粉末活性炭与单壁碳纳米管对水中多氯联苯的吸附

多氯联苯(PCBs)有较强的憎水性,在水中的溶解度很小,主要以与天然有机物结合,或附着于颗粒物的形式存在。粉末活性炭(PAC)和单壁碳纳米管(SWCNTs)对非极性较强的有机物有较好的吸附去除效果。通过研究粉末活性炭和单壁碳纳米管表面的物理化学性质,并对比研究二者对水中多氯联苯的吸附效能,包括吸附动力学和吸附等温线以及对实验数据进行相应的吸附模型拟合可知,粉末活性炭和碳纳米管对PCBs均有较好的吸附效果。10 min时粉末活性炭对多氯联苯的吸附量可达平衡吸附量的75%以上;40 min时可达90%以上;100 min以后吸附基本达到平衡。10 min时单壁碳纳米管对多氯联苯的吸附量可达平衡吸附量的60%以上,40 min时可达90%以上,80 min以后吸附基本达到平衡。     

饮用水处理中颗粒物数量变化及粒径分布规律

结合水厂实际水处理工艺及活性炭深度处理装置,试验研究砂滤池和活性炭滤柱出水中颗粒物数量变化及粒径分布规律.试验结果表明,过滤周期内砂滤池出水中颗粒物总数平均为148个/mL,其中粒径大于2μm颗粒物的数量平均为27个/mL,其粒径主要分布在2~15μm之间.砂滤池初滤水中粒径大于2μm颗粒物含量较高,前10 min内其数量高于50个/mL.砂滤池出水的浊度变化滞后于颗粒物数量变化,且二者之间的相关性差(R2<0.1).与砂滤池出水(164个/mL)相比,活性炭滤柱出水中颗粒物数量水平(561个/mL)显著提高,其中粒径大于2μm颗粒物数量达153个/mL,出水中粒径在2μm和2~7μm之间的颗粒物数量增多最为明显.     

饮用水处理中有机物分子量分布规律

为了对不同水源水以针对性的强化工艺提高有机物去除率,以超滤膜法分析了长江下游段水源水经常规工艺及活性炭处理出水中溶解性有机物(DOC)的分子量(MW)分布,以有各工艺单元对有机物的去除效应.结果表明:长江水源水以小分子量的有机物为主(小于10 k Dalton的有机物占64.40%);常规工艺对大分子量有机物去除率很高,尤其对MV为10 k Dalton以上的有机物去除率达67%以上,但对小分子量有机物去除率很低.常规工艺对Mw为1～10 k Dalton的有机物去除率仅为28%,而MW小于1 k Dalton的有机物反而增加了30%左右.经活性炭处理后,MW小于1 k Dalton的有机物去除率达84%;出水UV254值及SUVA值比滤后水分别下降25%和10%.     

活性炭对天然水中痕量有机物的吸附模型的建立

考虑到天然水中实际存在的痕量有机物要比以腐殖质为主的天然有机物(NOM)的量小很多,有可能存在理想吸附现象。将在此条件下对理想吸附溶液理论(IAST)进行简化,推导出理想吸附模型,该模型对研究活性炭对水中微污染物吸附规律有非常重要的指导意义。     

用于电厂生活污水深度处理的不同臭氧化工艺

以河北西柏坡电厂生活污水处理厂二级出水为原水,考察了不同臭氧化工艺对该厂二级出水中微量有机物的处理效果.静态实验和动态实验的结果均表明,紫外线、活性炭协同催化臭氧化技术(即OUC技术)可显著提高二级出水中难降解有机物的氧化降解,并可显著提高臭氧利用率.     

混凝/吸附预处理对超滤膜过滤特性的影响

采用混凝和吸附两种方法预处理模拟微污染地表水,研究了不同水样的污染物指标与超滤膜污染的关系,分析了颗粒物特性对超滤膜通量的影响. 试验结果表明:粉末活性炭吸附能够有效降低水中有机物浓度,但是对于浊度去除效果不明显;混凝对于有机物去除效果较差,但能明显降低水中浊度. 混凝预处理能够有效提高膜通量,但吸附对膜通量没有影响. 不同水样的膜污染指数与浊度及溶解性有机物（DOC）的相关性拟合表明,膜污染指数与浊度性相关性较好,与DOC相关性较差,水中浊度物质是试验条件下膜污染的主要物质;0.01~1.20μm的胶体和颗粒物是造成膜通量下降的主要因素,同时,浊度物质造成的膜污染指数具有良好的累积性.      

PAC及颗粒物对超滤膜有机物污染的影响

为了研究粉末活性炭(PAC)及水中颗粒物对浸没式中空纤维超滤膜有机物污染的影响特性,分别采用单独超滤和PAC-超滤工艺处理含不同污染物的原水,分析其膜比通量和跨膜压差的变化。结果发现:与单独超滤清水相比,投加25 mg/L和100 mg/L的PAC后,稳定运行的膜比通量分别下降了0.06和0.14 L/(h.m2.kPa)。与单独超滤天然有机物污染原水相比,投加20、50、100 mg/L的PAC时的跨膜压差增长速率分别下降了0.003 1、0.002 3、0.001 7kPa/min。天然有机物原水中投加高岭土后经单独超滤和PAC-超滤工艺处理,水力反洗后的归一化膜比通量与投加前相比,分别平均提高了5%和2.6%。     

生化出水中各类有机污染物的特性及在混凝处理过程中的行为

以城市生活污水厂二级生化出水为研究对象,考察了生化出水中有机污染物中各组分含量、分子量分布特点等特性,以及各类有机物在三氯化铁混凝处理过程中的行为.实验结果表明:当生化出水中有机物浓度以DOC表征时,水中疏水性物质与亲水性物质各占50%,其中疏水酸浓度最高,约为42%,其次为亲水酸和非酸亲水物质,分别占26%和24%,非酸疏水物质仅为8%.其中疏水酸中的不饱和双键或芳香环有机物的含量较高.二级生化出水中的DOC主要集中在分子量大于10 000 D的有机物,占48.8%.在三氯化铁混凝过程中,能去除几乎所有的大分子量有机物以及大部分芳香族有机物(61%的UV254),对小分子、亲水性有机物基本没有去除效果.因此,混凝法需与其他能去除亲水性、小分子量有机物(＜3 000 D)的处理工艺结合,以进一步提高有机物的去除效率.     

以SPE作为UV法测定硝酸盐氮的预处理方法

针对水样中有机物和浊度严重干扰紫外分光光度法测定硝酸盐氮的问题,分析了ENVI-18,LC-8,HLB(亲水亲油平衡)和自制PAC(粉末活性炭)四种固相萃取柱对水样中有机物和浊度等干扰的消除效果.研究结果显示:当进水水样DOC质量浓度为4mg/L时,自制PAC固相萃取柱和LC-8型固相萃取柱对水样中有机物的保留率均大于99.5%,而HLB和ENVI-18型固相萃取柱对有机物的保留率低于6.75%.ENVI-18和LC-8柱对水中硝酸盐氮不具有保留效果也不会向水中释放干扰硝酸盐氮的物质,PAC柱对水中硝酸盐氮具有强烈的保留作用,HLB柱则会向水中释放少量的干扰硝酸盐氮测定的物质.优选LC-8型固相萃取柱作为预处理小柱,并在宜兴西氿水上进行了应用,结果显示:加标回收率为94.0%~97.0%,相对标准偏差为3.14%.每支规格为500mg/3mL的LC-8型固相萃取柱能保留水中约0.75mg有机物(以DOC计),可处理10~15个水样,使用后的固相萃取柱可采用甲醇再生后再次使用.     

组合型生态浮床中有机物及氮的去除转化

通过设置水生植物浮床A、植物介质浮床B及植物介质河蚌浮床(组合型生态浮床)C等3个不同层次配置的浮床,考察了同样的运行条件下,各浮床出水中不同形态的有机物及氮的质量浓度变化,分析了浮床中各配置对有机物及氮的去除转化规律,同时研究了三角帆蚌对人工介质微生物富集特性的影响.结果表明:人工介质对溶解性的有机物及氮起到了明显的去除作用,三角帆蚌通过滤食消化促进了有机颗粒物的可溶化和无机化,对氮形态的转化起到了重要作用,从而提高了组合型生态浮床对氮的去除效果;三角帆蚌的引入增强了单位人工介质上微生物的TTC-脱氢酶活性与硝化细菌密度,从另一角度阐明了三角帆蚌对有机物及氮去除转化促进的特性.     

上流式生物活性炭滤池沿程TTC-DHA生物活性的研究

采用上流式生物活性炭滤池（UBACF）深度处理纺织废水，讨论了滤池内附着生物膜的测定方法，研究了滤池沿程截留生物膜与附着生物膜活性的大小与变化规律。通过TTC-DHA活性实验检测到生物活性炭BAC经脱膜后炭粒存在对脱氢酶的吸附，吸附量同生物膜的总活性大小与活性炭自身的吸附性能强弱有关。活性炭粒吸附有利于提高滤池内的生物活性，特别是炭粒表面生物膜遭到破坏后，炭粒吸附功能有助于保留部分生物活性。研究发现UBACF顶部的BAC同样存在较高活性，利于滤池内难处理有机物的生物降解去除。     

Evidence for non-selective preservation of organic matter in sinking marine particles

The sinking of particulate organic matter from ocean surface waters transports carbon to the ocean interior, where almost all is then recycled. The unrecycled fraction of this organic matter can become buried in ocean sediments, thus sequestering carbon and so influencing atmospheric carbon dioxide concentrations. The processes controlling the extensive biodegradation of sinking particles remain unclear, partly because of the difficulty in resolving the composition of the residual organic matter at depth with existing chromatographic techniques. Here, using solid-state 13C NMR spectroscopy, we characterize the chemical structure of organic carbon in both surface plankton and sinking particulate matter from the Pacific Ocean and the Arabian Sea. We found that minimal changes occur in bulk organic composition, despite extensive (>98%) biodegradation, and that amino-acid-like material predominates throughout the water column in both regions. The compositional similarity between phytoplankton biomass and the small remnant of organic matter reaching the ocean interior indicates that the formation of unusual biochemicals, either by chemical recombination or microbial biosynthesis, is not the main process controlling the preservation of particulate organic carbon within the water column at these two sites. We suggest instead that organic matter might be protected from degradation by the inorganic matrix of sinking particles.     

Photochemical alteration of biogenic particles in wastewater effluents

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.     

纳米Al(OH)3干法表面改性及其在EVA中的应用

研究了钛酸酯偶联剂T对纳米Al(OH)₃的干法改性工艺，确定了偶联剂最佳质量分数0.5%、改性时间25min、改性温度100～110℃。采用红外光谱、TEM等检测手段对改性结果进行表征，改性后无机粉体表面包覆有机基团，吸油值减小，团聚减弱，比表面积增加。改性Al(OH)₃在乙烯-醋酸乙烯共聚物(EVA)中具有良好的分散性，阻燃效能提高，并保持了材料的力学性能。     

Pilot Study on Nanofiltration Combined with Ozonation and GAC for Advanced Drinking Water Treatment

IntroductionThe conventional process for surface water treatment,which consists of flocculation, sedimentation and filtrationcurrently, had been applied inproducingdrinkingwater formany years. Although this process can remove turbidityand bacteria in surface water effectively, only about from20% to 30% of natural organic matter ( NOM) can beeliminated. When the purified water is disinfected bychlorination, these NOMs may react with chlorine. As aresult some dis…     

泥质烃源岩密度分组及有机质赋存类型初探

选取济阳坳陷沙河街组深湖相暗色泥岩为研究对象,通过不同密度ZnBr2重液浮选,将样品分离成多个密度组分,对各组分检测透射光、荧光、X光衍射等,揭示不同组分有机质赋存类型的差异性.分析结果表明,①组分(密度ρ<1.6g.cm-3)以颗粒有机质为主,有机质与矿物无明显紧密结合关系;②,③组分(1.6g.cm-3<ρ<2.2g.cm-3,ρ>2.2g.cm-3)多见无定形有机质分散于细粒矿物相中,呈橙黄-亮黄色荧光,反映有机质与矿物颗粒紧密共生的赋存特征.进一步对不同密度组分有机质分配的研究表明,①组分结合了烃源岩总有机质质量不到1%;②,③组分结合了烃源岩中90%以上质量的有机质.这反映了有机质和矿物颗粒共生的赋存形式在有机质保存中不可忽视的重要地位.     

Enriched Oxygen BAC Method in Advanced Treatment of Textile Dyeing-printing & Alkali-peeling Wastewater

IntroductionWith increasing application of polyester deweightingtechniques in Chinese textile plants , a great deal of alkali-peeling waste streams containing high strength recalcitrantorganic matters and waste alkali are discharged . Thesealkali-peeling waste streams are normally mixly treated withdying-printing wastewater by physi-chemical pretreat mentcombined with anaerobic-aerobic bio-treat ment processes .But effluents emitted by most textile plants in China areal ways beyond dischargin…     

白鲢(Hypophthalmichthys molitrix Cuvier et Valencienns)对常州市主要工业废水及部分有机毒物的回避反应

本文研究了白鲢对常州市四种主要工业废水及四种有机毒物的回避反应,其回避能力随废水及主要有机毒物的种类、浓度的不同而异,并与浓度成正相关。试验结果表明,白鲢能回避0.28％和1.12％染料废水;2.5％、5.0％和10.0％石油化工废水;4.5％和9.0％印染废水;6％、12％和24％化工厂有机废水。也能同避0.80mg/lα-硝基苯;1.25mg/l和5.00mg/l间硝基苯胺;4.0mg/l间—二硝基苯;4.0mg/l磷酸三丁酯。     

Self-organization of dissolved organic matter to micelle-like microparticles in river water

In aquatic systems, the concept of the 'microbial loop' is invoked to describe the conversion of dissolved organic matter to particulate organic matter by bacteria. This process mediates the transfer of energy and matter from dissolved organic matter to higher trophic levels, and therefore controls (together with primary production) the productivity of aquatic systems. Here we report experiments on laboratory incubations of sterile filtered river water in which we find that up to 25% of the dissolved organic carbon (DOC) aggregates abiotically to particles of diameter 0.4-0.8 micrometres, at rates similar to bacterial growth. Diffusion drives aggregation of low- to high-molecular-mass DOC and further to larger micelle-like microparticles. The chemical composition of these microparticles suggests their potential use as food by planktonic bacterivores. This pathway is apparent from differences in the stable carbon isotope compositions of picoplankton and the microparticles. A large fraction of dissolved organic matter might therefore be channelled through microparticles directly to higher trophic levels--bypassing the microbial loop--suggesting that current concepts of carbon conversion in aquatic systems require revision.