厕所污水回用脱色方法及机理研究

采用投加粉末活性炭对经膜生物反应器处理的厕所回用水（膜出水）进行脱色.对厕所回用水中色度物质的成分及分子量分布,对选定高效适用的活性炭及活性炭对厕所回用水中色度物质的去除机理进行了探讨.试验结果表明,使膜出水显色的物质是一类在紫外区有明显吸收或有特征吸收峰的有机物,且大部分物质分子量分布在6～60 KD的范围内.在选定有高效脱色效果的活性炭时,要综合考虑活性炭的亚甲基蓝吸附值和焦糖脱色率2个指标,其中焦糖脱色率有着更重要的意义.厕所回用水脱色是对其各个分子量区间颜色物质去除效果的总和.     

印染废水生化出水中各类有机物在小型活性炭床吸附过程中的去除效果

采用连续流活性炭炭床处理印染废水生化出水,通过XAD-8/XAD-4吸附树脂将印染废水生化出水中的溶解性有机物分为4类:疏水酸、非酸疏水物质、弱疏水物质和亲水物质,采用超滤膜法测定水样的分子量分布,对印染废水生化出水中不同种类以及不同分子量大小的有机物在煤质炭、椰壳炭2种活性炭动态实验处理过程中的去除特性进行研究。实验结果表明,2种活性炭对该水样中的有机物均有明显的去除效果,其中以煤质炭的处理效果较优。煤质炭吸附疏水性和亲水性有机物均有明显的处理效果,对非酸疏水物质和弱疏水有机物的吸附效果较差。煤质炭对分子量<10 k的小分子有机物的吸附效果对实验结果的贡献较大。     

造纸中段废水的混凝-臭氧氧化深度处理研究

就混凝-臭氧氧化组合工艺对造纸中段废水生物处理出水的净化效果进行了研究.结果表明,Ca(OH)2对废水色度、TOC、COD和254 nm的紫外吸收值(UV254)的去除效果均优于聚合氯化铝/聚丙烯酰胺(PAC/PAM);Ca(OH)2-O3组合工艺的处理效果也优于PAC/PAM-O3工艺.当Ca(OH)2投加量为1 g/L、臭氧投加量为50 mg/L时,废水色度降低至10倍以下,COD小于150 mg/L.经Ca(OH)2混凝处理后,相对分子量在0.5～1.0 ku和10.0 ku以上的有机物显著减少;进一步臭氧氧化处理后,除0.5 ～1.0 ku范围的有机物大幅度增加外,其余分子量有机物显著减少.由于对色度贡献很大的大分子量物质的去除,废水的色度显著下降直至无色.     

不同深度处理工艺去除污水处理厂出水中氮磷的比较研究

城市污水厂出水直接进入天然水体、或经过深度处理后回用于灌溉、补充景观水体和回灌地下水,均需要进行安全性评价.针对北京市北小河污水处理厂出水经过深度处理后回用于奥运公园的安全性,比较了不同深度处理工艺对营养盐(氮、磷)总量和不同形态的去除效果.研究表明,二级处理本身对氮磷的去除效果十分有限,回用水需经过深度处理.在所研究的生物活性炭吸附、微滤、超滤、反渗透以及上述技术的组合工艺中,使用超滤和反渗透联用的工艺路线对脱氮除磷的效果较为理想,其他工艺对去除氮磷的效果十分有限.     

不同深度处理工艺去除污水处理厂出水中氮磷的比较研究

城市污水厂出水直接进入天然水体、或经过深度处理后回用于灌溉、补充景观水体和回灌地下水,均需要进行安全性评价.针对北京市北小河污水处理厂出水经过深度处理后回用于奥运公园的安全性,比较了不同深度处理工艺对营养盐（氮、磷）总量和不同形态的去除效果.研究表明,二级处理本身对氮磷的去除效果十分有限,回用水需经过深度处理.在所研究的生物活性炭吸附、微滤、超滤、反渗透以及上述技术的组合工艺中,使用超滤和反渗透联用的工艺路线对脱氮除磷的效果较为理想,其他工艺对去除氮磷的效果十分有限.     

低温下膜-生物活性炭工艺深度处理回用水的试验研究

开展低温下膜-生物活性炭工艺深度处理回用水的试验研究，探讨该工艺低温运行的可行性及作用机制。结果表明，采用HRT为3h的膜-生物活性炭反应器对回用水中有机物具有良好的去除效果，CODcr，UV254、UV410的去除率分别稳定在33％、35％、40％；对NH3-N的去除效果不明显，其平均去除率在15％左右，主要受原水浓度过高的影响。同时与其他工艺进行对比研究，结果表明，由于该工艺结合了膜分离、活性炭吸附、生物降解三者的综合作用而表现出明显的优势。     

高效混凝-膜生物反应器工艺处理印染废水的研究

利用自制的高效廉价混凝剂,结合仿生膜生物反应器技术对印染废水的处理进行了研究。试验得到：混凝后CODcr的去除率平均达75．1％,色度分别从1250倍和390倍降为30倍和12倍．透过率达到84．6％和86．2％,浊度在10度以下。再经仿生膜生物反应器处理,出水CODcr低于50mg／L,CODcr、,去除率为96．2％,出水无色无味,达到部分回用水标准。     

城市污水厂二级处理出水深度处理组合工艺研究

为了研究臭氧-曝气生物滤池二级处理出水深度处理组合工艺的处理效果，采用臭氧-曝气生物滤池(biological aerated filter， BAF)组合工艺对城市污水处理厂二级生化处理出水进行深度处理。结果表明，组合工艺对造成水中色度的主要物质腐植酸和富里酸类有机物和嗅味物质中的二甲基三硫和二甲基异莰醇(MIB)能够进行有效去除。臭氧氧化能够显著提高后续BAF单元对COD_Mn的去除。在进水COD_Mn6~8 mg/L、色度为25~30度、浊度约为8 NTU的条件下，当臭氧投加量为5~6 mg/L、BAF的水力停留时间为1~1.5 h时，出水COD_Mn< 5 mg/L、色度<5度、浊度<1 NTU，出水水质可满足生产工艺对回用水的水质要求。     

新型净水材料的吸附特性研究

采用高效液相色谱分析微污染水原水、新型材料吸附后出水及活性炭吸附后出水的特征，对比新型材料及活性炭对微污染水中不同分子量的有机物的吸附效果，以此间接反映两种材料的孔径分布特点，分析两种材料的不同吸附特性，并讨论新型净水材料的吸附机理。     

生物活性炭法深度处理印染废水及其生物毒性的表征

采用负载经驯化后微生物的活性炭深度处理实际印染废水,研究生物活性炭系统中存在的生物相及其降解有机污染物的作用,并表征了处理后印染废水的生物毒性.结果表明,生物相中含有草履虫、轮虫及钟虫等原生动物.随着运行次数的增加,活性炭反应器在运行5次后出水的COD、NH3-N及色度去除率骤降,但是生物活性炭处理后出水的COD、NH3-N及色度去除率缓慢下降.生物活性炭能很好地降解印染废水中的苯酚类和稠环芳烃污染物.本研究中生物活性炭反应器对氨氮和COD的去除符合一级动力学方程,去除动力学常数分别为1.02和0.96.经过生物活性炭的处理可以将印染废水的生物毒性降到适于小球藻生长的水平.     

不同工艺对含高浓度腐殖酸地下水处理的可行性

针对内蒙古农村地区高腐殖酸地下水的处理问题，分别对（pH调节）-PAC强化混凝、高锰酸钾预氧化／混凝、活性炭吸附／混凝、Fenton氧化等技术处理的可行性进行了研究，同时利用三维荧光和高效体积排阻色谱分析处理前后水中有机物的组成变化特征。有机分析结果显示，水中的有机物为腐殖酸类物质，分子量分别为1600和3500，腐殖酸类物质为水中色度的主要贡献者。原水PAC强化混凝、高锰酸钾预氧化／PAC混凝对有机物的去除效果不佳，处理前后水样DOC浓度无明显变化，而pH调节．PAC强化混凝、微米活性炭吸附和Fenton氧化均能有效去除有机物。将原水pH调节至6．5，经300mg／LPAC混凝后出水DOC降至5．99mg／L。活性炭投加量为0．6g／L时，DOC降至7．6mg／L，然后采用60mg／LPAC混凝出去高度分散而不易沉降的小颗粒活性炭。此外，当反应初始pH值为3，过氧化氢投加量为0．5％（v／v），亚铁和双氧水摩尔比为0．05时，出水DOC降至5．6mg／L，氧化后有小分子有机物生成。     

给水曝气生物滤池内置粉末活性炭复合净水效果的研究

在给水曝气生物滤池内置粉末活性炭,对比分析其对各工艺单元水质净化效果的影响,确定给水曝气生物滤池内置粉末活性炭的作用与最佳投加量,研究表明,给水曝气生物滤池将活性炭截留在滤池内,大幅度提高了粉末活性炭利用率,部分未饱和粉末活性炭通过反冲洗排入后续常规处理系统,作为生物载体仍能够进一步发挥生物强化作用。当粉末活性炭的投加量为8 mg/L时,砂滤出水氨氮、CODMn、浊度和色度均值分别为：0.02 mg/L,1.82 mg/L0,.46 NTU和6度,去除率分别达到99.6%、71.2%、99.1%和80.6%,出水指标达到《生活饮用水卫生标准（》GB5749-2006）和《饮用净水水质标准（》CJ94-2005）规定的标准。与常规工艺相比,投加量降低了20%～60%。     

聚合氯化铝与粉末活性炭联合强化混凝处理垃圾渗滤液

研究了联合粉末活性炭与聚合氯化铝(PAC)强化混凝对垃圾渗滤液原水的处理效果。结果表明,在原水COD为4 100 mg/L、浊度为147 NTU、UV254为20的条件下,粉末活性炭的加入可以有效增加垃圾渗滤液中有机物的去除率,PAC投加量为0.6 g/L时,投加0.6 g/L粉末活性炭,COD的去除率由21.6%提高到29.1%,UV254去除率由29.8%提高到39.9%,剩余浊度由138 NTU降到133 NTU。该强化混凝过程使原水中溶解性小分子有机物的去除率提高显著,PAC投加量为0.6 g/L时,投加0.6 g/L粉末活性炭,在分子量小于1 kDa的范围内,UV254去除率由2.9%上升为10%。     

Adsorption capacity of powdered activated carbon for 3,5-dichlorophenol in activated sludge

The objectives of this study were to evaluate the performance of powdered activated carbon treatment (PACT) process based on the adsorption capacity of powdered activated carbon (PAC) in activated sludge and the effect of dissolved organic substances in activated sludge on the adsorption capacity of PAC. The DCP adsorption capacity of three PACs originated from different raw materials (coal, soft coal and sawdust) in activated sludge were 29%, 34% and 17% of that of new PAC, respectively. The performance of PACT process for shock loading of 3,5-dichlorophenol (3,5-DCP) was different among PACs in spite of the same adsorption capacity in new PAC. The performance of PACT process for removal of DCP is dependent not on the adsorption capacity of new PAC but on the adsorption capacity of PAC in the aeration tank. Dissolved organic matter (DOM) with molecular weight smaller than 50kDa did not affect the adsorption capacity of PAC for 3,5-DCP in the activated sludge reactor. DOM with molecular weight larger than 50kDa and biofilm developed on the surface of PAC seemed to be responsible for the decreased adsorption capacity of PAC for the DCP.     

Determination of the adsorptive capacity and adsorption isotherm of vapor-phase mercury chloride on powdered activated carbon using thermogravimetric analysis

This study investigated the use of thermogravimetric analysis (TGA) to determine the adsorptive capacity and adsorption isotherm of vapor-phase mercury chloride on powdered activated carbon (PAC). The technique is commonly applied to remove mercury-containing air pollutants from gas streams emitted from municipal solid waste incinerators. An alternative form of powdered activated carbon derived from a pyrolyzed tire char was prepared for use herein. The capacity of waste tire-derived PAC to adsorb vapor-phase HgCl2 was successfully measured using a self-designed TGA adsorption system. Experimental results showed that the maximum adsorptive capacities of HgCl2 were 1.75, 0.688, and 0.230 mg of HgCl2 per gram of powdered activated carbon derived from carbon black at 30, 70, and 150 degrees C for 500 microg/m3 of HgCl2, respectively. Four adsorption isotherms obtained using the Langmuir, Freundlich, Redlich-Peterson, and Brunauer-Emmett-Teller (BET) models were used to simulate the adsorption of HgCl2. The comparison of experimental data associated with the four adsorption isotherms indicated that BET fit the experimental results better than did the other isotherms at 30 degrees C, whereas the Freundlich isotherm fit the experimental results better at 70 and 150 degrees C. Furthermore, the calculations of the parameters associated with Langmuir and Freundlich isotherms revealed that the adsorption of HgCl2 by PAC-derived carbon black favored adsorption at various HgCl2, concentrations and temperatures.     

Sorption of native polyaromatic hydrocarbons (PAH) to black carbon and amended activated carbon in soil

Organic pollutants (e.g. polyaromatic hydrocarbons (PAH)) strongly sorb to carbonaceous sorbents such as black carbon and activated carbon (BC and AC, respectively). For a creosote-contaminated soil (Sigma15PAH 5500 mg kg(dry weight(dw))(-1)) and an urban soil with moderate PAH content (Sigma15PAH 38 mg kg(dw)(-1)), total organic carbon-water distribution coefficients (K(TOC)) were up to a factor of 100 above values for amorphous (humic) organic carbon obtained by a frequently used Linear-Free-Energy Relationship. This increase could be explained by inclusion of BC (urban soil) or oil (creosote-contaminated soil) into the sorption model. AC is a manufactured sorbent for organic pollutants with similar strong sorption properties as the combustion by-product BC. AC has the potential to be used for in situ remediation of contaminated soils and sediments. The addition of small amounts of powdered AC (2%) to the moderately contaminated urban soil reduced the freely dissolved aqueous concentration of native PAH in soil/water suspensions up to 99%. For granulated AC amended to the urban soil, the reduction in freely dissolved concentrations was not as strong (median 64%), especially for the heavier PAH. This is probably due to blockage of the pore system of granulated AC resulting in AC deactivation by soil components. For powdered and granulated AC amended to the heavily contaminated creosote soil, median reductions were 63% and 4%, respectively, probably due to saturation of AC sorption sites by the high PAH concentrations and/or blockage of sorption sites and pores by oil.     

A/O-膜生物反应器和A~2O系统中有机物分子量分布的对比研究

采用凝胶过滤色谱(GPC)对A/O-膜生物反应器(A/O-MBR)和A2O系统中有机物分子量分布进行了对比研究.结果表明,A/O-MBR系统中由进水到好氧滤液的有机物分子量分布依次变宽,其趋势恰好与A2O系统相反;A/O-MBR好氧滤液的有机物分子量分布远宽于A2O好氧滤液.A/O-MBR好氧滤液中重均分子量(Mw)＞107 u的有机物占总有机物质量的3.4%,表明正是由于膜的截留作用导致这类大分子有机物在MBR中的累积,而无法像A2O系统一样随出水流走;A/O-MBR系统各段污泥混合液的胞外聚合物(EPS)的分子量分布较分散,说明A/O-MBR系统中微生物新陈代谢产物多,并在膜的截留作用下最终造成了这些产物在膜表面大量的沉积.     

Determination of the Adsorption Isotherm of Vapor-Phase Mercury Chloride on Powdered Activated Carbon Using Thermogravimetric Analysis

Abstract

This study investigated the use of thermogravimetric analysis (TGA) to determine the adsorptive capacity and adsorption isotherm of vapor-phase mercury chloride on powdered activated carbon (PAC). The technique is commonly applied to remove mercury-containing air pollutants from gas streams emitted from municipal solid waste incinerators. An alternative form of powdered activated carbon derived from a pyrolyzed tire char was prepared for use herein. The capacity of waste tire-derived PAC to adsorb vapor-phase HgCl₂ was successfully measured using a self-designed TGA adsorption system. Experimental results showed that the maximum adsorptive capacities of HgCl₂ were 1.75, 0.688, and 0.230 mg of HgCl₂ per gram of powdered activated carbon derived from carbon black at 30, 70, and 150 °C for 500 µg/m³ of HgCl₂, respectively. Four adsorption isotherms obtained using the Langmuir, Freundlich, Redlich-Peterson, and Brunauer–Emmett–Teller (BET) models were used to simulate the adsorption of HgCl₂. The comparison of experimental data associated with the four adsorption isotherms indicated that BET fit the experimental results better than did the other isotherms at 30 °C, whereas the Freundlich isotherm fit the experimental results better at 70 and 150 °C. Furthermore, the calculations of the parameters associated with Langmuir and Freundlich isotherms revealed that the adsorption of HgCl₂ by PAC-derived carbon black favored adsorption at various HgCl₂ concentrations and temperatures.     

沼液中臭味物质的去除方法及其对营养物质的影响

采用臭氧曝气法、粉末活性炭吸附法、颗粒活性炭过滤法、臭氧曝气-粉末活性炭吸附联用法、空气曝气-粉末活性炭吸附联用法对沼液中的氨气、硫化氢、吲哚、挥发酚类等主要致嗅物质的去除情况进行了研究,同时分析了不同方法对沼液中营养物质TN、DN、TP、DP等的影响。结果表明,采用粉末活性炭吸附法处理沼液,臭味物质的去除情况以及营养物质的保留效果最好,当粉末活性炭投加量为15 000 mg/L时,沼液中的硫化氢、吲哚、挥发酚已经完全去除,氨氮、氨气的去除率分别为11.42%、13.98%;DN、DP含量分别减少了10.46%、19.53%,但是TN、TP含量分别增加了6.26%、9.63%。     

水处理工艺去除藻毒素的效果探讨

探讨了饮用水处理的各工艺过程对藻毒素的去除作用,并根据前期已进行的实验对各工艺的优化组合进行了讨论,认为以气浮代替沉淀,并附之以粉末活性炭吸附预处理可有效地去除藻毒素;对没有条件改造沉淀池的水厂可暂时采用预氯化和粉末活性炭吸附组合的工艺也可达到较好的效果;对生物预处理工艺进行适当的强化,可达到对有机物、藻类、藻毒素等物质的有效去除.