Global water security is a severe issue that threatens human health and well-being. Finding sustainable alternative water resources has become a matter of great urgency. For coastal urban areas, desalinated seawater c...Global water security is a severe issue that threatens human health and well-being. Finding sustainable alternative water resources has become a matter of great urgency. For coastal urban areas, desalinated seawater could serve as a freshwater supply. However, since 20%-30% of the water supply is used for flushing waste from the city, seawater with simple treatment could also partly replace the use of freshwater. In this work, the freshwater saving potential and environmental impacts of the urban water system （water-wastewater closed loop） adopting seawater desalination, seawater for toilet flushing （SWTF）, or reclaimed water for toilet flushing （RWTF） are compared with those of a conventional freshwater system, through a life-cycle assessment and sensitivity analysis. The potential applications of these processes are also assessed. The results support the environmental sustainability of the SWTF approach, but its potential application depends on the coastal distance and effective population density of a city. Developed coastal cities with an effective population density exceeding 3000 persons.km-2 and located less than 30 km from the seashore （for the main pipe supplying seawater to the city） would benefit from applying SWTF, regardless of other impact parameters. By further applying the sulfate reduction, autotrophic denitrification, and nitrification integrated （SANI） process for wastewater treatment, the maximum distance from the seashore can be extended to 60 km. Considering that most modern urbanized cities fulfill these criteria, the next generation of water supply systems could consist of a freshwater supply coupled with a seawater supply for sustainable urban development.展开更多
The large concentration of human population,industry and services in the Metropolitan Area of Barcelona has to confront scarce water resources,serious seasonal and inter-annual variations and quality deficiencies in t...The large concentration of human population,industry and services in the Metropolitan Area of Barcelona has to confront scarce water resources,serious seasonal and inter-annual variations and quality deficiencies in the sources.A large fraction of these water resources are in the medium-size Llobregat River basin and the remaining ones correspond to a surface water transfer,seawater desalination and wastewater reclamation.Groundwater dominated water resources availability before 1950.Afterwards,water supply has evolved progressively to integrated water resources management,which includes serious water quality concerns to deal with population density,river pollution,seawater intrusion in the main aquifer,and brine generation in the mid Llobregat basin due to old mining of saline minerals.The role of the alluvial aquifers has progressively evolved from being the main water source to reserve storage to cope with seasonal and drought water resources availability.River-enhanced recharge and artificial recharge are needed to assure enough groundwater storage before surface water becomes scarce and/or suffers a serious temporal loss of quality.Enhanced river recharge started in 1950.Treated river water injection in dual-purpose wells was put into operation in the early 1970s.Basin and pond recharge was added later,as well as a deep well injection barrier along the coast to reduce seawater intrusion and to allow increased groundwater abstraction in moments of water scarcity.There is a progressive evolution from solving water quantity problems to consideration of water quality improvement during recharge,with attention to emergent concern pollutants in river water and in reclaimed water to be considered for artificial recharge.Improvement of artificial recharge operation activities has been introduced and research is being carried out on the difficult behavior to degrade organic pollutants during infiltration and in the terrain.This paper presents the different activities carried out and presents the research activities,and comments on the economic,social and administrative issues involved as well.展开更多
In the management of hydrology and water resources, hydrology prediction is an indispensable part. Scientific and rational application of relevant hydrological forecasting technology can improve the scientificity and ...In the management of hydrology and water resources, hydrology prediction is an indispensable part. Scientific and rational application of relevant hydrological forecasting technology can improve the scientificity and timeliness of its application. Based on the current situation of hydrology and water resources in a city, this paper emphatically discusses the practical application of hydrological prediction technology, points out that the basic principles of hydrology and water resources management should be followed in the management of hydrology and water resources, and proposes that the application of geographic information system should be continuously strengthened, and wireless sensor network should be established to enhance the reliability of data transmission. At the same time, it is necessary to strengthen hydrological and water resources prediction and management, strengthen the application of hydrological prediction technology, and establish a unified hydrological and water resources management platform. In order to promote regional economic development, it is also necessary to continuously optimize the management of regional water resources.展开更多
Most probable number （MPN） and colony-forming unit （CFU） estimates of fecal indicator bacteria （FIB） concentration are common measures of water quality in aquatic environments. Thus, FIB intensively monitored in...Most probable number （MPN） and colony-forming unit （CFU） estimates of fecal indicator bacteria （FIB） concentration are common measures of water quality in aquatic environments. Thus, FIB intensively monitored in Yeongsan Watershed in an attempt to compare two different methods and to develop a statistical model to convert from CFU to MPN estimates or vice versa. As a result, the significant difference was found in the MPN and CFU estimates. The enumerated Escherichia coli concentrations in MPN are greater than those in CFU, except for the measurement in winter. Especially in fall, E. coli concentrations in MPN are one order of magnitude greater than that in CFU. Contrarily, enterococci bacteria in MPN are lower than those in CFU. However, in general, a strongly positive relationship are found between MPN and CFU estimates. Therefore, the statistical models were developed, and showed the reasonable converting FIB concentrations from CFU estimates to MPN estimates. We expect this study will provide preliminary information towards future research on whether different analysis methods may result in different water quality standard violation frequencies for the same water sample.展开更多
Treating protein-rich wastewater using cost-effective and simple-structured single-stage reactors presents several challenges.In this study,we applied an anaerobic sequencing batch reactor(AnSBR)to treat protein-rich ...Treating protein-rich wastewater using cost-effective and simple-structured single-stage reactors presents several challenges.In this study,we applied an anaerobic sequencing batch reactor(AnSBR)to treat protein-rich wastewater from a slaughterhouse.We focused on identifying the key factors influencing the removal of chemical oxygen demand(COD)and the settling performance of the sludge.The AnSBR achieved a maximum total COD removal of 90%,a protein degradation efficiency exceeding 80%,and a COD to methane conversion efficiency of over 70%at organic loading rates of up to 6.2 g COD L^(-1)d^(-1).We found that the variations in both the organic loading rate within the reactor and the hydraulic retention time in the buffer tank had a significant effect on COD removal.The hydraulic retention time in the buffer tank and the reactor,which determined the ammonification efficiencies and the residual carbohydrate concentrations in the reactor liquid,affected the sludge settleability.Furthermore,the genus Clostridium sensu stricto 1,known as protein-and lipids-degraders,was predominant in the reactor.Statistical analysis showed a significant correlation between the core microbiome and ammonification efficiency,highlighting the importance of protein degradation as the governing process in the treatment.Our results will provide valuable insights to optimise the design and operation of AnSBR for efficient treatment of protein-rich wastewater.展开更多
Sewage sludge is a potential precursor for biochar production,but its effective utilization involves costly activation steps.To modify biochar properties while ensuring cost-effectiveness,we examined the feasibility o...Sewage sludge is a potential precursor for biochar production,but its effective utilization involves costly activation steps.To modify biochar properties while ensuring cost-effectiveness,we examined the feasibility of using seawater as an agent to activate biochar produced from sewage sludge.In our proof-of-concept study,seawater was proven to be an effective activation agent for biochar production,achieving a surface area of 480.3 m^(2)/g with hierarchical porosity distribution.Benefited from our design,the catalytic effect of seawater increased not only the surface area but also the graphitization degree of biochar when comparing the pyrolysis of sewage sludge without seawater.This leads to seawater activated biochar electrodes with lower resistance,higher capacitance of 113.9 F/g comparing with control groups without seawater.Leveraging the global increase in the salinity of groundwater,especially in coastal areas,these findings provide an opportunity for recovering a valuable carbon resource from sludge.展开更多
To efficiently remove organic and inorganic pollutants from leachate concentrate,an in situ coagulation-electrochemical oxidation(CO-EO)system was proposed using Ti/Ti_(4)O_(7)anode and Al cathode,coupling the“super-...To efficiently remove organic and inorganic pollutants from leachate concentrate,an in situ coagulation-electrochemical oxidation(CO-EO)system was proposed using Ti/Ti_(4)O_(7)anode and Al cathode,coupling the“super-Faradaic”dissolution of Al.The system was evaluated in terms of the removal efficiencies of organics,nutrients,and metals,and the underlying cathodic mechanisms were investigated compared with the Ti/RuO_(2)-IrO_(2)and graphite cathode systems.After a 3-h treatment,the Al-cathode system removed 89.0%of COD and 36.3%of total nitrogen(TN).The TN removal was primarily ascribed to the oxidation of both ammonia and organic-N to N_(2).In comparison,the Al-cathode system achieved 3-10-fold total phosphorus(TP)(62.6%)and metal removals(>80%)than Ti/RuO_(2)-IrO_(2)and graphite systems.The increased removals of TP and metals were ascribed to the in situ coagulation of Al(OH)_(3),hydroxide precipitation,and electrodeposition.With the reduced scaling on the Al cathode surface,the formation of Al^(3+)and electrified Al(OH)_(3)lessened the requirement for cathode cleaning and increased the bulk conductivity,resulting in increased instantaneous current production(38.9%)and operating cost efficiencies(48.3 kWh kg_(COD)^(−1)).The present study indicated that the in situ CO-EO process could be potentially used for treating persistent wastewater containing high levels of organic and inorganic ions.展开更多
文摘Global water security is a severe issue that threatens human health and well-being. Finding sustainable alternative water resources has become a matter of great urgency. For coastal urban areas, desalinated seawater could serve as a freshwater supply. However, since 20%-30% of the water supply is used for flushing waste from the city, seawater with simple treatment could also partly replace the use of freshwater. In this work, the freshwater saving potential and environmental impacts of the urban water system （water-wastewater closed loop） adopting seawater desalination, seawater for toilet flushing （SWTF）, or reclaimed water for toilet flushing （RWTF） are compared with those of a conventional freshwater system, through a life-cycle assessment and sensitivity analysis. The potential applications of these processes are also assessed. The results support the environmental sustainability of the SWTF approach, but its potential application depends on the coastal distance and effective population density of a city. Developed coastal cities with an effective population density exceeding 3000 persons.km-2 and located less than 30 km from the seashore （for the main pipe supplying seawater to the city） would benefit from applying SWTF, regardless of other impact parameters. By further applying the sulfate reduction, autotrophic denitrification, and nitrification integrated （SANI） process for wastewater treatment, the maximum distance from the seashore can be extended to 60 km. Considering that most modern urbanized cities fulfill these criteria, the next generation of water supply systems could consist of a freshwater supply coupled with a seawater supply for sustainable urban development.
文摘The large concentration of human population,industry and services in the Metropolitan Area of Barcelona has to confront scarce water resources,serious seasonal and inter-annual variations and quality deficiencies in the sources.A large fraction of these water resources are in the medium-size Llobregat River basin and the remaining ones correspond to a surface water transfer,seawater desalination and wastewater reclamation.Groundwater dominated water resources availability before 1950.Afterwards,water supply has evolved progressively to integrated water resources management,which includes serious water quality concerns to deal with population density,river pollution,seawater intrusion in the main aquifer,and brine generation in the mid Llobregat basin due to old mining of saline minerals.The role of the alluvial aquifers has progressively evolved from being the main water source to reserve storage to cope with seasonal and drought water resources availability.River-enhanced recharge and artificial recharge are needed to assure enough groundwater storage before surface water becomes scarce and/or suffers a serious temporal loss of quality.Enhanced river recharge started in 1950.Treated river water injection in dual-purpose wells was put into operation in the early 1970s.Basin and pond recharge was added later,as well as a deep well injection barrier along the coast to reduce seawater intrusion and to allow increased groundwater abstraction in moments of water scarcity.There is a progressive evolution from solving water quantity problems to consideration of water quality improvement during recharge,with attention to emergent concern pollutants in river water and in reclaimed water to be considered for artificial recharge.Improvement of artificial recharge operation activities has been introduced and research is being carried out on the difficult behavior to degrade organic pollutants during infiltration and in the terrain.This paper presents the different activities carried out and presents the research activities,and comments on the economic,social and administrative issues involved as well.
文摘In the management of hydrology and water resources, hydrology prediction is an indispensable part. Scientific and rational application of relevant hydrological forecasting technology can improve the scientificity and timeliness of its application. Based on the current situation of hydrology and water resources in a city, this paper emphatically discusses the practical application of hydrological prediction technology, points out that the basic principles of hydrology and water resources management should be followed in the management of hydrology and water resources, and proposes that the application of geographic information system should be continuously strengthened, and wireless sensor network should be established to enhance the reliability of data transmission. At the same time, it is necessary to strengthen hydrological and water resources prediction and management, strengthen the application of hydrological prediction technology, and establish a unified hydrological and water resources management platform. In order to promote regional economic development, it is also necessary to continuously optimize the management of regional water resources.
基金supported by the Korean Ministry of Environment as "The Eco-technopia 21 Project" (No. 019-071-053)
文摘Most probable number （MPN） and colony-forming unit （CFU） estimates of fecal indicator bacteria （FIB） concentration are common measures of water quality in aquatic environments. Thus, FIB intensively monitored in Yeongsan Watershed in an attempt to compare two different methods and to develop a statistical model to convert from CFU to MPN estimates or vice versa. As a result, the significant difference was found in the MPN and CFU estimates. The enumerated Escherichia coli concentrations in MPN are greater than those in CFU, except for the measurement in winter. Especially in fall, E. coli concentrations in MPN are one order of magnitude greater than that in CFU. Contrarily, enterococci bacteria in MPN are lower than those in CFU. However, in general, a strongly positive relationship are found between MPN and CFU estimates. Therefore, the statistical models were developed, and showed the reasonable converting FIB concentrations from CFU estimates to MPN estimates. We expect this study will provide preliminary information towards future research on whether different analysis methods may result in different water quality standard violation frequencies for the same water sample.
基金supported by Biothane Veolia Water Technologies Techno Center,KWR Water Research Institute and Hydrobusiness B.V as part of the TKI Project Innovative Slaughterhouse Wastewater Treatment TechnologyThis research was co-financed with PPS-funding from the Top consortia for Knowledge&Innovation(TKI’s)of the Dutch Ministry of Economic Affairs and Climate PolicyThe authors would like to thank China Scholarship Council for the State Scholarship Fund(No.201708450043)granted to the first author.
文摘Treating protein-rich wastewater using cost-effective and simple-structured single-stage reactors presents several challenges.In this study,we applied an anaerobic sequencing batch reactor(AnSBR)to treat protein-rich wastewater from a slaughterhouse.We focused on identifying the key factors influencing the removal of chemical oxygen demand(COD)and the settling performance of the sludge.The AnSBR achieved a maximum total COD removal of 90%,a protein degradation efficiency exceeding 80%,and a COD to methane conversion efficiency of over 70%at organic loading rates of up to 6.2 g COD L^(-1)d^(-1).We found that the variations in both the organic loading rate within the reactor and the hydraulic retention time in the buffer tank had a significant effect on COD removal.The hydraulic retention time in the buffer tank and the reactor,which determined the ammonification efficiencies and the residual carbohydrate concentrations in the reactor liquid,affected the sludge settleability.Furthermore,the genus Clostridium sensu stricto 1,known as protein-and lipids-degraders,was predominant in the reactor.Statistical analysis showed a significant correlation between the core microbiome and ammonification efficiency,highlighting the importance of protein degradation as the governing process in the treatment.Our results will provide valuable insights to optimise the design and operation of AnSBR for efficient treatment of protein-rich wastewater.
基金This research was supported by the National Natural Science Foundation of China(Grant No.51778165)Key Program of National Natural Science of China(Grant No.51638005)+2 种基金Science and Technology Development Fund,Macao Special Administrative Region,China(File No.FDCT-0104/2018/A3,FDCT-0057/2019/A1)Start-up Research Grant of University of Macao(Grant No.SRG2018-00110-FST)the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.[T21-604/19-R]).
文摘Sewage sludge is a potential precursor for biochar production,but its effective utilization involves costly activation steps.To modify biochar properties while ensuring cost-effectiveness,we examined the feasibility of using seawater as an agent to activate biochar produced from sewage sludge.In our proof-of-concept study,seawater was proven to be an effective activation agent for biochar production,achieving a surface area of 480.3 m^(2)/g with hierarchical porosity distribution.Benefited from our design,the catalytic effect of seawater increased not only the surface area but also the graphitization degree of biochar when comparing the pyrolysis of sewage sludge without seawater.This leads to seawater activated biochar electrodes with lower resistance,higher capacitance of 113.9 F/g comparing with control groups without seawater.Leveraging the global increase in the salinity of groundwater,especially in coastal areas,these findings provide an opportunity for recovering a valuable carbon resource from sludge.
基金This research was supported by the Science and Technology Development Fund of Macao(No.0002/2019/AGJ&0104/2018/A3)the Research Committee of the University of Macao Project(No.MYRG2019-00045-FST&MYRG2020-00148-FST).
文摘To efficiently remove organic and inorganic pollutants from leachate concentrate,an in situ coagulation-electrochemical oxidation(CO-EO)system was proposed using Ti/Ti_(4)O_(7)anode and Al cathode,coupling the“super-Faradaic”dissolution of Al.The system was evaluated in terms of the removal efficiencies of organics,nutrients,and metals,and the underlying cathodic mechanisms were investigated compared with the Ti/RuO_(2)-IrO_(2)and graphite cathode systems.After a 3-h treatment,the Al-cathode system removed 89.0%of COD and 36.3%of total nitrogen(TN).The TN removal was primarily ascribed to the oxidation of both ammonia and organic-N to N_(2).In comparison,the Al-cathode system achieved 3-10-fold total phosphorus(TP)(62.6%)and metal removals(>80%)than Ti/RuO_(2)-IrO_(2)and graphite systems.The increased removals of TP and metals were ascribed to the in situ coagulation of Al(OH)_(3),hydroxide precipitation,and electrodeposition.With the reduced scaling on the Al cathode surface,the formation of Al^(3+)and electrified Al(OH)_(3)lessened the requirement for cathode cleaning and increased the bulk conductivity,resulting in increased instantaneous current production(38.9%)and operating cost efficiencies(48.3 kWh kg_(COD)^(−1)).The present study indicated that the in situ CO-EO process could be potentially used for treating persistent wastewater containing high levels of organic and inorganic ions.
