our results aligned with coal combustion data from the energy inventory of western China, suggesting that regional coal burning likely represents the foremost source of atmospheric Zn pollutant emission and deposition in the High Asia mountain glaciers.

Path of Co-control of Pollution and Carbon Emissions Reduction in Typical Parks of Pharmaceutical and Health Industry in Beijing

The agglomeration of carbon emissions from the pharmaceutical and health industry has been growing gradually in Beijing. Conducting research on the path of co-control of pollution and carbon emission reduction in industrial parks is essential to realize synergy between economic development, pollution reduction, and green low-carbon. Based on the production activity data in 2020 of two typical parks of manufacturing and R&D, we selected six measures for co-control of pollution and carbon emission reduction and set up a synergistic development scenario to explore the collaborative development path of different types of parks. The results showed that： ① The primary carbon emission source in the two parks was energy consumption, such as natural gas and electricity, whereas the major pollution source was from key polluting enterprises. The emissions in the R&D park were significantly lower than those in manufacturing parks, with atmospheric pollutant emissions accounting for 25% of the manufacturing park's emissions. ② Energy structure and intensity, along with pollutant emission reduction measures, contributed 62.6% and 37.4% to pollution and carbon emission reduction for the R&D park and 81.6% and 13.5% for manufacturing park, respectively. ③ Adjusting the energy structure of the park and prioritizing the management of key polluting enterprises could achieve synergistic emission reduction, with the rate of emission reduction primarily reflecting atmospheric pollutants. Reducing energy intensity could also facilitate synergistic emission reduction, with a rapid rate of carbon emission reduction. Optimizing the industrial structure could lead to different degrees of pollution and carbon emissions increasing synergistically or not synergistically, owing to the particularity of the industrial structure of the park. ④ Applying measures to adjust the energy structure and reduce energy intensity and pollutant emissions into the collaborative path should be a priority. The governance scope of key polluting enterprises should be appropriately expanded in manufacturing parks. The synergistic effect of public environmental protection facilities of R&D parks should be focused on, in addition to reducing corporate pollutant emissions. Measures to optimize industrial structure at the park level should be adjusted to local conditions and scientifically guide industrial transformation and the settlement of high-tech enterprises.

Critical review on effective utilization of 5R technique in life cycle management of lithium ion battery

Lithium-ion batteries (LIBs) are essential elements of electric vehicles and many energy storage systems. Automobile industry has leaded the way to the growth of the transportation industry. This growth has been greatly hampered due to environmental pollution, fossil fuel crisis, and growing injurious effects on individual wellbeing. The environment, and particularly air quality, is worsening as a result of uncontrolled urban growth and development Its utilization is increasing day-by-day with more number of battery-powered vehicles on road. Vehicle electrification has been studied as a possible solution to the problem of climate change for decades. Electrification of transportation is supported all over the world to reduce atmospheric air pollutant emissions, greenhouse gas emissions, and depletion of fossil fuels. Many predictions in recent years have expected widespread adoption of electric vehicles which would mostly be fuelled by lithium-ion batteries due to their high energy and power density and extended cycle life. In present work is, critical review on recycling techniques of LIBs extraction of precious material content and 5R technique has been discussed along with systematic approach for life cycle management of LIBs.

Catalytic conversion of triglycerides to biodiesel using ZnO/SnTiO4/SBA-15 nanostructures

The imperative for the present era revolves around the development of sustainable energy resources, driven by the depletion of conventional energy sources and the escalating global energy demand. Concurrently, the combustion of fossil fuels releases detrimental pollutants, including carbon oxides, sulfur compounds, nitrogen oxides, and particulate matter, contributing to atmospheric pollution. Biodiesel, as an alternative fuel, offers numerous advantages compared to fossil fuels, including renewability and reduced emission of atmospheric pollutants. In this study, we explore the application of ZnO/SnTiO4/SBA-15 nanostructure as a nanocatalyst for the biodiesel formation, aiming to enhance reaction efficiency and product quality. The investigation begins with the preparation and analyzation of ZnO/SnTiO4/SBA-15 nanostructure, which demonstrate a high surface area (534 m2/g), mesoporous surface (pore size 3.54 cm3g-1) and unique catalytic properties. The results designated that 99 % biofuel formation was attained in 5 h, and 65 °C temperature. The results show that ZnO/SnTiO4/SBA-15 exhibit remarkable catalytic activity, effectively promoting the transformation of triglycerides into biodiesel with reduced reaction times and minimal byproducts. Furthermore, this research evaluates the influence of reaction parameters, i.e. temperature, methanol and oil ratio, and catalyst loading, on the biofuel formation and quality. Optimization studies reveal that 65 °C temperature, 30 mg catalyst and 5 h reaction times are the suitable conditions for the production of high yield biodiesel while minimizing resource consumption. The findings of this study highlight the significance of ZnO/SnTiO4/SBA-15 nanostructure as a catalyst in the transesterification process, emphasizing their potential to revolutionize biodiesel production by offering a more efficient, environmentally responsible, and economically viable approach.

High-resolution atmospheric emissions estimate from dredging activities during port expansion in Veracruz, Mexico

Maritime traffic has increased worldwide, generating the need to modernize and expand ports. The Port of Veracruz, a central hub on the Gulf of Mexico, is expanding to meet maritime demand. While the project has benefits, it can also have negative aspects, such as air pollution. One activity that can significantly impact air emissions during port expansion is dredging. Therefore, the objective of this study was to quantify the atmospheric emissions of criteria pollutants, toxics, and greenhouse gases generated by the dredging activity. For this purpose, emissions estimates resulting from the in-situ dredged volume was integrated considering two types of dredges, the U.S. Environmental Protection Agency methodology with a bottom-up approach and the National Oceanic and Atmospheric Administration's Automatic Identification System data with a 1 min resolution. The top emissions for criteria pollutants were 70 ± 4.7 Mg/yr of carbon monoxide, for toxics 13 ± 1 Mg/yr of volatile organic compounds, and for greenhouse gases 41,000 ± 4,034 Mg/yr of carbon dioxide, primarily in hotelling. These findings provide vital information for environmental management during port modernization, maintenance, and expansion.

Synthesis of Ceiba pentandra biodiesel using ultrasound and infrared radiation: Comparison and fuel characterisation.

Abstract The continuous expending of the economy and population in modern society has caused an increase in energy usage. Currently, fossil fuels and renewable energy are used to generate energy, contributing to greenhouse gas emissions. A significant effort has been made globally to address the issue of rising emissions by boosting the usage of renewable energy. In comparison to fossil fuels, biodiesel has many benefits, including the ability to be produced from a wide range of feedstocks, the ability to be renewable, and the reduction of atmospheric pollution emissions. Besides, advanced technologies can help the biodiesel sector meet the energy demand while producing high-quality biodiesel. The Ceiba pentandra was used for biodiesel production using ultrasound-infrared applications in the present research work. The study aims to produce biodiesel for a better conversion rate and improve fuel properties. Comparisons were conducted using a combination of infrared ultrasound versus ultrasound irradiation. The results show that ultrasound produced the highest yield of 98.76% when the conditions were as follows: methanol/oil ratio: 60%, KOH: 1%, reaction time: 50 minutes. Yet, the addition of infrared on ultrasound has also produced a high conversion yield in a shorter time than ultrasound. A 98.42% biodiesel yield option when using infrared-ultrasound irradiation with conditions as follows: methanol/oil ratio: 60%, KOH: 1%, reaction time: 30 minutes. As both applications were examined, the ultrasound-infrared application was preferable in saving time and energy constraints for biodiesel production. The fuel properties were found to be equivalent to ASTM D6751 and EN 14214 biodiesel standards.

A novel potential cause of extreme precipitation in the northwest China

The northwest China is a climate change-sensitive and ecologically vulnerable area. Under the backdrop of global warming, this region exhibits clear characteristics of warming and wetting. In recent years, the causes of climate change in the northwest China has become a widely-focused topic. Previous research has mainly attributed the increase in precipitation to changes in the westerly belt and enhanced local convective activity caused by global warming. South Asia, beside the Tibetan Plateau from the northwest China, is one of the regions with the fastest growth in global atmospheric pollutant emissions. This study utilizes reanalysis data such as ERA5 and MERRA-2. Statistical methods, including Theil-Sen Median trend analysis and Singular Value Decomposition analysis, are employed to analyze the spatiotemporal characteristics of South Asian aerosols, extreme precipitation in the northwest China, and the correlation between the two. The study reveals the existence of two key aerosol-precipitation response areas. Synthetic analysis of the meteorological elements of the response events in both regions is conducted to explore the possible physical mechanisms behind the correlation between South Asian aerosols and precipitation in the northwest China. The result of this study is to provide a new perspective on the causes of extreme precipitation in the arid region of northwest China.

Emerging technologies in the fight against climate change

Climate change is directly related to global warming. Such warming is caused by high greenhouse gases emissions into the atmosphere due to anthropogenic activities. Because of this, there is a greater incidence of health problems in the population, not to mention the damage to the environment. There has been increasing debate and discussion about ways to reduce greenhouse gas emissions as a way of mitigating climate change. Given this, information and communication technologies are an important factor that can bring benefits and gains to the reduction and/or monitoring of these gases. Therefore, the current work aimed to identify information and communication technologies (ICTs) for monitoring industrial atmospheric emissions that contribute to the increase in climate change. Regarding the research methodology, it is a applied research, has a qualitative approach and in terms of its objective, it is characterized as exploratory. Regarding the results, it was proven through practical examples in companies that it is possible to use ICTs to minimize and/or mitigate the emission of atmospheric pollutants. Therefore, it is concluded that technologies can combat the causes of climate change within companies and even smart cities.

Effect of changes in the fuel type of thermal power plants on the spatial distribution and levels of PAH pollution in the Vorkuta agglomeration beyond the Arctic Circle

The paper is a study of the composition of 15 polycyclic aromatic hydrocarbons (PAHs) in the snow cover of Vorkuta (Komi Republic) in the impact zone of the fuel and energy complex in 2017 and 2023. We have identified high aerotechnogenic pollution of the Vorkuta city and adjacent territories with PAHs during heating with fuel oil and coal, with a mean concentration of 301.6 ng/L (meltwater plus particles) and spatial distribution of 85.2 μg/m2. There is a significant decrease in PAH levels when the fuel for thermal power plants has been changed to natural gas, with a mean concentration of 26.1 ng/L (meltwater plus particulates) and spatial distribution of 4.9 μg/m2. The deposition areas of different PAH fractions are identified in the impact zones of Thermal Power Plants 1 and 2, the Central Boiler House and the urbanised areas of the Vorkuta agglomeration. 2-4-ring PAHs dominate in the emissions, accounting for 92–100 % of the sum of PAHs from coal/oil combustion and 66–93 % from natural gas combustion. The indicator ratios of PAHs in the snow cover of Vorkuta in both 2017 and 2023 indicate their predominantly pyrogenic genesis. The environmental risk coefficients of PAHs in the snow cover and their change from 2017 to 2023 are calculated. TEQ changed from 2.1 ng/L (mean) in the 2017 season to 1.7 ng/L (mean) in the 2023 season. The risk quotients have been reduced from moderate risk to low risk. Reconstruction of thermal power plants when replaced by more environmentally friendly fuel (natural gas) reduces the amount of atmospheric emissions of organic pollutants.

A Review on Economic Dispatch of Power System Considering Atmospheric Pollutant Emissions

The environmental/economic dispatch (EED) of power systems addresses the environmental pollution problems caused by power generation at the operational level, offering macroscopic control without requiring additional construction and remediation costs, garnering widespread attention in recent years. This paper undertakes a comprehensive review of existing EED models, categorizing them according to the control of atmospheric pollutants into total air pollutant control (TAPC) and control considering the spatial and temporal diffusion (STD) of atmospheric pollutants. In addition, various methods employed to address the EED problems, as well as the current state of research on multi-area EED models, are presented. Finally, this paper analyzes and summarizes the literature on existing EED models, highlighting the deficiencies of the current work and future research directions. Through these explorations, the authors find that controlling the EED model by considering TAPC is more suitable for general macro planning, whereas the EED model considering the STD of air pollutant emissions enables more precise and effective control. Summarizing such models and techniques is conducive to developing dispatch plans adapted to local conditions, which is significantly beneficial for public welfare and government management, promoting sustainable and environmentally friendly power system dispatch methods.

Scenario analysis of energy consumption and related emissions in the transportation industry-a case study of Shaanxi Province.

In the context of pursuing carbon neutrality and balancing the use of fossil fuels with renewable energy, the transportation industry faces the challenge of accurately predicting energy demand, related emissions, and assessing the effectiveness of energy technologies and policies. This is crucial for formulating energy management plans and reducing carbon dioxide (CO2) and atmospheric pollutant emissions. Currently, research on energy consumption and emission forecasting primarily relies on energy consumption quantities and emission factors, which lack precision. This study employs the low emissions analysis platform (LEAP) model, utilizing a "bottom-up" modeling approach combined with scenario analysis to predict and analyze the energy demand and related emissions in the transportation industry. Compared to previous studies, the methodological framework proposed in this research offers higher precision and can explore energy-saving and emission-reduction pathways for different modes of transport, providing a valuable energy forecasting tool for transport policy formulation in other regions. The forecast results indicate that under the business-as-usual (BAU) scenario, by 2049, the energy consumption and related emissions in Shaanxi Province's transportation industry are expected to increase by 1.15 to 1.85 times compared to the baseline year. In the comprehensive (CP) scenario, the industry is projected to reach a carbon peak around 2033. The study also finds that energy consumption and emissions predominantly originate from private passenger vehicles, highway freight, and civil aviation passenger, which have the greatest potential for emission reduction under the transport structure optimized (TSO) scenario. Therefore, policymakers should consider regional development characteristics, combine different transportation modes, and specifically analyze the emission reduction potential of the transportation industry in various regions, formulating corresponding reduction policies accordingly.

Temporal-spatial characteristics and sources of heavy metals in bulk deposition across China

With the rapid development of industries, agriculture, and urbanization (including transportation and population growth), there has been a significant alteration in the emission and atmospheric deposition of heavy metal pollutants. This has consequently given rise to a range of ecological and environmental health issues. In this study, we conducted a comprehensive two-year investigation on the temporal and spatial distribution characteristics of heavy metals in atmospheric deposition across China based on the Nationwide Nitrogen Deposition Monitoring Network (NNDMN). The atmospheric bulk deposition of Lead (Pb), Arsenic (As), Nickel (Ni), Selenium (Se), Chromium (Cr) and Cadmium (Cd) were 6.32 ± 1.59, 4.49 ± 0.57, 1.31 ± 0.21, 1.05 ± 0.16, 0.60 ± 0.06 and 0.21 ± 0.03 mg m−2 yr−1, respectively, with a large variation among the different regions of China. The order for atmospheric deposition flux was Southwest China > Southeast China > North China > Northeast China > Qinghai-Tibet Plateau and rural area > urban area > background area. The concentrations of heavy metals in bulk deposition exhibit seasonal variation with higher levels observed during winter compared to summer and spring, which are closely associated with anthropogenic activities. The Positive Matrix Factorization (PMF) results indicated that combustion, industrial emissions and traffic are the primary contributors to atmospheric deposition of heavy metals. The single factor pollution index (Pi) of heavy metals is consistently below 1, and the composite pollution index (Ni) is 0.16 across China, indicating that atmospheric heavy metal deposition is at a pollution-free level. The comprehensive potential ecological risk index of heavy metals is 11.8, with Cd exhibiting the highest single factor potential ecological risk index at 7.09, suggesting that more attention should be paid to Cd deposition in China. The present study reveals the spatial-temporal distribution pattern of atmospheric heavy metals deposition in China, identifying regional source characteristics and providing a theoretical foundation and strategies for reducing emissions of atmospheric pollutants.

Dynamic evaluation of China's atmospheric environmental pressure from 2008 to 2017: Trends and drivers

Evaluating the pressure of atmospheric pollutant emissions on the atmospheric environment is crucial for effective pollution control and emission reduction policies. This study introduces a novel Atmospheric Environmental Pressure Index (AEPI) and employs a dynamic comprehensive method to evaluate China's Atmospheric Environmental Pressure (AEP) across 31 provinces from 2008 to 2017. The drivers of AEP were analyzed using a spatial panel data model, uncovering the integral role of pollution reduction policies, particularly the Air Pollution Prevention and Control Action Plan, which led to a 25% reduction in AEP during its enforcement. Our findings reveal significant spatial disparities in AEP, with higher levels in the Beijing-Tianjin-Hebei and Yangtze River Delta regions. The regression analysis identifies economic development, industrial structure, energy efficiency, environmental regulations, and urbanization as key influencing factors, though their impacts vary across different regions, suggesting the need for region-specific pollution control policies. Furthermore, the shift in the AEP gravity center from 2008 to 2017 indicated a southeastward movement, suggesting the necessity to focus air pollution control efforts on the southeast provinces. In conclusion, the AEPI developed in this study enables comparative analysis of AEP across different regions and facilitates the monitoring of long-term trends, which is valuable in guiding regional air pollution control in China.

Divergent features of the upper-tropospheric carbonaceous aerosol layer: Effects of atmospheric dynamics and pollution emissions in Asia, South America, and Africa

Abstract The upper-tropospheric carbonaceous aerosol layer (TCAL) represents the increase of aerosols in the upper-troposphere. It was first discovered over Asia but was found in this study to also occur over South America and Africa. The TCALs over three regions typically exist during the strong deep convection season, with the Asian, South American, and African TCALs showing peak intensity during July–August, October–December, and November–December, respectively. Over Asia, the TCAL has the highest altitude and widest spread due to strongest deep convection and upper-troposphere anticyclonic system. TCAL intensity is highest in South America maybe due to heaviest pollutant emissions. Anthropogenic pollution from India and western China produces two Asian TCAL centers, whereas widespread wildfires result in single centers over South America and Africa. TCAL radiative effect at the top of the atmosphere has warming effects over Asia (+0.23 W m−2), whereas cooling effects perform over South America (−0.54 W m−2) and Africa (−0.20 W m−2) owing to its altitude and the divergent strengths of black-carbon absorption and organic-carbon scattering.

Unveiling the Spatial-Temporal Characteristics and Driving Factors of Greenhouse Gases and Atmospheric Pollutants Emissions of Energy Consumption in Shandong Province, China

As the largest energy-consuming province in China, Shandong faces the dual task of greenhouse gas (GHG) reduction and atmospheric pollution control. Based on the latest activity data and updated emission factors, this study establishes a high-resolution emission inventory (5 km × 5 km) for GHGs and main atmospheric pollutants from the energy consumption sectors of Shandong Province from 2010 to 2021, quantifies the relationship between social economic factors and GHGs and atmospheric pollutants emissions using the expanded stochastic environmental impact assessment (STIRPAT) model, and forecasts the future emission trend with the help of the scenario analysis method. Results indicate that the electricity and transportation sectors are the main contributors to all pollutants. Spatially, the high value of pollutants is mainly concentrated in the urban agglomerations of central and eastern Shandong. Up to 72% of GHGs and 50% of air pollution emissions are attributed to the top 10% of emission grids. Emission peaks occur mainly in summer and winter due to straw burning, increased utilization of temperature-controlled facilities, and expansion of plant capacity. Population, energy consumption, the proportion of secondary industry, and energy consumption intensity are the most significant influencing factors for pollutant emissions. Scenario analysis results indicate Shandong province can reach its carbon peak in 2027 without sacrificing population growth or economic progress.

Concentrated fireworks display-induced changes in aerosol vertical characteristics and atmospheric pollutant emissions

Fireworks affect the atmospheric environment and human health due to the rapid release of high levels of air pollutants. It is crucial to clarify the vertical characteristics of air pollutants and quantify the emission quantity for accurate control and health assessment. With the use of an unmanned aerial vehicle and a ground-based LiDAR system, we investigated the vertical profiles of particulate matter (PM) under the policy of concentrated fireworks detonation in a megacity (i.e., Changchun) in Northeast China and developed emission factors for fireworks displays. The results showed that the PM2.5, PM10, SO2 concentrations within a height of 200 m in the core area of fireworks display significantly increased by 143.8 %, 63.7 % and 174.3 %, respectively, on the day of the Lantern Festival relative to the background concentrations. There was a decreasing trend in the PM2.5 concentration with increasing height, with a maximum vertical decrease of 64 μg/m3 per 100 m. Despite a general decline in the concentration, the vertical distribution of polluted air masses exhibited heterogeneity, occasionally exhibiting a bimodal distribution pattern. Moreover, the correlation coefficients between the aerosol optical depth (AOD) at different altitudes (0.2–0.4, 0.4–0.7, and 0.7–1.0 km) and the ground-level PM concentration were 0.29, −0.35, and −0.35, respectively. This phenomenon indicates a reduced influence of ground-level PM emission on the AOD at altitudes from 0.4 to 1.0 km and the increased potential for aerosol particles to escape upwards, particularly in the troposphere. Furthermore, an approach combining real-time stereoscopic monitoring of PM and downwind wind speed was developed to calculate the estimated firework emission factors. The emission factors recorded during the Lantern Festival, specifically between 20:00 and 24:00, were 128.6 ± 28.3 mg/m2 per 10 min and 92.7 ± 23.2 mg/m2 per 10 min for PM2.5 and PM10, respectively, including an uncertainty of 9 %–14 % generated by the sensors. The proposed approach and corresponding emission factors could be used to easily quantify air pollutant emissions originating from fireworks displays and to conduct further numerical simulations for air pollution regulation and health assessment.

Scenario simulation and synergistic effect analysis of CO2 and atmospheric pollutant emission reduction in urban transport sector: A case study of Chengdu, China

Realizing coordinated control of CO2 and atmospheric pollutants in comprehensive transportation in large cities is an important way to promote sustainable urban development. Based on the LEAP framework, this study established a transport CO2 and atmospheric pollutant emission analysis model for Chengdu from 2021 to 2040, set up three main scenarios for the study of carbon peaking trend and 12 sub-scenarios for the study of the synergistic effect of various emission reduction measures. In addition, the synergistic effects were analyzed by radar charts, grading charts of synergistic effects and the synergetic equivalence index. The results show that under the Green Scenario (GS) and the Strengthen Green Scenario (SGS), the CO2 emissions from comprehensive transportation in Chengdu will peak at 26.774 × 106 t and 23.507 × 106 t in 2032 and 2029, respectively. The emissions of other atmospheric pollutants show a general downward trend. Under SGS, The measures that play the greatest role in reducing CO2, CO, VOCs, and NOx emissions by 2040 are NEV (New energy conversion of vehicles), Among them, the CO2 emission reduction rate relative to BS scenario is 20.7%. While the measures that play the greatest role in reducing PM and SO2 emissions are IES (Improvement of emission standards) and SRT (Strengthen railway transportation), respectively. Compared with other measures, the synergistic effect of SRT is the most highest. The emission reduction effect of NEV is most significant, with a synergistic effect level above level II. Under the joint regulation of multiple measures by GS and SGS, the synergistic equivalence index based on air quality standards has been effectively controlled, showing a downward trend. Overall, Chengdu faces challenges due to a large number of motor vehicles and air passenger throughput. Therefore, vigorously developing hydrogen vehicles and electric vehicles, strengthening railway construction in Chengdu, transferring the pressure of civil aviation and road transportation to railway, can make significant contributions to the pollution reduction and carbon reduction of Chengdu's transportation sector.

Coordination Relationship of Carbon Emissions and Air Pollutants under Governance Measures in a Typical Industrial City in China

Coordinating and controlling carbon and atmospheric pollutant emissions in industrial cities poses challenges, making it difficult to formulate effective environmental governance strategies in China. This study used the Community Multiscale Air Quality (CMAQ) and Long-range Energy Alternatives Planning (LEAP) models, with a typical industrial city in the Sichuan Basin as the case study. Five emission reduction scenarios, one integration scenario, and one baseline scenario were set to quantitatively analyze the synergistic effect between carbon emissions and atmospheric pollutant emissions. The results indicate a high synergy between sulfur dioxide and greenhouse gases. For every one-point decrease in the Air Quality Composite Index (AQCI), the Industrial Restructuring Scenario (IR), Other Source Management Scenario (OSM), Transportation Energy Efficiency Improvement Scenario (TEEI), Industrial Energy Efficiency Improvement Scenario (IEEI), and Transportation Restructuring (TR) scenarios would require a reduction in carbon emissions by 56,492.79 kilotons, 39,850.45 kilotons, 34,027.5 kilotons, 22,356.58 kilotons, and 3243.33 kilotons, respectively. The results indicate that governance measures, such as improving transportation structure and upgrading industrial technologies, provide stronger support for simultaneous carbon emissions reductions and air quality improvement.

Energy, economic, and environmental evaluation of a GAX-based cross-type absorption-resorption heat pump

Thermally driven absorption heat pump is regarded as one of the most promising methods to efficiently utilize low-grade heat, reduce energy consumption and greenhouse gas emissions. However, there are still limitations when using it at low ambient temperature in cold regions, and its application is limited by their low system performance. In this study, we proposed a novel Generator-absorber heat exchange (GAX) based NH3/H2O cross-type absorption-resorption heat pump driven by waste flue gas, which amalgamates the absorption-resorption and GAX cycles, yielding a dual advantage of diminished heat source temperature and operating pressure requirements. Additionally, it substantively enhances the system's performance by capitalizing on the cross-type solution cycle integration. A mathematical model has been developed and the results have been compared and validated with those reported in the literature. The proposed system is comprehensively studied from the view of energy, exergy, economic and environmental (4E) analysis to determine its advantages and disadvantages. The results reveal that the proposed system achieves a maximum COP of 2.742 under specific operating conditions, which is 82.8% higher than the conventional absorption heat pump (AHP), and 30.57% higher than the conventional GAX-AHP. Besides, the addition of a compressor can significantly enhance the performance of the system at lower driving heat source temperatures. At a PH/PL pair of 1.7/0.47 MPa, the static payback period is 4.113 years, with the heating capacity of 88.51 kW and the supply water temperature of 54.6 °C, showcasing favorable system performance. Furthermore, the total atmospheric pollutant emissions could be reduced by 30,998 kg/year compared to the conventional heating method.