工业有机废水为共基质培养降解五氯酚厌氧颗粒污泥

研究了工业有机废水和五氯酚(PCP)共存条件下,改良UASB反应器中厌氧污泥的颗粒化过程.实验发现降解PCP厌氧颗粒污泥形成可分成污泥驯化、颗粒污泥出现与成熟3个阶段,污泥颗粒化过程中污泥量、污泥活性和厌氧消化3大类群细菌数量与生态分布发生特征性变化,所培养颗粒污泥具有脱氯降解PCP的活性,产甲烷优势菌为杆状或长丝状产甲烷丝菌,在生物结构上形成互营微菌落,但污泥颗粒无明显层次性微结构.作为共基质的有机废水其种类影响着颗粒化进程、颗粒污泥脱氯活性与产甲烷优势菌.     

不完全厌氧—好氧同反应器工艺处理印染废水的研究

不完全厌氧—好氧同反应器工艺是通过时段切换在同一反应器内实现印染废水处理的过程。结果表明,反应器体积为30L,水力停留时间为12h,总COD_(Cr)去除率达85％,总BOD_5达94.3％,总色度为87.5％,处理出水COD_(Cr)为140mg/L,BOD_5为8mg/L,色度为50倍,达到了国家二级排放标准。实验表明,经厌氧时间段后,BOD_5/COD_(Cr)由0.15提高至0.37,色度由400倍降至50倍,为好氧时间段的COD_(Cr)去除和总的处理效果提供了保证。     

HCR工艺在化工废水处理中的应用

HCR反应器具有所需空间少、占地省、设计集成合理、COD降解率高、空气氧利用率高且操作便利安全等优点。在具有高含盐量、高COD值,可生化性差的化工废水处理工程实例中,取得了良好的实效,验证了HCR工艺系统的实用价值及稳定可靠的性能,体现了HCR工艺系统在化工废水处理领域的优势。     

两级常温厌氧—好氧—固定化微生物组合工艺处理酿酒废水

酿酒废水是一种典型的高氨氮浓度的有机废水.采用两级常温厌氧-好氧-固定化微生物组合工艺对酿酒废水进行中试研究,重点考察了各级工艺对有机物和氨氮的去除效果,并且对影响系统稳定运行的主要因素进行分析.试验结果表明,稳定运行状态下,一级厌氧膨胀颗粒污泥床(EGSB)反应器对有机物去除率可达到70%～90%,处理效果受环境温度影响较大;二级EGSB反应器可以同时去除有机物和氮氧化物;三级好氧接触氧化反应器对有机物的去除率可达到70%,氨氮去除率维持在50%;包埋硝化菌流化床反应器最终能有效地去除水中的氨氮,出水氨氮质量浓度低于15 mg/L.     

Denitrification of synthetic concentrated nitrate wastes by aerobic granular sludge under anoxic conditions

The aim of the present work was to determine the denitrification potential of aerobic granular sludge for concentrated nitrate wastes. We cultivated mixed microbial granules in a sequencing batch reactor operated at a superficial air velocity of 0.8 cm s⁻¹. The denitrification experiments were performed under anoxic conditions using serum bottles containing synthetic media with 225-2250 mg L⁻¹ NO₃-N. Time required for complete denitrification varied with the initial nitrate concentration and acetate to nitrate-N mass ratio. Complete denitrification of 2250 mg L⁻¹ NO₃-N under anoxic conditions was accomplished in 120 h. Nitrite accumulation was not significant (<5 mg N L⁻¹) at initial NO₃-N concentrations below 677 mg L⁻¹. However, denitrification of higher concentrations of nitrate (?900 mg N L⁻¹) resulted in buildup of nitrite. Nevertheless, nitrite buildups observed in present study were relatively lower compared to that reported in previous studies using flocculent activated sludge. The experimental results suggest that acetate-fed aerobic granular sludge can be quickly adapted to treat high strength nitrate waste and can thus be used as seed biomass for developing high-rate bioreactors for efficient treatment of concentrated nitrate-bearing wastes.     

基于不同接种污泥复合型厌氧氨氧化反应器的快速启动特征

为获得快速启动厌氧氨氧化的最佳污泥源及厌氧氨氧化颗粒污泥的快速形成工艺,采用本实验室自主研发复合型CAMBR反应器(厌氧折流板反应器(ABR)+膜生物反应器(MBR),分别接种厌氧颗粒污泥(R1)和絮状反硝化污泥(R2),考察不同接种污泥的厌氧氨氧化启动特征和颗粒化程度.结果表明,R1与R2反应器分别耗时45 d和60 d均成功快速启动厌氧氨氧化,其启动过程均可分为活性停滞期、活性提高期、活性稳定期3个阶段,但每个阶段氮素的去除规律略有不同,稳定运行期内,R1和R2反应器内NH_4~+-N和NO-2-N的平均去除率均高达95%以上;此外,R1反应器中形成了直径0.8~1.6mm为主的厌氧氨氧化红色颗粒污泥,R2反应器则以不规则块状和絮状为主,颗粒化程度较低,两个反应器内均可观察到红色颗粒污泥上浮现象;稳定运行期内NH_4~+-N、NO-2-N和NO_3~--N之间的定量关系分析表明:R1反应器内可能存在着硝酸盐型厌氧氨氧化,致使NH_4~+-N过量转化,R2反应器内则为典型亚硝酸盐型厌氧氨氧化.     

改性与成型层状氢氧化镁铝对不同水体中PO43- 的脱除性能

利用大型工业设备制备出性能稳定的粉末层状氢氧化镁铝(500 kg.批-1,记为Mg-Al LDH),采用沉积法将Mg-Al LDH进行改性与成型,研究了改性与成型层状氢氧化镁铝(记为MG Mg-Al CLDH)对水溶液、废水、不同地带海水中PO34-的动态吸附脱除及再生性能.结果表明,MG Mg-Al CLDH能够有效脱除不同水体中的PO34-,满足污水综合排放一级标准或海水水质一级标准.MG Mg-Al CLDH对PO34-脱除主要是通过离子交换和"结构记忆"效应共同实现的.MG Mg-Al CLDH对水溶液中PO34-的穿透吸附量是未改性时的6倍以上,再生率为126.24%,PO34-的穿透曲线受固定床高度、流量、溶液初始浓度、溶液初始pH值的影响,液膜扩散是吸附过程的主控步骤.当溶液初始浓度低至4.61 mg.L-1时,MG Mg-Al CLDH能将某污水处理厂二级出水中PO34-有效脱除,满足污水综合排放一级标准.当PO34-浓度低至0.38μmol.L-1,MG Mg-Al CLDH仍能将其从海水中有效脱除,达到海水水质一级标准,为解决Mg-Al LDH在实际应用中存在粉末易堵塞床体、无法实现固液分离和再生的问题及水体中磷的脱除提供了一条新型可行之路.     

一株具有好氧反硝化能力真菌的筛选及脱氮性能研究

利用综合筛选法从河流底泥中筛选出一株具有好氧反硝化能力的真菌,通过18S rDNA测序及形态观察,该菌被鉴定为链格孢属真菌。结果表明:该菌碳源底物利用范围广泛,能够利用多种有机碳源进行生长和反硝化。该菌对氨氮的去除主要通过该菌对氨氮的同化作用,而对亚硝酸盐和硝酸盐的去除是同化和反硝化共同作用的结果。当氨氮、亚硝酸盐和硝酸盐同时存在时,该菌优先利用氨氮,但对亚硝酸盐和硝酸盐并无明显的选择性。初始氮浓度和碳氮比对培养基pH和氮素的去除率均有一定的影响。当初始氮浓度和碳氮比合适时,该菌对3种氮素均有很高的去除效率,是一种具有应用前景的除氮菌属。     

Assessment of aerobic biodegradation of lower-chlorinated benzenes in contaminated groundwater using field-derived microcosms and compound-specific carbon isotope fractionation

Biodegradation of lower chlorinated benzenes (tri-, di- and monochlorobenzene) was assessed at a coastal aquifer contaminated with multiple chlorinated aromatic hydrocarbons. Field-derived microcosms, established with groundwater from the source zone and amended with a mixture of lower chlorinated benzenes, evidenced biodegradation of monochlorobenzene (MCB) and 1,4-dichlorobenzene (1,4-DCB) in aerobic microcosms, whereas the addition of lactate in anaerobic microcosms did not enhance anaerobic reductive dechlorination. Aerobic microcosms established with groundwater from the plume consumed several doses of MCB and concomitantly degraded the three isomers of dichlorobenzene with no observable inhibitory effect. In the light of these results, we assessed the applicability of compound stable isotope analysis to monitor a potential aerobic remediation treatment of MCB and 1,4-DCB in this site. The carbon isotopic fractionation factors (ε) obtained from field-derived microcosms were -0.7‰ ± 0.1 ‰ and -1.0‰ ± 0.2 ‰ for MCB and 1,4-DCB, respectively. For 1,4-DCB, the carbon isotope fractionation during aerobic biodegradation was reported for the first time. The weak carbon isotope fractionation values for the aerobic pathway would only allow tracing of in situ degradation in aquifer parts with high extent of biodegradation. However, based on the carbon isotope effects measured in this and previous studies, relatively high carbon isotope shifts (i.e., ∆δ¹³C > 4.0 ‰) of MCB or 1,4-DCB in contaminated groundwater would suggest that their biodegradation is controlled by anaerobic reductive dechlorination.     

一株好氧反硝化菌的分离及特性研究

利用富集培养的方法从城镇污水处理厂的活性污泥中分离到1株好氧反硝化菌,命名为CW。通过形态、生理生化特征和16SrRNA基因序列分析,初步鉴定为睾丸酮丛毛单胞菌(Comamonas testosteroni)。生长特性的研究表明最佳碳源是乙酸钠,最佳碳氮比10:1,最佳DO4.0～6.0mg/L,在此条件下培养24h后,对初始浓度108mg/L的硝酸盐降到27mg/L,去除率达到75%,亚硝酸盐积累仅为4mg/L。以组合载体为填料,挂膜后对污水进行处理,HRT48h,DO5.0mg/L左右,氨氮去除率达到95%左右,最终的NO3-N和NO2-N分别由起始的40～52mg/L和21～28mg/L降为--12～15mg/L和7～9mg/L。