亚铁离子生物氧化-还原法连续脱除硫化氢

为了降低工业废气中的硫化氢去除工艺成本和运行费用,对三价铁盐吸收与氧化亚铁硫杆菌对Fe²⁺的生物氧化联合作用脱除H₂S进行了研究。通过生物氧化塔中的固定化氧化亚铁硫杆菌细胞再生的Fe³⁺溶液,在H₂S还原吸收塔中脱除H₂S。通过单因素实验分别优化了生物氧化塔和H₂S吸收塔的运行参数,在生物氧化塔曝气量为150 L/h,停留时间为11 h,吸收液中Fe³⁺浓度为0.121~0.143 mol/L,吸收液流量为0.3 L/h,进气量为100 L/h条件下,进气中H₂S浓度分别为2.28和9.11 mg/L,系统连续运行至200 min时趋于相对稳定,当系统连续运行稳定时,H₂S的脱除率可分别达到95%和91%,脱除效果显著。     

不同挂膜方式生物滴滤塔处理含H2S恶臭气体简

采用菌剂挂膜,活性污泥挂膜和自然挂膜3种不同方式形成生物滴滤塔,考察挂膜方式对生物滴滤塔去除H₂S恶臭气体的影响。结果表明,当进气H₂S浓度为5 mg/m³时,菌剂挂膜、活性污泥挂膜、自然挂膜形成的生物滴滤塔出气H₂S浓度分别为15.7~17.4、11.6~14.8和15.0~15.9 μg/m³;塔内压降分别为3~4 mm水柱、6 mm水柱和4~5 mm水柱;喷淋后滤出液中硫酸根的浓度分别为14、22和17 mg/L,硫的转化率分别为45%、60%和50%。当进气H₂S浓度增大至7 mg/m³时,3个塔经过7 d的调整后,均能达到稳定状态,稳定后3个塔中出气H₂S浓度和压降基本没变,喷淋后滤出液中硫酸根浓度依次增大至25、31和30 mg/L左右。采用活性污泥挂膜形成的生物滴滤塔处理H₂S的能力比菌剂挂膜和自然挂膜的高。     

天然沸石负载La2O3-ZnO-TiO2光催化降解活性艳红K-2BP

利用80目天然斜发沸石作载体制备La₂O₃(0.5%)-ZnO(20%)-TiO₂/沸石复合光催化剂,以20 W紫外灯为光源,在自制的光催化反应器中降解活性艳红K-2BP,考察了光照时间、空气通入量、催化剂用量、溶液初始浓度、H₂O₂与Fe³⁺投加量等对活性艳红K-2BP光催化降解率的影响。结果表明,当溶液初始浓度为60 mg/L,催化剂投加量为12 g/L,通气量为1 200 mL/min,光照2.5 h,活性艳红K-2BP的降解率可达99.2%;H₂O₂和Fe³⁺投加量为4 mL/L和3 g/L时,光照1 h活性艳红K-2BP降解率分别为100%和97.2%。紫外可见吸收光谱显示,LZTZ光催化剂可有效降解印染废水。     

微气泡曝气 O3/ H2O2处理 RO 浓水的效能及影响因素简

采用O₃/H₂O₂高级氧化工艺处理炼油厂反渗透（RO）浓水,用溶气泵加压溶气并产生微气泡强化传质,确定装置运行条件,考察气体中臭氧浓度、H₂O₂/O₃初始摩尔比、pH和温度对O₃/H₂O₂处理RO浓水效果的影响,并对RO浓水处理效能进行研究。结果表明,随着气体中臭氧浓度的增加,COD的去除率基本呈线性增加;加入适当量H₂O₂能提高臭氧氧化RO浓水的效果,H₂O₂/O₃初始摩尔比在0~0.8范围内,COD的去除率先增加后下降,H₂O₂/O₃初始摩尔比为0.5时COD去除率最大;pH从6.84增加到9.01,COD去除率逐渐增大,pH为10.03时COD去除率反而降低;在14~28℃范围内,温度低时,升高温度COD去除率增加较大,温度较高时,升高温度对COD去除率的影响较小。为考察该工艺的稳定性,在H₂O₂/O₃初始摩尔比为0.5、溶液pH为8~9、臭氧浓度为80~100 mg/L、温度为10~28℃条件下,对COD为90~140 mg/L的RO浓水氧化处理4~10 h,出水COD维持在39.9~49.9 mg/L,达到《城镇污水处理厂污染物排放标准（GB 18918-2002）》中的一级A标准;去除1 g COD消耗O₃ 1.4~3.3 g,消耗O₃与H₂O₂的总氧量为2.2~4.4 g。     

O3/H2O2降解阿特拉津影响因素研究

采用O3/H2O2氧化去除水中内分泌干扰物阿特拉津,考察了反应条件及水质对去除的影响,并对反应机制进行了初步探讨。阿特拉津初始浓度2 mg/L,投量为7.5 mg/L的O₃单独氧化去除率为27.2%;相同O₃投量下,控制H₂O₂/O₃摩尔比为0.75,5 min阿特拉津的去除率最高可达96.5%;pH 值为7.5～8.5,温度在25～40℃的范围内,都维持了较高的去除率,表明H₂O₂/O₃体系对阿特拉津的去除效果良好,降解速度快,反应条件温和。0.5 mg/L的腐殖酸,对阿特拉津的去除影响不大,腐殖酸浓度为1、2和5 mg/L时,平均去除率分别为63.4%、50.7%和30.2%;碳酸氢钠的浓度为50和200 mg/L时,去除率分别为88.1%和73.8%,说明水质对阿特拉津的去除影响较大。叔丁醇的浓度为5和20 mg/L时,阿特拉津的去除率分别降低到44.7%和27.5%,去除率随自由基抑制剂叔丁醇增加而降低,说明H₂O₂/O₃降解阿特拉津主要为该体系产生的羟基自由基的贡献。     

vis／H2O2／草酸铁处理活性艳红染料的实验研究

采用vis／H₂O₂／草酸铁法，对活性艳红染料废水进行处理。研究了H₂O₂、K₂C₂O₄和Fe₂(SO₄)₃·7H₂O的投加量、pH值和光照时间等因素对染料废水处理效果的影响和最佳处理条件。结果表明，pH值2.5；30%H₂O₂的投加量0.1 mL；0.1 mol/L Fe₂(SO₄)₃·7H₂O的投加量1.0 mL；0.1 mol/L K₂C₂O₄的投加量1.5 mL；光照时间40 min的最佳条件下，70 mg/L的活性艳红模拟染料废水脱色率可达99.82%。通过对vis／H₂O₂／草酸铁法和Fenton法、H₂O₂法、草酸铁法等方法进行对比实验，vis／H₂O₂／草酸铁法明显优于其他方法，是一项有研究价值和开发应用前景的污染治理新技术。     

有机物浓度对厌氧氨氧化脱氮性能影响试验研究

通过间歇试验和连续试验研究了不同有机物浓度对厌氧氨氧化活性及脱氮性能的影响。间歇试验结果表明：自养条件下厌氧氨氧化菌的最大比反应速率为0.189 kg NH⁺₄-N/（kg VSS·d）;当氨氮和亚硝酸盐氮浓度为80 mg/L时,有机物的添加降低了厌氧氨氧化速率,当有机物浓度超过70 mg/L时,厌氧氨氧化菌的最大比反应速率降低到0.05 kg NH⁺₄-N/（kg VSS·d）以下,是反硝化菌与厌氧氨氧化菌竞争亚硝酸盐产生了可逆抑制的结果。连续试验结果表明,高氮低碳源有机环境下厌氧氨氧化能稳定运行,并且比自养系统中总氮的去除率有所提高,当COD值为50 mg/L时,总氮去除率最大,平均值达96.59%,是反硝化菌和厌氧氨氧化菌共同脱氮的结果;当有机物浓度过高时,ANAMMOX对TN去除贡献率持续降低,反硝化不断得到强化,厌氧氨氧化运行不稳定。     

不同高级氧化法对水中低浓度药物甲硝唑降解过程的比较

采用UV、H₂O₂、UV/H₂O₂、Fenton、UV/Fenton和UV/TiO₂方法,对水中低浓度的药物甲硝唑进行降解。通过HPLC和UV-Vis光谱得到的甲硝唑去除率。详细讨论了Fe²⁺、TiO₂和H₂O₂的初始浓度以及溶液的初始pH值对降解效率的影响。结果表明,UV/Fenton和UV/TiO₂ 2种系统对水中低浓度甲硝唑均有很好的去除效果,但前者的光催化效率更高。在甲硝唑浓度=6 μmol/L,H₂O₂和Fe²⁺的初始浓度分别为0.5 mg/L和2.94 μmol/L,pH=4的条件下,UV/Fenton方法对甲硝唑水溶液光催化的最佳效率为95.8%。     

新型高效气体扩散电极的制备与性能

评述了原位产生H₂O₂的电化学法污水处理技术中使用的主要电极,研究了用石墨制备高效气体扩散电极的方法。对石墨用HNO₃与H₃PO₄的混合液改性,石墨与聚四氟乙烯的质量比为2∶1,电极经350℃煅烧1 h,对溶解O₂还原产生H₂O₂的催化活性最高。仅在pH值很低时,电极的活性较差,在pH=3～9时,电极的活性受pH值变化影响较小。在pH=3时电解150 min,电极的电流效率始终高于72%,H₂O₂浓度达到了274.5 mg/L。     

BAF处理生活污水过程中同步去除H2S的试验研究

采用曝气生物滤池处理生活污水的过程中,以混和臭气的空气为气源,以掺入了陶粒和铁炭颗粒的复合填料为载体,研究了反应器的运行条件和参数,结果表明,以混合臭气的空气作为气源对污水处理过程的需氧量基本无影响。当反应器的进气量为40 L/h,进水容积负荷和进气H2S的浓度分别在0.3～1.6 kg COD/(m³·d)和0.8～2.3 mg/m³之间变化时,可以实现出气和出水中H₂S和COD分别小于0.04 mg/m³和90 mg/L,满足同时达标排放的要求。H₂S的同步去除可能是通过微生物的氧化分解和形成FeS沉淀来实现的。     

微氧环境下无色硫细菌和硫酸盐还原菌脱硫

通过间歇曝气形成微氧环境让SRB和CSB实现共生,使含硫酸盐有机废水中硫酸根最终转化成单质硫达到脱硫目的.研究考察了曝气量对SRB还原和CSB氧化的影响,确定了合适的曝气强度和水力停留时间,使得单质硫占系统内总硫比值最大.实验结果显示,在进水COD/SO42-=2000/1500 mg/L、曝气开关时间为2 s/2 min、生化时间为10 h时,单质硫产率最大,为89.53％,SO42-浓度降至最低值72.7 mg/L,还原率达95.1％,此时脱硫效果较好.     

太湖水体附着细菌和浮游细菌的丰度与分布特征

为了探讨太湖水体附着细菌及浮游细菌丰度的变化规律,明确细菌丰度与环境因子的关系,应用荧光显微技术对太湖4个湖区细菌丰度及分布特征进行了研究,并探讨了其与总氮(TN)、总磷(TP)、叶绿素a(Chla)、总悬浮颗粒物(TSS)等环境因子之间的关系.结果表明,太湖水体中附着细菌占优势,占总细菌的65％(总细菌平均值为6.53×106cells/mL,附着细菌平均值为4.25×106 cells/mL,浮游细菌平均值为2.28 × 106 cells/mL);附着细菌与浮游细菌数丰度具有相似的时空分布规律,附着细菌与浮游细菌丰度都是河口区(10#)最高,其次梅梁湾(3 #)、湖心区(8#)和东太湖(24#)较低;春夏季高,秋冬季低;水温、TP对太湖水体中附着细菌及附浮游细菌的丰度影响比较大,它们与水体中附着细菌丰度及附浮游细菌均呈显著的正相关(p＜0.05).太湖不同湖区附着细菌及浮游细菌的数量空间差异是由太湖不同湖区生态环境的异质性引起的.     

Contributions of fermentative acidogenic bacteria and sulfate-reducing bacteria to lactate degradation and sulfate reduction

The roles of fermentative acidogenic bacteria and sulfate-reducing bacteria (SRB) in lactate degradation and sulfate reduction in a sulfidogenic bioreactor were investigated by traditional chemical monitoring and culture-independent methods. A continuously stirred tank reactor fed with synthetic wastewater containing lactate and SO(2-)(4) at 35 degrees C, 10h of hydraulic retention time was used. The results showed that sulfate removal efficiency reached 99%, and sulfide and acetate were the main end products after 20 d of operation. 16S rRNA gene based clone libraries and single-strand conformation polymorphism profiles demonstrated that the proportion of SRB increased from 16% to 95%, and that Desulfobulbus spp., Desulfovibrio spp., Pseudomonas spp. and Clostridium spp. formed a stable, dominant community structure. The decreasing COD/SO(2-)(4) ratio had little effect on the community pattern except that Pseudomonas spp. and Desulfobulbus spp. increased slightly. The addition of molybdate to the influent significantly changed the microbial community, sulfate removal efficiency and the pattern of end products. Clostridium spp., Bacteroides spp. and Ruminococcus spp. became the dominant community members. The main end products switched from acetate to ethanol and then to propionate with the oxidation-reduction potentials increasing from -420 to -290 mV. A lactate degradation pathway was deduced: lactate served as the electronic donor for Desulfovibrio spp., or was fermented by Clostridium spp. and Bacteroides spp. to produce propionate or ethanol, which were subsequently utilized by Desulfobulbus spp. and Desulfovibrio spp. The acidotrophic SRB oxidized part of the acetate finally.     

絮凝菌的细胞融合研究

从活性污泥中分离到具有絮凝特性的絮凝菌株F2和F6,絮凝率在80%以上.为了提高絮凝菌的絮凝效果,利用F2和F6作为亲本菌株,进行原生质体融合.首先对菌株F2和F6进行药物抗性遗传标记选择,然后分别对融合条件进行优化,并对融合子进行絮凝测定.实验结果确定了F2具有氨苄青霉素抗性,F6具有新霉素抗性,青霉素敏感试验中,最适浓度分别为F2为0.6 U/ml.、F6为0.1 U/mL,得到了相应的原生质体及融合子;经絮凝试验验证,数株融合子表现出产絮特性,但絮凝效果与亲本菌株F2和F6相当.     

Degradation of di-butyl-phthalate by soil bacteria

Twelve Gram-positive phthalate ester degraders were isolated from soil. Using Biolog GP2 plates, eight of them were identified as belonging to the Corynebacterium-Mycobacterium-Nocardia group, while the remaining four were unidentifiable. When cultured in the presence of di-butyl-phthalate (DBP) in basal salts solution, five of these isolates accomplished more than 90% of DBP degradation within 48 h (fast group), three were placed in the medium group, and the remaining four were placed in the slow group which caused less than 30% of DBP degradation within the same period of time. A 420 bp DNA fragment was amplified from six isolates and none of them fell within the slow group. When compared with the large subunit of phthalate dioxygenase gene (phtA) of Arthrobacter keyseri, 83% and 91% similarities were evident in the nucleotide and amino acid sequences, respectively. However, no correlation between cell surface hydrophobicity and phthalate degradation ability was evident. Six surfactants (Brij 30, Brij 35, Tergitoltype NP-10, Triton N-101, Triton X-100 and SDS) were tested for their abilities to increase degradation rate. When added at the critical micellar concentration (CMC), they all displayed strong growth inhibition against the three bacteria tested, with Brij 30 been the least toxic to isolates G2 and G11, and Brij 35 had the least inhibitory effect for G1. When half the CMC of Brij 30 was incorporated into the basal salts, the inhibitory effect on DBP degradation remained. Soil helped to minimize surfactant toxicity of surfactant and increase the degradation potential of some of the test bacteria. When DBP-amended soil had been aged for three months, decreases in bioavailability were observed but the effect varied tremendously between different organisms. For isolates G1, G2, G5, G7 and G17 the aging effects were almost non-exist. The present study indicates that selection of a suitable degrader may minimize the undesired effect of aging on bioremediation process.     

Isolation and characteristics of sulfentrazone-degrading bacteria

This study aimed to isolate and characterize bacteria able to use sulfentrazone in the commercial formulation as their sole carbon source. The isolation of the potential sulfentrazone-degrading bacteria was made from soil samples with a recent history of herbicide application and from isolates identified through rDNA sequencing. Subsequently, we assessed the growth of the isolates and their sulfentrazone degradation ability using high-performance liquid chromatography. Twenty-six potential sulfentrazone-degrading bacterial isolates were obtained in pure culture. Through analysis of the rDNA sequences, the predominance of bacterial species of the genus Pseudomonas was found. The isolates presented a differentiated ability of sulfentrazone degradation. The presence of herbicide in the culture medium reduced the log phase of four isolates. Pseudomonas putida, Pseudomonas lutea, Pseudomonas plecoglossicida and three isolates of Pseudomonas sp. showed higher sulfentrazone degradation capacity, which varied from 4 to 15%. This is the first report of the Pseudomonas genre capable of sulfentrazone degradation. The isolates obtained present potential use in bioremediation programs for soil contaminated with sulfentrazone.     

紫外诱变选育脱硫微生物

为了深度脱除石油及其产品中的有机硫,实验从天津大港油田被原油污染的土壤中驯化、分离出对多种硫化合物具有一定脱除能力的枯草芽孢杆菌。以此枯草芽孢杆菌为出发菌株,紫外线为诱变剂进行诱变育种,经过多级水平筛选,并连续进行3次复证后,获得了脱硫效果显著,有效脱硫时间明显缩短的正突变脱硫菌种。该突变菌株对100μg／mLDBT脱硫反应24h,其平均比脱硫活性由突变前的3．78mmol／（h·g）提高到21．70mmol／（h·g）,诱变效果显著,并可直接应用于低硫油品的深度脱硫,有一定的实际应用价值。     

厌氧氨氧化菌活性恢复及富集培养研究

为了防止微生物流失,向厌氧序批式反应器(ASBR)中投加纤维膜(无纺布)作为厌氧氨氧化菌的载体,而使ASBR改为厌氧序批式生物膜反应器(ASBBR),研究了厌氧氨氧化菌活性恢复及富集培养过程中氮负荷提高对ASBBR的影响。经过23d的培养,厌氧氨氧化菌的活性恢复到原有的水平,然后提高TN容积负荷培养厌氧氨氧化菌。至132d时,反应器TN容积去除负荷达到了2.060kg/(m3·d)。整个过程中NH4+-N和NO2--N去除率一直保持在98%以上。当厌氧氨氧化菌活性恢复后,NH4+-N、NO2--N消耗量与NO3--N生成量之比最终趋于一定值(1.00∶1.30∶0.25)。在培养过程中,污泥颜色逐渐由灰色变为红棕色,最终变为浅红色。结果表明,反应器运行很稳定,NH4+-N、NO2--N出水浓度非常低,在短时间内能提高到较高的容积去除负荷。可见,ASBBR很适合厌氧氨氧化菌的富集培养。     

贫营养异养硝化细菌的分离鉴定及硝化性能研究

从水库底泥中分离出1株贫营养异养硝化细菌,命名为菌株Y11。经菌株生理特性研究和16SrDNA测序,鉴定出菌株Y11属于假单胞菌属细菌(Pseudomonas sp.)。考察了温度、pH及C/N对菌株Y11的硝化性能影响,结果表明,菌株Y11进行硝化作用的最适温度为30℃,最适pH为中性,最适C/N为6.0,在该条件下进行4d的硝化反应,菌株Y11对氨氮去除率可达91.42%。