2021 Vol. 11, No. 5

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2021, 11(5): .
Abstract:
Idea and system of compiling Technical Guidelines for Water Purification by Constructed Wetlands
Shaoyong LU, Zhengfen WAN, Xingsheng KANG, Jian ZHANG, Yuming JING, Xia JIANG, Jinyong ZHANG, Shuang LIANG, Yunxiao ZHANG, Jielin LI, Xiaochun GUO, Tianli MA, Kun WANG, Yonghong WU, Fengkai SUN, Moxi XUE, Weijing KONG, Hongbin LU, Huijuan XIA, Jianfeng PENG, Senlin ZHANG, Haowei ZHENG
2021, 11(5): 829-836. doi: 10.12153/j.issn.1674-991X.20210377
Abstract:
Constructed wetland is an important means of water ecological restoration, pollution reduction, ecological space increase and biodiversity improvement. It is of great significance to restore the water ecosystem, provide ecological flow for water bodies, promote the recycling of regional reclaimed water and promote the construction of ecological civilization. On April 30, 2021, the Ministry of Ecology and Environment issued Technical Guidelines for Water Purification by Constructed Wetlands (hereinafter referred to as Guidelines), which aimed to guide local governments in their work related to water purification of constructed wetlands. The background and significance, compiling ideas, main contents and implementation suggestions of the Guidelines were mainly interpreted, and the technical points of the design, construction, acceptance, and operation and maintenance (O&M) of the constructed wetlands purification projects were systematically elaborated. Aiming at the current problems of inconsistent links in design, construction acceptance, operation and maintenance and emphasizing construction and neglecting maintenance of the constructed wetlands, based on the engineering practice and scientific research results, the important factors affecting the wetland function, purification efficiency and long-term operation were closely focused on in the Guidelines, the climate zoning throughout China was carried out, the design parameters in zoning was put forward, and the technical requirements for construction, acceptance, and O&M were refined, so as to provide ideological reference and technical support for the water purification of constructed wetlands in accordance with local conditions in China.
Ground geotemperature characteristics of fog and haze days and the possible effects of seismic activities in Langfang City
Liping GUO, Meng WANG, Heting WANG
2021, 11(5): 837-844. doi: 10.12153/j.issn.1674-991X.20200255
Abstract:
According to the meteorological observation data about fog, haze, shallow geotemperature, wind direction, wind speed and relative humidity and seismic data of magnitude Ms2.0 or above in Langfang City from 2009 to 2018, the deep analysis was carried out on the characteristics of shallow geotemperature of fog and haze days, and the effects of seismic activities by Yamamoto statistical analysis and mathematical statistics. The results showed that: 1)The occurrence and distribution of fog and haze in Langfang City had both similarities and differences. The distribution of fog fluctuated in a single peak, with peak value in December, while that of haze was bimodal, with peak value in July and January, and July had the biggest value. 2)The distribution and formation of fog and haze were greatly connected with high shallow geotemperature. Once the fog and haze were highly severe at the same time, the characteristics of high geotemperature would be very significant. The average proportion of positive anomalies in geotemperature of 0, 10, 20 and 40 cm under the ground reached over 70%, and the surface temperature was above 80%. 3)There were differences in daily geotemperature characteristics on fog, haze days and their mixture days. The average proportion of positive anomalies in daily geotemperature of mixture of fog and haze was the highest, and the geothermal layers were relatively thick. There was a continuously increase in geotemperature before the formation of haze. And the average proportion of positive anomalies in geotemperature on fog days was higher than that on haze days. 4)The geotemperature was relatively high before and after the earthquake. The more seismicity, the more persistent the characteristic of relatively high geotemperature. The seismicity in 50 km of Langfang City was related to the increase of geotemperature, fog, haze and abnormal distribution of them. The increase of geotemperature caused by seismicity provided beneficial conditions for the formation of fog and haze, and also provided certain basic thermodynamic conditions for the formation of weathers including rainfall and snowfall. The rainfall and snowfall could lead to the decrease of geotemperature for some time.
Research progress of road dust control measures and their efficiency evaluation
Yuefan ZHANG, Jianhua CHEN, Dong LI, Jian GAO
2021, 11(5): 845-854. doi: 10.12153/j.issn.1674-991X.20200280
Abstract:
Road dust is currently the leading source of PM10 emissions from urban traffic in China. Therefore, taking effective measures to control road dust and evaluating the effectiveness of the control measures play an important role in urban atmospheric environmental management, and have great significance for efficiently and accurately reducing road dust emissions. The principle, characteristics, application scope and development history of main control measures on road dust reported in domestic and foreign literature were reviewed. On this basis, the evaluation methods and indicators of various control measures in different studies were introduced, and the effectiveness of different control measures was analyzed and compared. The factors affecting control efficiency were also systematically summarized. It was pointed out that there was a lack of relevant research in China, which met the country’s actual road infrastructure, weather and climate conditions, and urban environmental management measures. In the future, it could be considered to combine the new road dust detection method named TRAKER with the classic method named AP-42 to construct a measurement system for evaluating the efficiency of control measures, so as to determine the most economical and efficient road dust control measures and provide suggestions for urban atmospheric environmental management.
Potential analysis of cleaner production emission reduction of particulate pollution in foundry industry: taking M City as an example
Tingting WANG, Yixin ZHANG, Changbo ZHOU, Yajing GUO, Yan YANG, Jianhua CHEN, Guimei HAN
2021, 11(5): 855-860. doi: 10.12153/j.issn.1674-991X.20210014
Abstract:
Particulate matter is the main air pollutant in foundry industry and one of the key air pollutants controlled by the state. Taking the foundry industry as the research object, the characteristics of generation and emission of particles in various production processes of foundry enterprises were analyzed. Taking the foundry industry in M City, as an example, the emission status of particulate matter and related industrial policies were analyzed and summarized, and the potential of cleaner production emission reduction in the foundry industry of M City was summarized.Combined with the “bottom-up” pollution reduction model and Second National Survey of Pollution Sources Industrial Pollution Coefficient Manual, a model of particulate matter pollution reduction in foundry industry was constructed and, on this basis, the potential of particulate matter pollution reduction in A foundry company during the “14th Five-Year Plan” period was predicted and analyzed.The results showed that compared with the baseline year 2019, the total amount of particulate matter emitted by core making, molding/pouring and sand treatment processes of A foundry company in 2025 is expected to be reduced by 3 807.23 kg, which made the enterprise had a direct understanding of the emission reduction effect brought by the promotion and popularization of cleaner production technology. At the same time, five measures were put forward to prevent and control particulate pollution in foundry industry, which could provide reference for the development planning of pollution reduction in foundry industry during the “14th Five-Year Plan” period.
Optimal grid scale and sampling design optimization method for heavy metal pollution investigation in farmland soil
Xuzhi QIN, Hanwen ZHENG, Ruicheng HE, Wenjuan DING, Jun ZHANG, Guannan CUI, Peili SHI, Yunfeng XIE
2021, 11(5): 861-868. doi: 10.12153/j.issn.1674-991X.20200303
Abstract:
In order to explore the optimal grid scale and sampling design optimization method for soil heavy metal pollution investigation, soil samples were collected and analyzed in farmland near an old industrial park in central and southern China. Four meshes of different scales, including 70 m×70 m, 100 m×100 m, 160 m×160 m and 200 m×200 m, were constructed, and the estimation accuracy of Cd polluted spatial location in soil was analyzed and verified by estimation test of Matheron moment estimation and geostatistical method. The results indicated that the estimation accuracy of polluted spatial location was similar for 70 m×70 m and 100 m×100 m grid, and higher than 160 m×160 m and 200 m×200 m grid. By encrypting the sampling points on the uncertain region of 100 m×100 m grid, the estimation accuracy of polluted spatial location increased from 78.89% to 86.25%, and the number of investigation samples decreased by 35% for 70 m×70 m grid, not only reducing the cost of sampling and testing, but also improving estimation accuracy of polluted spatial location effectively.
Prediction of construction and demolition waste production based on material flow analysis
Min ZHANG, Li DONG, Jingyang LIU, Yingying BI, Jianqiang ZHANG, Minghui DU
2021, 11(5): 869-878. doi: 10.12153/j.issn.1674-991X.20210060
Abstract:
In response to the rapid increase in the amount of construction and demolition waste (C&DW) and the lack of statistical data on the output of C&DW, based on the 1stOpt fitting platform and Visual Basic programming software, a dynamic prediction model of urban residential and non-residential construction waste was constructed, and the changing trend of C&DW production and its compositions under three scenarios of short lifetime, medium lifetime and long lifetime quantitatively simulated. The results showed that: The stock area of urban residential buildings and non-residential buildings in China would reach their peaks in 2058 and 2064, respectively, with the peaks of 65.74 billion m2 and 56.94 billion m2. Under the short lifetime, medium lifetime and long lifetime scenarios, the construction area of residential and non-residential buildings would reach their peaks in 2020s, and the demolition area would peak in the second half of this century. The total output of China’s urban residential C&DW would reach its peak in 2072, 2081 and 2100 under the three scenarios of short lifetime, medium lifetime and long lifetime, respectively, with peaks of 2.869 billion tons, 2.171 billion tons and 1.65 billion tons. Under the three scenarios, the total output of non-residential C&DW would reach peaks in 2077, 2084 and 2100, with a total output of 2.625 billion tons, 2.029 billion tons and 1.548 billion tons, respectively. Before 2000, C&DW was mainly composed of construction waste. After 2000, demolition waste was the main composition. By 2100, the proportion of demolition waste would reach 98%. Among them, concrete, bricks, and steel accounted for 44%-71%, 22%-51%, 0.50%-2.89%, and other compositions accounted for about 2.76%-4.68%. Taking into account the development trend of construction flow and the characteristics of C&DW generation, the government departments should slow down the growth rate of per capita building area through macro-control, prolong the service life of buildings, improve the recycling rate of C&DW and the market consumption of secondary buildings materials, so as to cut down the output of C&DW and reduce their damage to the ecological environment.
Study of bacterial community structure characteristics in humus soils of different landfill ages
Shuai PENG, Xiaoguo CHEN, Xiaoguang LI, Guowen LI, Wei LI, Caole LI, Yingzhi HAO, Jiaxi LI
2021, 11(5): 879-887. doi: 10.12153/j.issn.1674-991X.20210147
Abstract:
In order to explore the effect of landfill time on the bacterial community structure of humus soil, taking humus in a domestic waste landfill in Jiangsu Province, China as the research object, Illumina Miseq high-throughput sequencing technology was used to analyze the bacterial community composition of humus and the surrounding soil with landfill time of 1-3 years, 3-6 years and 6-10 years. The results showed that the richness and diversity of the bacterial community in humus soil increased with the landfill time, but they were lower than those in the surrounding soil. Non metric multidimensional scaling (NMDS) analysis showed that the bacterial community structure difference was bigger in humus soil of different landfill time, but the similarity between the bacterial community in the soil surrounding the landfill site and the humus soil buried for 6-10 years was relatively high, which may be caused by the surrounding soil being polluted by landfill leachate to some extent. Firmicutes, Proteobacteria, Actinobacteriota, Chloroflexi and Bacteroidota were the dominant phylum in humus soil at each stage. The relative abundance of Firmicutes increased first and then decreased with the landfill time, the change of Chloroflexi was the opposite. The relative abundance of Bacteroidetes decreased at the later stage of landfill, while the relative abundance of Proteobacteria and Actinobacteria did not change significantly during the whole process. Redundant analysis (RDA) results showed that the change of bacterial community structure in humus soil was closely related to total nitrogen (TN), heavy metals (Cd, Zn) and pH.
Study on the public single-use plastics reduction policies based on the theory of environmental behaviors
Jiaxu ZHANG, Yixiang DENG, Chenglong ZHANG, Chenlin HAO
2021, 11(5): 888-897. doi: 10.12153/j.issn.1674-991X.20200300
Abstract:
The public behavioral psychology is a key factor for the efficiency of the single-use plastics reduction policies. In order to formulate differentiated single-use reduction policies and measures, a single-use plastic reduction behavior intention model was established based on Theory of Planned Behavior (TPB) and Normative Activation Theory (NAM) of environmental behavior theory. Then the questionnaires were formulated based on this model. 408 valid questionnaires were obtained from different groups by the means of online and offline investigation. And AMOS software was used to analyze the structural equation model. It showed that the awareness of the pollution consequences of (micro)plastic pollution had a significant positive impact on the public intention to reduce the use of single-use plastics, so the government should enhance the propagation of the environmental impact of (micro)plastic pollution, especially to make the public feel its negative effects on the personal health. The survey results also showed that the positive attitudes of the investigated persons to reduce the use of single-use plastic products had no significant impacts on their behaviors, and therefore the mechanism of rewards and penalties for single-use plastic reduction behavior was necessary to increase the public initiatives to reduce the single-use plastics.
Investigation of food wastage in different types of restaurants in China and analysis of its influencing factors
He LI, Mingxiao LI, Fanhua MENG, Chengze YU, Yan HAO, Jiaqi HOU
2021, 11(5): 898-907. doi: 10.12153/j.issn.1674-991X.20200290
Abstract:
At present, with the rapid development of catering industry, food wastage is becoming more and more serious. The students and working class who were born in 2000-2010 and 1960-1999 and whose food consumption were less than 3 000 yuan every month, were taken as consumer groups to investigate the current situation and their awareness factors of food wastage in different types of restaurants by questionnaire surveys conducted in traditional restaurants, buffets, fast food and snacks. Excel, SPSS and other software combined with mathematical statistics theory were used to analyze the status and causes of food wastage. Structural equation model combined with planned behavior theory were used to analyze and predict the willingness of food wastage, and Receiver Operating Characteristic (ROC) was also used to verify the fitting effect of the prediction probability model of the factors affecting consumer awareness. The results showed that the order of food wastage in different types of restaurants was traditional restaurant > cafeteria > fast food and snacks. Business meal was the main reason for consumers to waste food, due to the dishes were not suitable for appetites or too heavy to finish. In addition, it was found that men are more likely to waste food than women. The consumers born in 2000-2010 and 1990-1999 had a higher degree of food wastage, and the proportion of food waste was gradually decreasing with the increase of ages. Through the analysis and prediction of structural equation model, it showed that personal behavior attitude and perceive behavior control indirectly affected the consumers’ behavior intention of food wastage. Therefore, food wastage could be alleviated by guiding and improving consumers’ awareness and attitude. The study found that the ways to reduce food wastage included packing leftovers, and choosing foods that were easy to store and self preference, etc. For restaurants operators, they were suggested to actively guide consumers’ awareness of diligence and frugality and packaging of leftover meals by providing exquisite gifts and establish membership systems to alleviate food wastage.
Pollution characteristics and risk assessment of heavy metals in Tianjin Lingang Coastal Wetland Park
Xiangju MA, Huitao XU, Liping WANG
2021, 11(5): 908-918. doi: 10.12153/j.issn.1674-991X.20200281
Abstract:
To understand the pollution characteristics and environmental risks of heavy metals in Tianjin Lingang Coastal Wetland Park, water and sediments were collected and the concentrations of six common heavy metals in the coastal water of Tianjin including Cu, Pb, Zn, Cd, Cr and As were detected and analyzed. The heavy metal pollution index (HPI) and the species sensitivity distribution (SSD) methods were used to assess the risk of heavy metal pollution in overlying water, the geoaccumulation index (Igeo), and the potential ecological risk index (RI) methods were used to assess the heavy metal pollution risk in sediments. The results showed that only Cr, Cu, Zn, and As were detected in water, and the mean concentration value was 50.93, 2.56, 38.21 and 8.67 μg/L, respectively. The concentrations of Cu, Zn, and As at each sampling site were within Grade Ⅳ water quality standard of Environmental Quality Standards for Surface Water(GB 3838-2002 ). All of the six heavy metals were detected in the sediments, and the mean concentration value was 66.28, 24.12, 91.37, 9.83, 0.88 and 20.38 mg/kg, respectively. The concentration of Cr, Cu, Zn and Cd exceeded the standard values of soil environmental background concentration in China in different levels. For the risk assessment of heavy metals in water, the assessment result of HPI indicated a low pollution level, and the main polluting element was Cr; the risk assessment using SSD evaluation showed a medium-high risk level and the main polluting element was As causing high risk. For sediments, the risk assessment using Igeo showed that Cd was in medium-polluting level, but Cr, Cu, Zn, As and Pb were in non or light polluting level; the risk assessment using RI showed that the ecological risk ranged from medium to high level. The risk results of different methods were different clearly due to the difference of reference state, risk acceptor or protected object. In order to protect the ecological system more strictly and effectively, the results of high risks should be accepted to take pollution prevention measures.
Main applications of isotope technology in groundwater study
Baoqiang MA, Xiao WANG, Chao TANG, Li LI, Jianyuan MA, Xuhua MIAO
2021, 11(5): 919-926. doi: 10.12153/j.issn.1674-991X.20200263
Abstract:
The main applications of isotope technology in groundwater research were reviewed, including tracing groundwater recharge sources and water rock interaction, identifying groundwater pollution sources and estimating groundwater age and renewability. The application of stable hydrogen and oxygen isotopes to trace the source of groundwater recharge had become an important aspect of groundwater recharge study. It was helpful to understand the origin of groundwater quality and hydrogeochemical process by analyzing and studyingthe variation of 87Sr/86Sr、26Mg isotopes in groundwater. Isotope technology had unique value in identifying the source of groundwater pollution, for instance the nitrate source in groundwater could be identified by nitrogen and oxygen isotope (15N and 18O)of nitrate. The application of radioisotopes such as 3H and 14C could not only get the groundwater age, but also help to understand the groundwater circulation and renewability, which was an important reference index for sustainable development and utilization of groundwater.
Study on the efficacy of micron zero-valent iron on phosphate removal and its mechanism
Zhiqiang JIAN, Gaoting ZHOU, Bin GONG, Ying ZHAO
2021, 11(5): 927-934. doi: 10.12153/j.issn.1674-991X.20210027
Abstract:
In order to study the effect and its mechanism of phosphate removal by micron zero-valent iron (mZVI), some important water chemistry parameters which affected the removal efficiency of phosphate were investigated firstly. Then, the phosphate removal efficiency by mZVI and the dynamics distribution of phosphate in the corrosion products of mZVI including magnetic iron oxide and suspended iron oxide were studied, and the changes of physical and chemical parameters (pH, DO, ORP) during the reaction process were monitored and the reaction process in the system further analyzed. Finally, the reaction products were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectrometer (XPS) and other characterization methods. The results showed that lower pH could significantly increase the reactivity of mZVI and accelerate the removal of phosphate. The increase of ionic intensity could accelerate the reaction rate of mZVI. AsO 4 3 - and SiO 3 2 - had a significantly inhibitory effect on the phosphate removal, while NO 3 - and CO 3 2 - were the opposite and SO 4 2 - had little effect on it. The content of the removed phosphate in the magnetic solid was equivalent to that in the suspended solid. SEM analysis of the reaction product showed that the morphology of the solid surface under the phosphate and non-phosphate conditions was different. XPS analysis indicated that Fe2+ and Fe3+ were mainly produced on the phosphate removal by mZVI. The 1,10-phenanthroline masking experiment evidenced that the combination of phosphate and Fe2+was the main way to remove phosphate by mZVI. The XRD results showed that phosphate precipitated with Fe2+ as H2FeP2O7, which proved that precipitation existed during phosphate removal by mZVI.
Research progress of greywater treatment technology at home and abroad
Yun LI, Zhiqin HE, Xunfeng XIA, Sheng CHEN
2021, 11(5): 935-941. doi: 10.12153/j.issn.1674-991X.20200301
Abstract:
The collection and treatment of domestic wastewater by quality, especially the treatment and reuse of greywater,can realize the resource utilization of wastewater and save energy. Firstly, the basic concept of quality-based separation and collection of domestic wastewater and the characteristics of greywater quality and quantity were introduced. The research progress of greywater treatment technologies, such as filtration, membrane separation, MBR, constructed wetland, ecological filter and so on were reviewed,and the effects of different types of treatment technologies were compared and analyzed. The results showed that single physical treatment technology had limited removal effect on organic matter surfactants and other components. Generally, other treatment technologies needed to be supplemented to achieve the purpose of greywater regeneration and reuse. Chemical treatment technology could effectively remove SS and surfactants in low-intensity greywater. Biological and ecological treatment technologies were two kinds of technologies widely used in greywater treatment, among which constructed wetland and MBR were the two most potential greywater treatment and reuse technologies. Finally, according to the research status of greywater treatment technologies, the research focus in the field of graywater treatment in the future was put forward.
Research progress in Fenton process for treating landfill leachate
Xiangru WANG, Liping WU, Guoxian HUANG, Shengwang GAO, Ziqiang TIAN, Qinghuan ZHANG, Chaoke YANG
2021, 11(5): 942-950. doi: 10.12153/j.issn.1674-991X.20200299
Abstract:
Conventional treatment processes are difficult to completely degrade and remove the toxic and harmful pollutants in landfill leachate. Therefore, advanced oxidation processes are needed to further treat the landfill leachate. Fenton process and its derived processes are competitive in the treatment of landfill leachate. Focusing on the principles, treatment effect and technical development of Fenton process and its derived processes for the treatment of landfill leachate, the latest research progress of this technology was reviewed, and its development history, key technical steps and latest technology application trends were tracked. The advantages and disadvantages of different derivative processes were compared and analyzed. Based on different landfill leachate and corresponding optimal process conditions, and considering comprehensively the problems of safety, economic feasibility and high removal rate, it was pointed out that the compound method and those combined with other processes had better treatment effect and application value. The application prospects and key research directions of Fenton process for the treatment of landfill leachate were prospected, in order to provide a reference for the research, development and popularization of this method for the treatment of landfill leachate.
Research progress of the detection methods of di(2-ethyl hexyl) adipate
Zhuowei ZHANG, Yin YU, Changyong WU, Yuexi ZHOU, Lirong LI, Dianjia LIU, Hongbo XI, Yuanfang NIU
2021, 11(5): 951-961. doi: 10.12153/j.issn.1674-991X.20200248
Abstract:
Di(2-ethyl hexyl) adipate (DEHA) has been widely used as a plasticizer. As a kind of biological endocrine interferon, its long-term use in large quantities would cause adverse effects on human beings and the environment. The detection methods of DEHA were reviewed, including the pretreatment technologies and detection technologies. The pretreatment technologies mainly included Soxhlet extraction, ultrasonic extraction, isotope dilution, top air extraction, liquid-liquid extraction, solid phase micro extraction, and microwave extraction methods, etc. The detection techniques mainly included spectral analysis, gas chromatography, liquid chromatography and their combined analysis methods, etc. The principles, characteristics and applications of different detection technologies were summarized and compared. It was proposed that subsequent studies could be carried out from the aspects of selecting the types of extractive agents for liquid-liquid extraction, combining extraction technologies such as ultrasound, improving DEHA detection ability in complex sample systems, and developing portable intelligent detection instruments.
Numerical simulation of temperature drop and residual chlorine effect on water environment in LNG receiving station: a case study in Dongwu port area of Meizhou Bay
Lu WANG, Lehang XIONG, Yuan ZHANG, Yan CHEN, Shuqin MA, Xiaojiao ZHANG, Rui XIA
2021, 11(5): 962-969. doi: 10.12153/j.issn.1674-991X.20210007
Abstract:
During the operation of LNG receiving station, the cold water is discharged into the sea. The temperature drop of the cold water and the residual chlorine have an effect on the temperature field of the water environment and the biological environment of the nearby sea area. In order to understand the diffusion law of cold water discharge in sea water, the effects of LNG cold water discharge on water environment in Dongwu port area of Meizhou Bay were simulated by means of two-dimensional hydrodynamics-water quality numerical coupling model (MIKE21) and nested models. On the basis of reliable model verification, the temperature drop envelope and residual chlorine envelope of LNG cold drainage in winter and summer were calculated,so as to judge the rationality of selecting the project location. The results showed that under the condition of temperature drop greater than 0.5 ℃, the cold drainage influence range of LNG receiving station was 0.202 km2, which was about 2.81 km from Meizhou Bay ecosystem reserve and 0.53 km from the nearest breeding area. When the residual chlorine concentration was 0.01 mg/L, the residual chlorine influence range was 0.434 km2 and the maximum influence distance was 0.628 km. The temperature drop and residual chlorine of cold water from LNG receiving station had no direct influence on the sensitive targets around the receiving station, and the location of the water outlet was reasonable.
Design of wind-break walls and their application in Hulunbeier sandy land control
Meirong TIAN, Xinyi FU, Weichao YANG, Chaoyang FENG, Jixi GAO
2021, 11(5): 970-975. doi: 10.12153/j.issn.1674-991X.20200287
Abstract:
The grassland desertification is serious in Hulun Lake Basin. 5 different heights and hole types of movable wind-break walls (Ⅰ:2.0 m high, stripe-shaped holes, Ⅱ:1.5 m high, stripe-shaped holes, Ⅲ:1.0 m high, stripe-shaped holes, Ⅳ:1.0 m high, square holes, Ⅴ:1.0 m high, circular holes) were developed and designed as sand barriers in order to explore the ecological restoration modes in serious desertification patches. The windbreak effects of wind-break walls were compared and the characteristics of wind speed at different distances and heights from the surface and surface soil moisture content behind them were determined, which could provide references for the installation of wind-break walls in areas with frequent winds. The results showed that, all wind-break walls could reduce the wind speed within limit distance and the windbreak effect at 0.5 m from the surface were higher than that at 1.0 m. At the distance of 1 m behind the wind-break walls and the height of 0.5 m from the surface, the windbreak effects were Ⅴ(87.30%)>Ⅰ(83.91%)>Ⅱ(83.29%)>Ⅳ(80.20%)>Ⅲ(74.66%). The order of water holding capacity of surface soil was Ⅴ>Ⅰ>Ⅱ>Ⅳ>Ⅲ and the cost of them was Ⅰ>Ⅱ>Ⅴ>Ⅳ>Ⅲ. Therefore, the structural parameters of the wind-break walls that were more suitable for Hulun Lake Basin were as follows: 1.5 m high, stripe-shaped holes; 1.0 m high, circular holes.
Research on water pollution control technology assessment in zinc smelting industry based on AHP-FCE
Jiuli RUAN, Yibo WANG, Yuwen GUO
2021, 11(5): 976-982. doi: 10.12153/j.issn.1674-991X.20210032
Abstract:
The evaluation index system of water pollution control technology of zinc smelting industry was constructed, the analytic hierarchy process-fuzzy comprehensive evaluation (AHP-FCE) model was developed, and the evaluation standards of water pollution control technology of zinc smelting industry were established in two technical units: the complete set of pollution control technology for waste acid and acid wastewater and the complete set of comprehensive wastewater treatment and reuse technology. Then the comprehensive quantitative evaluation of eight pollution control technologies in two technical units was carried out based on AHP-FCE. The results showed that: The comprehensive evaluation score of the key technology of waste acid resource treatment based on “selective adsorption-gas-liquid enhanced sulphidation-evaporation concentration-fluorine chlorine separation” was 4.38, which was the best of the four waste acid and acid wastewater pollution control technologies; the comprehensive evaluation score of the heavy metal smelting wastewater biophysical and chemical combination treatment and reuse technology based on “biological agent advanced treatment technology of heavy metal wastewater” was 4.14, which was the best of the four comprehensive wastewater treatment technologies. The evaluation results couldprovide a reliable basis for enterprises to choose suitable water pollution control technology, and also provide a strong support for the management department to recommend the best feasible technology and formulate relevant policies and standards.
Evaluation and analysis of ecological footprint and carrying capacity of the mainstream of Weihe River in Gansu Province
Fei WEN, Yuehua SHAO, Cunfeng TAN
2021, 11(5): 983-991. doi: 10.12153/j.issn.1674-991X.20210236
Abstract:
As the largest tributary of the Yellow River, the Weihe River occupies an important position in the governance and development of the Yellow River. The ecological footprint and ecological carrying capacity of the mainstream of Weihe River in Gansu Province from 2009 to 2019 were calculated by applying the improved three-dimensional ecological footprint method, the impact of social and economic activities in the basin on the ecological environment was studied, and the measures aimed at promoting the high-quality development of the river basin was explored. The results showed that from 2009 to 2019, the fossil energy land and cultivated land were the largest components of the ecological footprint in the basin of Weihe River in Gansu, which reached 36 498.64 and 12 869.88 hm2 taking provincial hectare as the area equivalent, respectively. The ecological footprint and ecological carrying capacity showed a trend of expanding initially and then shrinking, the proportion of ecological natural resource supply in the regional consumption capacity increased from 13.92% to 15.16%, and the ecological deficit per capita constantly declined at a rate of 2.95% per year. The breadth and depth of ecological footprint increased notably, showing that the unreasonable consumption structure of natural resources has been alleviated, but the mitigation trend of the pressure on the ecological environment in the basin was not obvious. To alleviate the regional ecological pressures, measures such as increasing ecological land, readjusting industrial structure, and optimizing resource consumption structure should be taken in the future.
Application of smart environmental protection system in environmental management
Xinru LI, Min ZHOU, Yidong MI, Hailei SU, Haiyan CHEN, Fanfan WANG, Shuo YANG, Yaqin SHEN, Yuan WEI
2021, 11(5): 992-1003. doi: 10.12153/j.issn.1674-991X.20200282
Abstract:
With the approaching of the era of big data, the smart environmental protection system has become an important theoretical support of promoting the modernization of environmental governance capabilities and governance systems. Establishing a sound smart environmental protection system is an inevitable requirement and important measure to further improve the efficiency of environmental governance in China. Applying the rapidly developing Internet of Things technology to environmental governance, establishing an intelligent environmental data acquisition and processing analysis system, making reasonable decisions and improving the efficiency of environmental management, are the key measures to establish and improve smart environmental system. The combination of smart environmental system and urban environment governance could effectively monitor urban pollution sources, ecological management and other environmental problems in many fields on time, and could help make prompt emergency response and decision-making to the environmental problems that may arise. The overall structure of the smart environmental protection system and the standard system that supported the entire system were systematically introduced. At the same time, the difficulties encountered in the construction of the smart environmental protection system was put forward, and the application smart environmental protection system in different fields of environmental governance and protection was analyzed, in order to provided suggestions and references for the future application of smart environmental protection system in more aspects of environmental governance and management.
Key problems and countermeasures of precise management and control of hazardous waste in coking industry
Yaqiong HAO, Qi ZHOU, Yufei YANG, Hao WU
2021, 11(5): 1004-1011. doi: 10.12153/j.issn.1674-991X.20210099
Abstract:
A great deal of waste gas, waste water and hazardous waste are produced in the coking process. Coking industry is a heavy pollution industry and key control industry in China. The precise control and safe utilization and disposal of hazardous waste in coking industry can not only improve the ecological environment, but also protect people’s health. The present situation of hazardous waste in coking industry was that there were numerous nodes, multiple kinds, large amount and various kinds of pollutants. There were three main ways of utilization and disposal, which were to extract a variety of chemical raw materials from high temperature coal tar and medium-and-low temperature coal tar, to extract salt and acid from desulfurization waste liquid, and to carry out cement kiln collaborative disposal and incineration disposal of the coking hazardous waste which could not be effectively utilized at present. The main problems existing in the current utilization and disposal methods were analyzed. Some suggestions on improving the utilization rate of coking hazardous waste and strengthening the safe disposal were put forward, which mainly included three aspects: 1) In order to promote the utilization of high temperature coal tar and medium-and-low temperature coal tar, the exemption conditions of utilization link in List of Hazardous Waste Exemption Management should be followed. 2) Through the formulation of pollution control standards or technical specifications, “point-to-point” utilization, development of efficient salt extraction and acid production technology, and park unified planning and centralized utilization, the level of salt extraction and acid production from desulfurization waste liquid could be improved. 3) Under the premise of controllable environmental risk, new dry process rotary kiln technology and scientific compatibility of hazardous waste, the coking hazardous waste which could not be effectively utilized at present could be disposed by cement kiln combined disposal and incineration.
Generation and pollution characteristics of hazardous wastes from smelting of copper, lead and zinc in China
Fei WANG, Manli ZHANG, Xuejiao WANG, Tong ZHAO, Yufei YANG
2021, 11(5): 1012-1019. doi: 10.12153/j.issn.1674-991X.20210080
Abstract:
There are a variety of processes and reactions and numerous kinds of wastes in the non-ferrous metal smelting industry, and the links generating wastes are quite different. It is easy to cause some problems such as the difficulty in identifying waste generation nodes, unclear waste direction, unclear pollution characteristics, and so on, in the process of management and control of such hazardous wastes, thus leading to misjudgment in management. By sorting out and analyzing the sources of 22 kinds of copper, lead and zinc smelting wastes in HW48 in National Catalogue of Hazardous Wastes (NCHWs 2021) and the pollution characteristics of key wastes, such as lead skim and arsenic slag, the waste direction was identified. Finally, suggestions were put forward for improving the management of hazardous wastes from smelting of non-ferrous metals in China.
Analysis of solid waste generation nodes and environmental management in the synthetic resin industry
Tong ZHAO, Yi LIU, Meijia LIU, Tingting LIU, Fei WANG
2021, 11(5): 1020-1026. doi: 10.12153/j.issn.1674-991X.20210079
Abstract:
The amendments of Law of the People’s Republic of China on Prevention of Environmental Pollution Caused by Solid Wastewas implemented on Sep. 1 2020, in which enterpriseself-management in the management of industrial solid waste was strengthened and requirements of overall process management were put forward. Synthetic resin industry in China occupies an important position in the industrial circle. The production enterprises are mainly large petrochemical enterprises, which have the ability and responsibility to scientifically manage solid waste and realize the harmless, reduction and resource utilization of solid waste. The production process and node characteristics of polyethylene, polypropylene and polyvinyl chloride in synthetic resin industry were introduced. The generating nodes, waste attributes and management measures of solid waste were elaborated in detail, the generated solid wastewere classified and ordered, the treatment measures of the solid waste in enterprise were summarized, and suggestions for the present status of solid waste generation in synthetic resin industry were proposed, so as to provide scientific basis for the environmental management of hazardous waste and dynamic revision of National Hazardous Waste List in China,and to provide guidance for the self-management of enterprises.
Generation nodes and disposal status of hazardous wastes from metal surface treatment process
Tingting LIU, Tong ZHAO, Jian WANG, Zechun HUANG, Haihui FU
2021, 11(5): 1027-1033. doi: 10.12153/j.issn.1674-991X.20210082
Abstract:
It is difficult to manage hazardous wastes in the metal surface treatment industry because of the wide variety of hazardous wastes, the great hazards, the unclear identification of hazardous waste production nodes and the weak awareness of hazardous waste management in the production enterprises. The most used technologies including electroplating, electroless plating, anodic oxidation, phosphating, and passivation processes were selectedand analyzed. By combing the process flow and comparing with National Hazardous Waste List (version 2021), the production nodes, characteristics, and rules of hazardous waste in each process were analyzed. In addition, the generation, disposal process and disposal status of main hazardous wastes were investigated, and reasonable suggestions were put forward for the management and disposal of hazardous wastes in metal surface treatment process in the future. The research results had important reference significance for the realization of source reduction and harmless disposal of hazardous wastes in metal surface treatment industry.
Current situation for utilization and disposal and environmental management of fly ash from municipal solid waste incineration
Hao WU, Hongbo LIU, Shulei TIAN, Guilan LU, Yaqiong HAO
2021, 11(5): 1034-1040. doi: 10.12153/j.issn.1674-991X.20210083
Abstract:
With the rapid increase of municipal solid waste (MSW), the output of fly ash from MSW incineration is increasing day by day. In 2018, fly ash output reached 3.055 million to 5.092 million tons. Fly ash was considered as a kind of hazardous waste because it contained toxic and harmful substances such as heavy metals with high leaching concentration and dioxin with high toxic equivalent. According to the characteristics of fly ash from domestic waste incineration, the resource utilization and harmless disposal technologies of fly ash were introduced in detail, and the advantages and disadvantages of technologies were summarized. Combined with the environmental management requirements of MSW incineration fly ash, the specific reasons for the incomplete landfill management system, the lack of standards and specifications in the utilization and disposal process, and the limited treatment and disposal technologies of fly ash were analyzed. In order to strengthen the environmental management of fly ash and improve the level of its resource utilization, it was proposed to enhance the comprehensive control of the environmental pollution of fly ash, strengthen the supervision and management of the prevention and control of fly ash pollution, and strengthen the research and development and promotion of the resource utilization technology of fly ash.