医院污水处理中ClO_2检测方法的改进研究

本研究用R5法制取ClO2 对医院污水进行消毒处理 ,针对碘量法测定剩余ClO2 时的不足 ,通过控制溶液pH值、加入稳定剂、活化剂和掩蔽剂的方法对其进行改进 ,实现了将溶液中ClO2 、Cl2 、ClO- 2 、ClO- 3区分测定的目的。实验表明 ,改进后的检测方法能够真实准确地反映溶液中剩余的ClO2 。     

ClO2和Cl2混合消毒剂对氯仿形成的影响

研究了ClO2和Cl2混合水溶液对黄腐酸、间苯二酚、间苯三酚和3,5-甲苯二酚等9种THMs前驱物在ClO2/Cl2各种配比、前驱物含量、反应pH、反应时间和温度等不同条件下对氯仿形成的影响.结果表明,随着ClO2占混合消毒剂中质量分数的增加,形成氯仿量减少,在混合消毒剂中ClO2的质量分数为25%、50%和75%时,CHCl3生成量分别减少55%～65%,70%～86%和80%～93%;直到ClO2占90%时,CHCl3降低率才达到95%～99%.欲较彻底地控制氯仿的生成,ClO2的质量分数必须大于90%.这为生产高纯ClO2发生器以及用高纯ClO2消毒的必要性提供了重要的科学依据.     

ClO_2氧化,混凝沉降法处理煤气洗涤水的研究

根据煤气洗涤水的性质,用ClO2 氧化除酚,SL和PAM混凝沉降除悬浮物的方法处理煤气洗涤水。实验结果表明,经处理后废水中的主要污染物酚、焦油和悬浮物等去除率都很高,该水完全可以满足回用要求。     

水消毒过程无机副产物生成模型的建立

探讨了饮用水ClO2消毒无机副产物ClO2和ClO3-产生预测模型建立的必要性.分析了模型建立的方法与过程,并提出存在的不足与建议.     

高氯酸盐污染土壤及地下水的植物-微生物修复研究进展

高氯酸盐（ClO4-）是一种新兴的持久性污染物,其环境污染问题引起了高度关注.由于人为和自然来源造成土壤及地下水大范围ClO4-污染,控制与修复ClO4-污染环境成为新的研究热点,其中植物和微生物修复最具应用前景,但我国相关研究甚少.本文总结了ClO4-污染土壤及地下水植物修复的作用机制及影响因素,包括植物吸收积累、植...     

环境友好消毒剂二氧化氯的灭活效果和消毒副产物

消毒是一个非常重要水处理单元过程,但常规消毒剂氯气会产生具有"三致"作用的消毒副产物.二氧化氯(ClO2)灭活效率高,消毒副产物的危害小,是一种环境友好消毒剂.总结了ClO2对水中细菌、病毒、乙肝表面抗原(HBsAg)、原生动物、浮游动物、藻类等的灭活效果,分析了温度、pH、CT(ClO2浓度×灭活时间)等对ClO2灭活水中微生物效果的影响,探讨了ClO2消毒过程中产生的副产物的性质,提出了相应的控制方法,展望了ClO2在水处理中的应用前景.     

二氧化氯灭活水中隐孢子虫的影响因素及机理研究

以荧光活体染色法研究了ClO2浓度、灭活时间、浊度、pH值、温度、有机物含量等,对ClO2灭活隐孢子虫效果的影响,并利用扫描电镜和蛋白质实验初步探究了灭活机理.结果显示,当pH7.0,水温为25℃,浊度为1NTU时,投加3mg/L ClO2经过120min,可以达到最适消毒效果(存活率小于1%),隐孢子虫的灭活率与ClO2投加浓度、作用时间成非线性正相关.浊度是影响ClO2灭活隐孢子虫的主要因素,浊度越低,灭活效果越佳;水温(较)低,灭活效果稍差;酸性较于碱性更适宜ClO2灭活隐孢子虫;可溶性有机物一定程度上影响ClO2的灭活效果.扫描电镜和蛋白试验表明,ClO2主要破坏其细胞表面结构,从而引起隐孢子虫死亡.     

质子化交联壳聚糖对水中高氯酸根的吸附特性研究

通过合成质子化交联壳聚糖,采用静态试验方法对水中高氯酸根(ClO4-)的吸附效果及机制进行了研究,考察了pH、温度和初始浓度对吸附过程的影响以及吸附剂的重复使用性能.结果表明,质子化交联壳聚糖吸附ClO4-过程属放热反应;当pH在3.0~6.0之间时,对ClO4-均有较好的吸附作用;随着ClO4-初始浓度的增加,吸附容量增加,当初始浓度为100 mg.L-1时,吸附容量在34.39~37.98 mg.g-1之间;当ClO4-为400 mg.L-1时,吸附容量达128.78 mg.g-1.质子化交联壳聚糖对水中ClO4-的吸附过程符合Langmuir和Freundlich等温吸附模型,ClO4-在质子化交联壳聚糖小球上的吸附过程中化学吸附为速率控制步骤.质子化交联壳聚糖小球可在pH为12.8的NaOH溶液中再生,反复使用10次其吸附容量无明显变化,表现出较好的吸附/解吸性能,这为有效地去除水中的ClO4-提供了新的方法.     

无机阴离子对类-Fenton反应的影响

对比研究了4种常见无机阴离子(ClO4-、NO3-、Cl-和SO42-)对类-Fenton 反应中H2O2分解和有机物(莠去津=2.1 μmol·L-1和苯酚=50μmol·L-1)降解的影响.实验在pH=3.00±0.05 (25℃) 条件下完全混合反应器中进行.结果表明,在类-Fenton 反应过程中,ClO4-和NO3- 的存在对H2O2分解和有机物降解几乎没有影响;在不存在有机物条件下,Cl-和SO42- 的加入使得H2O2分解速率显著降低,ClO4-≈NO3- Cl- SO42-;莠去津存在条件下,莠去津降解速率为ClO4-≈NO;C1'SO42-,而H2O2分解速率为ClO4-≈NO3-≈Cl- SO42-;苯酚存在条件下,苯酚和H2O2的降解速率为ClO4-≈NO3-≈SO42- Cl-.无机阴离子对类-Fenton反应的影响一方面是由于Cl-和SO42-与Fe3 发生络合反应,阻碍了Fe3 与H2O2络合物的形成,减少了·OH 的产生;另一方面Cl-和SO42-消耗·OH,形成较低氧化活性的无机自由基(SO4·-和Cl2·-);同时,根据类-Fenton 反应降解有机物的不同,无机阴离子对类-Fenton 反应的影响也有所不同.     

饮用水中卤氧化物离子色谱分析方法研究

直接大体积进样,建立生活饮用水中卤氧化物溴酸盐(BrO3-)、亚氯酸盐(ClO2-)、氯酸盐(ClO3-)含量的离子色谱(IC)法。优化的色谱条件为:Metrosep A Supp 7(250 mm)色谱柱配以Metrosep A Supp1保护柱,淋洗液为3.6 mmol/L Na2CO3与1.0 mmol/L NaHCO3;流速为0.6mL/min;进样量为100μL,抑制型电导检测器。方法结果显示:卤氧化物与常见共存阴离子完全分离,标准曲线在(5.0～400)μg/L范围内具有良好的线性关系(r>0.999),精密度高(相对标准偏差RSD<5.0%),样品加标平均回收率在90.8%~105%之间。按S/N=3,BrO3-、ClO2-、ClO3-的检出限分别为(0.9、0.7、1.0)μg/L。该方法操作简单、分离效果好,可与常见阴离子实现同时分析,灵敏度高,重现性好,适合于饮用水中消毒副产物中溴酸盐、亚氯酸盐、氯酸盐的同时测定。     

Removal effect on Mesocyclops leukarti and mutagenicity with chlorine dioxide

Introduction The eutrophication of surface water is a worldwide problem, which is increasing in significance (Ma and Liu, 2002). Mesocyclops leukarti, a kind of Cyclops, is a waterborne animal that excessively propagates in eutrophic reservoirs and fresh …     

二氧化氯消毒无机消毒副产物控制技术进展研究

日常生活、生产中,饮用水消毒剂受到广泛关注.中国《生活饮用水卫生标准》(GB 5749-2006)规定二氧化氯可作为饮用水消毒剂,但其在消毒过程中所产生的无机消毒副产物,对人类健康存在潜在的危害.随着检测和控制技术水平的发展,对饮用水中无机消毒副产物的研究已成为热点.文章参考大量文献,对饮用水中无机消毒副产物的控制技术进行了详细讨论.     

二氧化氯制备方法研究进展

二氧化氯是一种具有高氧化性和强消毒性的化合物,介绍了二氧化氯制备的化学法、电解法以及电化学法,并对几种工艺方法的优缺点进行了分析和比较,适合工业化生产的工艺主要是化学法中的氯酸钠法和亚氯酸钠法。     

The role of metal oxides on oxidant decay and disinfection byproduct formation in drinking waters: Relevance to distribution systems

Maintaining a residual disinfectant/oxidant (e.g., chlorine and chlorine dioxide), is a generally used strategy to control microbial contaminants and bacterial regrowth in distribution systems. Secondarily oxidant, such as hypobromous acid (HOBr), can be formed during chlorination of bromide-containing waters. The decay of oxidants and formation of disinfection byproducts (DBPs) due to the interaction between oxidants and selected metal oxides were studied. Selected metal oxides generally enhanced the decay of these halogen-containing oxidants via three pathways: (1) catalytic disproportionation to yield an oxidized form of halogen (i.e., halate) and reduced form (halide for chlorine and bromine or chlorite for chlorine dioxide), (2) oxygen formation, and (3) oxidation of a metal in a reduced form (e.g., cuprous oxide) to a higher oxidation state. Cupric oxide (CuO) and nickel oxide (NiO) showed significantly strong abilities for the first pathway, and oxygen formation was a side reaction. Cuprous oxide can react with oxidants via the third pathway, while goethite was not involved in these reactions. The ability of CuO on catalytic disproportionation of HOBr remained stable up to four cycles. In chlorination process, bromate formation tends to be important (exceeding 10 µg/L) when initial bromide concentration is above 400 µg/L in the presence of dissolved organic matter. Increasing initial bromide concentrations increased the formation of DBPs and calculated cytotoxicity, and the maximum was observed at pH 8.6 during chlorination process. Therefore, the possible disinfectant loss and DBP formation should be carefully considered in drinking water distribution systems.     

Removal of benzene homologous compounds with chlorine dioxide

Ｒｅｍｏｖａｌｏｆｂｅｎｚｅｎｅｈｏｍｏｌｏｇｏｕｓｃｏｍｐｏｕｎｄｓｗｉｔｈｃｈｌｏｒｉｎｅｄｉｏｘｉｄｅ￥ＣｈｅｎＨｕｉ；ＷｅｉＤｏｎｇｂｉｎ（ＣｈｅｍｉｓｔｒｙＤｅｐａｒｔｍｅｎｔ，ＮｏｒｔｈｗｅｓｔＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｌａｎｚｈ...     

Full-scale study of removal effect on Cyclops of zooplankton with chlorine dioxide

Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation. In this paper, a full-scale study of chlorine dioxide preoxidation cooperating with routine clarification process for Cyclops removal was conducted in a waterworks. The experimental results were compared with that of the existing prechlorination process in several aspects: including the Cyclops removal efficiencies of water samples taken from the outlets of sedimentation tank and sand filter and the security of drinking water and so on. The results showed that chlorine dioxide might be more effective to inactivate Cyclops than chlorine and Cyclops could be thoroughly removed from water by pre-dosing chlorine dioxide process. The GC-MS examination and Ames test further showed that the sort and amount of organic substance in the treated water by chlorine dioxide preoxidation were evidently less than that of prechlorination and the mutagenicity of drinking water treated by pre-dosing chlorine dioxide was substantially reduced compared with prechlorination.     

新型消毒剂二氧化氯的开发与应用

从保护饮用水的安全与卫生出发，介绍了替代液氯和其它氯制品的新型消毒剂——二氧化氯所具有的优点，特别是可有效抑制三卤代烷（ＴＨＭＳ）的产生；讨论了二氧化氯的最佳投放方式及ＣｌＯ－２和ＣｌＯ－３等有害副产物生成的机理和控制方法     

自来水厂液氯贮罐氯气泄漏事故风险评价初探

针对自来水厂液氯贮罐发生泄露的事故风险,应用烟团模式进行了液氯泄露后污染物浓度预测,并根据预测浓度从环境标准和化学物质危险度两方面进行了事故风险评价探讨,得出致死风险.     

Pilot-scale study of removal effect on Chironomid larvae with chlorine dioxide

Introduction C hironom id, from the dipteran fam ily Chirono- m idae, is a non-biting m idge that is w idely distributed in the northern hem isphere at tem perate latitudes. C hironom id larvae can be found both in lentic and lotic environm ents, usually …     

Impact of combining chlorine dioxide and chlorine on DBP formation in simulated indoor swimming pools

The main objective of this study was to assess the combined use of chlorine dioxide (ClO2) and chlorine (Cl2) on the speciation and kinetics of disinfection by-product (DBP) formation in swimming pools using synthetic pool waters prepared with a body fluid analog (BFA) and/or fresh natural water. At 1:25 (mass ratio) of ClO2 to Cl2, there was no significant reduction in the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) for both BFA solution and natural water compared to the application of Cl2 alone. When the mass ratio of ClO2 to Cl2 increased to 1:1, substantial decreases in both THMs and HAAs were observed in the natural water, while there was almost no change of DBP formations in the BFA solution. Haloacetonitriles and halonitromethanes levels in both water matrices remained similar. In the presence of bromide, the overall DBP formation increased in both BFA solution and natural water. For the DBP formation kinetics, after 72 hr of contact time, very low formation of THMs and HAAs was observed for the use of ClO2 only. Compared to Cl2 control, however, applying the 1:1 mixture of ClO2/Cl2 reduced THMs by > 60% and HAAs by > 50%. Chlorite was maintained below 1.0 mg/L, while the formation of chlorate significantly increased over the reaction time. Finally, in a bench-scale indoor pool experiment, applying ClO2 and Cl2 simultaneously produced less THMs compared to Cl2 control and kept chlorite at < 0.4 mg/L, while HAAs and chlorate accumulated over 4-week operation period.