#### Table of Content

20 May 2019, Volume 9 Issue 3
 Verification of national subjective and objective air quality forecast in 2018 by TS score ZHANG Tianhang,CHI Qianyuan,RAO Xiaoqin,WANG Jikang,ZHANG Bihui,XU Ran,JIANG Qi,LUAN Tian 2019, 9 (3):  213-222.  doi: 10.12153/j.issn.1674-991X.2019.03.080 Abstract ( 390 )   HTML ( 42 )   PDF (6639KB) ( 70 )   Until now, few works have reported comparison results between subjective and objective air quality forecast. To understand the performances of national subjective and objective air quality forecast, operational results in 2018 from National Meteorological Center were verified by threat score (TS) method. The results showed that TS score, false alarm ratio and missed alarm ratio of subjective (objective) forecast for mild and above pollution all over China in 2018 were 0.23-0.34 (0.24-0.26), 0.37-0.43 (0.39-0.41) and 0.58-0.72 (0.68-0.71), respectively. This illustrated that subjective forecast was better than objective one, but the ability of objective forecast was close to subjective forecast. Performances of subjective and objective forecast were both better in regions with heavier pollution (Jing-Jin-Ji, Fenwei Plain, Central China and Yangtze River Delta) than in lower pollution ones (Northwestern China, Southwestern China, Pearl River Delta and Northeastern China), and so did it in the heavily polluted winter than in the clean summer. With the extension of forecast time, TS scores of subjective forecast showed a downward trend, but scores of objective forecast did not change too much. In winter with heavy pollution, TS scores of 48 and 72 hours' objective forecast were higher than those of subjective forecast. Additionally, in 5 haze processes in 2018, TS scores of subjective (objective) forecast for mild, moderate and severer pollution all over China were 0.39-0.57 (0.43-0.46), 0.22-0.46 (0.25-0.30) and 0.10-0.34 (0.10-0.18), respectively. The situation of TS scores of subjective forecast higher than objective forecast accounted for 3 times in 5 processes. But performance of objective forecast was more stable with extension of forecast time, which illustrated that objective forecast could provide stable reference to forecasters in pollution process, but its ability in dealing with high pollution needs to be improved.
 DOM distribution characteristics and source analysis of Baitabu River YAN Bingfei,PENG Jianfeng,DENG Qiyu,LI Dan,LIU Xueyu,LI Jie 2019, 9 (3):  225-232.  doi: 10.12153/j.issn.1674-991X.2019.02.190 Abstract ( 141 )   HTML ( 12 )   PDF (2780KB) ( 64 )   The methods of three-dimensional fluorescence spectroscopy and Pearson correlation analysis were applied to determine the pollution characteristics and origins of DOM in a typical urbanized river, Baitabu River in northeastern China. The results indicated that fluorescence peak types of the river included UV fulvic-like peak (A peak), visible fulvic-like peak (C peak), protein-like peak (B peak) and protein-like peak (T peak). The major components order of DOM was protein-like>soluble microbial byproduct-like>fulvic-like>humic-like. The relative content of spatial distribution of DOM showed middle and lower reaches>upper reaches. The source of DOM in Baitabu River showed double characteristics of land-sourced materials and microbial degradation, and the internal pollution caused by microbial degradation could not be ignored. According to Pearson correlation analysis, the DOM concentration was correlation with NH3-N and TP concentration which showed a significant positive relationship, but was significantly negative correlation with dissolved oxygen concentration.
 Microbial community structure and distribution of constructed wetlands in Liaohe Conservation Area YAO Meichen,DUAN Liang,ZHANG Hengliang,ZHANG Chengming 2019, 9 (3):  233-238.  doi: 10.12153/j.issn.1674-991X.2019.03.040 Abstract ( 74 )   HTML ( 6 )   PDF (2116KB) ( 29 )   The high-throughput sequencing was used to study the microbial community structure and distribution of sediment and reed rhizosphere in different types of constructed wetlands (tributary inlet wetland, pond wetland and oxbow lake wetland) in Panjin of Liaohe Conservation Area. The results showed that the microbial diversity, abundance and optical transform units (OTUs) of the three kinds of wetlands sediment were higher than that of reed rhizosphere. The diversity was affected by season, and the diversity of samples in autumn was higher than that in spring. The structure and distribution of microbial communities were roughly similar. Proteobacteria was the dominant species with the highest relative abundance. Gram-negative bacteria, mainly proteobacteria, played an important role in the purification of constructed wetlands. The class and relative abundance of Proteobacteria in different types of constructed wetlands were different. The Alphaproteobacteria, Deltaproteobacteria and Gammaproteobacteria were dominated in the tributary inlet wetland, while the Gammaproteobacteria, and Alphaproteobacteria were dominated in the pond wetland. In the oxbow lake wetland, the microorganism distribution of different classes in wetland was uniform.
 Research progress of long-term nitrogen removal in subsurface flow constructed wetlands YAN Bingfei,XIAO Shuhu,LIAO Chungang,DENG Qiyu,LI Dan,LIU Xueyu 2019, 9 (3):  239-244.  doi: 10.12153/j.issn.1674-991X.2019.02.010 Abstract ( 171 )   HTML ( 19 )   PDF (768KB) ( 100 )   Subsurface flow constructed wetlands have the advantages of simple operation, low cost of construction and operation, and good environmental benefits. However, in the long-term operation, the phenomenon of low denitrification efficiency is also common. The mechanism of denitrification in subsurface flow constructed wetland was stated and the main reasons for the decrease of denitrification efficiency in long-term operation were reoxygenation capacity reduction and substrate clogging. Based on extensive literature review, the methods of improving denitrification efficiency by long-term operation of subsurface flow constructed wetlands were summarized. The measures and effects for improving denitrification efficiency were discussed from the aspects of improving reoxygenation capacity of wetland, selecting suitable filler size and gradation, and optimizing subsurface flow wetland process.
 Study on performance and membrane fouling of MBBR-MBR combined process for treatment of domestic wastewater ZHANG Hengliang,DUAN Liang,YAO Meichen,WEI Jian 2019, 9 (3):  245-251.  doi: 10.12153/j.issn.1674-991X.2019.01.240 Abstract ( 166 )   HTML ( 16 )   PDF (1650KB) ( 107 )   A moving bed biofilm reactor(MBBR)-membrane bioreactor(MBR) combined process was constructed to treat domestic wastewater, and the removal effect of pollutant and membrane fouling were investigated. The results showed that the removal rate of $NH_{4}^{+}$-N and COD could reach 97% by MBBR-MBR. The membrane suction pressure in MBR was characterized by a slow increase and then a rapid increase with the extension of the running time. Extracellular polymeric substances (EPS) and soluble microbial products (SMP) were important factors influencing membrane fouling. Ordinary chemical cleaning did not restore the MBR membrane module to the level of the new, showing irreversibility. The apparent molecular weight distribution of EPS was more extensive, while the apparent molecular weight of SMP exhibited a single peak characteristic. SMP was mainly composed of small molecular weight substances.
 Microbial community structure and succession of MBBR-MBR combined process for domestic wastewater treatment YAO Meichen,DUAN Liang,ZHANG Hengliang,WEI Jian 2019, 9 (3):  252-260.  doi: 10.12153/j.issn.1674-991X.2019.02.030 Abstract ( 113 )   HTML ( 32 )   PDF (2919KB) ( 68 )   The moving bed biofilm reactor (MBBR)-membrane bioreactor (MBR) combined process was used for the treatment of domestic wastewater. The removal effect of the reactors on the pollutants was investigated, the microbial population changes and compositional diversity in the reactors were analyzed by denaturing gradient gel electrophoresis (DGGE), and the microorganisms were classified by using cloned library. The results showed that the $NH_{4}^{+}$-N and CODCr in MBBR-MBR could acquire satisfied removal efficiency under stable operation, which were 98% and 97%. DGGE fingerprint showed that during the operation of the reactor, the microorganism community structure evolved obviously and was closely related to the temperature change, gradually forming a low temperature stable population adapted to the sewage treatment. Compared with MBR, MBBR had richer microbial population, more complex system and stronger resistance. The results of cloned library showed that the dominant species of microorganisms in MBBR and MBR were quite different, but both belonged to Proteobacteria.
 Heavy metal pollution levels and risk assessment of soils and sediments in the upstream of Miyun Reservoir, Beijing PAN Libo,WU Rihan,WANG Lei,WANG Yue,FANG Guangling,SU Benying,WANG Siyu,XIANG Bao 2019, 9 (3):  261-268.  doi: 10.12153/j.issn.1674-991X.2018.11.261 Abstract ( 116 )   HTML ( 7 )   PDF (1071KB) ( 65 )   Focusing on the Chao River and Baimaguan River located upstream of the Miyun Reservoir in Miyun District, Beijing, the concentration, potential ecological risk, and human health risk of the heavy metals, including cadmium, chromium, arsenic, lead, copper, and zinc, in the soil and sediment samples collected from the river and drainage basin were analyzed and assessed. The average concentrations of the six heavy metals were all below the Soil Environmental Quality Risk Control Standard for Soil Contamination of Agricultural Land (GB 15618-2018) for China, but exceeded the background values of Beijing. Cd was the most serious pollutant in both soil and sediment, being with 2.64 and 3.40 times of background value, while Pb, As and Cr were slightly higher than their background values. The potential ecological risk posed by Cd in soil and sediment was at moderate level, and the potential ecological risk of heavy metals in Chao River Basin was higher than that in Baimaguan River Basin. The historical iron ore mining and economic crop cultivation were identified as the primary sources of heavy metal pollution of soil and sediment in the upstream of the Miyun Reservoir. Human health risk assessment results indicated that non-carcinogenic risks and carcinogenic risks of adults and children all fell below threshold values.
 Nanofiltration membrane performance during softening process of simulated brackish groundwater in the Huang-Huai region WANG Xiaoliu,LIU Wenting,WANG Xiaoming,WANG Yibo 2019, 9 (3):  269-274.  doi: 10.12153/j.issn.1674-991X.2019.01.090 Abstract ( 125 )   HTML ( 12 )   PDF (1674KB) ( 34 )   Brackish water, which typically represented the water quality in the Huang-Huai region along the junction of the north China piedmont alluvial plain and central alluvial plain, was simulated and used as feed water to run a nanofiltration (NF) membrane system. Bench-scale experiments were carried out to evaluate NF softening separating performance. The influences of transmembrane pressure (0.6-2.1 MPa), inlet tangential flow velocity (0.09-0.38 m/s) and feedwater temperature (7-35 ℃) on the softening efficiencies of NF membrane were investigated. The results revealed that NF system produced a highest flux of 52.04 L/(m 2·h) with Ca 2+, Mg 2+, $CO_{3}^{2-}$ and $SO_{4}^{2-}$ rejection of 44.13%, 73.72%, 81.05% and 99.13%, respectively, under the optimal operating conditions of transmembrane pressure at 1.2 MPa, inlet tangential flow velocity at 0.28 m/s and feedwater temperature at 15 ℃. Under the optimal operating conditions, NF membrane achieved the highest softening performance with 53.31% of the total hardness removal efficiency. Additionally, pH values of NF permeate decreased while pH of NF retentate increased gradually with increasing of transmembrane pressure, inlet tangential flow velocity and decreasing of feedwater temperature within the testing scope.
 Application and problems of catalytic ozonation in advanced treatment of petrochemical wastewater LI Yanan,TAN Yu,WU Changyong,LIU Hengming,ZHOU Yuexi 2019, 9 (3):  275-281.  doi: 10.12153/j.issn.1674-991X.2019.02.280 Abstract ( 198 )   HTML ( 19 )   PDF (795KB) ( 75 )   Biological effluent of petrochemical wastewater treatment plant contains toxic and refractory organic compounds, which is difficult to be furtherly treated by biological process. However, with the implementation of Emission Standard of Pollutants for Petroleum Chemistry Industry (GB 31571-2015) after July 1, 2015, the petrochemical wastewater treatment plants had experienced great centralized technology improvement. Meanwhile, most of the advanced treatment units have been built by ozone/catalytic ozonation process to achieve the discharge standard. At present, most of these advanced treatment units have been in operation for more than two years. With the actual operation, a series of problems which were not taken into account at the beginning of the design have arisen. Due to low ozone utilization rate and continuous deterioration, the treatment costs continuously increased. In order to solve these problems, combined with practical conditions, four aspects of the flocs, colloidal macromolecule organic compounds, ozone mass transfer and catalysts were analyzed. In the meantime, the development trend of ozone catalytic oxidation technology in secondary effluent treatment of petrochemical industry was put forward.
 The purification effects of infiltrative dams on urban initial rainwater LUO Qijin,ZHOU Zhaoyang,LI Jingshi,HE Chenhui,YI Xingui 2019, 9 (3):  282-285.  doi: 10.12153/j.issn.1674-991X.2018.11.300 Abstract ( 122 )   HTML ( 5 )   PDF (1725KB) ( 43 )   With the development of socio-economy in China, the proportion of urban initial rainwater pollution load in urban river pollution is increasing. To solve this problem, the purification effects of infiltrative dams on urban initial rainwater were investigated through pilot-scale experiment and simulation. The results showed that the infiltrative dams systems which used zeolite, limestone, sponge iron, and volcanic rocks as reactive media, had higher removal ratios of CODCr, SS, $NH_{4}^{+}$-N, TN, and TP, which was 84.69%, 89.65%, 25.66%, 24.46%, and 50.06%, respectively. Physical interception and chemisorption of fillers and sponge iron internal electrolysis were the main mechanisms for pollutant removal in infiltrative dams system.
 Study on coupling and coordination method of land use degree and benefits: a case study of Ar Khorqin Banner WU Rihan,WU Quan,BU Ren,XIANG Bao,ZHA Na 2019, 9 (3):  286-293.  doi: 10.12153/j.issn.1674-991X.2019.03.150 Abstract ( 108 )   HTML ( 6 )   PDF (3329KB) ( 46 )   Taking the Ar Khorqin Banner as the research area and using the respective towns as the research units, the spatial difference of land use degree and benefit as well as the coupling degree and coordination degree were analyzed by using the land use degree comprehensive index, the comprehensive benefit index, and the model of coupling degree and coordination degree. The results showed that the land use degree of the whole banner was in a moderate state, and the average value of the comprehensive index of land use degree of the 14 towns was 203.2. The average value of land use comprehensive benefit index was 1.160, and the average value of land use economic benefit, ecological benefit and social benefit index was 0.451, 0.392 and 0.317, respectively. The spatial difference of land use benefit was great and the land use benefit increased gradually from the regional center to the periphery. The average value of the coupling degree between land use degree and benefit was 0.454, showing antagonism on the whole, and the average value of the coordination degree was 0.308, showing moderate coordination on the whole. The towns with high coordination degree and coupling degree between land use degree and benefit were mostly grassland and areas with animal husbandry as the supporting industry.
 Experimental study on treatment of high-oil sludge containing polymer by thermochemical cleaning and countercurrent extraction CHEN Hongshuo,LIU Jiaju,FU Zhenghui,GUO Huaicheng 2019, 9 (3):  294-301.  doi: 10.12153/j.issn.1674-991X.2019.01.120 Abstract ( 103 )   HTML ( 8 )   PDF (2080KB) ( 60 )   In order to meet the demand of resource utilization and harmless treatment of high-oil sludge containing polymer, a comprehensive treatment process with “thermochemical cleaning and countercurrent extraction” as the core was developed. The removal of crude oil from high-oil sludge containing polymer of one marine drilling platform by thermochemical cleaning and countercurrent extraction was studied experimentally. A domestic brand of washing powder was used as cleaning agent during the thermochemical cleaning. Results showed that the optimum conditions for thermochemical cleaning was temperature of 65 ℃, the liquid-to-solid mass ratio of 3:1, the cleaning time of 25 min, and the stirring rate of 450 r/min. After thermochemical treatment, the dry base oil content of oil sludge decreased from 62.0% to 25.4%, and the removal rate could reach 59.0%; moreover, the oil sludge after treatment showed good dispersion in the subsequent countercurrent extraction process. The dry base oil content of solid after “thermochemical cleaning and countercurrent extraction” was 1.7%, which perfectly met the control standards of Technical Requirements for Comprehensive Utilization and Pollution Control of Oil-bearing Sludge in Oil and Natural Gas Exploitation (SY/T 7301-2016), and the mineral oil could be delivered to the refinery for recycling.
 Research on incineration technology of returning all leachate to incinerator in MSW incineration power plant BU Yinkun 2019, 9 (3):  302-310.  doi: 10.12153/j.issn.1674-991X.2018.12.120 Abstract ( 183 )   HTML ( 6 )   PDF (1685KB) ( 52 )   Landfill leachate from MSW incineration power plant contains a variety of harmful organic compounds and heavy metals. Concentrations of CODCr and BOD5 are much higher than those of urban sewage, with high ammonia nitrogen content and strong stench, and thus thorough harmless treatment must be carried out. The current domestic landfill leachate treatment methods of most of the garbage power plants were biological treatment, physical and chemical treatment or their combined treatment methods. These methods were considered to be too complicated, expensive, and could not treat the contaminants thoroughly. The author traced back the source of landfill leachate. It was found that for a qualified waste incineration power generation boiler which was designed based on the data of combustion calculation and thermodynamic calculation by waste element analysis, the design parameters such as boiler power, efficiency, flue gas temperature could not be affected in theory, only when the leachate belonging to the waste into the furnace was fully misted and evenly sprayed into the furnace for complete incineration. Based on this point of view, the specific process of all leachate incineration was put forward in order to further improve the harmless incineration technology of refuse. The process included full misting of leachate, the number of spray entrances of atomized leachate and their corresponding positions and angles, and the way to automatically track and match the amount of leachate spray with the amount of incineration of reuse in the incineration.
 Research on environmental economic policy system of industrial air pollution control ZHANG Zhiqi,ZHANG Baoliu,LUO Hong 2019, 9 (3):  311-319.  doi: 10.12153/j.issn.1674-991X.2019.01.140 Abstract ( 85 )   HTML ( 12 )   PDF (1960KB) ( 29 )   The environmental economic policies for industrial air pollution control in the process of industrial energy utilization were analyzed by classifying and analyzing the current policies from the aspects of industrial structure adjustment, energy efficiency optimization and pollution discharge management, simulating the development scenarios of different types of cities in China, and proposing corresponding policy combination choices. For "quantity expansion" cities, VAT preferential policies and credit financing support policies were recommended to encourage the development of environmentally friendly and technologically innovative industries. For "resource-dependent" cities, it is suggested to set suitable ad valorem resource tax rate, promote tradable emission permits, supplemented by energy efficiency leader system, so as to guide industrial structure adjustment and encourage enterprises to improve energy efficiency, while conducting stricter management of pollutant emissions. For "comprehensive development-oriented" cities, it is desirable to promote the corporate environmental credit reward and punishment mechanism, give full play to the importance of the credit system in the modern economy, promote the development of environmentally friendly enterprises, and constrain and promote the enterprise to take into account both business development and environmental responsibility.
 A combination weighting method to evaluate the comprehensive environmental influence of construction project on cultural heritage YANG Zhanbin,XU Ya 2019, 9 (3):  320-324.  doi: 10.12153/j.issn.1674-991X.2018.11.070 Abstract ( 69 )   HTML ( 5 )   PDF (760KB) ( 25 )   The cultural relics environment impact assessment is the basic work to carry out environmental protection of cultural relics for construction project. At present, it is difficult to fully measure the comprehensive environmental impact of various factors on cultural relics during the construction and operation of construction projects and the impact level of construction projects on cultural relics. Considering the pollution emission factors during construction and operation of construction projects, and taking the cultural relics protection unit as the evaluation acceptor, a conceptual model of the impact of construction projects on cultural relics was constructed. Through systematic analysis of the main environmental pollution factors affecting the cultural protection unit, a comprehensive influence evaluation system was established, including four levels of essential vulnerability, source characteristics, exposure characteristics and cultural relics value characteristics, with 18 indexes, and the weight of each index was determined based on the combination weighting method. The comprehensive influence of a precast plant construction project in Gansu on the Great Wall Beacon Tower was evaluated by the constructed evaluation index system. It showed that comprehensive evaluation index was 4.160, indicating that the construction project would have a moderate impact on Beacon Tower.
 Study on roof greening model with a medicine and edible homologous crop Perilla frutescens crispa SUN Yixin,ZHANG Yi,ZHU Yan,LI Yong,WEI Yuan,HU Qing 2019, 9 (3):  325-330.  doi: 10.12153/j.issn.1674-991X.2019.03.050 Abstract ( 79 )   HTML ( 6 )   PDF (1212KB) ( 30 )   The test of roof greening was carried out with Perilla frutescens crispa instead of traditional greening plants. The environmental benefits of the roof greening model were preliminarily analyzed by comparing the test room with the control room. The results showed that the roof load produced by using Perilla frutescens crispa and mixed soil for roof greening was lower, which conformed to the safety principle of roof greening buildings. Perilla frutescens crispa had a good effect of sound insulation, noise reduction and temperature preservation. Under the same conditions, the noise level in the test room was 9.9 dB lower than that in the control room on average. The maximum temperature in the test room could be reduced by 1.8 ℃ in the daytime and increased by 0.5 ℃ in the night. Perilla frutescens crispa leaves had a certain adsorption effect on floating dust in the air. The economic value of roof could be effectively exploited by using Perilla frutescens crispa with economic added value to carry out roof greening.
 Progress of cohort studies in the field of environment and health SONG Huan,ZHU Yunjie,XU Qiujin 2019, 9 (3):  331-334.  doi: 10.12153/j.issn.1674-991X.2019.01.290 Abstract ( 260 )   HTML ( 19 )   PDF (751KB) ( 55 )   Environment and health issues are important factors that affect human health and social development, and are also an important environmental protection work currently in China. Considering the unique advantages of cohort study in causality judgments and the increasingly prominent reality of environment-related health problems, the application and development of cohort studies in the field of environment and health were reviewed, the main contents of cohort study in the field of environment and health described, and the necessity of further cohort study put forward. Meanwhile, the opportunities and challenges of the large-scale cohort study on environment and health in China were also analyzed, so as to provide a diversified perspective and a more reasonable analytical framework for the application of cohort study in the field of environment and health.