The capability of Chlorella vulgaris to remove nitrogen in the form of ammonia and/or ammonium ions from wastewater effluent in a local wastewater treatment plant (i.e., the Mill Creek Plant in Cincinnati, Ohio, U.S...The capability of Chlorella vulgaris to remove nitrogen in the form of ammonia and/or ammonium ions from wastewater effluent in a local wastewater treatment plant (i.e., the Mill Creek Plant in Cincinnati, Ohio, U.S.A.) was studied. The wastewater effluent leaving the plant was found to include high concentra- tions of nitrogen (7.7±0.19 mg/L) (ammonia (NH3) and/or ammonium ion (NH4+)) and total inorganic carbon (58.6±0.28 mg/L) at pH 7, and to be suitable for growing Chlorella vulgaris. When Chlorella vulgaris was cul- tivated in a batch mode under a closed system, half of the nitrogen concentration was dramatically removed in 48 h after a 24-h lag-phase period. Total inorganic carbon concentration also concomitantly decreased during the rapid growth-phase. The total biomass weight gained during the entire cultivation period balanced out well with the total amount of inorganic carbon and nitrogen removed from the culture medium. These results indicate that wastewater can be synergistically used to polish residual nutrients in wastewater as well as to cultivate microalgae for biofuel production.展开更多
To solve the water shortage problem, an artificial groundwater recharge system will be constructed in Beijing for wastewater reuse as a demonstration and training center. Design and operating experience for the demon...To solve the water shortage problem, an artificial groundwater recharge system will be constructed in Beijing for wastewater reuse as a demonstration and training center. Design and operating experience for the demonstration plant was gained through pilot tests of advanced treatment technologies with soil infiltration of well treated secondary effluent. The test results showed that the selected treatment technology meets the recommended water quality criteria for groundwater recharge and the gas chromatography-mass spectrometer (GC/MS) analysis results showed significantly improved water quality.展开更多
Population growth, urbanization, water resources pollution, environmental awareness, uneven distribution of water resources and water scarcity have necessitated water reuse especially in arid and semi-arid countries. ...Population growth, urbanization, water resources pollution, environmental awareness, uneven distribution of water resources and water scarcity have necessitated water reuse especially in arid and semi-arid countries. Influent and effluent data of chemical and biological analyses from four wastewater treatment plants (WWTPs) in the Sedibeng district municipality (SDM) were used to assess the viability of water reuse. Available worldwide water reuse criteria of Water Reclamation Plants (WRPs) for different reuse options were used to characterize the SDM’s four WWTPs for potable water, power and steel industrial water reuse. Only WWTP4 does not meet the influent design criteria of the New Goreangab WRP in Windhoek, Namibia of 43 mg/l and the DWAF general limit of discharge of 75 mg/l used by Beaufort West WRP in South Africa for COD. WWTP2 and 4 do not meet the DWAF general limit of 25 mg/l for suspended solids. Some of the water quality parameters of the effluents from these plants were non-compliant to the requirements for reuse in power generation and steel manufacturing. However, the implementation of advance treatment technologies such as membrane or advanced oxidation processes (AOPs) as part of the treatment train in a potential WRP would address the water quality issues. Water reclamation of SDM effluent either through direct (DPR) or indirect potable (IPR) water reuse, power generation and steel manufacturing industry has the potential of reuse in the Southern Gauteng region. The success of the selected option would be depended on cost effectiveness, stakeholder commitment and public acceptance of the reuse strategy.展开更多
Constructed wetland (CW) is the preferred means of controlling water quality because of its natural treatment mechanisms and function as a secondary or tertiary treatment unit. CW is increasingly applied in Korea fo...Constructed wetland (CW) is the preferred means of controlling water quality because of its natural treatment mechanisms and function as a secondary or tertiary treatment unit. CW is increasingly applied in Korea for secondary effluent of livestock wastewater treatment. This study was conducted to recognize the characteristics of contaminants in the accumulated sediment at the bottom soil layer and to reduce the phosphorus release from sediments of the free water surface CW for the treatment of secondary piggery wastewater effluent from a livestock wastewater treatment facility. The results revealed that the dominant phosphorus existence types at near the inlet of the CW were non-apatite phosphorus (59%) and residual phosphorus (32%) suggesting that most of the particles of the influent are made up of inorganic materials and dead cells. Sediment accumulation is important when determining the long-term maintenance requirements over the lifetime of CW. Continuous monitoring will be performed for a further assessment of the CW system and design.展开更多
An advanced anaerobic biofilter(AF) was introduced for the treatment of coal gasification wastewater(CGW),and effluent recirculation was adopted to enhance phenol removal and methane production.The results indicat...An advanced anaerobic biofilter(AF) was introduced for the treatment of coal gasification wastewater(CGW),and effluent recirculation was adopted to enhance phenol removal and methane production.The results indicated that AF was reliable in treating diluted CGW,while its efficiency and stability were seriously reduced when directly treating raw CGW.However,its performance could be greatly enhanced by effluent recirculation.Under optimal effluent recirculation of 0.5 to the influent,concentrations of chemical oxygen demand(COD) and total phenol in the effluent could reach as low as 234.0 and 14.2 mg/L,respectively.Also,the rate of methane production reached 169.0 m L CH_4/L/day.Though CGW seemed to restrain the growth of anaerobic microorganisms,especially methanogens,the inhibition was temporary and reversible,and anaerobic bacteria presented strong tolerance.The activities of methanogens cultivated in CGW could quickly recover on feeding with glucose wastewater(GW).However,the adaptability of anaerobic bacteria to the CGW was very poor and the activity of methanogens could not be improved by long-term domestication.By analysis using the Haldane model,it was further confirmed that high effluent recirculation could result in high activity for hydrolytic bacteria and substrate affinity for toxic matters,but only suitable effluent recirculation could result in high methanogenic activity.展开更多
The use of modeling and simulation has developed into a critical tool for the sustainable management of wastewater, especially when it comes to replicating the complex biochemical procedures required for fertilizer ef...The use of modeling and simulation has developed into a critical tool for the sustainable management of wastewater, especially when it comes to replicating the complex biochemical procedures required for fertilizer effluent treatment, which calls for a significant amount of wastewater-related data. The biological improvement of a urea fertilizer effluent via GPS* simulation was carried out in this work using a methodical process. Using established analytical techniques, temperature, total suspended solids (TSS), biochemical oxygen demand (BOD), total phosphorus (T/), chemical oxygen demand (COD), total nitrogen (TN), total nitrate (NO<sub>3</sub>), electric conductivity (EC), turbidity, residual chlorine, urea, NH<sub>3</sub>, and heavy metals (Cu, Cd, Cr, Pb, Ni, and Fe) were assessed. The research revealed that the measured values from the fertilizer factory outfall effluent had high concentrations of all the physicochemical water quality indicators, with the exception of TSS, PO<sub>4</sub><sup>-</sup>, SO<sub>4</sub><sup>-</sup>, and NO<sub>3</sub><sup>-</sup>. These concentrations are higher compared to the authorized limits or suggested values by the Federal Environmental Protection Agency (FEPA). To improve the therapy biologically, however, a modeling and simulation program (GPS-X, version 8.0) was used with the physicochemical information gathered from the studied sample. The results of the treated water simulation showed that the concentrations of BOD<sub>5</sub> and COD had been significantly reduced by 35% and 44%, respectively. Additionally, it was discovered that total phosphorus (TP), nitrate (N), and total nitrogen (TN) were all within the permitted FEPA limit. The results revealed good treatment performance of the wastewater with increasing concentration of acetic acid and sodium hydroxide. Hence, the results of this research work identify the need for proper treatment of fertilizer industry effluents prior to their release into the environment.展开更多
The overall goal of this study is investigating the environmental impacts of using wastewater effluent of industrial states in irrigation of green space. For this purpose, industrial state of Shokouhieh in Qom Provinc...The overall goal of this study is investigating the environmental impacts of using wastewater effluent of industrial states in irrigation of green space. For this purpose, industrial state of Shokouhieh in Qom Province in central of Iran was selected as a case study. Firstly, the quality and quantity of inputting wastewater into refinery and outputting wastewater effluent were measured on important parameters of pH, TDS, TSS, COD, BOD and wastewater temperature in refinery laboratory of industrial state of Qom Shokouhieh during 12 months from March 2012 to March 2013. Then analysis of chemical, biological and physical indicators of irrigation wastewater (effluent) and measurement of heavy metals were done in June 2012 and January 2013 according to the standards instruction for the water and wastewater treatment. Also, heavy metals, EC, pH, and Mg2+, Ca2+, Na+, k+ of soil of industrial estate of Qom Shokouhieh were studied. Then, Rapid Impact Assessment Method (RIAM) and Entropy Method were used to analyze the data. In Rapid Impact Assessment Method, socio-cultural, physicochemical, biological and economic environments get the highest negative impacts respectively. In Entropy Method after weighting the environmental factors, public health and other disease parameters with the weight of 0.147, soil chemical properties with the weight of 0.136, soil toxicity with the weight of 0.126 were allocated the first rate up to the third rate respectively. After comparing the results of these two methods with each other, the main limitation of using wastewater effluent of industrial estate of Qom Shokouhie in irrigation of green space is entering chemical pollutants (nitrate) into groundwater, salinity and toxicity of soil of industrial state and endangerment of workers and labors public health who work in industrial state of Qom Shokouhie (specially the labors who exposure directly with the wastewater effluent and labors work in refinery).展开更多
Biogenic particles discharged by wastewater treatment plants play important roles in receiving water because of the large specific surface area and good mobility of the particles. In this study, the changes induced in...Biogenic particles discharged by wastewater treatment plants play important roles in receiving water because of the large specific surface area and good mobility of the particles. In this study, the changes induced in biogenic particles by natural sunlight were investigated to understand the phototransformation of the particles in the receiving waters. The results showed that photoexposure resulted in significant decreases in the sizes of the biogenic particles but that photoexposure did not impact the zeta potentials. In addition, the photodissolution of biogenic particulate organic matter(POM) led to the generation of biogenic dissolved organic matter(DOM). Characterization using excitation–emission matrix(EEM) spectroscopy showed that photoexposure changed both the shapes and the intensities of the EEM spectra of the biogenic POM; the regions of the T1 and T2 peaks were susceptible to photoexposure. Modeling by parallel factor analysis(PARAFAC) decomposed the EEMs of the biogenic POM into four valid components, i.e., terrestrial or microbial humic-like substances, tryptophan-like proteins, tyrosinelike proteins and hydrophobic proteins. The humic-like substances in the biogenic POM from the effluents were subject to lower decreases(17.0 % and 11.6 %).Throughout the entire incubation time, the PARAFAC components in the biogenic DOM were dominated by elimination mechanisms rather than by production through photodissolution of the biogenic POM.展开更多
基金Supported in part by the Metropolitan Sewer District of Greater Cincinnati (MSDGC) under Master Services Agreement (No.85X10431)Task Order (No. 0210000209)Rachael Rheaume was supported by the Academic Year 2009-10 REU Program funded by the NSF Type 1 STEP Project (No. DUE-0756921)
文摘The capability of Chlorella vulgaris to remove nitrogen in the form of ammonia and/or ammonium ions from wastewater effluent in a local wastewater treatment plant (i.e., the Mill Creek Plant in Cincinnati, Ohio, U.S.A.) was studied. The wastewater effluent leaving the plant was found to include high concentra- tions of nitrogen (7.7±0.19 mg/L) (ammonia (NH3) and/or ammonium ion (NH4+)) and total inorganic carbon (58.6±0.28 mg/L) at pH 7, and to be suitable for growing Chlorella vulgaris. When Chlorella vulgaris was cul- tivated in a batch mode under a closed system, half of the nitrogen concentration was dramatically removed in 48 h after a 24-h lag-phase period. Total inorganic carbon concentration also concomitantly decreased during the rapid growth-phase. The total biomass weight gained during the entire cultivation period balanced out well with the total amount of inorganic carbon and nitrogen removed from the culture medium. These results indicate that wastewater can be synergistically used to polish residual nutrients in wastewater as well as to cultivate microalgae for biofuel production.
基金Supported by the Major Research Project of the Ninth-Five Plan (19911995 ) of China (No.95 - 90 9- 0 3 - 0 3 )
文摘To solve the water shortage problem, an artificial groundwater recharge system will be constructed in Beijing for wastewater reuse as a demonstration and training center. Design and operating experience for the demonstration plant was gained through pilot tests of advanced treatment technologies with soil infiltration of well treated secondary effluent. The test results showed that the selected treatment technology meets the recommended water quality criteria for groundwater recharge and the gas chromatography-mass spectrometer (GC/MS) analysis results showed significantly improved water quality.
文摘Population growth, urbanization, water resources pollution, environmental awareness, uneven distribution of water resources and water scarcity have necessitated water reuse especially in arid and semi-arid countries. Influent and effluent data of chemical and biological analyses from four wastewater treatment plants (WWTPs) in the Sedibeng district municipality (SDM) were used to assess the viability of water reuse. Available worldwide water reuse criteria of Water Reclamation Plants (WRPs) for different reuse options were used to characterize the SDM’s four WWTPs for potable water, power and steel industrial water reuse. Only WWTP4 does not meet the influent design criteria of the New Goreangab WRP in Windhoek, Namibia of 43 mg/l and the DWAF general limit of discharge of 75 mg/l used by Beaufort West WRP in South Africa for COD. WWTP2 and 4 do not meet the DWAF general limit of 25 mg/l for suspended solids. Some of the water quality parameters of the effluents from these plants were non-compliant to the requirements for reuse in power generation and steel manufacturing. However, the implementation of advance treatment technologies such as membrane or advanced oxidation processes (AOPs) as part of the treatment train in a potential WRP would address the water quality issues. Water reclamation of SDM effluent either through direct (DPR) or indirect potable (IPR) water reuse, power generation and steel manufacturing industry has the potential of reuse in the Southern Gauteng region. The success of the selected option would be depended on cost effectiveness, stakeholder commitment and public acceptance of the reuse strategy.
基金provided by the Korean Ministry of Environment (MOE)
文摘Constructed wetland (CW) is the preferred means of controlling water quality because of its natural treatment mechanisms and function as a secondary or tertiary treatment unit. CW is increasingly applied in Korea for secondary effluent of livestock wastewater treatment. This study was conducted to recognize the characteristics of contaminants in the accumulated sediment at the bottom soil layer and to reduce the phosphorus release from sediments of the free water surface CW for the treatment of secondary piggery wastewater effluent from a livestock wastewater treatment facility. The results revealed that the dominant phosphorus existence types at near the inlet of the CW were non-apatite phosphorus (59%) and residual phosphorus (32%) suggesting that most of the particles of the influent are made up of inorganic materials and dead cells. Sediment accumulation is important when determining the long-term maintenance requirements over the lifetime of CW. Continuous monitoring will be performed for a further assessment of the CW system and design.
文摘An advanced anaerobic biofilter(AF) was introduced for the treatment of coal gasification wastewater(CGW),and effluent recirculation was adopted to enhance phenol removal and methane production.The results indicated that AF was reliable in treating diluted CGW,while its efficiency and stability were seriously reduced when directly treating raw CGW.However,its performance could be greatly enhanced by effluent recirculation.Under optimal effluent recirculation of 0.5 to the influent,concentrations of chemical oxygen demand(COD) and total phenol in the effluent could reach as low as 234.0 and 14.2 mg/L,respectively.Also,the rate of methane production reached 169.0 m L CH_4/L/day.Though CGW seemed to restrain the growth of anaerobic microorganisms,especially methanogens,the inhibition was temporary and reversible,and anaerobic bacteria presented strong tolerance.The activities of methanogens cultivated in CGW could quickly recover on feeding with glucose wastewater(GW).However,the adaptability of anaerobic bacteria to the CGW was very poor and the activity of methanogens could not be improved by long-term domestication.By analysis using the Haldane model,it was further confirmed that high effluent recirculation could result in high activity for hydrolytic bacteria and substrate affinity for toxic matters,but only suitable effluent recirculation could result in high methanogenic activity.
文摘The use of modeling and simulation has developed into a critical tool for the sustainable management of wastewater, especially when it comes to replicating the complex biochemical procedures required for fertilizer effluent treatment, which calls for a significant amount of wastewater-related data. The biological improvement of a urea fertilizer effluent via GPS* simulation was carried out in this work using a methodical process. Using established analytical techniques, temperature, total suspended solids (TSS), biochemical oxygen demand (BOD), total phosphorus (T/), chemical oxygen demand (COD), total nitrogen (TN), total nitrate (NO<sub>3</sub>), electric conductivity (EC), turbidity, residual chlorine, urea, NH<sub>3</sub>, and heavy metals (Cu, Cd, Cr, Pb, Ni, and Fe) were assessed. The research revealed that the measured values from the fertilizer factory outfall effluent had high concentrations of all the physicochemical water quality indicators, with the exception of TSS, PO<sub>4</sub><sup>-</sup>, SO<sub>4</sub><sup>-</sup>, and NO<sub>3</sub><sup>-</sup>. These concentrations are higher compared to the authorized limits or suggested values by the Federal Environmental Protection Agency (FEPA). To improve the therapy biologically, however, a modeling and simulation program (GPS-X, version 8.0) was used with the physicochemical information gathered from the studied sample. The results of the treated water simulation showed that the concentrations of BOD<sub>5</sub> and COD had been significantly reduced by 35% and 44%, respectively. Additionally, it was discovered that total phosphorus (TP), nitrate (N), and total nitrogen (TN) were all within the permitted FEPA limit. The results revealed good treatment performance of the wastewater with increasing concentration of acetic acid and sodium hydroxide. Hence, the results of this research work identify the need for proper treatment of fertilizer industry effluents prior to their release into the environment.
文摘The overall goal of this study is investigating the environmental impacts of using wastewater effluent of industrial states in irrigation of green space. For this purpose, industrial state of Shokouhieh in Qom Province in central of Iran was selected as a case study. Firstly, the quality and quantity of inputting wastewater into refinery and outputting wastewater effluent were measured on important parameters of pH, TDS, TSS, COD, BOD and wastewater temperature in refinery laboratory of industrial state of Qom Shokouhieh during 12 months from March 2012 to March 2013. Then analysis of chemical, biological and physical indicators of irrigation wastewater (effluent) and measurement of heavy metals were done in June 2012 and January 2013 according to the standards instruction for the water and wastewater treatment. Also, heavy metals, EC, pH, and Mg2+, Ca2+, Na+, k+ of soil of industrial estate of Qom Shokouhieh were studied. Then, Rapid Impact Assessment Method (RIAM) and Entropy Method were used to analyze the data. In Rapid Impact Assessment Method, socio-cultural, physicochemical, biological and economic environments get the highest negative impacts respectively. In Entropy Method after weighting the environmental factors, public health and other disease parameters with the weight of 0.147, soil chemical properties with the weight of 0.136, soil toxicity with the weight of 0.126 were allocated the first rate up to the third rate respectively. After comparing the results of these two methods with each other, the main limitation of using wastewater effluent of industrial estate of Qom Shokouhie in irrigation of green space is entering chemical pollutants (nitrate) into groundwater, salinity and toxicity of soil of industrial state and endangerment of workers and labors public health who work in industrial state of Qom Shokouhie (specially the labors who exposure directly with the wastewater effluent and labors work in refinery).
基金supported by the New Century Excellent Talents in University from the Ministry of Education of China (NCET-11-0537)the Fundamental Research Funds for the Central Universities (12lgpy52)
文摘Biogenic particles discharged by wastewater treatment plants play important roles in receiving water because of the large specific surface area and good mobility of the particles. In this study, the changes induced in biogenic particles by natural sunlight were investigated to understand the phototransformation of the particles in the receiving waters. The results showed that photoexposure resulted in significant decreases in the sizes of the biogenic particles but that photoexposure did not impact the zeta potentials. In addition, the photodissolution of biogenic particulate organic matter(POM) led to the generation of biogenic dissolved organic matter(DOM). Characterization using excitation–emission matrix(EEM) spectroscopy showed that photoexposure changed both the shapes and the intensities of the EEM spectra of the biogenic POM; the regions of the T1 and T2 peaks were susceptible to photoexposure. Modeling by parallel factor analysis(PARAFAC) decomposed the EEMs of the biogenic POM into four valid components, i.e., terrestrial or microbial humic-like substances, tryptophan-like proteins, tyrosinelike proteins and hydrophobic proteins. The humic-like substances in the biogenic POM from the effluents were subject to lower decreases(17.0 % and 11.6 %).Throughout the entire incubation time, the PARAFAC components in the biogenic DOM were dominated by elimination mechanisms rather than by production through photodissolution of the biogenic POM.