固定化微生物脱除工业酸性废气中H_2S的研究

以H 2软性填料作为氧化亚铁硫杆菌的固定化载体 ,构成了固定床生物反应器。在一定操作条件下 ,考察了固定床生物反应器对Fe2 +的氧化速率 ,最大可达 7.6 7g/ (L·h)。并对固定床生物反应器运行中在载体表面形成的络合物进行了研究 ,X射线衍射证明此络合物为黄钾铁矾 [KFe3(SO4 ) 2 (OH) 6]。     

Performance evaluation of a water/silicone oil two‐phase partitioning bioreactor using Rhodococcus erythropolis T902.1 to remove volatile organic compounds from gaseous effluents

BACKGROUND: In the framework of biological processes used for waste gas treatment, the impact of the inoculum size on the start‐up performance needs to be better evaluated. Moreover, only a few studies have investigated the behaviour of elimination capacity and biomass viability in a two‐phase partitioning bioreactor (TPPB) used for waste gas treatment. Lastly, the impact of ethanol as a co‐substrate remains misunderstood. RESULTS: Firstly, no benefit of inoculation with a high cellular density (>1.5 g L^?1) was observed in terms of start‐up performance. Secondly, the TPPB was monitored for 38 days to characterise its behaviour under several operational conditions. The removal efficiency remained above 63% for an inlet concentration of 7 g isopropylbenzene (IPB) m^?3 and at some time points reached 92% during an intermittent loading phase (10 h day^?1), corresponding to a mean elimination capacity of 4 × 10^?3 g L^?1 min^?1 (240 g m^?3 h^?1) for a mean IPB inlet load of 6.19 × 10^?3 g L^?1 min^?1 (390 g m^?3 h^?1). Under continuous IPB loading, the performance of the TPPB declined, but the period of biomass acclimatisation to this operational condition was shorter than 5 days. The biomass grew to approximately 10 g L^?1 but the cellular viability changed greatly during the experiment, suggesting an endorespiration phenomenon in the bioreactor. It was also shown that simultaneous degradation of IPB and ethanol occurred, suggesting that ethanol improves the biodegradation process without causing oxygen depletion. CONCLUSION: A water/silicone oil TPPB with ethanol as co‐substrate allowed the removal of a high inlet load of IPB during an experiment lasting 38 days. Copyright © 2008 Society of Chemical Industry     

2,4,6‐Trichlorophenol and phenol removal in methanogenic and partially‐aerated methanogenic conditions in a fluidized bed bioreactor

A fluidized bed bioreactor (FBBR) was operated for more than 575 days to remove 2,4,6‐trichlorophenol (TCP) and phenol (Phe) from a synthetic toxic wastewater containing 80 mg L^?1 of TCP and 20 mg L^?1 of Phe under two regimes: Methanogenic (M) and Partially‐Aerated Methanogenic (PAM). The mesophilic, laboratory‐scale FBBR consisted of a glass column (3 L capacity) loaded with 1 L of 1 mm diameter granular activated carbon colonized by an anaerobic consortium. Sucrose (1 g COD L^?1) was used as co‐substrate in the two conditions. The hydraulic residence time was kept constant at 1 day. Both conditions showed similar TCP and Phe removal (99.9 + %); nevertheless, in the Methanogenic regime, the accumulation of 4‐chlorophenol (4CP) up to 16 mg L^?1 and phenol up to 4 mg L^?1 was observed, whereas in PAM conditions 4CP and other intermediates were not detected. The specific methanogenic activity of biomass decreased from 1.01 ± 0.14 in M conditions to 0.19 ± 0.06 mmolCH₄ h^?1 gTKN^?1 in PAM conditions whereas the specific oxygen uptake rate increased from 0.039 ± 0.008 in M conditions to 0.054 ± 0.012 mmolO₂ h^?1 gTKN^?1, which suggested the co‐existence of both methanogenic archaea and aerobic bacteria in the undefined consortium. The advantage of the PAM condition over the M regime is that it provides for the thorough removal of less‐substituted chlorophenols produced by the reductive dehalogenation of TCP rather than the removal of the parent compound itself. Copyright © 2005 Society of Chemical Industry     

Kinetic analysis for effect of initial substrate concentration on growth and secondary metabolite production in cultures of Nicotiana tabacum

Suspension cultures of tobacco cells were studied using airlift and rotary-drum bioreactors. The effect of initial concentrations of a major substrate, sucrose, on the growth and production of a secondary metabolite, phenolic compounds, was investigated. The dry weights and total concentrations of the phenolic compounds increased with the initial sucrose concentration in both bioreactors. Both bioreactors were found to have the same tendency for the effect of initial sucrose concentration. The structured model, presented previously was modified by considering that sucrose was hydrolyzed to glucose and fructose by an enzymatic reaction. The previous and the new models were applied to the above two sets of experimental data obtained with two bioreactors, independently. The hydrolysis of sucrose was elucidated to contribute slightly to the overall kinetics of growth and secondary metabolite production in these cultures. Furthermore, the levels of shear damage in each bioreactor were quantitatively compared based on the death rate constant, k_i, which is one of the model constants.     

厌氧膜生物反应器在废水处理中的研究进展

厌氧膜生物反应器是一种处理高浓度有机废水的有效工艺.综述了厌氧膜生物反应器的特征,在工业废水处理中的应用以及低温下厌氧处理低浓度废水的效果,并展望了厌氧膜生物反应器的应用前景.     

膜生物反应器技术处理洗浴废水的工程应用

根据洗浴废水的水质水量，设计了生物接触氧化和膜生物反应器相结合的处理工艺(水量为120m^3／d)。通过对工艺相关设计参数的选取和调试运行结果表明，该工艺具有处理效果稳定、抗冲击负荷强以及操作简便等优点。     

生化反应工程与工艺研究进展

对生化反应工程现状及发展趋势进行了综述 ,并着重对生物反应器工程的地位、研究内容、研究方法进展、新型生物反应器的开发前景等作了介绍。同时还简要地介绍了生物技术及工艺的研究现状     

生物流化床预处理黄浦江原水中试研究

对采用悬浮填料的生物流化床原水预处理技术进行了探讨。分析了自然挂膜条件下的工艺启动过程。在8个工况条件下，流化床对污染物的去除效果。中试运行表明；在温度适谊，停留时间为60min，填料填充率为50%条件下，氨氮平均去除效率达到77.6%。氨氮的比表面去除负荷与温度线性相关。相关系数为0.911;CODMn平均去除率为6.5%。中试装置在温度10.6℃条件下，重启动需要4d，即对污染物有较好的去除效果；由于填料的完全流化，池体内溶解氧传质效率高，出水接近饱和溶解氧；进出水浊度变化不大。填料和池体本身不会积泥，不需反冲洗。     

Enzymatic modification of canola/palm oil mixtures: Effects on the fluidity of the mixture

The bioreactor system to interesterify edible oils and fats at an ultra-micro aqueous phase of 100 ppm and less was investigated. The adsorption of lecithin, together with lipase onto a carrier, was effective for conducting the interesterifying reaction efficiently for oils and fats in micro aqueous phase. To improve the handling properties of palm oil at rather low temperature, palm oil was blended with canola or soybean oil, and then these blended oils were modified by enzymatic selective interesterification in a solvent-free, ultra-micro aqueous bioreactor system with an immobilized lipase that had 1,3-positional specificity. The effects of enzymatic interesterification were confirmed by triglyceride determination, by solid fat content profiles and by cloud point profiles, which were also compared to products of chemical interesterification. The improvement in the fluidity of blended oils with canola oil by the enzymatic reaction was bigger than with soybean oil, and chemical interesterification had no effects on the fluidity of blended oils.     

两液相生物反应器研究进展

介绍了两液相反应器的进展及存在问题，两液相反应器仍处于试验阶段，其主要问题是生物催化剂在界面的聚集损失活性等。