优势菌共代谢深度处理焦化废水

针对经普通生物处理后的焦化废水残留的COD很难去除的问题,提出了利用优势菌共代谢处理焦化废水的方法,通过试验对其进行了分析探讨,得出通过摇床降解试验可使去除率最高达到70％的结论。     

Enhanced Cometabolic Transformation of 4‐Chlorophenol in the Presence of Phenol by Granular Activated Carbon Adsorption

Substrate inhibitions that manifest within the cometabolism system of 4‐chlorophenol (4‐cp) and phenol were alleviated through the application of granular activated carbon (GAC) in batch biodegradation. It was found that 4‐cp was preferentially adsorbed over phenol by the GAC and that 50% to 70% of the adsorption was achieved within the first two hours of contact. The kinetics of 4‐cp adsorption was also much faster than that of phenol, even when the co‐existing phenol was of a significantly higher initial concentration. As a result, competitive inhibition between the two compounds was minimized. Adsorption also caused a lowering of the phenol concentration in solution with a concomitant reduction in the substrate inhibition effect on cell growth. The addition of GAC benefited the biotransformation process through shortening the total degradation time for 600 mg L^?1 phenol and 100 mg L^?1 4‐cp from 42 h to 12 h; and it also made it possible for cells to survive and transform 600 mg L^?1 phenol and as high as 400 mg L^?1 4‐cp in free suspension cultures. Repeated operations in which GAC was reused showed that GAC could be regenerated by the cells, thus rendering the GAC incorporated process amenable to long term operations.     

Semicontinuous microcosm study of aerobic cometabolism of trichloroethylene using toluene

A semicontinuous slurry-microcosm method was applied to mimic trichloroethylene (TCE) cometabolic biodegradation field results at the Que-Jen in-situ pilot study. The microcosm study confirmed the process of aerobic cometabolism of TCE using toluene as the primary substrate. Based on the nucleotide sequence of 16S rRNA genes, the toluene-oxidizing bacteria in microcosms were identified, i.e. Ralstonia sp. P-10 and Pseudomonasputida. The first-order constant of TCE-degradation rate was 0.5 day(-1) for both Ralstonia sp. P-10 and P.putida. The TCE cometabolic-biodegradation efficiency measured from the slurry microcosms was 46%, which appeared pessimistic compared to over 90% observed from the in-situ pilot study. The difference in the TCE cometabolic-biodegradation efficiency was likely due to the reactor configurations and the effective time duration of toluene presence in laboratory microcosms (1 days) versus in-situ pilot study (3 days). The results of microcosm experiments using different toluene-injection schedules supported the hypothesis. With a given amount of toluene injection, it is recommended to maximize the effective time duration of toluene presence in reactor design for TCE cometabolic degradation.     

基于共代谢原理改善TNT炸药废水的可生化性

为改善TNT炸药废水的可生化性,以某实际TNT炸药废水为例,用水质指标评价法和生化模型试验法评价了其可生化性,研究了向废水中添加葡萄糖或与制糖等工业废水混合改善其可生化性。结果表明,原废水可生化性较差,并且随TNT浓度的增加,可生化性不断降低。向TNT废水中添加葡萄糖或制糖等食品工业废水后,可显著改善TNT的可生化性,使TNT废水的生物处理成为可能。     

Model simulations for in situ aerobic cometabolism of trichloroethylene

BACKGROUND: While overall removal of trichloroethylene (TCE) can be estimated from in situ pilot studies of aerobic cometabolism, no quantitative information on the relative importance of the biodegradation and sorption processes is currently available. This paper presents a quantitative method to evaluate the dynamics and the individual removal efficiencies of cometabolic biodegradation and sorption processes using model simulations for in situ aerobic cometabolism. RESULTS: The first‐order rate constant of TCE cometabolism by aerobic toluene‐utilizing bacteria was around 0.2 to 0.3 L mg^?1 day^?1. The TCE partition coefficient of sorption was determined at 16.4 L kg^?1. The sorption process diminished as the sorption capacity of the aquifer solids became saturated. The sustainable TCE removal efficiency due to cometabolic biodegradation for the in situ pilot was determined at 25.8%, 51.8%, and 75.2% for residence times of 0.14 day, 0.57 day, and 1.16 day, respectively, after establishing an indigenous toluene‐degrading consortium. CONCLUSION: The agreement between model simulations and pilot results demonstrates the validity of a model that incorporates fundamental microbial and transport processes of advection, dispersion, and sorption onto the aquifer solids. The mathematical model aids the understanding of both the dynamics and the individual removal efficiencies of sorption and biodegradation processes of in situ bioremediation. Copyright © 2010 Society of Chemical Industry     

Kinetics of cometabolic degradation of 2-chlorophenol and phenol by Pseudomonas putida

In order to address the complex cometabolic degradation of toxic compounds,batch experiments on the biodegradation of 2-chlorophenol (2-CP) and phenol by Pseudomonas putida were carried out.The experimental results show that 2-CP has an inhibitory effect on cell growth and phenol degradation,which demonstrates that the interaction between substrates affects cell growth and substrate degradation.A kinetic model of cell growth and substrate transformation was also developed.The square of the correlation coefficient from the experiment was 0.97,indicating that this model properly simulates the cometabolic degradation of 2-CP and phenol.     

共代谢工艺处理难降解性有机物的研究进展

微生物共代谢是处理难降解性有机物的有效途径,并具有技术经济优势。该文综述了共代谢作用在国内外处理难降解性污染物工艺技术的机理及研究状况,表明序批式生物膜反应器在处理难降解性污染物方面具有光明的应用前景。     

含腈废水生物处理工艺研究

测定了腈纶、丙烯腈生产过程排出的含腈废水的可生物降解性,考察了共基质对含腈废水生化处理的作用,试验了酸化水解-活性污泥-接触氧化联合工艺处理腈纶、丙烯腈混合含腈废水的效果。     

Physiological comparison of Pseudomonas putida between two growth phases during cometabolism of 4‐chlorophenol in presence of phenol and glutamate: a proteomics approach

BACKGROUND: In cometabolic transformation of 4‐chlorophenol (4‐cp) in the presence of phenol and sodium glutamate (SG), a new biphasic growth pattern has been reported. This study investigates the physiological changes of Pseudomonas putida P8 during the biphasic growth by means of 2‐dimensional gel electrophoresis (2‐DE) and MALDI‐TOF analyses. RESULTS: A total of 49 protein spots were selected and identified in the 2‐DE gels from P. putida P8 grown on a mixed substrate containing 200 mg L^?1 of phenol, 200 mg L^?1 of 4‐cp and 1000 mg L^?1 SG. Among them, 16 protein spots were found differentially expressed in the two exponential growth phases during the biphasic growth, including six catabolic enzymes (DmpC, DmpD, DmpE, DmpF, DmpG and AspA) for substrate utilization. The expression of other proteins involved in detoxification and stress responses, carbohydrate and energy metabolism, and environmental information processing as well as a multifunctional xenobiotic reductase (XenA) was quantitatively analyzed and discussed. CONCLUSION: The expression levels of the identified catabolic enzymes during growth in the two growth phases correlated well with the substrate utilization patterns observed in previous kinetics studies. Furthermore, the results show that cells growing on a mixture of aromatic substrates undergo significant physiological changes. Copyright © 2009 Society of Chemical Industry