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961.
An overview of the methods used in the characterisation of natural organic matter (NOM) in relation to drinking water treatment 总被引:9,自引:0,他引:9
Matilainen A Gjessing ET Lahtinen T Hed L Bhatnagar A Sillanpää M 《Chemosphere》2011,83(11):1431-1442
Natural organic matter (NOM) is found in all surface, ground and soil waters. During recent decades, reports worldwide show a continuing increase in the color and NOM of the surface water, which has an adverse affect on drinking water purification. For several practical and hygienic reasons, the presence of NOM is undesirable in drinking water. Various technologies have been proposed for NOM removal with varying degrees of success. The properties and amount of NOM, however, can significantly affect the process efficiency. In order to improve and optimise these processes, the characterisation and quantification of NOM at different purification and treatment processes stages is important. It is also important to be able to understand and predict the reactivity of NOM or its fractions in different steps of the treatment. Methods used in the characterisation of NOM include resin adsorption, size exclusion chromatography (SEC), nuclear magnetic resonance (NMR) spectroscopy, and fluorescence spectroscopy. The amount of NOM in water has been predicted with parameters including UV-Vis, total organic carbon (TOC), and specific UV-absorbance (SUVA). Recently, methods by which NOM structures can be more precisely determined have been developed; pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), multidimensional NMR techniques, and Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). The present review focuses on the methods used for characterisation and quantification of NOM in relation to drinking water treatment. 相似文献
962.
963.
Sulfamethoxazole sorption by sediment fractions in comparison to pyrene and bisphenol A 总被引:5,自引:0,他引:5
Juan Hou Xuekui Niu Baoshan Xing 《Environmental pollution (Barking, Essex : 1987)》2010,158(9):2826-2832
The environmental behavior of antibiotics has attracted great research attention. However, their sorption mechanisms in soils/sediments are still unknown. Comparison of the sorption properties between the widely-studied hydrophobic organic contaminants (HOCs) and antibiotics may provide valuable insight to antibiotic sorption mechanisms. Thus, in this study batch experiments for pyrene (PYR), bisphenol A (BPA), and sulfamethoxazole (SMX) sorption were conducted on a sediment sample and its separated fractions. Our results showed the high sorption of PYR on black carbon and organic matter. Although high sorption of SMX was observed for both separated organic fractions (humic acids) and inorganic mineral particles, the original sediment particles showed relatively low sorption. Competitive sorption between SMX and dissolved humic acid on mineral particles was observed in this study. This competitive interaction is a unique process for antibiotic sorption in soils/sediments compared with apolar HOCs and may be one of the important factors controlling the antibiotic sorption. 相似文献
964.
研究以超高盐榨菜腌制废水为对象,考察填料种类、负荷和温度对ASBBR启动及处理效能的影响。研究结果表明,在温度为30℃,盐度为7%(NaCl计),负荷为1 kg COD/(m3·d)的条件下,采用聚氨酯泡沫填料的反应器经67 d可成功构建超高盐榨菜腌制废水厌氧生物处理系统,较未设置填料、投加半软性组合填料、球形组合填料和聚苯乙烯泡沫填料的反应器分别缩短了26、6、24和18 d,且运行至第79天,可使出水COD降至375 mg/L,COD去除率为92.86%;通过对负荷的阶段逐步提高,可提升反应器有机负荷至15 kg COD/(m3·d),使进水COD为(27 000±2 000)mg/L的超高盐废水,出水COD均值降至2 200 mg/L ,平均去除率达到92.03%;温度对反应器处理效能影响显著,温度分别为30、25、20、15和10℃时,反应器COD去除率分别为92.63%、84.07%、67.13%、54.61%和44.19%。 相似文献
965.
沈阳市固定燃烧源挥发性有机化合物2007年排放清单研究 总被引:1,自引:0,他引:1
挥发性有机化合物(VOCs)与.OH的反应是对流层臭氧形成的重要化学过程,是导致城市光化学烟雾的根本原因。为建立沈阳市固定燃烧源VOCs排放清单,选取了电力热力行业、钢铁行业和秸秆燃烧3个主要排放源进行研究。结果表明:(1)2007年,沈阳市固定燃烧源VOCs排放总量为8 544.539 t,其中排放量最大的是秸秆燃烧,为6 317.115 t;其次是电力热力行业,为2 225.780 t;最小的是钢铁行业,为1.644 t。(2)沈阳市各区县固定燃烧源VOCs排放量由大到小排序依次为新民市、法库县、东陵区、康平县、辽中县、于洪区、苏家屯区、大东区、沈北新区、铁西区、沈河区、皇姑区、和平区;VOCs排放强度由大到小排序依次为大东区、沈河区、铁西区、东陵区、皇姑区、和平区、于洪区、苏家屯区、法库县、康平县、辽中县、沈北新区、新民市。 相似文献
966.
以有机固体废弃物 (废棉絮、废纸 )为原料 ,在管式炉热解反应器热解生产脱水内醚糖。研究了热解温度对热解产物相态分布的影响。同时 ,利用HPLC对脱水内醚糖的产量进行了测定。HPLC分析结果表明 :热解液水相中主要化学物质是乙酸 ,而非水相中主要化学物质是脱水内醚糖 相似文献
967.
Ahde El Imache Sylvie Dousset Ahmed Satrallah Abdelmalek Dahchour 《Journal of environmental science and health. Part. B》2013,48(3):161-167
The Gharb region in Morocco is an important agricultural zone where soils receive pesticide treatments and organic amendments to increase yields. The groundwater aquifer in the Gharb region is relatively shallow and thus vulnerable. The objective of this work was to study the influence of organic amendments on diuron, cyhalofop-butyl and procymidone leaching through undisturbed soil columns. Two soils were sampled from the Gharb region, a Dehs (sandy soil) and a R’mel (loamy clay soil). Following elution (124.5 mm), the amount of pesticide residues in the leachates of the sandy soil (0.06–0.21 %) was lower than in those of the loamy clay soil (0.20–0.36 %), which was probably due to preferential flow through the loamy clay soil. The amount of procymidone leached through the amended soil columns was greater than the control for the sandy soil only. The organic amendments did not significantly influence diuron and cyhalofop-butyl leaching in either of the soils. The application of organic amendments affected the amounts of dissolved organic matter (DOM) eluted and thus pesticide leaching as a function of soil-type. Nevertheless, in some case, the formation of pesticide-DOM complexes appeared to promote pesticide leaching, thus increasing groundwater contamination risks. 相似文献
968.
969.
970.
摇动床生物膜反应器和活性污泥法组合技术处理高浓度有机废水的研究 总被引:1,自引:1,他引:1
利用摇动床生物膜反应器(简称摇动床)技术具有的容积负荷高与污泥产量低的优点,在普通活性污泥池的前部填充高性能丙烯酸树脂纤维(Biofringe)填料,研究了摇动床和活性污泥法组合技术处理高浓度有机废水的有效性。结果表明,该组合技术具有很强的有机物去除能力,当进水COD平均质量浓度由1500mg/L上升到2514mg/L时,出水COD的平均去除率基本保持在96%以上;整个运行阶段的出水COD浓度均满足《污水综合排放标准》(GB8978—1996)的二级标准;当进水NH4+-N浓度增加时,NH4+-N的去除率由99.7%降低到76.5%,但是在试验运行的整个阶段,摇动床和活性污泥法组合技术系统都表现出较强的硝化能力;活性污泥池中最高的混合液悬浮固体(MLSS)质量浓度为10625mg/L,最高MLSS约为普通活性污泥法的4倍;运行结束后的污泥产率为0.186,污泥产率仅为普通活性污泥法的50%左右。 相似文献