群体感应在Pseudomonas aeruginosa生物强化反硝化中的应用研究

采用模拟废水研究了群体感应对反硝化菌株定植（即生物强化作用）及反硝化作用的影响.反硝化功能基因napA表达结果表明,菌株Pseudomonas aeruginosa能够在反应器中成功定植.通过对不同反应器中信号分子的测定发现,群体感应有利于菌株的定植,硝酸盐的去除效率由55%±3.0%提升至81%±3.8%.在菌株定植成功的反应器中加入群体感应淬灭酶后,信号分子失活,促使反应器中硝酸盐的去除率进一步提升至95%以上.     

Improvement of nitrification efficiency by bioaugmentation in sequencing batch reactors at low temperature

Bioaugmentation is an effective method of treating municipal wastewater with high ammonia concentration in sequencing batch reactors （SBRs） at low temperature （10℃）. The cold-adapted ammonia- and nitrite- oxidizing bacteria were enriched and inoculated, respectively, in the bioaugmentation systems. In synthetic wastewater treatment systems, the average NH4＋-N removal efficiency in the bioaugmented system （85%） was much higher than that in the unbioaugmented system. The effluent NH4＋ -N concentration of the bioaugmented system was stably below 8 mg. L1 after 20 d operation. In municipal wastewater systems with bioaugmentation, the effluent NH4＋- -N concentration was below 8 mg·L^-1 after 15 d operation. The average NH4＋ -N removal efficiency in unbioaugmentation system （about 82%） was lower compared with that in the bioaugmentation system. By inoculating the cold-adapted nitrite-oxidizing bacteria （NOB） into the SBRs after 10 d operation, the nitrite concentration decreased rapidly, reducing the NO2 -N accumulation effectively at low temperature. The func- tional microorganisms were identified by PCR-DGGE, including uncultured Dechloromonas sp., uncultured Nitrospira sp., Clostridium sp. and uncultured Thauera sp. The results suggested that the cold-adapted microbial agent of ammonia-oxidizing bacteria （AOB） and NOB could accelerate the start-up and promote achieving the stable operation of the low-temperature SBRs for nitrification.     

固定化外源降解菌强化生物降解作用研究

用一株外源降解菌进行固定化降解蒽的研究。结果表明其降解蒽的最适温度和pH值为30℃和7。经海藻酸钙固定化包埋后,其降解蒽的能力明显提高,在100mg/L的初始浓度下其降解率在12d达到86%。在固定化颗粒中加入少量硅藻土细粉可以提高菌株对蒽的降解能力。     

气浮与生化强化工艺在油田污水工程改造中应用

针对河南油田聚合物驱采油污水,定性分析了污水中的聚合物,研究了聚合物对污水COD的影响.结果表明,污水中聚合物的分子结构发生了一定的变化-CONH2水解为-COOH,同时测定了污水中1 mg/L部分水解聚丙烯酰胺(HPAM)贡献1.3 mg/L COD.随着3次采油技术的发展,油田污水中聚合物含量逐年增大,聚合物含量大幅上升是导致污水COD上升的根本原因.在原有处理工艺基础上,增加絮凝气浮处理工艺单元,改造工程采用“预曝气除油+絮凝气浮+A/O生物膜”处理工艺后,运行结果表明,出水COD为65 ～ 90 mg/L,达到《污水综合排放标准》(GB/T 8978-1996)一级排放标准.     

复合菌剂强化处理高盐废水脱氮效果

将耐盐脱氮复合菌剂投加到序批式生物反应器中,构建生物强化高盐废水处理系统(SBR1),以未投加复合菌剂系统(SBR2)作为对照,分析典型周期中氮素和溶解氧的变化趋势以及盐度冲击对脱氮效果的影响.实验表明,在曝气时间为6h时,生物强化系统脱氮率可稳定在96％以上,出水总氮浓度为3.8 mg/L左右.反应中始终无硝氮、亚硝氮积累,生物强化系统具有同步硝化好氧反硝化能力.当受到5％和7％较高盐度冲击时,生物强化系统表现出优于对照系统的抗盐度冲击能力,能够快速恢复原有活性,且出水总氮低于15 mg/L;当受到0％盐度的淡水冲击时,对照系统中耐盐污泥失活且无法恢复,而生物强化系统只需投加少量(3％)耐盐脱氮复合菌剂,即可快速恢复活性,出水总氮低于15 mg/L.本研究能够为生物强化高盐废水脱氮系统的构建和运行提供技术支持.     

生物强化技术应急处理苯胺泄漏事故

为考察生物强化技术用于苯胺水污染事故应急处理的可行性,以化工园区苯胺泄漏事故为场景,采用高效苯胺降解菌AN-P1强化序批式活性污泥法(SBR),应急处理100～500 mg/L苯胺废水。结果表明,生物强化系统应急处理500 mg/L以下苯胺废水,启动时间约3～4周期(2 d),稳定运行后对苯胺的去除率在96.3%以上,化学需氧量(COD)的去除率在81.3%以上;曝气量(溶解氧)是影响降解的制约因素,其最适曝气量为0.5 m3/h。对处理系统中微生物超氧化物歧化酶(SOD)检测表明,强化系统SOD被诱导产生,对照系统中SOD被抑制,强化系统SOD酶活是对照系统的468倍,表明强化系统可有效消除苯胺降解产生的超氧阴离子自由基的氧化压力。     

生物强化技术在活性污泥处理焦化废水中的实验研究

焦化废水是一种氨氮和有机物浓度较高的难生化降解有机废水。在实验室条件下,将生物强化技术运用于活性污泥处理焦化废水中。结果表明,投加高效菌种,可以改善污泥沉降性能、加快系统启动、增强系统稳定性等。     

Bioaugmentation with a pyridine-degrading bacterium in a membrane bioreactor treating pharmaceutical wastewater

The bacterial strain Paracoccus denitrificans W12, which could utilize pyridine as its sole source of carbon and nitrogen, was added into a membrane bioreactor （MBR） to enhance the treatment of a pharmaceutical wastewater. The treatment efliciencies investigated showed that the removal of chemical oxygen demand, total nitrogen, and total phosphorus were similar between bioaugmented and non-bioaugmented MBRs, however, significant removal of pyridine was obtained in the bioaugmented reactor. When the hydraulic retention time was 60 hr and the influent concentration of pyridine was 250-500 mg/L, the mean effluent concentration of pyridine without adding W12 was 57.2 mg/L, while the pyridine was degraded to an average of 10.2 mg/L with addition of W12. The bacterial community structure of activated sludge during the bioaugmented treatment was analyzed using polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DGGE）. The results showed that the W12 inoculum reversed the decline of microbial community diversity, however, the similarity between bacterial community structure of the original sludge and that of the sludge after bioaugmentation decreased steadily during the wastewater treatment. Sequencing of the DNA recovered from DGGE gel indicated that sp., Sphingobium sp., Comamonas sp., and Hyphomicrobium sp. were the dominant organisms in time sequence in the bacterial community in the bioaugmented MBR. This implied that the bioaugmentation was affected by the adjustment of whole bacterial community structure in the inhospitable environment, rather than being due solely to the degradation performance of the bacterium added.     

生物强化膜生物反应器(MBR)处理邻苯二甲酸二乙酯(DEP)效果及微生物群落结构分析

为强化邻苯二甲酸二乙酯(DEP)降解,将从活性污泥中分离的高效DEP降解菌Arthrobacter sp.LMS13运用到MBR反应器,考察强化系统对DEP去除效果,并通过实时荧光定量(q-PCR)和Illumina Mi Seq技术分别对系统运行期间邻苯二甲酸双加氧酶降解基因(phtA)数量以及微生物群落结构特征进行了分析.结果表明,强化系统能加快反应器启动,对进水浓度为800 mg·L-1的DEP,强化系统和未经强化系统在运行后期(61 d)对DEP平均去除率分别为81%和19%.q-PCR结果显示,在驯化阶段,phtA基因拷贝数上升,但当DEP浓度大于400 mg·L-1时,phtA基因数量下降;phtA基因拷贝数与DEP降解率呈正相关.Mi Seq测序结果进一步表明,高浓度DEP导致系统中群落多样性指数下降,但对强化系统多样性影响相对较小.反应器运行过程中,原活性污泥中占有较高比例的拟杆菌门(Bateroidetes)和厚壁菌门(Firmicutes)丰度降低,ε-变形纲(ε-Proteobacteria)、绿弯菌门(Chloroflexi)在反应系统中逐渐被淘汰,而β-变形纲(β-Proteobacteria)和放线菌门(Actinobacteria)成为系统中的优势菌门,其中红环菌属(Rhodocyclus)、博得氏杆菌属(Bordetella)、节杆菌属(Arthrobacter)为优势菌属,在DEP降解系统中起着主要作用,是保证DEP生物处理效果和维持反应器稳定运行的重要菌属.     

生物修复制剂在溢油污染海岸线中的应用

生物修复制剂是解决溢油污染的"终极策略"。常见的生物修复制剂主要包括生物强化制剂和生物刺激制剂。在实验室条件下,生物强化制剂能有效提高石油污染物的生物降解效率,然而并不能证明生物强化制剂在现场应用时的有效性。然而,大量实验室和现场研究表明,生物刺激制剂能有效地促进石油污染物的生物降解,并且生物刺激效果好于生物添加效果。生物刺激制剂的选择依赖于受污染环境的特性和营养剂本身的特性。如果营养释放速率能够得到有效地控制,缓释肥料是最为理想的营养源。水溶性肥料在低能、细砂质、水动力有限的海岸线更为有效;亲脂性肥料更适于高能、粗砂质的海滩或者有较少露岩的地区。