R. Tanna, M. Moncur, S. J. Birks, J. Gibson, C. Ptacek, B. Mayer, M. Wieser, F. Wrona, K. Munkittrick
Distinguishing municipal wastewater effluent (MWWE) from other industrial effluents or through an urbanized watershed can be challenging. In complex receiving environments, linking environmental responses to specific compounds or effluents is not always straight forward. In order to characterize the inherent complexity of tracing MWWE in aquatic systems influenced by multiple stressors, a proposed multi-tracer suite is intended to highlight areas of potential biological concern. Characterization and quantification of effluent exposure to aquatic biota in this manner is essential to shape policies intended to encourage wastewater infrastructure development (i.e. treatment plant upgrade) and broader environmental management. This paper describes the use of a comprehensive suite of tracers that includes isotopes in support of a core surveillance program, demonstrating its effectiveness both empirically and with respect to diagnostic value contributed to monitoring programs.
{"title":"Utility of a multi-tracer approach as a component of adaptive monitoring for municipal wastewater impacts","authors":"R. Tanna, M. Moncur, S. J. Birks, J. Gibson, C. Ptacek, B. Mayer, M. Wieser, F. Wrona, K. Munkittrick","doi":"10.2166/wqrj.2020.004","DOIUrl":"https://doi.org/10.2166/wqrj.2020.004","url":null,"abstract":"\u0000 Distinguishing municipal wastewater effluent (MWWE) from other industrial effluents or through an urbanized watershed can be challenging. In complex receiving environments, linking environmental responses to specific compounds or effluents is not always straight forward. In order to characterize the inherent complexity of tracing MWWE in aquatic systems influenced by multiple stressors, a proposed multi-tracer suite is intended to highlight areas of potential biological concern. Characterization and quantification of effluent exposure to aquatic biota in this manner is essential to shape policies intended to encourage wastewater infrastructure development (i.e. treatment plant upgrade) and broader environmental management. This paper describes the use of a comprehensive suite of tracers that includes isotopes in support of a core surveillance program, demonstrating its effectiveness both empirically and with respect to diagnostic value contributed to monitoring programs.","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/wqrj.2020.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49255124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this research, the adsorption of the Direct Red 23 dye from synthetic textile wastewater using nanoclay was studied in a batch system. The properties of nanoclay were investigated by scanning electron microscope, Fourier transform infrared, and EDX analysis. The specific surface area of the nanoclay was determined using Sear's method. The results revealed that with increasing adsorbent dose and contact time and decreasing pH, ionic strength, and adsorbate concentration, dye removal efficiency has increased. Nanoclay could remove 99.4% dye from the solution containing 50 mg/L dye at 30 min. The results indicated that dye removal followed pseudo-second-order kinetic (R2 > 0.99) and the Langmuir isotherm. According to the findings, nanoclay is an effective adsorbent for direct dye removal from wastewater.
{"title":"Kinetic and equilibrium studies on the adsorption of Direct Red 23 dye from aqueous solution using montmorillonite nanoclay","authors":"A. Mahvi, A. Dalvand","doi":"10.2166/wqrj.2019.008","DOIUrl":"https://doi.org/10.2166/wqrj.2019.008","url":null,"abstract":"In this research, the adsorption of the Direct Red 23 dye from synthetic textile wastewater using nanoclay was studied in a batch system. The properties of nanoclay were investigated by scanning electron microscope, Fourier transform infrared, and EDX analysis. The specific surface area of the nanoclay was determined using Sear's method. The results revealed that with increasing adsorbent dose and contact time and decreasing pH, ionic strength, and adsorbate concentration, dye removal efficiency has increased. Nanoclay could remove 99.4% dye from the solution containing 50 mg/L dye at 30 min. The results indicated that dye removal followed pseudo-second-order kinetic (R2 > 0.99) and the Langmuir isotherm. According to the findings, nanoclay is an effective adsorbent for direct dye removal from wastewater.","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/wqrj.2019.008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47028371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Harmful algal blooms (HABs) in aquatic ecosystems are of concern worldwide. This review deals with how jurisdictions around the world are addressing this water quality issue to inform recommendations regarding nutrient loading and HABs in Missisquoi Bay-Lake Champlain and Lake Memphremagog; transboundary lakes located in the USA and Canada that suffer from symptoms of eutrophication. A global scan of the literature resulted in the consideration of 12 case studies of large water bodies within large watersheds, excluding in-lake geoengineering approaches. Although all of the systems experience excessive nutrient loading, they vary in two key ways: sources of nutrients and manifestations of eutrophication ranging from HABs, to limited recreational uses, to the additional complexity of internal loadings and fish kills, up to drinking water shutdowns. The case studies were analyzed with respect to four categories of approaches, namely: (i) regulatory; (ii) incentive-based; (iii) risk mitigation; and (iv) outreach, engagement, and educational. We found that the management frameworks are based on integrated watershed management planning and national standards. National water quality standards, however, are not stringent enough to prevent HABs. Overall, identified case studies did not successfully remediate HABs, they simply managed them.
{"title":"A global scan of how the issue of nutrient loading and harmful algal blooms is being addressed by governments, non-governmental organizations, and volunteers","authors":"É. Foulon, A. Rousseau, Glenn A. Benoy, R. North","doi":"10.2166/wqrj.2019.013","DOIUrl":"https://doi.org/10.2166/wqrj.2019.013","url":null,"abstract":"\u0000 Harmful algal blooms (HABs) in aquatic ecosystems are of concern worldwide. This review deals with how jurisdictions around the world are addressing this water quality issue to inform recommendations regarding nutrient loading and HABs in Missisquoi Bay-Lake Champlain and Lake Memphremagog; transboundary lakes located in the USA and Canada that suffer from symptoms of eutrophication. A global scan of the literature resulted in the consideration of 12 case studies of large water bodies within large watersheds, excluding in-lake geoengineering approaches. Although all of the systems experience excessive nutrient loading, they vary in two key ways: sources of nutrients and manifestations of eutrophication ranging from HABs, to limited recreational uses, to the additional complexity of internal loadings and fish kills, up to drinking water shutdowns. The case studies were analyzed with respect to four categories of approaches, namely: (i) regulatory; (ii) incentive-based; (iii) risk mitigation; and (iv) outreach, engagement, and educational. We found that the management frameworks are based on integrated watershed management planning and national standards. National water quality standards, however, are not stringent enough to prevent HABs. Overall, identified case studies did not successfully remediate HABs, they simply managed them.","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/wqrj.2019.013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48126886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Both anthropogenic activities and natural factors affect river water in quantity and quality, while anthropogenic activities have been often blamed to cause water quality temporal degradation. In addition, riverine water quality displays intra-annual/seasonal variations, which are often more prominent than inter-annual variations. The intra-annual variations in water quality, which are attracting the attention of managers and policy-makers, beg the question of how to better manage riverine water quality at a finer time resolution. The natural factors, in particular, the hydro-meteorological variables, could be the primary drivers of the intra-annual variations of riverine water quality. Therefore, this paper examined the association between riverine water quality and one hydro-meteorological variable (flow) with the focus on their relationship at the intra-annual timescale on three selected rivers in Alberta, Canada. The results demonstrated that flow drives intra-annual variation of riverine water quality in general. Moreover, some water quality parameters responded to flow distinctively at three flow regimes (low, medium, and high flows). Water quality parameters were categorized into eight groups according to their responses to flow at the flow regimes. These implied the challenges in water quality management while providing insight into how to formulate more effective water management strategies.
{"title":"Water quality response to river flow regime at three major rivers in Alberta","authors":"S. Rostami, Jianxun He, Q. Hassan","doi":"10.2166/wqrj.2019.033","DOIUrl":"https://doi.org/10.2166/wqrj.2019.033","url":null,"abstract":"\u0000 Both anthropogenic activities and natural factors affect river water in quantity and quality, while anthropogenic activities have been often blamed to cause water quality temporal degradation. In addition, riverine water quality displays intra-annual/seasonal variations, which are often more prominent than inter-annual variations. The intra-annual variations in water quality, which are attracting the attention of managers and policy-makers, beg the question of how to better manage riverine water quality at a finer time resolution. The natural factors, in particular, the hydro-meteorological variables, could be the primary drivers of the intra-annual variations of riverine water quality. Therefore, this paper examined the association between riverine water quality and one hydro-meteorological variable (flow) with the focus on their relationship at the intra-annual timescale on three selected rivers in Alberta, Canada. The results demonstrated that flow drives intra-annual variation of riverine water quality in general. Moreover, some water quality parameters responded to flow distinctively at three flow regimes (low, medium, and high flows). Water quality parameters were categorized into eight groups according to their responses to flow at the flow regimes. These implied the challenges in water quality management while providing insight into how to formulate more effective water management strategies.","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/wqrj.2019.033","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48582705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study examined the responses of a population of brook stickleback (Culaea inconstans) exposed to pulp mill effluent at Jackfish Bay, Lake Superior, Canada, in May 2007 and May 2011. Brook stickleback were extirpated from the effluent-receiving site, presumably due to anoxia after this period. Females at the effluent-receiving site had significantly larger gonad sizes in 2007 and 2011. In 2011, effluent-exposed female gonadal development was significantly advanced when compared with reference sites; they were the second most mature when compared among three different reference sites. Analysis of 7-ethoxyresorufin-O-deethylase activity revealed that effluent-receiving site females had greater CYP1A induction in 2007 and significantly greater CYP1A induction in 2011. Effluent-receiving site males showed significantly reduced CYP1A induction in 2007 and significantly greater induction in 2011. Chemical evaluation of sediment from the receiving environment showed elevated levels of resin acids and the polycyclic aromatic hydrocarbon, retene. Higher condition factors and more mature gonads were consistent with higher winter and spring temperatures modified by effluent or by lake vs. stream environments. Overall, effects on effluent-exposed brook stickleback were not consistent with reported effects in white sucker exposed to the same effluent in previous studies. This article has been made Open Access thanks to the kind support of CAWQ/ACQE (https://www.cawq.ca).
本研究于2007年5月和2011年5月在加拿大苏必利尔湖的Jackfish Bay研究了接触纸浆厂废水的棘鱼种群(Culaea inconstans)。小溪棘鱼被从污水接收处清除，大概是由于这段时间后缺氧。2007年和2011年，污水接收点的雌性性腺尺寸显著增大。2011年，与参考地点相比，暴露于污水的女性性腺发育显著提前;在三个不同的参考站点中，它们是第二成熟的。对7-乙氧基间苯甲醚- o -去乙基酶活性的分析显示，2007年，污水接收部位雌性的CYP1A诱导程度更高，2011年的CYP1A诱导程度显著更高。2007年，污水接收区雄鱼CYP1A诱导显著降低，2011年显著增强。接收环境中沉积物的化学评价显示树脂酸和多环芳烃(retene)含量升高。较高的条件因子和更成熟的性腺与较高的冬季和春季温度相一致，这些温度是由流出物或湖泊与溪流环境改变的。总的来说，对暴露于废水的小溪棘鱼的影响与先前研究中暴露于相同废水的白色吸盘的报道效果不一致。感谢CAWQ/ACQE (https://www.cawq.ca)的大力支持，本文已开放获取。
{"title":"Effects of habitat and pulp and paper mill contamination on a population of brook stickleback (Culaea inconstans)","authors":"Gillian Z MacDonald, N. Hogan, M. V. D. Heuvel","doi":"10.2166/WQRJ.2019.005","DOIUrl":"https://doi.org/10.2166/WQRJ.2019.005","url":null,"abstract":"\u0000 This study examined the responses of a population of brook stickleback (Culaea inconstans) exposed to pulp mill effluent at Jackfish Bay, Lake Superior, Canada, in May 2007 and May 2011. Brook stickleback were extirpated from the effluent-receiving site, presumably due to anoxia after this period. Females at the effluent-receiving site had significantly larger gonad sizes in 2007 and 2011. In 2011, effluent-exposed female gonadal development was significantly advanced when compared with reference sites; they were the second most mature when compared among three different reference sites. Analysis of 7-ethoxyresorufin-O-deethylase activity revealed that effluent-receiving site females had greater CYP1A induction in 2007 and significantly greater CYP1A induction in 2011. Effluent-receiving site males showed significantly reduced CYP1A induction in 2007 and significantly greater induction in 2011. Chemical evaluation of sediment from the receiving environment showed elevated levels of resin acids and the polycyclic aromatic hydrocarbon, retene. Higher condition factors and more mature gonads were consistent with higher winter and spring temperatures modified by effluent or by lake vs. stream environments. Overall, effects on effluent-exposed brook stickleback were not consistent with reported effects in white sucker exposed to the same effluent in previous studies.\u0000 This article has been made Open Access thanks to the kind support of CAWQ/ACQE (https://www.cawq.ca).","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/WQRJ.2019.005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48031075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. A. Aziz, N. Ibrahim, M. Alazaiza, Cheong Kah Win
Addition of composite adsorbent Zeliac to a riverbank filtration system can enhance the removal of micropollutants in polluted river water. This paper aims to investigate the potential use of Zeliac to remove pollutants, such as total coliform, Escherichia coli, suspended solids (SSs), UV254 and colour, from the Sungai Kerian River. Two columns filled with Zeliac of different granular sizes were established and continuously run for 15 days. Maximum SS removals of 93% and 98% were recorded for Zeliac with granular sizes of 1.18–2 mm and 0.42–0.6 mm, respectively. Meanwhile, 99%–100% of total coliform was removed from the system, and no E. coli was detected in the effluent up to 15 h of the experiments. High removal efficiencies were also recorded for UV254 (>80%) and colour (>90%). Granular size showed no significant effect on the removal of the selected parameters, especially total coliform and E. coli. Zeliac showed good potential as an adsorbent to improve water treatment.
{"title":"The removal efficiency of total coliform, Escherichia coli, suspended solids, UV254 and colour using Zeliac filter in riverbank filtration system","authors":"H. A. Aziz, N. Ibrahim, M. Alazaiza, Cheong Kah Win","doi":"10.2166/WQRJ.2019.052","DOIUrl":"https://doi.org/10.2166/WQRJ.2019.052","url":null,"abstract":"\u0000 Addition of composite adsorbent Zeliac to a riverbank filtration system can enhance the removal of micropollutants in polluted river water. This paper aims to investigate the potential use of Zeliac to remove pollutants, such as total coliform, Escherichia coli, suspended solids (SSs), UV254 and colour, from the Sungai Kerian River. Two columns filled with Zeliac of different granular sizes were established and continuously run for 15 days. Maximum SS removals of 93% and 98% were recorded for Zeliac with granular sizes of 1.18–2 mm and 0.42–0.6 mm, respectively. Meanwhile, 99%–100% of total coliform was removed from the system, and no E. coli was detected in the effluent up to 15 h of the experiments. High removal efficiencies were also recorded for UV254 (>80%) and colour (>90%). Granular size showed no significant effect on the removal of the selected parameters, especially total coliform and E. coli. Zeliac showed good potential as an adsorbent to improve water treatment.","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/WQRJ.2019.052","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49393255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sophie Felleiter, K. Mcdermott, Geof Hall, P. Sheth, A. Majury
Private water wells provide drinking water for an estimated 4.1 million households in Canada yet remain understudied in the context of microbial water quality or human health impacts. As there exists little systematic surveillance for enteric infections or outbreaks related to well water sources, consumers may be at risk of waterborne infectious diseases. A standard protocol in Ontario requires 200 mL of water, collected, and submitted by well owners, half of which is used to analyze for Escherichia coli and total coliforms (TCs). The aim of this study was to determine the efficacy of testing small water volumes and to survey for other contaminants in addition to bacterial indicators to inform pathogen prevalence and fecal source in drinking water wells. Samples were assessed for E. coli and TCs, by culture, and genetic markers of Bacteroides spp., Campylobacter spp., Salmonella spp., and Shiga toxin-producing E. coli, using qPCR. The source of fecal contamination varied by the geographic region and may be explained by septic tank density and underlying geology, among other factors. A small number of samples (1.9%) showed the evidence of contamination with enteric pathogens. Lastly, E. coli measured by qPCR, as opposed to culture, correlated more strongly to Bacteroides markers.
{"title":"Exploring private water wells for fecal sources and evidence of pathogen presence in the context of current testing practices for potability in Ontario","authors":"Sophie Felleiter, K. Mcdermott, Geof Hall, P. Sheth, A. Majury","doi":"10.2166/WQRJ.2019.035","DOIUrl":"https://doi.org/10.2166/WQRJ.2019.035","url":null,"abstract":"\u0000 Private water wells provide drinking water for an estimated 4.1 million households in Canada yet remain understudied in the context of microbial water quality or human health impacts. As there exists little systematic surveillance for enteric infections or outbreaks related to well water sources, consumers may be at risk of waterborne infectious diseases. A standard protocol in Ontario requires 200 mL of water, collected, and submitted by well owners, half of which is used to analyze for Escherichia coli and total coliforms (TCs). The aim of this study was to determine the efficacy of testing small water volumes and to survey for other contaminants in addition to bacterial indicators to inform pathogen prevalence and fecal source in drinking water wells. Samples were assessed for E. coli and TCs, by culture, and genetic markers of Bacteroides spp., Campylobacter spp., Salmonella spp., and Shiga toxin-producing E. coli, using qPCR. The source of fecal contamination varied by the geographic region and may be explained by septic tank density and underlying geology, among other factors. A small number of samples (1.9%) showed the evidence of contamination with enteric pathogens. Lastly, E. coli measured by qPCR, as opposed to culture, correlated more strongly to Bacteroides markers.","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":"1 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/WQRJ.2019.035","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43263533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Kumar, Kongkona Saikia, Gerard Neeraj, H. Cabana, Vaidyanathan Kumar
The novelty of the current study deals with the application of magnetic nanosorbent, chitosan-coated magnetic nanoparticles (cMNPs), to be utilized for the management of lignocellulosic bio-refinery wastewater (LBW) containing three heavy metals and 26 phenolic compounds. The magnetic property of the adsorbent, confirmed by elemental and vibrating sample magnetometer analysis (saturation magnetization of 26.96 emu/g), allows easy separation of the particles in the presence of an external magnetic field. At pH 6.0, with optimized adsorbent dosage of 2.0 g/L and 90 min contact time, maximum removal of phenol (46.2%), copper (42.2%), chromium (18.7%) and arsenic (2.44%) was observed. The extent of removal of phenolic compounds was in the order: polysubstituted > di-substituted > mono-substituted > cresol > phenol. Overall, the adsorption capacity (qe) of cMNPs varies among the different contaminants in the following manner: copper (1.03 mg/g), chromium (0.20 mg/g), arsenic (0.04 mg/g) and phenol (0.56 mg/g). Post-adsorption, retrieving the cMNPs using an external magnetic field followed by single-step desorption via acid–base treatment is attractive for implementation in industrial settings. Reusability of the adsorbent was studied by recycling the cMNPs for five consecutive rounds of adsorption followed by desorption, at the end of which, cMNPs retained 20% of their initial adsorption capacity.
{"title":"Remediation of bio-refinery wastewater containing organic and inorganic toxic pollutants by adsorption onto chitosan-based magnetic nanosorbent","authors":"A. Kumar, Kongkona Saikia, Gerard Neeraj, H. Cabana, Vaidyanathan Kumar","doi":"10.2166/wqrj.2019.003","DOIUrl":"https://doi.org/10.2166/wqrj.2019.003","url":null,"abstract":"The novelty of the current study deals with the application of magnetic nanosorbent, chitosan-coated magnetic nanoparticles (cMNPs), to be utilized for the management of lignocellulosic bio-refinery wastewater (LBW) containing three heavy metals and 26 phenolic compounds. The magnetic property of the adsorbent, confirmed by elemental and vibrating sample magnetometer analysis (saturation magnetization of 26.96 emu/g), allows easy separation of the particles in the presence of an external magnetic field. At pH 6.0, with optimized adsorbent dosage of 2.0 g/L and 90 min contact time, maximum removal of phenol (46.2%), copper (42.2%), chromium (18.7%) and arsenic (2.44%) was observed. The extent of removal of phenolic compounds was in the order: polysubstituted > di-substituted > mono-substituted > cresol > phenol. Overall, the adsorption capacity (qe) of cMNPs varies among the different contaminants in the following manner: copper (1.03 mg/g), chromium (0.20 mg/g), arsenic (0.04 mg/g) and phenol (0.56 mg/g). Post-adsorption, retrieving the cMNPs using an external magnetic field followed by single-step desorption via acid–base treatment is attractive for implementation in industrial settings. Reusability of the adsorbent was studied by recycling the cMNPs for five consecutive rounds of adsorption followed by desorption, at the end of which, cMNPs retained 20% of their initial adsorption capacity.","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/wqrj.2019.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45809351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the present study, two non-linear mathematical modelling approaches, namely, extreme learning machine (ELM) and multilayer perceptron neural network (MLPNN) were developed to predict daily dissolved oxygen (DO) concentrations. Water quality data from four urban rivers in the backwater zone of the Three Gorges Reservoir, China were used. The water quality data selected consisted of daily observed water temperature, pH, permanganate index, ammonia nitrogen, electrical conductivity, chemical oxygen demand, total nitrogen, total phosphorus and DO. The accuracy of the ELM model was compared with the standard MLPNN using several error statistics such as root mean squared error, mean absolute error, the coefficient of correlation and the Willmott index of agreement. Results showed that the ELM and MLPNN models perform well for the Wubu River, acceptably for the Yipin River and moderately for the Huaxi River, while poor model performance was obtained at the Tributary of Huaxi River. Model performance is negatively correlated with pollution level in each river. The MLPNN model slightly outperforms the ELM model in DO prediction. Overall, it can be concluded that MLPNN and ELM models can be applied for DO prediction in low-impacted rivers, while they may not be appropriate for DO modelling for highly polluted rivers. This article has been made Open Access thanks to the kind support of CAWQ/ACQE (https://www.cawq.ca).
{"title":"Prediction of dissolved oxygen in urban rivers at the Three Gorges Reservoir, China: extreme learning machines (ELM) versus artificial neural network (ANN)","authors":"Senlin Zhu, S. Heddam","doi":"10.2166/WQRJ.2019.053","DOIUrl":"https://doi.org/10.2166/WQRJ.2019.053","url":null,"abstract":"\u0000 In the present study, two non-linear mathematical modelling approaches, namely, extreme learning machine (ELM) and multilayer perceptron neural network (MLPNN) were developed to predict daily dissolved oxygen (DO) concentrations. Water quality data from four urban rivers in the backwater zone of the Three Gorges Reservoir, China were used. The water quality data selected consisted of daily observed water temperature, pH, permanganate index, ammonia nitrogen, electrical conductivity, chemical oxygen demand, total nitrogen, total phosphorus and DO. The accuracy of the ELM model was compared with the standard MLPNN using several error statistics such as root mean squared error, mean absolute error, the coefficient of correlation and the Willmott index of agreement. Results showed that the ELM and MLPNN models perform well for the Wubu River, acceptably for the Yipin River and moderately for the Huaxi River, while poor model performance was obtained at the Tributary of Huaxi River. Model performance is negatively correlated with pollution level in each river. The MLPNN model slightly outperforms the ELM model in DO prediction. Overall, it can be concluded that MLPNN and ELM models can be applied for DO prediction in low-impacted rivers, while they may not be appropriate for DO modelling for highly polluted rivers.\u0000 This article has been made Open Access thanks to the kind support of CAWQ/ACQE (https://www.cawq.ca).","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/WQRJ.2019.053","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46281358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mehrnaz Sadrnourmohammadi, K. Brezinski, B. Gorczyca
The effect of ozonation on the structural and chemical characteristics of natural organic matter (NOM) and its isolated humic fractions, humic acid (HA) and fulvic acid, were studied using Fourier transform infrared coupled to attenuated total reflectance (FTIR-ATR), ultraviolet/visible (UV/Vis) spectroscopy, and synchronous scanning fluorescence (SSF) spectroscopy. The results were linked to the effect of ozonation on trihalomethane formation potential (THMfp) reduction for water standards with high THM precursors. Results showed that ozonation at a dose of 1 mg ozone/mg dissolved organic carbon (DOC) was capable of reducing DOC, UV absorbance at 254 nm (UV254), and THMfp by up to 42%, 95%, and 89% for the HA water standard, respectively. The study of UV/Vis, FTIR-ATR, and SSF revealed trends showing that ozone can alter the composition of DOC in the water standards, causing a significant reduction in aromaticity. The reduction of UV254 for each ozonated sample also affirms that ozone mainly targets aromatic moieties contained in NOM. FTIR-ATR results showed that the reduction of unsaturated functional groups, including aromatic rings and C = C bonds in the water standards tested, were the main components impacted by ozone application. SSF results also revealed that ozonation decreases the fluorescence intensity of the maximum peak – as well as the whole spectra.
{"title":"Ozonation of natural organic matter and aquatic humic substances: the effects of ozone on the structural characteristics and subsequent trihalomethane formation potential","authors":"Mehrnaz Sadrnourmohammadi, K. Brezinski, B. Gorczyca","doi":"10.2166/wqrj.2020.011","DOIUrl":"https://doi.org/10.2166/wqrj.2020.011","url":null,"abstract":"\u0000 The effect of ozonation on the structural and chemical characteristics of natural organic matter (NOM) and its isolated humic fractions, humic acid (HA) and fulvic acid, were studied using Fourier transform infrared coupled to attenuated total reflectance (FTIR-ATR), ultraviolet/visible (UV/Vis) spectroscopy, and synchronous scanning fluorescence (SSF) spectroscopy. The results were linked to the effect of ozonation on trihalomethane formation potential (THMfp) reduction for water standards with high THM precursors. Results showed that ozonation at a dose of 1 mg ozone/mg dissolved organic carbon (DOC) was capable of reducing DOC, UV absorbance at 254 nm (UV254), and THMfp by up to 42%, 95%, and 89% for the HA water standard, respectively. The study of UV/Vis, FTIR-ATR, and SSF revealed trends showing that ozone can alter the composition of DOC in the water standards, causing a significant reduction in aromaticity. The reduction of UV254 for each ozonated sample also affirms that ozone mainly targets aromatic moieties contained in NOM. FTIR-ATR results showed that the reduction of unsaturated functional groups, including aromatic rings and C = C bonds in the water standards tested, were the main components impacted by ozone application. SSF results also revealed that ozonation decreases the fluorescence intensity of the maximum peak – as well as the whole spectra.","PeriodicalId":23720,"journal":{"name":"Water Quality Research Journal","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2020-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2166/wqrj.2020.011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45589542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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