Air pollutant emissions from the asphalt industry in Beijing, China

Improving our understanding of air pollutant emissions from the asphalt industry is critical for the development and implementation of pollution control policies. In this study, the spatial distribution of potential maximum emissions of volatile organic compounds (VOCs) in the complete life cycle of asphalt mixtures, as well as the particulate matter (PM), asphalt fume, nonmethane hydrocarbons (NMHCs), VOCs, and benzoapyrene (BaP) emissions from typical processes (e.g., asphalt and concrete mixing stations, asphalt heating boilers, and asphalt storage tanks) in asphalt mixing plants, were determined in Beijing in 2017. The results indicated that the potential maximum emissions of VOCs in the complete life cycle of asphalt mixtures were 18,001 ton, with a large contribution from the districts of Daxing, Changping, and Tongzhou. The total emissions of PM, asphalt fume, NMHC, VOCs, and BaP from asphalt mixing plants were 3.1, 12.6, 3.1, 23.5, and 1.9 × 10^?3 ton, respectively. The emissions of PM from asphalt and concrete mixing stations contributed the most to the total emissions. The asphalt storage tank was the dominant emission source of VOCs, accounting for 96.1% of the total VOCs emissions in asphalt mixing plants, followed by asphalt heating boilers. The districts of Daxing, Changping, and Shunyi were the dominant regions for the emissions of PM, asphalt fume, NMHC, and BaP, while the districts of Shunyi, Tongzhou, and Changping contributed the most emissions of VOCs.     

环境矿物材料在水体污染治理进展中的研究

环境矿物材料在水体污染治理中的应用受到了人们的广泛关注.本文综述了环境矿物材料的改性方法,主要介绍了物理改性,主要有水热改性和焙烧改性,化学改性主要有无机改性和有机改性,探讨了在水体污染治理中的应用研究现状,主要包括去除重金属离子、去除有机污染物、去除无机阴离子和去除其他污染物,给出了环境矿物材料的发展趋势,主要包括加强环境矿物材料的研究、加强改性方法的研究和拓展与其他方法的联用等方面的应用研究.     

水体中苦味酸的测定方法研究进展

介绍了目前国内外水体中苦味酸测定方法的研究与发展状况,阐述了每个分析方法的原理、测定条件、线性范围、检测限、干扰因素及消除方法、精密度和应用情况。为广大环保工作者的实际工作提供参考和借鉴。     

Genotoxicity of drinking water treated with different disinfectants and effects of disinfection conditions detected by umu-test

The genotoxicity of drinking water treated with 6 disinfection methods and the effects of disinfection conditions were investigated using the umu-test. The pretreatment procedure of samples for the umu-test was optimized for drinking water analysis. The results of the umu-test were in good correlation with those of the Ames-test. The genotoxicity and production of haloacetic acids (HAAs) were the highest for chlorinated samples. UV + chloramination is the safest disinfection method from the aspects of genotoxicity, HAA production and inactivation effects. For chloramination, the effects of the mass ratio of Cl₂ to N of chloramine on genotoxicity were also studied. The changes of genotoxicity were different from those of HAA production, which implied that HAA production cannot represent the genotoxic potential of water. The genotoxicity per chlorine decay of chlorination and chloramination had similar trends, indicating that the reaction of organic matters and chlorine made a great contribution to the genotoxicity. The results of this study are of engineering significance for optimizing the operation of waterworks.     

Efficient degradation of chlorobenzene in a non-thermal plasma catalytic reactor supported on CeO2/HZSM-5 catalysts

Chlorobenzene removal was investigated in a non-thermal plasma reactor using CeO₂/HZSM-5 catalysts. The performance of catalysts was evaluated in terms of removal and energy efficiency. The decomposition products of chlorobenzene were analyzed. The results show that CeO₂/HZSM-5 exhibited a good catalytic activity, which resulted in enhancements of chlorobenzene removal, energy efficiency, and the formation of lower amounts of by-products. With regards to CO₂ selectivity, the presence of catalysts favors the oxidation of by-products, leading to a higher CO₂ selectivity. With respect to ozone, which is considered as an unavoidable by-product in air plasma reactors, a noticeable decrease in its concentration was observed in the presence of catalysts. Furthermore, the stability of the catalyst was investigated by analyzing the evolution of conversion in time. The experiment results indicated that CeO₂/HZSM-5 catalysts have excellent stability: chlorobenzene conversion only decreased from 78% to 60% after 75 hr, which means that the CeO₂/HZSM-5 suffered a slight deactivation. Some organic compounds and chlorinated intermediates were adsorbed or deposited on the catalysts surface as shown by the results of Fourier Transform Infrared (FT-IR) spectroscopy, scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) analyses of the catalyst before and after the reaction, revealing the cause of catalyst deactivation.     

Optimization of regional economic and environmental systems under fuzzy and random uncertainties

Environmental problems associated with socio-economic development have been growing concerns faced by many regional and/or national authorities. However, effective planning may encounter difficulties since uncertainties existing in a number of impact factors and pollution-related processes are often not well acknowledged and reflected. This study advances an interval-fuzzy chance-constrained programming (IFCP) method for planning regional economic and environmental systems, where uncertainties presented as intervals, fuzzy sets and probability distributions can be tackled. The developed method is applied to a real-world case for economic and environmental planning in the New Binhai District in the Municipality of Tianjin, China. Two scenarios based on multiple environmental constraints are examined. The results can help identify desired alternatives for planning regional development strategies, where compromised schemes are provided under an integrated consideration of economic efficiency and environmental protection under multiple uncertainties.     

Size distribution and composition of phosphorus in the East Tiao River, China: the significant role of colloids

The environmental risk of aquatic phosphorus (P) critically depends on its mobility and bioavailability, both of which are greatly affected by the size distribution and composition of P. The size distribution (particulate, colloidal and truly dissolved phase) of P, composed of molybdate reactive P (MRP) and molybdate unreactive P (MUP), was determined at twenty-three typical sections of the East Tiao River, China in the plum rain season. Results indicated particulate P was dominant followed by the truly dissolved P, while colloidal P was quantitatively the lowest in the whole river. From upstream to downstream, particulate P sharply increased, along with a slight decrease of truly dissolved P. However, colloidal P remained at a relatively stable level in the whole river, ranging from below detection limit to 0.025 mg L(-1), 0 to 13.4% of total P (TP). Furthermore, colloidal MRP exhibited a rising trend downriver as compared to upriver, with the notable transfer of MRP from the truly dissolved phase to particulate and colloidal phases. Particle concentration effect for colloids, observed in the study of MRP distribution, further corroborated the role of colloids in MRP solid/liquid partitioning. These observations, in this large-scale field investigation, fitted the "colloidal pumping" hypothesis. It may be concluded that colloids act as the intermediate and buffer in the dynamically balanced transfer of P from truly dissolved phase to large particulate phase, having a significant role in size distribution of P.     

城市和农村社区防灾减灾手册和挂图的设计与编制

介绍了城市和农村社区防灾减灾手册和挂图的设计和编制,包括设计和编制原则、编制流程、手册和挂图的内容与结构、挂图编制的主要表示方法以及编制的组织和实施过程。     

A cumulative-risk assessment method based on an artificial neural network model for the water environment

Environmental Science and Pollution Research - To analyze the cumulative risks to the water environment, the backpropagation artificial neural network (BP-ANN), a self-adapting algorithm, was...     

The relationship between maternal perfluoroalkylated substances exposure and low birth weight of offspring: a systematic review and meta-analysis

Environmental Science and Pollution Research - Some studies have shown that maternal perfluoroalkylated substances (PFAS) exposure may be associated with low birth weight (LBW) of offspring. We...