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Volatile Organic Compounds (VOCs) are not only essential precursors for the formation of ozone and PM2.5, but also hazardous to human health and responsible for unpleasant odors. The pharmaceutical industry has become an important industrial source of VOCs due to China's large emissions and complex emission chains. In total, 245 VOCs samples were collected and analyzed from 11 typical pharmaceutical companies in Zibo City of the North China Plain, in order to investigate the VOCs emission characteristics and odor impacts. The emission factor for the pharmaceutical industry was 7.97 ± 8.21 g/kg pharmaceuticals, while the main emission links were chimney emissions, equipment sealing leakage, and so on. Finally, considering both purifying efficiency and economic benefits, the multistage absorption (AB) method is most effective for VOCs concentrations below 100 mg/m3, while UV photo-oxygenation combined with adsorption (UVA) is more suitable for concentrations below 300 mg/m3. The Regenerative Thermal Oxidizer (RTO), Catalytic Oxidizer (CO), and Condensation + Adsorption (CA) technologies demonstrated greater stability and efficiency, particularly in the treatment of complex organic pollutants, highlighting their advantages in both VOCs and odor removal at higher concentrations. [ABSTRACT FROM AUTHOR]

Traffic emissions are a major source of ambient air pollution, and exposure to these emissions has been linked to numerous adverse health effects. Our study investigated the reduction of traffic emissions in downtown Tianjin, China, and assessed its health benefits. Based on the vehicle emission inventory, The Atmospheric Dispersion Modelling System (ADMS) was adopted for simulating the dispersion of traffic-related air pollutants including primary fine particulate matter (PM2.5), and carbon monoxide (CO). The Benefits Mapping and Analysis Program (BenMAP) was then used to quantify the benefits of emission reductions with respect to cardiovascular disease and respiratory disease. We found a downward trend in PM2.5 and CO concentrations from 2015 to 2019 (PM2.5: 17.8 to 10.5μg/m3, CO: 2.3 to 1.3mg/m3). Furthermore, in line with the reduction of average annual PM2.5 and CO attributable to traffic emissions during 2016–2019 compared with 2015, the accumulative deaths from the two diseases mentioned above in these years decreased by 156 and 961 respectively. Our study constructs an integrated framework combining emission inventories, air quality modeling, and population health benefits, which can be used for further health effects of related air quality improvement. [ABSTRACT FROM AUTHOR]

In this study, dynamometer engine tests were conducted to investigate the impact of test cycle and fuel type on fuel consumption and exhaust emissions of a heavy-duty diesel engine. This study presented novel approaches by utilizing comprehensive statistical analysis to assess these impacts on particulate matter (PM), PM-bound polycyclic aromatic hydrocarbons (PAHs), and multiple gaseous pollutants. Four types of fuels—two conventional diesels (X and Y) and each with 5% blend of biodiesel—were used under European Transient Cycle (ETC) and European Stationary Cycle (ESC). There were statistically significant higher fuel consumption and emission rates (by 9–73%) under ETC than ESC due to more occurrences of lower engine speeds and loads under ESC, and X fuels had higher emission rates of PM and carbon dioxides ([CO 2 ]; 2.1–13%) but lower rates of hydrocarbons ([THC]; 44%) attributed to higher cetane number, sulfur contents and boiling points. Compared with conventional diesel, biodiesel blend had slightly lower emission rates of PM, CO, and NO X (1.7–6.6%) but higher fuel consumption (1%) and CO 2 and THC emission rates (0.9–2.1%). The results of this study contributed to the limited datasets on the interactive effects of test cycle with fuel property on diesel vehicle exhaust emissions. • Impacts of test cycle and fuel type on diesel engine emissions were investigated. • Test cycle, fuel, and their interaction explained >84% of variance in emissions. • PM, CO, and NOx emissions were slightly lower in biodiesel blend than fossil diesel. • Fuel consumption, PM and gas emissions were significantly higher under ETC than ESC. • Higher PAHs in fuels produced more heavy molecular weight PM-bound PAH emission. [ABSTRACT FROM AUTHOR]

Diesel-powered agricultural machinery (AM) is a significant contributor to air pollutant emissions, including nitrogen oxides (NOx) and particulate matter (PM). However, the fuel consumption and pollutant emissions from AM remain poorly quantified in many countries due to a lack of accurate activity data and emissions factors. In this study, the fuel consumption and air pollutant emission from AM were estimated using a survey and emission factors from the literature. A case study was conducted using data collected in Anhui, one of the agricultural provinces of China. The annual active hours of AM in Anhui ranged 130 to 175 h. The estimated diesel fuel consumption by AM was 1.45 Tg in 2013, approximately 25% of the total diesel consumption in the province. The air pollutants emitted by AM were 57 Gg of carbon monoxide, 14 Gg of hydrocarbon, 74 Gg of NOx and 5.7 Gg of PM in 2013. The NOx and PM emissions from AM were equivalent to 17% and 22% of total on-road traffic emissions in Anhui. Among nine types of AM considered, rural vehicles are the largest contributors to fuel consumption (31%) and air emissions (33–45%). [ABSTRACT FROM AUTHOR]