With the continuous advancement of the country’s urbanization process,many cities are simultaneously carrying out the renovation of old urban areas while building new urban areas,which involves the demolition of many...With the continuous advancement of the country’s urbanization process,many cities are simultaneously carrying out the renovation of old urban areas while building new urban areas,which involves the demolition of many buildings and municipal infrastructures.To ensure the smooth progress of demolition projects,related safety management work is crucial.This article will discuss the safety management measures for demolition projects based on the basic principles of safety management for municipal infrastructure demolition projects,taking the demolition of gas storage tanks as an example.展开更多
Minocycline has been widely used in clinical treatment and its residues were considered to have environmental safety risks due to complex chemical structure.Therefore,it is necessary to find an efficient and environme...Minocycline has been widely used in clinical treatment and its residues were considered to have environmental safety risks due to complex chemical structure.Therefore,it is necessary to find an efficient and environmentally friendly method to remove minocycline from the environment.This study screened and isolated a minocycline degrading strain DM13 from the activated sludge for municipal sewage pipeline,and optimized the biodegradation of minocycline by DM13 under various environmental conditions.The maximum biodegradation efficiency of 50 mg/L minocycline reached 93%at 72 h with the temperature of 30℃,the initial pH of 7.0,and the inoculation rate of 3%.Two potential biotransformation pathways were proposed,including deamination,demethylation,and decarbonylation.The acute toxicity assessment showed that the biotransformation products of minocycline had lower toxicity than the parent compound.In addition,the first-generation tetracycline antibiotics could be removed,suggesting that strain DM13 has the potential for application in treating antibiotic wastewater.展开更多
As an energy and carbon saving process for nitrogen removal from wastewater,the partial nitrification and denitrification process(PN/D)has been extensively researched.However,achieving stable PNinmunicipalwastewater h...As an energy and carbon saving process for nitrogen removal from wastewater,the partial nitrification and denitrification process(PN/D)has been extensively researched.However,achieving stable PNinmunicipalwastewater has always been challenging.In this study,a gel immobilized PN/D nitrogen removal process(GI-PN/D)was established.A 94 days pilot-scale experiment was conducted using real municipal wastewater with an ammonia concentration of 43.5±5.3mg N/L at a temperature range of 11.3–28.7◦C.The nitrogen removal performance and associated pathways,shifts in the microbial community as well as sludge yield were investigated.The results were as follows:the effluent TN and COD were 0.6±0.4mg/L and 31.1±3.8 mg/L respectively,and the NAR exceeding 95%.GI-PN/D achieved deep nitrogen removal ofmunicipalwastewater through stable PN without taking any othermeasures.The primary pathways for nitrogen removal were identified as denitrification,simultaneous nitrification-denitrification,and aerobic denitrification.High-throughput sequencing analysis revealed that the immobilized fillers facilitated the autonomous enrichment of functional bacteria in each reactor,effectively promoting the dominance and stability of the microbial communities.In addition,GI-PN/D had the characteristic of low sludge yield,with an average sludge yield of 0.029 kg SS/kg COD.This study provides an effective technical for nitrogen removal from municipal wastewater through PN.展开更多
To perform a systematic survey on the occurrence and removal of micropollutants during municipal wastewater treatment, 943 semi-volatile organic chemicals in 32 wastewater samples including influents of secondary trea...To perform a systematic survey on the occurrence and removal of micropollutants during municipal wastewater treatment, 943 semi-volatile organic chemicals in 32 wastewater samples including influents of secondary treatments, secondary effluents and final effluents（effluents of advanced treatments）, which were collected from seven full-scale municipal wastewater treatment plants（MWTPs） in China, were examined by gas chromatography-mass spectrometry（GC-MS） coupled with an automated identification and quantification system with a database（AIQS-DB）. In total, 196 and 145 chemicals were detected in secondary and final effluents, respectively. The majority of the total concentrations（average removal efficiency, 87.0%±5.9%） of the micropollutants were removed during secondary treatments. However, advanced treatments achieved different micropollutant removal extents from secondary effluents depending on the different treatment processes employed. Highly variable removal efficiencies of total concentrations（32.7%–99.3%） were observed among the different advanced processes. Among them,ozonation-based processes could remove 70.0%–80.9% of the total concentrations of studied micropollutants. The potentially harmful micropollutants, based on their detection frequency and concentration in secondary and final effluents, were polycyclic aromatic hydrocarbons（PAHs）（2-methylnaphthalene, fluoranthene, pyrene, naphthalene and phenanthrene）, phosphorus flame retardants（tributyl phosphate（TBP）, tris（2-chloroethyl）phosphate（TCEP） and tris（1,3-dichloro-2-propyl） phosphate（TDCP））, phthalates（bis（2-ethylhexyl）phthalate（DEHP））, benzothiazoles（benzothiazole,2-（methylthio）-benzothiazol, and 2（3H）-benzothiazolone） and phenol. This study indicated that the presence of considerable amounts of micropollutants in secondary effluent creates the need for suitable advanced treatment before their reuse.展开更多
Static aerobic composting of municipal sewage sludge with forced ventilation or air ventilation using matured compost as bulking conditioner was investigated. Physical and chemical parame ,eters, e.g., temperature, mo...Static aerobic composting of municipal sewage sludge with forced ventilation or air ventilation using matured compost as bulking conditioner was investigated. Physical and chemical parame ,eters, e.g., temperature, moisture content, VSS, CODcr, pH, and germination index （GI）, were analyzed to characterize the composting process. Fermentation starts quickly in both forced and air ventilation compost heaps and reaches high-temperature stage after 2 d, owing to the bulking function of matured compost. Compared to air ventilation, however, forced ventilation enables the high-temperature stage to last longer for approximately 7 d. The moisture content of both compost bodies decreases from 62% to about 50% as a result of evaporation, and it decreases slightly faster in forced ventilation compost heap after 13 d due to the higher temperature and better ventilation condition. Although no obvious differences of VSS and pH are observed between both compost heaps, the soluble CODcr and GI show differences during the second half period of fermentation. In forced ventilation compost, the soluble CODcr has a small rebound after 13 d, and GI decreases from 46% to 35% but then increases. These results show that in general, the matured compost is a good conditioner and force ventilation with a proper air supply strategy can be more efficient than air ventilation.展开更多
This study provided insights into the persistent yellowish color in biological and tertiary effluents of municipal wastewater through a multi-characterization approach and fluorescence excitation-emission matrix-paral...This study provided insights into the persistent yellowish color in biological and tertiary effluents of municipal wastewater through a multi-characterization approach and fluorescence excitation-emission matrix-parallel factor(EEM-PARAFAC)analysis.The characterization was performed on three to five full-scale municipal wastewater treatment plants(WWTPs),including differential log-transformed absorbance(DLn A)spectroscopy,resin fractionation,size-exclusion chromatography for apparent molecular weight analysis(SECAMW),and X-ray photoelectron spectroscopy(XPS)analysis.Hydrophobic acids(HPOA)were abundant in visible colored dissolved organic matter(DOM).The SEC-AMW result showed that the molecular weight of the colored substances in the secondary effluents is mainly distributed in the range of 2–3 k Da.Through XPS analysis,C-O/C-N and pyrrolic/pyridonic(N-5)were found to be positively correlated with chroma.PARAFAC component models were built on biological(two components)and tertiary effluent(three components)and the correlation analysis revealed that PARAFAC component 2 in biological effluent(BE-C2)and component 1in tertiary effluent(TE-C1),which were ascribed to Hydrophobic acids and Humic acid-like,were the responsible visible colored DOM components cause yellowish color.In addition,component similarity testing found that the identified visible colored DOM PARAFAC BE-C2,and PARAFAC TE-C1 were identical(0.96)in physicochemical properties,with 4%removal efficacy on average,compared with 11%for invisible colored DOM.This implied that tertiary effluents containing colorants(TE-C1)were resistant to degradation/removal using different disinfection and filtration processes in advanced treatments.This sheds light on many physicochemical aspects of PARAFAC-identified visible colored DOM components and provides spectral data to build an online monitoring system.展开更多
In an era governed by economic crisis, deep recession and lack of funds, the perspective of sustainable development drives local government to a more focused and constant effort to adapt to their daily requirements no...In an era governed by economic crisis, deep recession and lack of funds, the perspective of sustainable development drives local government to a more focused and constant effort to adapt to their daily requirements not only in respect to the central state but also towards the growing needs of the local society. As the need for planning actions in accordance with the principles of sustainable energy remains urgent, municipalities continue to envision and to respond to their role in helping to create a better future for generations to come. Thereupon the vision of the Municipality of Hersonissos, as firstly recorded in its Business Plan for 2011-2014, was, and still is, its＇ development in an Economic, Tourist and Cultural pole by adopting and applying the basic principles of sustainable development. At the same time the Municipality＇s rigid vision, planning, and evaluation, oriented by environmental protection, highlighted the need for networking on European level as although cities are different, their problems are often common. Thus on April 18, 2011, the Municipality of Hersonissos, joined the European Union initiative ＂Covenant of Mayors＂ [1] with the common aim of the fight against climate change. This article presents the significant initiatives taken in this direction in the last decade and their results not only on economical level but also along their social impact. It also aims to point out a municipality＇s vital role in knowledge and technology diffusion within the local society as sustainable energy development can be deployed not only by the private sector but also by the public.展开更多
Ecological municipal solid waste (MSW) treatment systems are complex systems engineering concerning with multiple objectives and hierarchical levels. By combining an extension method with fuzzy logic theory, this pape...Ecological municipal solid waste (MSW) treatment systems are complex systems engineering concerning with multiple objectives and hierarchical levels. By combining an extension method with fuzzy logic theory, this paper investigated key technologies required by the comprehensive evaluation of ecological health. The method includes the construction of an evaluation system, quantification of evaluation indices, development of a matter-element model, development of an extension evaluation method, and assignment of a blended weight that combines subjectively and objectively estimated weights. This approach was used to develop a comprehensive model for evaluating the ecological health of an ecological treatment system for MSW. The model was then applied to a case study, and the results demonstrated that the model is a reasonable and effective.展开更多
To evaluate the removal efficiency of organic pollutants in the sewage by Harbin municipal sewage treatment plant, the influent and effluent samples from the plant were pretreated by liquid-liquid extraction （LLE） u...To evaluate the removal efficiency of organic pollutants in the sewage by Harbin municipal sewage treatment plant, the influent and effluent samples from the plant were pretreated by liquid-liquid extraction （LLE） under conditions of acidity, neutrality and alkaleseence in sequence, and then were analyzed by gas chromatograph-mass spectrum （GC-MS） procedures. Results indicate that there are 70 species of organic pollutants in the influent sample of the plant, which mainly consist of alkyls, benzene series, esters, and heteroeyclic compounds. Some of these organic pollutants are biotoxie and belong to persistent organic pollutants （POPs）. Four species among them are on the list of Prior Pollutants of Environmental Protection Agency of USA （USEPA）. However, 7 species of organic pollutants appearing in the effluent sample mainly include alkyls of multi-carbons and phthalate esters. The removal efficiency of phthalates is poor because of their poor biodegradability. The sewage treatment technique is effective in removing most＋of organics pollutants.展开更多
Based on the latest study of phosphate detergent ban and restrict, the phosphorus discharge from detergent in Beijing has been investigated. According to the status of wastewater treatment plants and its practical fun...Based on the latest study of phosphate detergent ban and restrict, the phosphorus discharge from detergent in Beijing has been investigated. According to the status of wastewater treatment plants and its practical function, phosphate-based detergent's contribution to the municipal sewage is calculated to be 8.41%, which is less than the average (20% ) in most other cities of China.展开更多
In order to achieve its objectives and to handle its real estate in a professional manner, the real estate company of the municipality of Groningen would like to begin managing the social real estate portfolio in an i...In order to achieve its objectives and to handle its real estate in a professional manner, the real estate company of the municipality of Groningen would like to begin managing the social real estate portfolio in an innovative way. The use of data and information technologies, or data-driven working and managing, provides insight into the effectiveness and efficiency of the portfolio. This roadmap includes, in addition to a theoretical framework, a step-by-step plan describing the process towards data-driven real estate management. The starting point here is to invent step by step, because data-driven real estate management requires a different way of thinking and doing. Actionable insights are created so that strategic management becomes possible. The data model to be developed forms the basis for entering into dialogue, taking decisions and drawing up long-term goals. The outcome is a data model for a proactive, agile, future-proof organization that is capable of responding to a changing environment and manages for the highest possible social return.展开更多
With the continuous reform and change of the construction market, EPC project general contracting and project management have gradually become the dominant mode in the construction market, and are widely used in real ...With the continuous reform and change of the construction market, EPC project general contracting and project management have gradually become the dominant mode in the construction market, and are widely used in real estate development and large-scale municipal infrastructure construction. Among them, the design-oriented EPC project general contracting has been vigorously promoted by the national policy due to its technical advantages and resource advantages. This paper analyzes the characteristics of the general contracting mode and design-led EPC municipal projects, the existing problems in cost management, and the cost control and management measures at each stage.展开更多
The 21st century is the era of information, small to our daily home, to scientific research, education and other fields, information technology has been fully integrated into our life, become our normal life can not l...The 21st century is the era of information, small to our daily home, to scientific research, education and other fields, information technology has been fully integrated into our life, become our normal life can not leave the technology. Municipal engineering construction is related to people's livelihood. Strengthening the quality and safety of engineering construction is conducive to ensuring people's interests. The application of BIM technology in engineering construction can provide powerful technical support to ensure a more stable operation of the project. This paper has carried out relevant research.展开更多
With the rapid development of society, there are more and more municipal engineering construction projects, which also put forward higher requirements for the speed of urban construction. The rapid development of citi...With the rapid development of society, there are more and more municipal engineering construction projects, which also put forward higher requirements for the speed of urban construction. The rapid development of cities will often produce many pollution problems. In order to improve this bad situation in our country, construction units are required to properly deal with factors that have adverse impact on the environment, such as dust, waste gas and wastewater. The construction party shall design a green construction plan with environmental protection as the major premise based on the actual conditions of the construction site and the surrounding environment, so as to effectively solve the pollution problems of various degrees. This paper will clarify the significance of environmental protection construction and its construction measures in order to contribute to the construction of a green city.展开更多
Under the EPC general contracting mode, the cross operation and three-dimensional operation of multi-specialties and types of work make it more difficult for all parties to coordinate. The EPC project has the characte...Under the EPC general contracting mode, the cross operation and three-dimensional operation of multi-specialties and types of work make it more difficult for all parties to coordinate. The EPC project has the characteristics of wide coverage, long construction period and many uncontrollable factors. Compared with the traditional general construction contract, the EPC project has higher requirements for the whole process cost control of the contractor. Municipal general contracting enterprises need to take corresponding cost control measures in bidding, design, procurement, construction, completion settlement and other stages, so as to minimize uncontrollable risks and strive for the maximum economic benefits of enterprises.展开更多
In recent years, urban waterlogging has occurred frequently, which has greatly affected and destroyed traffic safety, urban sanitation and urban ecosystem, and also caused serious economic losses. One of the main reas...In recent years, urban waterlogging has occurred frequently, which has greatly affected and destroyed traffic safety, urban sanitation and urban ecosystem, and also caused serious economic losses. One of the main reasons for urban waterlogging is the irrationality of urban drainage system. However, due to the strong concealment of municipal drainage pipeline engineering, it will be difficult to carry out timely maintenance if problems occur, and the quality problems in the construction process are easily concealed, leaving hidden dangers for later operation, thus bringing inconvenience to residents daily life. Therefore, it is particularly important to pay more attention to the construction of drainage pipes, strictly check and accept the construction of drainage pipes, and study the quality risk factors of municipal drainage pipes to prevent problems before they happen.展开更多
In the process of modern city construction and development, municipal engineering occupies an extremely important position, which affects the development of urbanization process. However, due to the large number of fi...In the process of modern city construction and development, municipal engineering occupies an extremely important position, which affects the development of urbanization process. However, due to the large number of fields involved in the construction process of municipal engineering, construction quality and potential risks are extremely easy to cause, which affects the smooth progress of the construction process. Therefore, the construction unit needs to strengthen the development of risk management, improve the supervision mechanism, and organize personnel to conduct real-time supervision and inspection of the construction process, to ensure the construction progress and quality, and to lay a solid foundation for the healthy and stable construction operation and development of municipal engineering.展开更多
In view of the municipal construction of bridge engineering plays an important role in social development, technical personnel must strengthen the study of construction technology, for the key technology involved in t...In view of the municipal construction of bridge engineering plays an important role in social development, technical personnel must strengthen the study of construction technology, for the key technology involved in the construction process, construction personnel should combine the actual construction link, the necessary improvement and innovation, promote the progress of bridge construction technology. At the same time, in the construction, the construction enterprise should carry out a reasonable management of the construction quality of the bridge. For example, to prevent steel corrosion, control uniform settlement, improve the construction of concrete pavement. In order to ensure the safety and service life of highway and bridge construction, it provides an effective guarantee.展开更多
Anaerobic ammonium oxidation（ANAMMOX） is a recently developed process to treat ammonia-rich wastewater. There were numerous articles about the new technology with focus on the ammonium-rich wastewater treatment, but...Anaerobic ammonium oxidation（ANAMMOX） is a recently developed process to treat ammonia-rich wastewater. There were numerous articles about the new technology with focus on the ammonium-rich wastewater treatment, but few on advanced municipal wastewater treatment. The paper studied the anaerobic ammonium oxidation （ANAMMOX） process with a down flow anoxic biofilter for nitrogen removal from secondary clarifier effluent of municipal wastewater with low COD/N ratio. The results showed that ANAMMOX process is applicable to advanced wastewater treatment with normal temperature as well as ammonia-rich high temperature wastewater treatment. The results indicated that ammonia removal rate was improved by raising the nitrite concentration, and the reaction rate reached a climax at 118.4 mgN/L of the nitrite nitrogen concentration. If the concentration exceeds 118.4 mgN/L, the ANAMMOX process was significantly inhibited although the ANAMMOX bacteria still showed a relatively high reactivity. The data also indicated that the ratio of NO2^- -N：NH4 ＊ -N = 1.3：1 in the influent was appropriate for excellent nitrogen removal. The pH increased gradually along the ANAMMOX biofilter reactor. When the ANAMMOX reaction was ended, the pH was tend to calm. The data suggested that the pH could be used as an indicator to describe the course of ANAMMOX reaction.展开更多
Jar tests were conducted to investigate the performance of enhanced primary treatment processes for low-concentra-tion municipal wastewater from South China by using composite flocculant combined with bio-flocculants ...Jar tests were conducted to investigate the performance of enhanced primary treatment processes for low-concentra-tion municipal wastewater from South China by using composite flocculant combined with bio-flocculants Pullulan and poly-aluminum-chloride (PAC). The optimum dosage for composite flocculant and conditions for flocculation were determined. The experimental results indicated that composite flocculant had high efficiency for removing over 95% of turbidity, over 58% of CODCr (chemical oxygen demand determined with potassium dichromate), over 91% of TP (total phosphate), and over 15% of NH3-N. Moreover, it could improve sludge settling and dehydration properties, and decrease the treatment cost.展开更多
文摘With the continuous advancement of the country’s urbanization process,many cities are simultaneously carrying out the renovation of old urban areas while building new urban areas,which involves the demolition of many buildings and municipal infrastructures.To ensure the smooth progress of demolition projects,related safety management work is crucial.This article will discuss the safety management measures for demolition projects based on the basic principles of safety management for municipal infrastructure demolition projects,taking the demolition of gas storage tanks as an example.
基金supported by the Natural Science Basic Research Program of Shaanxi Province(No.2023-JC-JQ-36).
文摘Minocycline has been widely used in clinical treatment and its residues were considered to have environmental safety risks due to complex chemical structure.Therefore,it is necessary to find an efficient and environmentally friendly method to remove minocycline from the environment.This study screened and isolated a minocycline degrading strain DM13 from the activated sludge for municipal sewage pipeline,and optimized the biodegradation of minocycline by DM13 under various environmental conditions.The maximum biodegradation efficiency of 50 mg/L minocycline reached 93%at 72 h with the temperature of 30℃,the initial pH of 7.0,and the inoculation rate of 3%.Two potential biotransformation pathways were proposed,including deamination,demethylation,and decarbonylation.The acute toxicity assessment showed that the biotransformation products of minocycline had lower toxicity than the parent compound.In addition,the first-generation tetracycline antibiotics could be removed,suggesting that strain DM13 has the potential for application in treating antibiotic wastewater.
基金supported by Beijing Municipal Commission of Education(No.Z161100004516015)the Open Project Program of Hebei Center for Ecological and Environmental Geology Research(No.JSYF-202304).
文摘As an energy and carbon saving process for nitrogen removal from wastewater,the partial nitrification and denitrification process(PN/D)has been extensively researched.However,achieving stable PNinmunicipalwastewater has always been challenging.In this study,a gel immobilized PN/D nitrogen removal process(GI-PN/D)was established.A 94 days pilot-scale experiment was conducted using real municipal wastewater with an ammonia concentration of 43.5±5.3mg N/L at a temperature range of 11.3–28.7◦C.The nitrogen removal performance and associated pathways,shifts in the microbial community as well as sludge yield were investigated.The results were as follows:the effluent TN and COD were 0.6±0.4mg/L and 31.1±3.8 mg/L respectively,and the NAR exceeding 95%.GI-PN/D achieved deep nitrogen removal ofmunicipalwastewater through stable PN without taking any othermeasures.The primary pathways for nitrogen removal were identified as denitrification,simultaneous nitrification-denitrification,and aerobic denitrification.High-throughput sequencing analysis revealed that the immobilized fillers facilitated the autonomous enrichment of functional bacteria in each reactor,effectively promoting the dominance and stability of the microbial communities.In addition,GI-PN/D had the characteristic of low sludge yield,with an average sludge yield of 0.029 kg SS/kg COD.This study provides an effective technical for nitrogen removal from municipal wastewater through PN.
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment in China(No.2017ZX07106005)
文摘To perform a systematic survey on the occurrence and removal of micropollutants during municipal wastewater treatment, 943 semi-volatile organic chemicals in 32 wastewater samples including influents of secondary treatments, secondary effluents and final effluents（effluents of advanced treatments）, which were collected from seven full-scale municipal wastewater treatment plants（MWTPs） in China, were examined by gas chromatography-mass spectrometry（GC-MS） coupled with an automated identification and quantification system with a database（AIQS-DB）. In total, 196 and 145 chemicals were detected in secondary and final effluents, respectively. The majority of the total concentrations（average removal efficiency, 87.0%±5.9%） of the micropollutants were removed during secondary treatments. However, advanced treatments achieved different micropollutant removal extents from secondary effluents depending on the different treatment processes employed. Highly variable removal efficiencies of total concentrations（32.7%–99.3%） were observed among the different advanced processes. Among them,ozonation-based processes could remove 70.0%–80.9% of the total concentrations of studied micropollutants. The potentially harmful micropollutants, based on their detection frequency and concentration in secondary and final effluents, were polycyclic aromatic hydrocarbons（PAHs）（2-methylnaphthalene, fluoranthene, pyrene, naphthalene and phenanthrene）, phosphorus flame retardants（tributyl phosphate（TBP）, tris（2-chloroethyl）phosphate（TCEP） and tris（1,3-dichloro-2-propyl） phosphate（TDCP））, phthalates（bis（2-ethylhexyl）phthalate（DEHP））, benzothiazoles（benzothiazole,2-（methylthio）-benzothiazol, and 2（3H）-benzothiazolone） and phenol. This study indicated that the presence of considerable amounts of micropollutants in secondary effluent creates the need for suitable advanced treatment before their reuse.
基金Projects(50978087,50908081)supported by the National Natural Science Foundation of China
文摘Static aerobic composting of municipal sewage sludge with forced ventilation or air ventilation using matured compost as bulking conditioner was investigated. Physical and chemical parame ,eters, e.g., temperature, moisture content, VSS, CODcr, pH, and germination index （GI）, were analyzed to characterize the composting process. Fermentation starts quickly in both forced and air ventilation compost heaps and reaches high-temperature stage after 2 d, owing to the bulking function of matured compost. Compared to air ventilation, however, forced ventilation enables the high-temperature stage to last longer for approximately 7 d. The moisture content of both compost bodies decreases from 62% to about 50% as a result of evaporation, and it decreases slightly faster in forced ventilation compost heap after 13 d due to the higher temperature and better ventilation condition. Although no obvious differences of VSS and pH are observed between both compost heaps, the soluble CODcr and GI show differences during the second half period of fermentation. In forced ventilation compost, the soluble CODcr has a small rebound after 13 d, and GI decreases from 46% to 35% but then increases. These results show that in general, the matured compost is a good conditioner and force ventilation with a proper air supply strategy can be more efficient than air ventilation.
基金Financial support for this study was obtained from the Major Science and Technology Program for Water Pollution Control and Treatment(No.2017ZX07106005)financially supported by the CAS-TWAS president’s Fellowship for International Ph.D.Students(CAS-TWAS Fellowship No.2017A8004208001)。
文摘This study provided insights into the persistent yellowish color in biological and tertiary effluents of municipal wastewater through a multi-characterization approach and fluorescence excitation-emission matrix-parallel factor(EEM-PARAFAC)analysis.The characterization was performed on three to five full-scale municipal wastewater treatment plants(WWTPs),including differential log-transformed absorbance(DLn A)spectroscopy,resin fractionation,size-exclusion chromatography for apparent molecular weight analysis(SECAMW),and X-ray photoelectron spectroscopy(XPS)analysis.Hydrophobic acids(HPOA)were abundant in visible colored dissolved organic matter(DOM).The SEC-AMW result showed that the molecular weight of the colored substances in the secondary effluents is mainly distributed in the range of 2–3 k Da.Through XPS analysis,C-O/C-N and pyrrolic/pyridonic(N-5)were found to be positively correlated with chroma.PARAFAC component models were built on biological(two components)and tertiary effluent(three components)and the correlation analysis revealed that PARAFAC component 2 in biological effluent(BE-C2)and component 1in tertiary effluent(TE-C1),which were ascribed to Hydrophobic acids and Humic acid-like,were the responsible visible colored DOM components cause yellowish color.In addition,component similarity testing found that the identified visible colored DOM PARAFAC BE-C2,and PARAFAC TE-C1 were identical(0.96)in physicochemical properties,with 4%removal efficacy on average,compared with 11%for invisible colored DOM.This implied that tertiary effluents containing colorants(TE-C1)were resistant to degradation/removal using different disinfection and filtration processes in advanced treatments.This sheds light on many physicochemical aspects of PARAFAC-identified visible colored DOM components and provides spectral data to build an online monitoring system.
文摘In an era governed by economic crisis, deep recession and lack of funds, the perspective of sustainable development drives local government to a more focused and constant effort to adapt to their daily requirements not only in respect to the central state but also towards the growing needs of the local society. As the need for planning actions in accordance with the principles of sustainable energy remains urgent, municipalities continue to envision and to respond to their role in helping to create a better future for generations to come. Thereupon the vision of the Municipality of Hersonissos, as firstly recorded in its Business Plan for 2011-2014, was, and still is, its＇ development in an Economic, Tourist and Cultural pole by adopting and applying the basic principles of sustainable development. At the same time the Municipality＇s rigid vision, planning, and evaluation, oriented by environmental protection, highlighted the need for networking on European level as although cities are different, their problems are often common. Thus on April 18, 2011, the Municipality of Hersonissos, joined the European Union initiative ＂Covenant of Mayors＂ [1] with the common aim of the fight against climate change. This article presents the significant initiatives taken in this direction in the last decade and their results not only on economical level but also along their social impact. It also aims to point out a municipality＇s vital role in knowledge and technology diffusion within the local society as sustainable energy development can be deployed not only by the private sector but also by the public.
文摘Ecological municipal solid waste (MSW) treatment systems are complex systems engineering concerning with multiple objectives and hierarchical levels. By combining an extension method with fuzzy logic theory, this paper investigated key technologies required by the comprehensive evaluation of ecological health. The method includes the construction of an evaluation system, quantification of evaluation indices, development of a matter-element model, development of an extension evaluation method, and assignment of a blended weight that combines subjectively and objectively estimated weights. This approach was used to develop a comprehensive model for evaluating the ecological health of an ecological treatment system for MSW. The model was then applied to a case study, and the results demonstrated that the model is a reasonable and effective.
文摘To evaluate the removal efficiency of organic pollutants in the sewage by Harbin municipal sewage treatment plant, the influent and effluent samples from the plant were pretreated by liquid-liquid extraction （LLE） under conditions of acidity, neutrality and alkaleseence in sequence, and then were analyzed by gas chromatograph-mass spectrum （GC-MS） procedures. Results indicate that there are 70 species of organic pollutants in the influent sample of the plant, which mainly consist of alkyls, benzene series, esters, and heteroeyclic compounds. Some of these organic pollutants are biotoxie and belong to persistent organic pollutants （POPs）. Four species among them are on the list of Prior Pollutants of Environmental Protection Agency of USA （USEPA）. However, 7 species of organic pollutants appearing in the effluent sample mainly include alkyls of multi-carbons and phthalate esters. The removal efficiency of phthalates is poor because of their poor biodegradability. The sewage treatment technique is effective in removing most＋of organics pollutants.
文摘Based on the latest study of phosphate detergent ban and restrict, the phosphorus discharge from detergent in Beijing has been investigated. According to the status of wastewater treatment plants and its practical function, phosphate-based detergent's contribution to the municipal sewage is calculated to be 8.41%, which is less than the average (20% ) in most other cities of China.
文摘In order to achieve its objectives and to handle its real estate in a professional manner, the real estate company of the municipality of Groningen would like to begin managing the social real estate portfolio in an innovative way. The use of data and information technologies, or data-driven working and managing, provides insight into the effectiveness and efficiency of the portfolio. This roadmap includes, in addition to a theoretical framework, a step-by-step plan describing the process towards data-driven real estate management. The starting point here is to invent step by step, because data-driven real estate management requires a different way of thinking and doing. Actionable insights are created so that strategic management becomes possible. The data model to be developed forms the basis for entering into dialogue, taking decisions and drawing up long-term goals. The outcome is a data model for a proactive, agile, future-proof organization that is capable of responding to a changing environment and manages for the highest possible social return.
文摘With the continuous reform and change of the construction market, EPC project general contracting and project management have gradually become the dominant mode in the construction market, and are widely used in real estate development and large-scale municipal infrastructure construction. Among them, the design-oriented EPC project general contracting has been vigorously promoted by the national policy due to its technical advantages and resource advantages. This paper analyzes the characteristics of the general contracting mode and design-led EPC municipal projects, the existing problems in cost management, and the cost control and management measures at each stage.
文摘The 21st century is the era of information, small to our daily home, to scientific research, education and other fields, information technology has been fully integrated into our life, become our normal life can not leave the technology. Municipal engineering construction is related to people's livelihood. Strengthening the quality and safety of engineering construction is conducive to ensuring people's interests. The application of BIM technology in engineering construction can provide powerful technical support to ensure a more stable operation of the project. This paper has carried out relevant research.
文摘With the rapid development of society, there are more and more municipal engineering construction projects, which also put forward higher requirements for the speed of urban construction. The rapid development of cities will often produce many pollution problems. In order to improve this bad situation in our country, construction units are required to properly deal with factors that have adverse impact on the environment, such as dust, waste gas and wastewater. The construction party shall design a green construction plan with environmental protection as the major premise based on the actual conditions of the construction site and the surrounding environment, so as to effectively solve the pollution problems of various degrees. This paper will clarify the significance of environmental protection construction and its construction measures in order to contribute to the construction of a green city.
文摘Under the EPC general contracting mode, the cross operation and three-dimensional operation of multi-specialties and types of work make it more difficult for all parties to coordinate. The EPC project has the characteristics of wide coverage, long construction period and many uncontrollable factors. Compared with the traditional general construction contract, the EPC project has higher requirements for the whole process cost control of the contractor. Municipal general contracting enterprises need to take corresponding cost control measures in bidding, design, procurement, construction, completion settlement and other stages, so as to minimize uncontrollable risks and strive for the maximum economic benefits of enterprises.
文摘In recent years, urban waterlogging has occurred frequently, which has greatly affected and destroyed traffic safety, urban sanitation and urban ecosystem, and also caused serious economic losses. One of the main reasons for urban waterlogging is the irrationality of urban drainage system. However, due to the strong concealment of municipal drainage pipeline engineering, it will be difficult to carry out timely maintenance if problems occur, and the quality problems in the construction process are easily concealed, leaving hidden dangers for later operation, thus bringing inconvenience to residents daily life. Therefore, it is particularly important to pay more attention to the construction of drainage pipes, strictly check and accept the construction of drainage pipes, and study the quality risk factors of municipal drainage pipes to prevent problems before they happen.
文摘In the process of modern city construction and development, municipal engineering occupies an extremely important position, which affects the development of urbanization process. However, due to the large number of fields involved in the construction process of municipal engineering, construction quality and potential risks are extremely easy to cause, which affects the smooth progress of the construction process. Therefore, the construction unit needs to strengthen the development of risk management, improve the supervision mechanism, and organize personnel to conduct real-time supervision and inspection of the construction process, to ensure the construction progress and quality, and to lay a solid foundation for the healthy and stable construction operation and development of municipal engineering.
文摘In view of the municipal construction of bridge engineering plays an important role in social development, technical personnel must strengthen the study of construction technology, for the key technology involved in the construction process, construction personnel should combine the actual construction link, the necessary improvement and innovation, promote the progress of bridge construction technology. At the same time, in the construction, the construction enterprise should carry out a reasonable management of the construction quality of the bridge. For example, to prevent steel corrosion, control uniform settlement, improve the construction of concrete pavement. In order to ensure the safety and service life of highway and bridge construction, it provides an effective guarantee.
文摘Anaerobic ammonium oxidation（ANAMMOX） is a recently developed process to treat ammonia-rich wastewater. There were numerous articles about the new technology with focus on the ammonium-rich wastewater treatment, but few on advanced municipal wastewater treatment. The paper studied the anaerobic ammonium oxidation （ANAMMOX） process with a down flow anoxic biofilter for nitrogen removal from secondary clarifier effluent of municipal wastewater with low COD/N ratio. The results showed that ANAMMOX process is applicable to advanced wastewater treatment with normal temperature as well as ammonia-rich high temperature wastewater treatment. The results indicated that ammonia removal rate was improved by raising the nitrite concentration, and the reaction rate reached a climax at 118.4 mgN/L of the nitrite nitrogen concentration. If the concentration exceeds 118.4 mgN/L, the ANAMMOX process was significantly inhibited although the ANAMMOX bacteria still showed a relatively high reactivity. The data also indicated that the ratio of NO2^- -N：NH4 ＊ -N = 1.3：1 in the influent was appropriate for excellent nitrogen removal. The pH increased gradually along the ANAMMOX biofilter reactor. When the ANAMMOX reaction was ended, the pH was tend to calm. The data suggested that the pH could be used as an indicator to describe the course of ANAMMOX reaction.
基金Project (No. 2005AA601010) supported by the Hi-Tech Research and Development Program (863) of China
文摘Jar tests were conducted to investigate the performance of enhanced primary treatment processes for low-concentra-tion municipal wastewater from South China by using composite flocculant combined with bio-flocculants Pullulan and poly-aluminum-chloride (PAC). The optimum dosage for composite flocculant and conditions for flocculation were determined. The experimental results indicated that composite flocculant had high efficiency for removing over 95% of turbidity, over 58% of CODCr (chemical oxygen demand determined with potassium dichromate), over 91% of TP (total phosphate), and over 15% of NH3-N. Moreover, it could improve sludge settling and dehydration properties, and decrease the treatment cost.
