丝状菌对好氧颗粒污泥形成的影响

通过在SBR中分别接种85%的絮状活性污泥和15%的丝状菌,采用以葡萄糖为碳源配制的人工模拟进水,研究丝状菌对好氧颗粒污泥形成的影响。结果在15 d内培养出理化性能良好的好氧颗粒污泥,表明丝状菌能够加快好氧颗粒污泥的形成。反应器运行期间,COD、NH4+-N、总氮和总磷的平均去除率分别为80.0%、86.9%、70.0%和42.5%,且出水水质稳定,表明好氧颗粒污泥具有良好的除污效果。     

ABR+复合人工湿地处理分散性生活污水的中试研究

研究了ABR+复合人工湿地组合工艺处理分散性生活污水的运行效能及ABR中颗粒污泥的特性。结果表明:在pH和温度的范围分别为6.5～8.5,17.0～28.8℃,ABR和复合人工湿地的HRT分别为3 h(容积负荷平均为1.3 kgCOD/(m3.d)及1.3 d(水力负荷平均为24.6 cm/d)的条件下,系统对COD、NH4+-N、TN、TP和浊度均有较好的去除效果,其平均去除率分别为76%、69%、56%、87%和86%,出水浓度平均分别为37 mg/L、2.73 mg/L、6.93 mg/L、0.18 mg/L和5.05 NTU,ABR中形成了性状良好的颗粒污泥。     

好氧颗粒污泥系统中丝状菌演替规律及其菌丝缠绕特性分析

为达到固液分离的目的,在SBR中将丝状菌颗粒化.研究发现,反应器中相继出现黄色、黑色和白色3种丝状菌颗粒.3种颗粒中,黑色颗粒和白色颗粒孔隙率基本一致,但黑色颗粒粒径远远大于其他2种颗粒,沉速达最大.对3种颗粒和反应器出水进行了丝状菌菌种鉴定,其中黑色颗粒以真菌为主,白色颗粒以微丝菌为主,黄色颗粒为浮球衣菌和Type0041,出水中除以上菌种外还有其他菌种,如Type0581.研究结果表明:丝状菌以弯曲、分支、不规则生长方式易形成丝状化颗粒;单一丝状菌相互缠绕形成的颗粒的强度高于多种丝状菌所形成的丝状菌颗粒.     

挤压法制备Fe-Al-Ce复合氧化物颗粒除氟性能及地下水处理应用

利用粘结挤压法将Fe-Al-Ce复合氧化物粉末材料制备成颗粒材料(GFAC),进行表征、静态和动态吸附除氟性能评价和现场应用.结果显示,优选GFAC颗粒直径为1.6 mm,具有较高的压缩破坏强度33.80 N和除氟性能.GFAC颗粒对氟的吸附过程符合准二级反应动力学方程,吸附速率受膜扩散和内扩散共同控制;在pH 7.0±0.2条件下,GFAC颗粒对氟的饱和吸附容量达到51.28 mg/g(25℃,Langmuir等温吸附模型).不同空间流速(SV)下动态实验出水穿透(1mg/L)时对氟的累积吸附量分别为5.69mg/g (SV=1 h-1)、5.61mg/g (SV=2h-1)、2.83 mg/g (SV=5 h-1),高于常见活性氧化铝除氟剂(AA,1.77 mg/g,SV=1 h-1)及其他报道的颗粒除氟剂.GFAC颗粒在河北现场成功用于实际高氟地下水的处理,在原水氟浓度(3.7±0.3)mg/L和pH 8.0±0.2条件下,对氟的累计吸附量为3.16 mg/g,明显高于AA(0.83mg/g),具有较好的应用前景.     

A/O工艺生物除磷和好氧反硝化效果及影响因素研究

采用A/O工艺处理低碳源城市污水,研究了生物除磷和好氧反硝化脱氮效果及其影响因素。试验结果表明:①磷的出水浓度低于0.8mg/L,去除率达到92%~98%;②影响好氧反硝化的主要因素为DO和HRT。当DO控制在2mg/L左右,HRT控制在6h时,好氧反硝化效果最好。增加了脱氮效率,减少了碳源和需氧量。NH4+-N去除率高达94%,总脱氮率可高达76%左右。     

镍、铬对活性污泥真实产率的影响

采用两个直流完全混合式反应器,研究了Ni(Ⅱ) 、Cr(Ⅵ) 对好氧活性污泥真实产率系数(YH)、COD去除率、MLSS和污泥呼吸作用的影响.结果表明,当Ni(Ⅱ) 、Cr(Ⅵ) 为3 mg/L时,YH(MMLSS/MCOD)从无重金属的0.388分别升高到Ni(Ⅱ) 的0.427和Cr(Ⅵ) 的0.408;COD的去除率不受影响,MLSS增加了7.5%;污泥呼吸作用增强了5%.随着Ni(Ⅱ) 、Cr(Ⅵ) 浓度的进一步增加,YH、COD去除率、MLSS和呼吸作用都迅速下降.当Ni(Ⅱ) 、Cr(Ⅵ) 为15 mg/L时,YH(MMLSS/MCOD)分别为0.289和0.218;而Ni(Ⅱ) 、Cr(Ⅵ) 为25 mg/L时,对污泥呼吸的抑制作用分别达43%和60%.总体来看,Cr(Ⅵ) 比Ni(Ⅱ) 对系统的毒性更大.     

Characteristics of high-sulfate wastewater treatment by two-phase anaerobic digestion process with Jet-loop anaerobic fluidized bed

A new anaerobic reactor, Jet-loop anaerobic fluidized bed （JLAFB）, was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and sulfide inhibition in reactors, were discussed for a JLAFB and a general anaerobic fiuidized bed （AFB） reactor used as sulfate-reducing phase and methane-producing phase, respectively, in two-phase anaerobic digestion process. The formation of granules in the two reactors was also examined. The results indicated that COD and sulfate removal had different demand of influent COD/SO4^2- ratios. When total COD removal was up to 85%, the ratio was only required up to 1.2, whereas, total sulfate removal up to 95% required it exceeding 3.0. The alkalinity in the two reactors increased linearly with the growth of influent alkalinity. Moreover, the change of influent alkalinity had no significant effect on pH and volatile fatty acids （VFA） in the two reactors. Influent alkalinity kept at 400-500 mg/L could meet the requirement of the treating process. The JLAFB reactor had great advantage in avoiding sulfide and free-H2S accumulation and toxicity inhibition on microorganisms. When sulfate loading rate was up to 8. 1 kg/（m^3.d）, the sulfide and free-H2S concentrations in JLAFB reactor were 58.6 and 49.7 mg/L, respectively. Furthermore, the granules, with offwhite color, ellipse shape and diameters of 1.0-3.0 mm, could be developed in JLAFB reactor. In granules, different groups of bacteria were distributed in different layers, and some inorganic metal compounds such as Fe, Ca, Mg etc. were found.     

硝基苯好氧降解菌筛选及其降解特性

针对化学试剂厂和制药厂废水中的硝基苯,经菌源筛选与长期好氧驯化,分离到1株能有效降解硝基苯的菌株Bacillus subilis(枯草芽孢杆菌)。系统研究了其生长条件及降解硝基苯的特性,适宜生长条件: pH为5.0～8.0,温度为30～40℃,NH4Cl浓度为100～200 mg/L,在降解硝基苯的过程中有苯胺生成,这为含低浓度硝基苯废水的生物处理提供了新的途径,即不需要厌氧工艺而直接用好氧技术就可将废水完全无害化。      

Removal of trimethoprim and sulfamethoxazole in artificial composite soil treatment systems and diversity of microbial communities

• Novel ACST allowed biodegradation to effectively remove adsorbed SMX and TMP. • Ammonia and nitrite were efficiently removed in ACSTs and water quality was improved. Four artificial composite soil treatment systems (ACSTs) fed with reclaimed water containing trimethoprim (TMP) and sulfamethoxazole (SMX) were constructed to investigate SMX and TMP biodegradation efficiency, ammonia and nitrite removal conditions and the microbial community within ACST layers. Results showed SMX and TMP removal rates could reach 80% and 95%, respectively, and removal rates of ammonia and nitrite could reach 80% and 90%, respectively, in ACSTs. The MiSeq sequencing results showed that microbial community structures of the ACSTs were similar. The dominant microbial community in the adsorption and biodegradation layers of the ACSTs contained Proteobacteria, Chloroflexi, Acidobacteria, Firmicutes, Actinobacteria and Nitrospirae. Firmicutes and Proteobacteria were considerably dominant in the ACST biodegradation layers. The entire experimental results indicated that Nitrosomonadaceae_uncultured, Nitrospira and Bacillus were associated with nitrification processes, while Bacillus and Lactococcus were associated with SMX and TMP removal processes. The findings suggest that ACSTs are appropriate for engineering applications.     

Influence of hydraulic retention time on behavior of antibiotics and antibiotic resistance genes in aerobic granular reactor treating biogas slurry

Longer HRT can enhance degradation rate of sulfamethoxazole in granular reactor. Longer HRT can reduce accumulated concentrations of TCs and QNs in sludge. Longer HRT may have increased relative abundances of ARGs in aerobic granules. The behavior of antibiotics and the corresponding resistance genes in aerobic granular reactors for treating biogas slurry under different hydraulic retention times (10.7 h, R1; 8 h, R2) was investigated in this study. The results indicated that the hydraulic retention time could affect the effluent concentrations and removal efficiencies of sulfonamides. The average removal rates of tetracyclines, fluoroquinolones, and sulfonamides were 63%, 46%, and 90% in R1, and 62%, 46%, and 86% in R2, respectively. Although the removal efficiencies of tetracyclines and fluoroquinolones were similar in both reactors, the respective accumulated concentrations of tetracyclines and fluoroquinolones in R1 were 7.00 and 11.15 µg/g SS, which were lower than those in R2 (8.92 and 13.37 µg/g SS, respectively). The difference in the relative abundance of target antibiotic resistance genes between both reactors was not significant, yet the average relative abundances of all target resistance genes in R1 were higher than those in R2 after 45 days of operation. The results of this study suggested that a longer hydraulic retention time could enhance the antibiotic removal ability of aerobic granular sludge, yet it may also increase the risk of surplus sludge utilization from a resistance genes point of view.