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Organic chloramines in chlorine-based disinfected water systems: A critical review 被引量:12
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作者 Zuo Tong How Ina Kristiana +2 位作者 Francesco Busetti Kathryn L.Linge Cynthia A.Joll 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第8期2-18,共17页
This paper is a critical review of current knowledge of organic chloramines in water systems,including their formation, stability, toxicity, analytical methods for detection, and their impact on drinking water treatme... This paper is a critical review of current knowledge of organic chloramines in water systems,including their formation, stability, toxicity, analytical methods for detection, and their impact on drinking water treatment and quality. The term organic chloramines may refer to any halogenated organic compounds measured as part of combined chlorine(the difference between the measured free and total chlorine concentrations), and may include N-chloramines,N-chloramino acids, N-chloraldimines and N-chloramides. Organic chloramines can form when dissolved organic nitrogen or dissolved organic carbon react with either free chlorine or inorganic chloramines. They are potentially harmful to humans and may exist as an intermediate for other disinfection by-products. However, little information is available on the formation or occurrence of organic chloramines in water due to a number of challenges. One of the biggest challenges for the identification and quantification of organic chloramines in water systems is the lack of appropriate analytical methods. In addition, many of the organic chloramines that form during disinfection are unstable, which results in difficulties in sampling and detection. To date research has focussed on the study of organic monochloramines.However, given that breakpoint chlorination is commonly undertaken in water treatment systems, the formation of organic dichloramines should also be considered. Organic chloramines can be formed from many different precursors and pathways. Therefore, studying the occurrence of their precursors in water systems would enable better prediction and management of their formation. 展开更多
关键词 Amino acids Disinfection by-products Organic chloramines N-chloramine Drinking water quality Organic bromamines Organic iodamines
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Spectrophotometric Determination of Lodine in Soils by Chloramine T-Tetrabase System 被引量:16
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作者 胡兰 杨刚 《Agricultural Science & Technology》 CAS 2009年第5期13-14,17,共3页
Optimized the experimental conditions of determination of trace iodine in soil in chloramine T-Tetrabase system, and analysis the national standards material, the results showed that the measured values was to be iden... Optimized the experimental conditions of determination of trace iodine in soil in chloramine T-Tetrabase system, and analysis the national standards material, the results showed that the measured values was to be identical with recommended values with a detection limit of 0.16 μg/g, and the relative standard deviation was less than 8%, the whole process was short in time and simple, so it was applicable to the determination of trace iodine in batches. 展开更多
关键词 IODINE Chloramine T-Tetrabase system Catalytic spectrophotometry SOIL
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Biological stability in drinking water: a regression analysis of influencing factors 被引量:1
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作者 LUWei ZHANGXiao-jian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第3期395-398,共4页
Some parameters, such as assimilable organic carbon(AOC), chloramine residual, water temperature, and water residence time, were measured in drinking water from distribution systems in a northern city of China. The me... Some parameters, such as assimilable organic carbon(AOC), chloramine residual, water temperature, and water residence time, were measured in drinking water from distribution systems in a northern city of China. The measurement results illustrate that when chloramine residual is more than 0.3 mg/L or AOC content is below 50 μg/L, the biological stability of drinking water can be controlled. Both chloramine residual and AOC have a good relationship with Heterotrophic Plate Counts(HPC)(log value), the correlation coefficient was -0.64 and 0.33, respectively. By regression analysis of the survey data, a statistical equation is presented and it is concluded that disinfectant residual exerts the strongest influence on bacterial growth and AOC is a suitable index to assess the biological stability in the drinking water. 展开更多
关键词 AOC biological stability HPC residual chloramines regression analysis
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Research on Stability of Spectrophotometric Determination of Iodine in Soils by Chloramine T-tetrabase System
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作者 胡兰 孙丽 《Agricultural Science & Technology》 CAS 2017年第2期266-269,共4页
Factors affecting the stability of iodine in soil by Chloramine T-Tetrabase system were studied. The results showed that good measurement stability could be achieved by adding ascorbic acid.
关键词 Chloramine T-tetrabase system IODINE STABILITY
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Simultaneous Control of Microorganisms and Disinfection By-products by Sequential Chlorination 被引量:4
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作者 CHAO CHEN XIAO-JIAN ZHANG +1 位作者 WEN-JIE HE HONG-DA HAN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第2期119-125,共7页
Objective To introduce a new sequential chlorination disinfection process in which short-term free chlorine and chloramine are sequentially added. Methods Pilot tests of this sequential chlorination were carried out i... Objective To introduce a new sequential chlorination disinfection process in which short-term free chlorine and chloramine are sequentially added. Methods Pilot tests of this sequential chlorination were carried out in a drinking water plant. Results The sequential chlorination disinfection process had the same or better efficiency on microbe (including virus) inactivation compared with the free chlorine disinfection process. There seemed to be some synergetic disinfection effect between free chlorine and monochloramine because they attacked different targets. The sequential chlorination disinfection process resulted in 35.7%-77.0% TTHM formation and 36.6%-54.8% THAA5 formation less than the free chlorination process. The poorer the water quality was, the more advantage the sequential chlorination disinfection had over the free chlorination. Conclusion This process takes advantages of free chlorine's quick inactivation of microorganisms and chloramine's low disinfection by-product (DBP) yield and long-term residual effect, allowing simultaneous control of microbes and DBPs in an effective and economic way. 展开更多
关键词 DISINFECTION Free chlorine CHLORAMINE Disinfection by-products MICROORGANISMS
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Using chloramine as a coagulant aid in enhancing coagulation of Yellow River water in China 被引量:1
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作者 YANG Wei CHEN Jie +3 位作者 LI Xing LIANG Heng HE Wen-jie LI Gui-bai 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第9期1475-1481,共7页
Considering that contaminated raw water mostly contains high Ammonia-N and a majority of water treatment plants use prechlorination process in China, efficiency of chloramines as a coagulant aid in enhancing coagulati... Considering that contaminated raw water mostly contains high Ammonia-N and a majority of water treatment plants use prechlorination process in China, efficiency of chloramines as a coagulant aid in enhancing coagulation was investigated by Jar stirring and pilot-scale tests, using Yellow River water containing high concentration of natural organic matters (NOM) and bromide in winter. The jar tests results showed that, compared with no preoxidation, preformed chloramine apparently decreased the turbidity of settled and filtered water with low dosage (2.0 rag/L), and the aid-coagulation efficiency was further enhanced with the increase of chlorine (Cl2) to Ammonia-N (N) ratio. Pilot-scale studies indicated that, in comparison to the case without preoxidation, the turbidity removal efficiency of flotation and filtration effluent water was significantly improved, the particle counts of filtered water were decreased 63.4%, the average rate of filter head loss was reduced 18.2%, and filter run time was prolonged 15.7%. Therefore, chloramine preoxidation may substantially enhance the particle separation efficiency. 展开更多
关键词 PREOXIDATION CHLORAMINE Pilot plant TURBIDITY Particle counts Filter run time
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Importance of Bromine-Substituted DBP’s in Drinking Water
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作者 Lisa Wulff Enos Inniss Tom Clevenger 《Journal of Water Resource and Protection》 2013年第8期28-34,共7页
Significant fractions of bromine-substituted disinfection byproducts (DBPs)—particularly trihalomethanes (THMs)— have been observed to form during treatment of water from the Missouri River. THM speciation was also ... Significant fractions of bromine-substituted disinfection byproducts (DBPs)—particularly trihalomethanes (THMs)— have been observed to form during treatment of water from the Missouri River. THM speciation was also noted to follow a seasonal pattern during a 2.5-year period, during which samples were collected multiple times per month. Although some treatment processes were effective at reducing the chloroform formation potential, no treatment used at this utility significantly reduced the formation of the three bromine-substituted THM species. Using chloramination rather than free chlorination for secondary disinfection, however, was effective at limiting increases in the concentration of all four regulated THM species in the distribution system. 展开更多
关键词 DISINFECTION By-Products BROMINE MISSOURI River Treatment CHLORINATION CHLORAMINATION
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Effects of Br−on NDMA Formation During Chloramination:a Review of Influencing Factors,Mechanisms,and Control
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作者 XIA Ruanjunjie LIAO Xiaobin +2 位作者 LIU Tianze GAO Menglan CHEN Chao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2023年第3期370-377,共8页
For the invasion of seawater and the stress of human activities,bromide ion(Br−)exists widely in drinking water sources,and it was found to influence the formation of non-brominated but carcinogenic nitrogen-containin... For the invasion of seawater and the stress of human activities,bromide ion(Br−)exists widely in drinking water sources,and it was found to influence the formation of non-brominated but carcinogenic nitrogen-containing disinfection by-product nitroso-dimethylamine(NDMA)during chloramination(NH2Cl).The presence of Br−leads to the formation of bromine-active species,such as bromamines(NH2Br),bromochloramine(NHClBr),as well as hypobromous acid(HOBr),which are more reactive with NDMA precursors than chlorine-active species,so might promote NDMA generation.This review mainly focuses on the influencing laws,as well as the factors(disinfection conditions and characteristics of water matrixes)that affected NMDA formation during chloramination with Br−.In addition,the possible influencing pathways are discussed.Finally,based on the above summary,measures pertaining to reduce the impact of Br−on NDMA production are concluded.This review would provide a theoretical reference for drinking water treatment plants to deal with bromine-containing water during chloramination. 展开更多
关键词 Bromide ion Disinfection by-product Nitrosodimethylamine(NDMA) CHLORAMINATION
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Impact of total organic carbon and chlorine to ammonia ratio on nitrification in a bench-scale drinking water distribution system 被引量:3
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作者 Yongji ZHANG Lingling ZHOU +2 位作者 Guo ZENG Huiping DENG Guibai LI 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2010年第4期430-437,共8页
Nitrification occurs in chloraminated drinking water systems and is affected by water quality parameters.The aim of this study was to investigate the impact of total organic carbon and chlorine to ammonia ratio on nit... Nitrification occurs in chloraminated drinking water systems and is affected by water quality parameters.The aim of this study was to investigate the impact of total organic carbon and chlorine to ammonia ratio on nitrification potential in a simulated drinking water distribution system as during chloramination.The occurrence of nitrification and activity of nitrifying bacteria was primarily monitored using four rotating annular bioreactors(RAB)with different chlorine to ammonia ratios and total organic carbon(TOC)levels.The results indicated that nitrification occurred despite at a low influent concentration of ammonia,and a high concentration of nitrite nitrogen was detected in the effluent.The study illustrated that reactors 1(R1)and 3(R3),with higher TOC levels,produced more nitrite nitrogen,which was consistent with the ammonia-oxidizing bacteria(AOB)counts,and was linked to a relatively more rapid decay of chloramines in comparison to their counterparts(R2 and R4).The AOB and HPC counts were correlated during the biofilm formation with the establishment of nitrification.Biofilm AOB abundance was also higher in the high TOC reactors compared with the low TOC reactors.The chlorine to ammonia ratio did not have a significant impact on the occurrence of nitrification.Bulk water with a high TOC level supported the occurrence of nitrification,and AOB development occurred at all examined chlorine to ammonia dose ratios(3:1 or 5:1). 展开更多
关键词 NITRIFICATION drinking water ammoniaoxidizing bacteria(AOB) chloramines organic carbon heterotrophic bacteria
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Effect of pipe material and low level disinfectants on biofilm development in a simulated drinking water distribution system 被引量:1
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作者 Ling-ling ZHOU Yong-ji ZHANG Gui-bai LI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第5期725-731,共7页
The efficiency of chlorine and chloramines disinfection on biofilm development in a simulated drinking water distribution system was investigated by using heterotrophic bacterial spread plate technique. The experiment... The efficiency of chlorine and chloramines disinfection on biofilm development in a simulated drinking water distribution system was investigated by using heterotrophic bacterial spread plate technique. The experiments were carried out with four annular reactors (ARs) with stainless steel (SS) or copper (Cu) material slides. The results showed that there were fewer bacteria attached to Cu slides without a disinfectant compared with those attached to SS slides. When the water was disinfected with chloramines, the heterotrophic plate counts (HPCs) on the biofilm attached to the Cu slides were significantly lower (by 3.46 log CFU/cm2) than those attached to the SS slides. Likewise, the biofilm HPC numbers on the Cu slides were slightly lower (by 1.19 log CFU/cm2) than those on the SS slides disinfected with chlorine. In a quasi-steady state, the HPC levels on Cu slides can be reduced to 3.0 log CFU/cm2 with chlorine and to about 0.9 log CFU/cm2 with chloramines. The addition of chloramines resulted in a more efficient reduction of biofilm heterotrophic bacteria than did chlorine. We concluded that the chlorine and chloramines levels usually employed in water distribution system were not sufficient to prevent the growth and development of microbial biofilm. The combination of copper pipe slides and chloramines as the disinfectant was the most efficient combination to bring about diminished bacterial levels. 展开更多
关键词 Copper (Cu) Stainless steel (SS) BIOFILM Heterotrophic plate counts (HPCs) CHLORINE chloramines
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Concentrations of disinfection by-products in swimming pool following modifications of the water treatment process:An exploratory study 被引量:1
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作者 Robert Tardif Manuel Rodriguez +2 位作者 Cyril Catto Ginette Charest-Tardif Sabrina Simard 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第8期163-172,共10页
The formation and concentration of disinfection by-products(DBPs) in pool water and the ambient air vary according to the type of water treatment process used. This exploratory study was aimed at investigating the s... The formation and concentration of disinfection by-products(DBPs) in pool water and the ambient air vary according to the type of water treatment process used. This exploratory study was aimed at investigating the short-term impact of modifications of the water treatment process on traditional DBP levels(e.g., trihalomethanes(THMs), chloramines) and emerging DBPs(e.g., Halonitromethanes, Haloketones, NDMA) in swimming pool water and/or air. A sampling program was carried to understand the impact of the following changes made successively to the standard water treatment process: activation of ultraviolet(UV)photoreactor, halt of air stripping with continuation of air extraction from the buffer tank,halt of air stripping and suppression of air extraction from the buffer tank, suppression of the polyaluminium silicate sulfate(PASS) coagulant. UV caused a high increase of Halonitromethanes(8.4 fold), Haloketones(2.1 fold), and THMs in the water(1.7 fold) and, of THMs in the air(1.6 fold) and contributed to reducing the level of chloramines in the air(1.6fold) and NDMA in the water(2.1 fold). The results highlight the positive impact of air stripping in reducing volatile contaminants. The PASS did not change the presence of DBPs, except for the THMs, which decrease slightly with the use of this coagulant. This study shows that modifications affecting the water treatment process can rapidly produce important and variable impacts on DBP levels in water and air and suggests that implementation of any water treatment process to reduce DBP levels should take into account the specific context of each swimming pool. 展开更多
关键词 Disinfection by-products Swimming pool UV rays Air stripping chloramines Emerging DBPs NDMA
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Formation of regulated and unregulated disinfection byproducts during chlorination and chloramination: Roles of dissolved organic matter type, bromide, and iodide 被引量:4
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作者 Yunsi Liu Keqiang Liu +2 位作者 Michael J.Plewa Tanju Karanfil Chao Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第7期151-160,共10页
Algal blooms and wastewater effluents can introduce algal organic matter(AOM) and effluent organic matter(Ef OM) into surface waters, respectively. In this study, the impact of bromide and iodide on the formation of h... Algal blooms and wastewater effluents can introduce algal organic matter(AOM) and effluent organic matter(Ef OM) into surface waters, respectively. In this study, the impact of bromide and iodide on the formation of halogenated disinfection byproducts(DBPs) during chlorination and chloramination from various types of dissolved organic matter(DOM, e.g., natural organic matter(NOM), AOM, and Ef OM) were investigated based on the data collected from literature. In general, higher formation of trihalomethanes(THMs) and haloacetic acids(HAAs) was observed in NOM than AOM and Ef OM, indicating high reactivities of phenolic moieties with both chlorine and monochloramine. The formation of haloacetaldehydes(HALs), haloacetonitriles(HANs) and haloacetamides(HAMs) was much lower than THMs and HAAs. Increasing initial bromide concentrations increased the formation of THMs, HAAs, HANs, and HAMs, but not HALs. Bromine substitution factor(BSF) values of DBPs formed in chlorination decreased as specific ultraviolet absorbance(SUVA) increased. AOM favored the formation of iodinated THMs(I-THMs) during chloramination using preformed chloramines and chlorination-chloramination processes. Increasing prechlorination time can reduce the I-THM concentrations because of the conversion of iodide to iodate, but this increased the formation of chlorinated and brominated DBPs. In an analogous way, iodine substitution factor(ISF) values of I-THMs formed in chloramination decreased as SUVA values of DOM increased. Compared to chlorination, the formation of noniodinated DBPs is low in chloramination. 展开更多
关键词 Disinfection byproducts Natural organic matter Algal organic matter Effluent organic matter BROMIDE IODIDE CHLORINATION CHLORAMINATION
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Formation and cytotoxicity of a new disinfection by-product (DBP) phenazine by chloramination of water containing diphenylamine 被引量:3
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作者 Wenjun Zhou Linjie Lou +2 位作者 Lifang Zhu Zhimin Li Lizhong Zhu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第7期1217-1224,共8页
Disinfection by-products (DBPs) in drinking water have caused worldwide concern due to their potential carcinogenic effects. The formation of phenazine from diphenylamine (DPhA) chloramination was studied and its ... Disinfection by-products (DBPs) in drinking water have caused worldwide concern due to their potential carcinogenic effects. The formation of phenazine from diphenylamine (DPhA) chloramination was studied and its cytotoxicities for two human cancer cells were also investigated. Phenazine was detected synchronously with the consumption of DPhA by chloramination, which further confirmed that the new DBP phenazine can be produced along with N-nitrosodiphenylamine (NDPhA) from DPhA chloramination. The formation of phenazine had a maximum molar yield with solution pH increasing from 5.0 to 9.0, with phenazine as the main product for DPhA chloramination at lower pH, but higher pH favored the formation of NDPhA. Thus, solution pH is the key factor in controlling the formation of phenazine and NDPhA. Both the initial DPhA and chloramine concentrations did not show a significant effect on the molar yields of phenazine, although increasing the chloramine concentration could speed up the reaction rate of DPhA with chloramines. The cytotoxicity assays showed that phenazine had significant cell-specific toxicity towards T24 (bladder cancer cell lines) and HepG2 (hepatic tumor cell lines) cells with IC50 values of 0.50 and 2.04 mmol/L, respectively, and T24 cells being more sensitive to phenazine than HepG2 cells. The ICs0 values of phenazine, DPhA, and NDPhA for T24 cells were of the same order of magnitude and the cytotoxicity of phenazine for T24 cells was slightly lower than that of NDPhA (IC50, 0.16 mmol/L), suggesting that phenazine in drinking water may have an adverse effect on human health. 展开更多
关键词 PHENAZINE DIPHENYLAMINE disinfection by-product CHLORAMINATION CYTOTOXICITY
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Formation and speciation of disinfection byproducts during chlor(am)ination of aquarium seawater 被引量:2
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作者 Haiting Zhang Huiyu Dong +3 位作者 Craig Adams Zhimin Qiang Gang Luan Lei Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第7期116-124,共9页
The chemistry associated with the disinfection of aquarium seawater is more complicated than that of freshwater, therefore limited information is available on the formation and speciation of disinfection byproducts(D... The chemistry associated with the disinfection of aquarium seawater is more complicated than that of freshwater, therefore limited information is available on the formation and speciation of disinfection byproducts(DBPs) in marine aquaria. In this study, the effects of organic precursors, bromide(Br-) and pre-ozonation on the formation and speciation of several typical classes of DBPs, including trihalomethanes(THM4), haloacetic acids(HAAs),iodinated trihalomethanes(I-THMs), and haloacetamides(HAc Ams), were investigated during the chlorination/chloramination of aquarium seawater. Results indicate that with an increase in dissolved organic carbon concentration from 4.5 to 9.4 mg/L, the concentrations of THM4 and HAAs increased by 3.2-7.8 times under chlorination and by 1.1-2.3 times under chloramination. An increase in Br-concentration from 3 to 68 mg/L generally enhanced the formation of THM4, I-THMs and HAc Ams and increased the bromine substitution factors of all studied DBPs as well, whereas it impacted insignificantly on the yield of HAAs. Pre-ozonation with 1 mg/L O3 dose substantially reduced the formation of all studied DBPs in the subsequent chlorination and I-THMs in the subsequent chloramination. Because chloramination produces much lower amounts of DBPs than chlorination, it tends to be more suitable for disinfection of aquarium seawater. 展开更多
关键词 Disinfection byproducts CHLORINATION CHLORAMINATION PRE-OZONATION Bromine substitution factorAquarium seawater
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Formation and control of nitrogenous DBPs from Western Australian source waters: Investigating the impacts of high nitrogen and bromide concentrations 被引量:9
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作者 Ina Kristiana Deborah Liew +2 位作者 Rita K.Henderson Cynthia A.Joll Kathryn L.Linge 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第8期102-115,共14页
We studied the formation of four nitrogenous DBPs(N-DBPs) classes(haloacetonitriles,halonitromethanes, haloacetamides, and N-nitrosamines), as well as trihalomethanes and total organic halogen(TOX), after chlori... We studied the formation of four nitrogenous DBPs(N-DBPs) classes(haloacetonitriles,halonitromethanes, haloacetamides, and N-nitrosamines), as well as trihalomethanes and total organic halogen(TOX), after chlorination or chloramination of source waters. We also evaluated the relative and additive toxicity of N-DBPs and water treatment options for minimisation of N-DBPs. The formation of halonitromethanes, haloacetamides, and N-nitrosamines was higher after chloramination and positively correlated with dissolved organic nitrogen or total nitrogen. N-DBPs were major contributors to the toxicity of both chlorinated and chloraminated waters. The strong correlation between bromide concentration and the overall calculated DBP additive toxicity for both chlorinated and chloraminated source waters demonstrated that formation of brominated haloacetonitriles was the main contributor to toxicity. Ozone–biological activated carbon treatment was not effective in removing N-DBP precursors. The occurrence and formation of N-DBPs should be investigated on a case-by-case basis, especially where advanced water treatment processes are being considered to minimise their formation in drinking waters, and where chloramination is used for final disinfection. 展开更多
关键词 Haloacetonitriles Haloacetamides Halonitromethanes N-nitrosamines Chlorination Chloramination
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Biostability in distribution systems in one city in southern China: Characteristics, modeling and control strategy 被引量:7
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作者 Pinpin Lu Xiaojian Zhang +3 位作者 Chiqian Zhang Zhangbin Niu Shuguang Xie Chao Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第2期323-331,共9页
This study investigated the bacterial regrowth in drinking water distribution systems receiving finished water from an advanced drinking water treatment plant in one city in southem China. Thirteen nodes in two water ... This study investigated the bacterial regrowth in drinking water distribution systems receiving finished water from an advanced drinking water treatment plant in one city in southem China. Thirteen nodes in two water supply zones with different aged pipelines were selected to monitor water temperature, dissolved oxygen (DO), chloramine residual, assimilable organic carbon (AOC), and heterotrophic plate counts (HPC). Regression and principal component analyses indicated that HPC had a strong correlation with chloramine residual. Based on Chick-Watson's Law and the Monod equation, biostability curves under different conditions were developed to achieve the goal of HPC 100 CFU/mL. The biostability curves could interpret the scenario under various AOC concentrations and predict the required chloramine residual concentration under the condition of high AOC level. The simulation was also carded out to predict the scenario with a stricter HPC goal (≤50 CFU/mL) and determine the required chloramine residual. The biological regrowth control strategy was assessed using biostability curve analysis. The results indicated that maintaining high chloramine residual concentration was the most practical way to achieve the goal of HPC ≤ 100 CFU/mL. Biostability curves could be a very useful tool for biostability control in distribution systems. This work could provide some new insights towards biostability control in real distribution systems. 展开更多
关键词 bacterial regrowth distribution system biostability AOC chloramine residual
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Chloramination of wastewater effluent: Toxicity and formation of disinfection byproducts 被引量:8
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作者 Julien Le Roux Michael J.Plewa +3 位作者 Elizabeth D.Wagner Maolida Nihemaiti Azra Dad Jean-Philippe Croué 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第8期135-145,共11页
The reclamation and disinfection of waters impacted by human activities(e.g., wastewater effluent discharges) are of growing interest for various applications but has been associated with the formation of toxic nitr... The reclamation and disinfection of waters impacted by human activities(e.g., wastewater effluent discharges) are of growing interest for various applications but has been associated with the formation of toxic nitrogenous disinfection byproducts(N-DBPs). Monochloramine used as an alternative disinfectant to chlorine can be an additional source of nitrogen in the formation of N-DBPs. Individual toxicity assays have been performed on many DBPs, but few studies have been conducted with complex mixtures such as wastewater effluents. In this work, we compared the cytotoxicity and genotoxicity of wastewater effluent organic matter(Ef OM) before and after chloramination. The toxicity of chloraminated Ef OM was significantly higher than the toxicity of raw Ef OM, and the more hydrophobic fraction(HPO)isolated on XAD-8 resin was more toxic than the fraction isolated on XAD-4 resin.More DBPs were also isolated on the XAD-8 resin. N-DBPs(i.e., haloacetonitriles or haloacetamides) were responsible for the majority of the cytotoxicity estimated from DBP concentrations measured in the XAD-8 and XAD-4 fractions(99.4% and 78.5%, respectively).Measured DBPs accounted for minor proportions of total brominated and chlorinated products, which means that many unknown halogenated compounds were formed and can be responsible for a significant part of the toxicity. Other non-halogenated byproducts(e.g.,nitrosamines) may contribute to the toxicity of chloraminated effluents as well. 展开更多
关键词 Disinfection byproducts Chloramination Toxicity Wastewater XAD resins Haloacetonitriles Haloacetamides
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Influencing factors of disinfection byproducts formation during chloramination of Cyclops metabolite solutions 被引量:5
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作者 Xingbin Sun Lei Sun +2 位作者 Ying Lu Jing Zhang Kejing Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第3期575-580,共6页
Effects of reaction time, chlorine dosage, pH and temperature on the formation of disinfection byproducts (DBPs), were investigated during the chloramination of Cyclops metabolite solutions. The results showed that ... Effects of reaction time, chlorine dosage, pH and temperature on the formation of disinfection byproducts (DBPs), were investigated during the chloramination of Cyclops metabolite solutions. The results showed that some species of DBPs like trichloromethane (TCM), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) could accumulate to their respective stable values with a progressive elevation in reaction time and monochloramine concentration. And 1,1,1-2-trichloropropanone (1,1,1- TCP) content decreased correspondingly with a continuous increase of reaction time. The amounts of chloral hydrate (CH), chloropicrin (TCNM), 1,1,1-TCP and DCAA firstly increased and then decreased with increasing monochloramine doses. Higher temperature resulted in a decrease of CH, dichloroacetonitrile (DCAN), 1,1-dichloropropanone (1,1-DCP), 1,1,1-TCP, DCAA and TCAA concentration, pH affected the formation of the different DBPs distinctly. TCM accumulateded with the increase of pH under 9, and DCAA, TCAA, CH and 1,1-DCP decreased continuously with increasing pH from 5 to 10, and other DBPs had the maximum concentrations at pH 6-7. 展开更多
关键词 chloramination Cyclops metabolite solutions DBPs
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Comparative mammalian cell cytotoxicity of wastewater with elevated bromide and iodide after chlorination,chloramination, or ozonation 被引量:5
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作者 Shengkun Dong Thanh H.Nguyen Michael J.Plewa 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第8期296-301,共6页
Recycling wastewater is becoming more common as communities around the world try to better control their water resources against an increased frequency of either prolonged droughts or intense flooding. For communities... Recycling wastewater is becoming more common as communities around the world try to better control their water resources against an increased frequency of either prolonged droughts or intense flooding. For communities in coastal areas, wastewaters may contain elevated levels of bromide(Br^-) and iodide(I^-) from seawater intrusion or high mineral content of source waters. Disinfection of such wastewater is mandatory to prevent the spread of pathogens, however little is known about the toxicity of wastewater after disinfection in the presence of Br^-and I^-. In this study we compared the induction of chronic cytotoxicity in mammalian cells in samples of municipal secondary wastewater effluent amended with elevated levels of Br^-/I^-after disinfection by chlorine, chloramines or ozone to identify which disinfection process generated wastewater with the lowest level of adverse biological response. Chlorination increased mammalian cell cytotoxicity by 5times as compared to non-disinfected controls. Chloramination produced disinfected wastewater that expressed 6.3 times more cytotoxicity than the non-disinfected controls and was 1.3 times more cytotoxic than the chlorinated samples. Ozonation produced wastewater with cytotoxicity comparable to the non-disinfected controls and was at least 4times less cytotoxic than the chlorine disinfected wastewaters. These results indicate that compared to chlorination and chloramination, ozonation of wastewater with high Br^-/Ilevels yielded the lowest mammalian cell cytotoxicity, suggesting its potential as a more favorable method to disinfect wastewater with minimizing the biological toxicity in mind. 展开更多
关键词 Cytotoxicity Ozonation Chlorination Chloramination Wastewater Bromide Iodide Disinfection
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A balancing act: Optimizing free chlorine contact time to minimize iodo-DBPs, NDMA, and regulated DBPs in chloraminated drinking water 被引量:1
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作者 Matthew A.Bloodgood Sridevi Anduri Chowdary +3 位作者 Eric J.Daiber Honglan Shi Caroline O.Granger Susan D.Richardson 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第7期315-325,共11页
Many drinking water treatment plants in the U.S. have switched from chlorination to chloramination to lower levels of regulated trihalomethane(THM) and haloacetic acid(HAA) disinfection byproducts(DBPs) in drinking wa... Many drinking water treatment plants in the U.S. have switched from chlorination to chloramination to lower levels of regulated trihalomethane(THM) and haloacetic acid(HAA) disinfection byproducts(DBPs) in drinking water and meet the current regulations. However, chloramination can also produce other highly toxic/carcinogenic, unregulated DBPs: iodoacids, iodo-THMs, and N-nitrosodimethylamine(NDMA). In practice, chloramines are generated by the addition of chlorine with ammonia, and plants use varying amounts of free chlorine contact time prior to ammonia addition to effectively kill pathogens and meet DBP regulations. However, iodo-DBPs and nitrosamines are generally not considered in this balancing of free chlorine contact time. The goal of our work was to determine whether an optimal free chlorine contact time could be established in which iodo-DBPs and NDMA could be minimized, while keeping regulated THMs and HAAs below their regulatory limits. The effect of free chlorine contact time was evaluated for the formation of six iodo-trihalomethanes(iodo-THMs), six iodo-acids, and NDMA during the chloramination of drinking water. Ten different free chlorine contact times were examined for two source waters with different dissolved organic carbon(DOC) and bromide/iodide. For the low DOC water at pH 7 and 8, an optimized free chlorine contact time of up to 1 h could control regulated THMs and HAAs, as well as iodo-DBPs and NDMA. For the high DOC water, a free chlorine contact time of 5 min could control iodo-DBPs and NDMA at both p Hs, but the regulated DBPs could exceed the regulations at pH 7. 展开更多
关键词 Iodo-DBPs NDMA Disinfection byproducts CHLORAMINE Drinking water Free chlorine contact time
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