In its urbanization course, China is faced with a scarcity of water resources in terms of both water quantity and quality. The development of water industry is a fundamental way to alleviate water shortage. Influenced...In its urbanization course, China is faced with a scarcity of water resources in terms of both water quantity and quality. The development of water industry is a fundamental way to alleviate water shortage. Influenced by the traditional planned economy, Chinas urban water industry has been mainly owned and run by local municipal governments. Their tight fiscal budgets have led to very inadequate investments in water industry and thus, caused a slow development of water industry. In this case, restructuring urban water industry is very important. Based on the discussion concerning the trend of demand for and supply of urban water resources, this paper explores such strategic issues as water industry organization and integrated approaches addressing water scarcity. These are followed by a discussion of introducing market mechanism for restructuring water industry.展开更多
Natural monopoly,because of its spontaneous or natural characteristics, must have some mysterious causes of reasonableness.Thus,the regulations to its efficiency loss would have a different way compared to other monop...Natural monopoly,because of its spontaneous or natural characteristics, must have some mysterious causes of reasonableness.Thus,the regulations to its efficiency loss would have a different way compared to other monopolies. That the characteristics of natural monopoly,in the case of water industry, are that the infrastructure investments are very large,most of which are used to build the transportation system? The webs for transporting their products to their customers,and the products are identity goods or services.By examining the characteristics of natural monopoly,this paper proposed away to break upand remodel the industry of“natural monopoly”.The main clue of remodeling is that the governments,who represent the public and who have the power to control over public resources,should build and maintain a public web platform for the goods’ transportation uses, and break up the barrier ofthe entry so as to produce a market-oriented competitive structure.The running modeland the condition of remodeling are put forward and the cost-revenue analysis of the operation is briefly under consideration.展开更多
Started with the discussions on the value orientation of urban water supply industry marketization,the article points out that the current urban water supply industry marketization reform is inconsistent with the goal...Started with the discussions on the value orientation of urban water supply industry marketization,the article points out that the current urban water supply industry marketization reform is inconsistent with the goal of public water service equalization to some extent.The article also analyzes the problems emerged in urban water supply industry marketization reform and various rea-sons in view of efficiency and fairness.An efficiency and fairness oriented management model is built in this article to illustrate how the government should conciliate interests of various communities involved in the process of marketization reform of the urban water supply industry so as to actualize the coordination of efficiency and fairness.At the end,an assumption on urban water price is put forward to help achieve the public water service equalization.展开更多
Developing effective and practical electrocatalyst under industrial electrolysis conditions is critical for renewable hydrogen production.Herein,we report the self-supporting NiFe LDH-MoS_(x) integrated electrode for ...Developing effective and practical electrocatalyst under industrial electrolysis conditions is critical for renewable hydrogen production.Herein,we report the self-supporting NiFe LDH-MoS_(x) integrated electrode for water oxidation under normal alkaline test condition(1 M KOH at 25℃)and simulated industrial electrolysis conditions(5 M KOH at 65℃).Such optimized electrode exhibits excellent oxygen evolution reaction(OER)performance with overpotential of 195 and 290 mV at current density of 100 and 400 mA·cm^(-2) under normal alkaline test condition.Notably,only over-potential of 156 and 201 mV were required to achieve the current density of 100 and 400mA·cm^(-2) under simulated industrial electrolysis conditions.No significant degradations were observed after long-term durability tests for both conditions.When using in two-electrode system,the operational voltages of 1.44 and 1.72 V were required to achieve a current density of 10 and 100 mA·cm^(-2) for the overall water splitting test(NiFe LDH-MoS_(x)/INF||20%Pt/C).Additionally,the operational voltage of employing NiFe LDH-MoS_(x)/INF as both cathode and anode merely require 1.52 V at 50mA·cm^(-2) at simulated industrial electrolysis conditions.Notably,a membrane electrode assembly(MEA)for anion exchange membrane water electrolysis(AEMWEs)using NiFe LDH-MoS_(x)/INF as an anode catalyst exhibited an energy conversion efficiency of 71.8%at current density of 400 mA·cm^(-2)in 1 M KOH at 60℃.Further experimental results reveal that sulfurized substrate not only improved the conductivity of NiFe LDH,but also regulated its electronic configurations and atomic composition,leading to the excellent activity.The easy-obtained and cost-effective integrated electrodes are expected to meet the large-scale application of industrial water electrolysis.展开更多
Despite the endemic drought, arid climate and associated limited freshwater resources, as well as difficult geopolitical realities, Israel can provide a reliable supply of high quality water to a rapidly growing popul...Despite the endemic drought, arid climate and associated limited freshwater resources, as well as difficult geopolitical realities, Israel can provide a reliable supply of high quality water to a rapidly growing population. The achievements of water supply in Israel can be summarized as water technologies (like water transportation and purification, desalination, wastewater treatment, effluent reuse, storm water catchment, control systems, rain enhancement and drip irrigation, etc.), water management and legislation as well as water industry. In view of the national concern regarding the quality and quantity of the water, the skills, technologies and know-how that Israel has accumulated in water supply and irrigation can give us enlightenment that is also presented in this paper.展开更多
Amorphous alloy(MGs)is a solid alloy with disordered atomic accumulation obtained by ultra-rapid solidification of alloy melt.The atom deviates from the equilibrium position and is in metastable state.Up to now,a larg...Amorphous alloy(MGs)is a solid alloy with disordered atomic accumulation obtained by ultra-rapid solidification of alloy melt.The atom deviates from the equilibrium position and is in metastable state.Up to now,a large number of MGs have been applied to the treatment of dye and heavy metal contaminated wastewater and ideal experimental results have been obtained.However,there is no literature to systematically summarize the chemical reaction and degradation mechanism in the process of degradation.On the basis of reviewing the classification,application,and synthesis of MGs,this paper introduces in detail the chemical reactions such as decolorization,mineralization,and ion leaching of Fe-based amorphous alloy(Fe-MGs)in the degradation of organic and inorganic salt wastewater through direct reduction or advanced oxidation mechanism.Compared with crystalline materials,the higher reaction rate of Fe-MGs can be attributed to lower activation energy,negative redox potential,loose product layer,and band structure with downward shift of valence band top.Finally,some suggestions and prospects are put forward for the limitations and research prospects of MGs in the environmental field,which provides a new idea for the synthesis of new environmental functional materials.展开更多
The paper presents a flow plasma reactor permitting modification of the properties of water/aqueous solutions by stochastic resonance amplification of vibrations of selected chemical species in water with electromagne...The paper presents a flow plasma reactor permitting modification of the properties of water/aqueous solutions by stochastic resonance amplification of vibrations of selected chemical species in water with electromagnetic noise generated during a plasma discharge. The main parameters characterizing the quality for super-pure water, tap water and water from the intake in Besko (Poland) before and after the process in the plasma reactor were presented for comparison. In addition, the <sup>17</sup>O NMR (the full width at half maximum) and electrospray ionization mass spectrometry (ESI MS) methods were used to determine differences in physicochemical parameters between the untreated and plasma-treated water. It has been established that the water subjected to plasma treatment shows much different gas absorption properties than the untreated water samples, as a function of temperature and pressure, in this paper we report exemplary data for CO<sub>2</sub>, oxygen and acetylene. The improved gas absorption properties of the plasma-treated water make it attractive for the use in industrial processes. It is worth pointing to a great capacity of the new reactor (4000 l/h), and low energy consumption (20 MJ/h) for the treatment of the above mentioned volume flow rate of water.展开更多
Metal–organic frameworks have garnered attention as highly efficient pre-electrocatalysts for the oxygen evolution reaction(OER).Current structure–activity relationships primarily rely on the assumption that the comp...Metal–organic frameworks have garnered attention as highly efficient pre-electrocatalysts for the oxygen evolution reaction(OER).Current structure–activity relationships primarily rely on the assumption that the complete dissolution of organic ligands occurs during electrocatalysis.Herein,modeling based on NiFe Prussian blue analogs(NiFe-PBAs)show that cyanide ligands leach from the matrix and subsequently oxidize to corresponding inorganic ions(ammonium and carbonate)that re-adsorb onto the surface of NiFe OOH during the OER process.Interestingly,the surface-adsorbed inorganic ions induce the OER reaction of NiFe OOH to switch from the adsorbate evolution to the lattice-oxygen–mediated mechanism,thus contributing to the high activity.In addition,this reconstructed inorganic ion layer acting as a versatile protective layer can prevent the dissolution of metal sites to maintain contact between catalytic sites and reactive ions,thus breaking the activity–stability trade-off.Consequently,our constructed NiFePBAs exhibit excellent durability for 1250 h with an ultralow overpotential of 253 mV at 100 mA cm2.The scale-up NiFe-PBAs operated with a low energy consumption of4.18 kWh m3 H2 in industrial water electrolysis equipment.The economic analysis of the entire life cycle demonstrates that this green hydrogen production is priced at US$2.59 kg^(-1)H_(2),meeting global targets(<US$2.5 kg^(-1)H_(2)).展开更多
Electrosorption technology was used to treat the reused comprehensive wastewater from iron and steel industry. A problem of relatively high conductivity of wastewater which greatly affects the reuse was examined, and ...Electrosorption technology was used to treat the reused comprehensive wastewater from iron and steel industry. A problem of relatively high conductivity of wastewater which greatly affects the reuse was examined, and industrial test was conducted for the reused water advanced deionization and purification in a comprehensive wastewater treatment plant o{ WISCO [Wuhan Iron and Steel (Group) Corporation]. The results of the on-site in- dustrial test showed a satisfactory treatment performance for the reused water even at a flow rate of 1 000 L/h in a standard 500 L/h unit. The average conductivity decreased by about 70%, from 580--780 μS/cm to 100--350 μS/cm. The average removal efficiency of CI and Ca2+ was about 75% and 68%, respectively, and CODcr of the treated wa- ter was also reduced in some degree while the pH value was almost unchanged. The energy consumption was as low as 0.6 kWh/t, which was remarkably superior to the conventional technologies. Therefore, it is entirely feasible that the novel eleetrosorption technology can be used in enhanced desalination and purification treatment of reused com- prehensive wastewater in iron and steel industry.展开更多
A full-scale plant using anaerobic, anoxic and oxic processes (A1/A2/O), along with a pilot-scale membrane bioreactor (MBR), nanofiltration (NF) and reverse osmosis (RO) integrated system developed by Shanghai...A full-scale plant using anaerobic, anoxic and oxic processes (A1/A2/O), along with a pilot-scale membrane bioreactor (MBR), nanofiltration (NF) and reverse osmosis (RO) integrated system developed by Shanghai Baosteel Chemical Co. Ltd., was investigated to treat coking wastewater for industrial reuse over a period of one year. The removals reached 82.5% (COD), 89.6% (BOD), 99.8% (ammonium nitrogen), 99.9% (phenol), 44.6% (total cyanide (T-CN)), 99.7% (thiocyanide (SCN-)) and 8.9% (fluoride), during the A1/A2/O biological treatment stage, and all parameters were further reduced by over 96.0%, except for fluoride (86.4%), in the final discharge effluent from the currently operating plant. The pilot-scale MBR process reduced the turbidity to less than 0.65 NTU, and most of the toxic organic compounds were degraded or intercepted by the A1/A2/O followed MBR processes. In addition, parameters including COD, T-CN, total nitrogen, fluoride, chloride ion, hardness and conductivity were significantly reduced by the NF-RO system to a level suitable for industrial reuse, with a total water production ratio of 70.7%. However, the concentrates from the NF and RO units were highly polluted and should be disposed of properly or further treated before being discharged.展开更多
1.Introduction The current state of the wastewater industry is one of transition.In Europe,in the last 2 decades,we have seen a significant improvement on river water quality after implementation of the Urban Waste Wa...1.Introduction The current state of the wastewater industry is one of transition.In Europe,in the last 2 decades,we have seen a significant improvement on river water quality after implementation of the Urban Waste Water Treatment European Directive(91/271/EEC)[1],and the European Water Framework Directive[2].Up to 97% of the population have now access to safely managed wastewater treatment services.展开更多
Water demand increases continuously with an increasing population and economic development. As a result, the difference between water supply and demand becomes a sig- nificant issue, especially in arid regions. To fig...Water demand increases continuously with an increasing population and economic development. As a result, the difference between water supply and demand becomes a sig- nificant issue, especially in arid regions. To figure out the utilization of water resources in the arid region of northwestern China (ARNWC), and also to provide methodologies to predict the water use in future, three models were established in this study to calculate agricultural irri- gation, industrial and domestic water use in the ARNWC from the late 1980s to 2010. Based on river discharges in the region, the supply and demand of water resources at the river basin level were analyzed. The results indicated that agricultural irrigation demand occupies more than 90% of the total water use in the ARNWC. Total water demand increased from 31.97 km3 in the late 1980s to 48.19 km3 in 2010. Most river basins in this arid region were under me- dium and high water stress. Severe-risk river basins, such as the Shiyang river basin and the eastern part of the northern piedmont of the Tianshan Mountains, were found in this region. It was revealed that the water supply became critical from April to May, which was the season of the lowest water supply as determined by comparing monthly water consumption.展开更多
The paper presents the prediction of total energy production and consumption in all provinces and autonomous regions as well as determination of the variation of gravity center of the energy production, consumption an...The paper presents the prediction of total energy production and consumption in all provinces and autonomous regions as well as determination of the variation of gravity center of the energy production, consumption and total discharge of industrial waste water, gas and residue of China via the energy and environmental quality data from 1978 to 2009 in China by use of GM(1,1) model and gravity center model, based on which the paper also analyzes the dynamic variation in regional difference in energy production, consumption and environmental quality and their relationship. The results are shown as follows. 1) The gravity center of energy production is gradually moving southwestward and the entire movement track approxi-mates to linear variation, indicating that the difference of energy production between the east and west, south and north is narrowing to a certain extent, with the difference between the east and the west narrowing faster than that between the south and the north. 2) The gravity center of energy consumption is moving southwestward with perceptible fluctuation, of which the gravity center position from 2000 to 2005 was relatively stable, with slight annual position variation, indicating that the growth rates of all provinces and autonomous regions are basically the same. 3) The gravity center of the total discharge of industrial waste water, gas and residue is characterized by fluctuation in longitude and latitude to a certain degree. But, it shows a southwestward trend on the whole. 4) There are common ground and discrepancy in the variation track of the gravity center of the energy production consumption of China, and the comparative analysis of the gravity center of them and that of total discharge of industrial waste water, gas and residue shows that the environmental quality level is closely associated with the energy production and consumption (especially the energy consumption), indicating that the environment cost in economy of energy is higher in China.展开更多
China's rapid economic growth poses serious concerns over environmental degradation, especially in the context of higher pollution levels resulting from unprecedented industrial activity. It is commonly held that gov...China's rapid economic growth poses serious concerns over environmental degradation, especially in the context of higher pollution levels resulting from unprecedented industrial activity. It is commonly held that government policies are effective in the form of investment in pollution control and the imposition of a discharge fee on industrial units for the purpose of safety of environmental quality. In this study, we find that government policies do not prove to be successful in controlling air pollution in comparison to water pollution. Furthermore, air pollution is increasing, while water pollution is following a stable, decreasing curve. Hence, some reforms need to be implemented in government policies, particularly those concerning the effectiveness of investment in environmental protection and improving managerial skills in industry.展开更多
文摘In its urbanization course, China is faced with a scarcity of water resources in terms of both water quantity and quality. The development of water industry is a fundamental way to alleviate water shortage. Influenced by the traditional planned economy, Chinas urban water industry has been mainly owned and run by local municipal governments. Their tight fiscal budgets have led to very inadequate investments in water industry and thus, caused a slow development of water industry. In this case, restructuring urban water industry is very important. Based on the discussion concerning the trend of demand for and supply of urban water resources, this paper explores such strategic issues as water industry organization and integrated approaches addressing water scarcity. These are followed by a discussion of introducing market mechanism for restructuring water industry.
文摘Natural monopoly,because of its spontaneous or natural characteristics, must have some mysterious causes of reasonableness.Thus,the regulations to its efficiency loss would have a different way compared to other monopolies. That the characteristics of natural monopoly,in the case of water industry, are that the infrastructure investments are very large,most of which are used to build the transportation system? The webs for transporting their products to their customers,and the products are identity goods or services.By examining the characteristics of natural monopoly,this paper proposed away to break upand remodel the industry of“natural monopoly”.The main clue of remodeling is that the governments,who represent the public and who have the power to control over public resources,should build and maintain a public web platform for the goods’ transportation uses, and break up the barrier ofthe entry so as to produce a market-oriented competitive structure.The running modeland the condition of remodeling are put forward and the cost-revenue analysis of the operation is briefly under consideration.
文摘Started with the discussions on the value orientation of urban water supply industry marketization,the article points out that the current urban water supply industry marketization reform is inconsistent with the goal of public water service equalization to some extent.The article also analyzes the problems emerged in urban water supply industry marketization reform and various rea-sons in view of efficiency and fairness.An efficiency and fairness oriented management model is built in this article to illustrate how the government should conciliate interests of various communities involved in the process of marketization reform of the urban water supply industry so as to actualize the coordination of efficiency and fairness.At the end,an assumption on urban water price is put forward to help achieve the public water service equalization.
文摘Developing effective and practical electrocatalyst under industrial electrolysis conditions is critical for renewable hydrogen production.Herein,we report the self-supporting NiFe LDH-MoS_(x) integrated electrode for water oxidation under normal alkaline test condition(1 M KOH at 25℃)and simulated industrial electrolysis conditions(5 M KOH at 65℃).Such optimized electrode exhibits excellent oxygen evolution reaction(OER)performance with overpotential of 195 and 290 mV at current density of 100 and 400 mA·cm^(-2) under normal alkaline test condition.Notably,only over-potential of 156 and 201 mV were required to achieve the current density of 100 and 400mA·cm^(-2) under simulated industrial electrolysis conditions.No significant degradations were observed after long-term durability tests for both conditions.When using in two-electrode system,the operational voltages of 1.44 and 1.72 V were required to achieve a current density of 10 and 100 mA·cm^(-2) for the overall water splitting test(NiFe LDH-MoS_(x)/INF||20%Pt/C).Additionally,the operational voltage of employing NiFe LDH-MoS_(x)/INF as both cathode and anode merely require 1.52 V at 50mA·cm^(-2) at simulated industrial electrolysis conditions.Notably,a membrane electrode assembly(MEA)for anion exchange membrane water electrolysis(AEMWEs)using NiFe LDH-MoS_(x)/INF as an anode catalyst exhibited an energy conversion efficiency of 71.8%at current density of 400 mA·cm^(-2)in 1 M KOH at 60℃.Further experimental results reveal that sulfurized substrate not only improved the conductivity of NiFe LDH,but also regulated its electronic configurations and atomic composition,leading to the excellent activity.The easy-obtained and cost-effective integrated electrodes are expected to meet the large-scale application of industrial water electrolysis.
基金sponsored by China Scholarship Council (Grant No. LJC [2007]3020)Scholarship Fund granted by the Board of Directors of Igud Yotzei Sin in Israel and Israel-China Friendship Society
文摘Despite the endemic drought, arid climate and associated limited freshwater resources, as well as difficult geopolitical realities, Israel can provide a reliable supply of high quality water to a rapidly growing population. The achievements of water supply in Israel can be summarized as water technologies (like water transportation and purification, desalination, wastewater treatment, effluent reuse, storm water catchment, control systems, rain enhancement and drip irrigation, etc.), water management and legislation as well as water industry. In view of the national concern regarding the quality and quantity of the water, the skills, technologies and know-how that Israel has accumulated in water supply and irrigation can give us enlightenment that is also presented in this paper.
基金This research was funded by the National Natural Science Foundation of China(NSFC)[Grant Nos.51661015 and 52061024]the Natural Science Foundation of Zhejiang Province[Grant No.LQ20E010002].
文摘Amorphous alloy(MGs)is a solid alloy with disordered atomic accumulation obtained by ultra-rapid solidification of alloy melt.The atom deviates from the equilibrium position and is in metastable state.Up to now,a large number of MGs have been applied to the treatment of dye and heavy metal contaminated wastewater and ideal experimental results have been obtained.However,there is no literature to systematically summarize the chemical reaction and degradation mechanism in the process of degradation.On the basis of reviewing the classification,application,and synthesis of MGs,this paper introduces in detail the chemical reactions such as decolorization,mineralization,and ion leaching of Fe-based amorphous alloy(Fe-MGs)in the degradation of organic and inorganic salt wastewater through direct reduction or advanced oxidation mechanism.Compared with crystalline materials,the higher reaction rate of Fe-MGs can be attributed to lower activation energy,negative redox potential,loose product layer,and band structure with downward shift of valence band top.Finally,some suggestions and prospects are put forward for the limitations and research prospects of MGs in the environmental field,which provides a new idea for the synthesis of new environmental functional materials.
文摘The paper presents a flow plasma reactor permitting modification of the properties of water/aqueous solutions by stochastic resonance amplification of vibrations of selected chemical species in water with electromagnetic noise generated during a plasma discharge. The main parameters characterizing the quality for super-pure water, tap water and water from the intake in Besko (Poland) before and after the process in the plasma reactor were presented for comparison. In addition, the <sup>17</sup>O NMR (the full width at half maximum) and electrospray ionization mass spectrometry (ESI MS) methods were used to determine differences in physicochemical parameters between the untreated and plasma-treated water. It has been established that the water subjected to plasma treatment shows much different gas absorption properties than the untreated water samples, as a function of temperature and pressure, in this paper we report exemplary data for CO<sub>2</sub>, oxygen and acetylene. The improved gas absorption properties of the plasma-treated water make it attractive for the use in industrial processes. It is worth pointing to a great capacity of the new reactor (4000 l/h), and low energy consumption (20 MJ/h) for the treatment of the above mentioned volume flow rate of water.
基金supported by the Foundation of Basic and Applied Basic Research of Guangdong Province(2023B1515120043)the National Natural Science Foundation of China(22071069 and 22275060)+3 种基金the Yangfan Project of Maoming City(MMGCIRI2022YFJH-Y-014)Guangdong Basic and Applied Basic Research Foundation(2019A1515011512,2021A1515010172,and 2023A1515030274)the Foundation of the Smart Medical Innovation Technology Center in Guangdong University of Technology(ZYZX24-031)support from Analysis and Testing Center of Guangdong University of Technology。
文摘Metal–organic frameworks have garnered attention as highly efficient pre-electrocatalysts for the oxygen evolution reaction(OER).Current structure–activity relationships primarily rely on the assumption that the complete dissolution of organic ligands occurs during electrocatalysis.Herein,modeling based on NiFe Prussian blue analogs(NiFe-PBAs)show that cyanide ligands leach from the matrix and subsequently oxidize to corresponding inorganic ions(ammonium and carbonate)that re-adsorb onto the surface of NiFe OOH during the OER process.Interestingly,the surface-adsorbed inorganic ions induce the OER reaction of NiFe OOH to switch from the adsorbate evolution to the lattice-oxygen–mediated mechanism,thus contributing to the high activity.In addition,this reconstructed inorganic ion layer acting as a versatile protective layer can prevent the dissolution of metal sites to maintain contact between catalytic sites and reactive ions,thus breaking the activity–stability trade-off.Consequently,our constructed NiFePBAs exhibit excellent durability for 1250 h with an ultralow overpotential of 253 mV at 100 mA cm2.The scale-up NiFe-PBAs operated with a low energy consumption of4.18 kWh m3 H2 in industrial water electrolysis equipment.The economic analysis of the entire life cycle demonstrates that this green hydrogen production is priced at US$2.59 kg^(-1)H_(2),meeting global targets(<US$2.5 kg^(-1)H_(2)).
基金Item Sponsored by Preferred Scientific Research Foundation for Returned Overseas Chinese Scholars,Ministry of Human Resources and Social Security of China([2007]170)
文摘Electrosorption technology was used to treat the reused comprehensive wastewater from iron and steel industry. A problem of relatively high conductivity of wastewater which greatly affects the reuse was examined, and industrial test was conducted for the reused water advanced deionization and purification in a comprehensive wastewater treatment plant o{ WISCO [Wuhan Iron and Steel (Group) Corporation]. The results of the on-site in- dustrial test showed a satisfactory treatment performance for the reused water even at a flow rate of 1 000 L/h in a standard 500 L/h unit. The average conductivity decreased by about 70%, from 580--780 μS/cm to 100--350 μS/cm. The average removal efficiency of CI and Ca2+ was about 75% and 68%, respectively, and CODcr of the treated wa- ter was also reduced in some degree while the pH value was almost unchanged. The energy consumption was as low as 0.6 kWh/t, which was remarkably superior to the conventional technologies. Therefore, it is entirely feasible that the novel eleetrosorption technology can be used in enhanced desalination and purification treatment of reused com- prehensive wastewater in iron and steel industry.
文摘A full-scale plant using anaerobic, anoxic and oxic processes (A1/A2/O), along with a pilot-scale membrane bioreactor (MBR), nanofiltration (NF) and reverse osmosis (RO) integrated system developed by Shanghai Baosteel Chemical Co. Ltd., was investigated to treat coking wastewater for industrial reuse over a period of one year. The removals reached 82.5% (COD), 89.6% (BOD), 99.8% (ammonium nitrogen), 99.9% (phenol), 44.6% (total cyanide (T-CN)), 99.7% (thiocyanide (SCN-)) and 8.9% (fluoride), during the A1/A2/O biological treatment stage, and all parameters were further reduced by over 96.0%, except for fluoride (86.4%), in the final discharge effluent from the currently operating plant. The pilot-scale MBR process reduced the turbidity to less than 0.65 NTU, and most of the toxic organic compounds were degraded or intercepted by the A1/A2/O followed MBR processes. In addition, parameters including COD, T-CN, total nitrogen, fluoride, chloride ion, hardness and conductivity were significantly reduced by the NF-RO system to a level suitable for industrial reuse, with a total water production ratio of 70.7%. However, the concentrates from the NF and RO units were highly polluted and should be disposed of properly or further treated before being discharged.
文摘1.Introduction The current state of the wastewater industry is one of transition.In Europe,in the last 2 decades,we have seen a significant improvement on river water quality after implementation of the Urban Waste Water Treatment European Directive(91/271/EEC)[1],and the European Water Framework Directive[2].Up to 97% of the population have now access to safely managed wastewater treatment services.
基金National Key Project on Basic Research(973),No.2010CB951003The National Science and Technology Project,No.2014BAD10B06
文摘Water demand increases continuously with an increasing population and economic development. As a result, the difference between water supply and demand becomes a sig- nificant issue, especially in arid regions. To figure out the utilization of water resources in the arid region of northwestern China (ARNWC), and also to provide methodologies to predict the water use in future, three models were established in this study to calculate agricultural irri- gation, industrial and domestic water use in the ARNWC from the late 1980s to 2010. Based on river discharges in the region, the supply and demand of water resources at the river basin level were analyzed. The results indicated that agricultural irrigation demand occupies more than 90% of the total water use in the ARNWC. Total water demand increased from 31.97 km3 in the late 1980s to 48.19 km3 in 2010. Most river basins in this arid region were under me- dium and high water stress. Severe-risk river basins, such as the Shiyang river basin and the eastern part of the northern piedmont of the Tianshan Mountains, were found in this region. It was revealed that the water supply became critical from April to May, which was the season of the lowest water supply as determined by comparing monthly water consumption.
基金National Natural Science Foundation of China,No.41071057National Natural Science Foundation of China,No.41001388 Key Research Institute of Humanities and Social Sciences under the Ministry of Education,No.2009JJD770025
文摘The paper presents the prediction of total energy production and consumption in all provinces and autonomous regions as well as determination of the variation of gravity center of the energy production, consumption and total discharge of industrial waste water, gas and residue of China via the energy and environmental quality data from 1978 to 2009 in China by use of GM(1,1) model and gravity center model, based on which the paper also analyzes the dynamic variation in regional difference in energy production, consumption and environmental quality and their relationship. The results are shown as follows. 1) The gravity center of energy production is gradually moving southwestward and the entire movement track approxi-mates to linear variation, indicating that the difference of energy production between the east and west, south and north is narrowing to a certain extent, with the difference between the east and the west narrowing faster than that between the south and the north. 2) The gravity center of energy consumption is moving southwestward with perceptible fluctuation, of which the gravity center position from 2000 to 2005 was relatively stable, with slight annual position variation, indicating that the growth rates of all provinces and autonomous regions are basically the same. 3) The gravity center of the total discharge of industrial waste water, gas and residue is characterized by fluctuation in longitude and latitude to a certain degree. But, it shows a southwestward trend on the whole. 4) There are common ground and discrepancy in the variation track of the gravity center of the energy production consumption of China, and the comparative analysis of the gravity center of them and that of total discharge of industrial waste water, gas and residue shows that the environmental quality level is closely associated with the energy production and consumption (especially the energy consumption), indicating that the environment cost in economy of energy is higher in China.
文摘China's rapid economic growth poses serious concerns over environmental degradation, especially in the context of higher pollution levels resulting from unprecedented industrial activity. It is commonly held that government policies are effective in the form of investment in pollution control and the imposition of a discharge fee on industrial units for the purpose of safety of environmental quality. In this study, we find that government policies do not prove to be successful in controlling air pollution in comparison to water pollution. Furthermore, air pollution is increasing, while water pollution is following a stable, decreasing curve. Hence, some reforms need to be implemented in government policies, particularly those concerning the effectiveness of investment in environmental protection and improving managerial skills in industry.