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关键词： Volatile organic compound   Compact trickle bed bioreactor   Industrial painting shop   Ventilation system   Pollutant biodegradation  

摘要： The automotive painting industry is a source of environmental pollution caused by Volatile Organic Compounds (VOCs) present in the discharged ventilation air. To contribute to the mitigation of this type of air pollution, Ekoinwentyka Ltd. developed-from pilot scale to full scale-and adapted the technology of Compact Trickle Bed Bioreactor (CTBB) whose operating principle builds upon co-current downflow of the gas phase (polluted air) and liquid phase (solution of mineral salts) through a packed bed where active microorganisms are immobilized in the biofilm on the surfaces of packing elements. Pilot-scale bioreactor 0.32 m in diameter and 1.50 m total height had its packed bed inoculated with a consortium of microorganisms dominated by Pseudomonas fluorescens bacteria. During the experimental programme that lasted several months, the flow rate of air drawn from the ventilation system of the painting shop was changing between 1.0 and 10.0 m3/h and the inlet concentration of VOCs ranged from 10 to 200 ppm. By measuring VOC concentration in the purified air, the factor of VOC biodegradation was found to range between 85 and 99%. Based on pilot-scale experiments, full-scale CTBB has been developed 2.8 m in diameter and 10 m total height and installed as an add-on component of the ventilation system of the painting shop. Test operation at gas flow rates up to 6000 m3/h, confirmed VOC biodegradation factor at the level of 85-99% thus proving a positive result of CTBB technology adaptation to the conditions of the automotive painting industry.

关键词： AnMBR   Biomass characteristics   Phenol   Microbial diversity   Salinity fluctuations  

摘要： High salinity is becoming more common in industrial process water and final effluents, particularly when striving to close water loops. There is limited knowledge on the anaerobic treatment of chemical wastewaters characterized by distinct salinity fluctuations. This study investigates the high and fluctuating salinity effects on the conversion capacity and membrane filtration performance of an anaerobic membrane bioreactor (AnMBR) in treating phenol-containing wastewater. The AnMBR operated for 180 days with sodium concentrations between 8 and 37 gNa(+).L-1. At <= 26 gNa(+).L-1, approximately 99% COD and phenol removal efficiencies were achieved. At 37 gNa(+).L-1, phenol and COD removal efficiencies decreased to 86 and 82%, respectively, while the biomass specific methanogenic activity was 0.12 +/- 0.05 gCOD-CH(4)(center dot)gVSS(-1).d(-1). Due to large salinity fluctuations, phenol and COD removal efficiencies reduced to <= 45% but recovered to >= 88%. Compared to phenol conversion, methanogenesis was more severely affected. Calculations showed a maximum in-situ phenol conversion rate of 25.5 ***(-1).d(-1). Concomitantly, biomass integrity was compromised, and the median particle size severely dropped from 65.6 to 4.3 mu m, resulting in a transmembrane pressure increase above 400 mbar. Cake layer resistance to filtration contributed to 85% of the total resistance. Nonetheless, all biomass was effectively retained in the AnMBR. A change in salinity >= 14 gNa(+).L-1 substantially reduced the microbial richness and diversity. The microbial community was dominated by Bacteria belonging to Clostridiales and Archaea of the orders Methanosarcinales and Methanobacteriales. Our findings demonstrate AnMBRs as suitable techniques for treating chemical process water, with possible subsequent reclamation, characterized by high phenols concentrations and largely fluctuating salinity levels.

关键词： MBR   膜污染   生物法   膜污染控制  

摘要： 综述了污水处理过程中,膜生物反应器(membrane bioreactor,MBR)膜污染的成因。关键污染物质,以及近年来蓬勃发展的三种生物学控污策略:酶促清洗、群体感应猝灭、能量解偶联。SMP和EPS是膜污染形成的重要物质,其中,多糖是最为关键污染物质,腐殖质和蛋白质参与使得污染机制更加复杂。生物学控污技术运行条件温和,不会对膜表面造成损害,利于延长膜使用寿命,对多糖、蛋白质等关键污染因子具备较强的控制能力,能清洗去除不可逆的污染。生物学污染控制技术有极大的潜力从源头上解决膜污染和污染带来的高能耗问题,极富发展前景。

关键词： Fermentation   Model analysis   Industrial biotechnology   Dimensional analysis   Model reduction   Parameter estimation   Corynebacterium glutamicum  

摘要： The multiple-input, multiple-output nature of microbial fermentation processes are most often described by nonlinear state space models. In order to apply these models for control purposes, they require the fitting of a set of model parameters so they can provide an accurate description of the fermentation system. In order to prevent overfitting of the experimental data, the parameter estimation procedures should produce unique estimates with small confidence intervals. This is facilitated by dimensional analysis, a tool that provides proper scaling of the dynamic model, removing its dimensional units. However, it is surprising that fermentation models seldom employ dimensional analysis, although it is recognized as a tool that can reduce the number of parameters and thus facilitate a comparison between different sets of data. In this tutorial review, we develop a systematic approach for dimensionless reformulation applied to fermentation systems. The approach is demonstrated on parameter estimation studies for a non-isothermal CSTR model and two common microbial fermentation state space models. It is shown that the analysis reduces the number of parameters in the models to yield identifiable reparameterizations, increases the accuracy of the parameter estimation, facilitates sensitivity analysis, and it can be stated that model identification and dimensional analysis as two concepts/approaches are complementary to each other. These benefits are relevant for the next stage of process optimization and control implementation. This review demonstrates the benefits of the dimensional analysis procedure, especially as an essential model development step for bioreactor systems, and together with a structural identifiability analysis it corresponds to methodologies for model reparameterization and parameter reduction.

关键词： 草甘膦废水   化工强化   厌氧   好氧   反硝化   化学除磷  

摘要： 对江苏某化工厂经过四效浓缩预处理的草甘膦废水采用厌氧生化处理系统+好氧生化处理系统+化学深度除磷组合工艺1与厌氧生物处理系统+好氧生物处理系统+反硝化生化处理系统+化学深度除磷组合工艺2进行处理。结果表明,生物处理系统进水pH控制为中性,停留时间控制为6 h,生化装置控温30~35℃,厌氧、好氧、反硝化溶解氧的质量浓度分别控制在<0.5、>7、<0.5 mg/L,添加4 g/L聚合氯化铝铁进行深度除磷,1 g/L聚丙烯酰胺混凝沉淀。组合工艺1出水中COD和TP、NH_(3-)N、TN的质量浓度分别达到52.3 mg/L和0.601、0、16.9 mg/L,其中COD和TP、NH_(3-)N满足GB 18918-2002的一级标准;组合工艺2使TN的质量浓度降低至3.63 mg/L满足GB 18918-2002)一级标准,且运行效果稳定。

关键词： Antibiotics   Forward osmosis membrane bioreactor (FOMBR)   Forward osmosis (FO)   Municipal wastewater   Biodegradation   Biosorption  

摘要： A hybrid microfiltration forward osmosis membrane bioreactor (MF-FOMBR) was operated with raw municipal wastewater as feed. The fate and removal behaviors of 20 commonly used antibiotics were investigated. With the influent concentration of 4.1-716.9 ng/L (the most prevalent antibiotics were enrofloxacin, sulfamethazine and cefalexin, followed by amoxicillin, lomefloxacin and ampicillin), the system showed 58.9-100% overall removal of all the antibiotics. Almost all the antibiotics was rejected efficiently (86.1-100%) by the FO membrane, except for sulfonamides and trimethoprim (as low as 71.0%) due to their low molecular weights (M.W., 250.1-278.1 g/mol). However, relatively low biological removal (8.7-45.7%) was observed for most antibiotics, except for macrolides (70.6-90.1%) which was effectively removed via biosorption, and beta-Lactams (up to 64.6%) which is readily biodegradable, resulting in their significant accumulation (up to 3.4 folds, with the maximum concentration of 1831.5, 1056.7 and 626.3 ng/L for sulfamethazine, enrofloxacin, and cefalexin, respectively) in the mixed liquor. Different antibiotics showed distinct affinities for sorption to the activated sludge. The solid/liquid partitioning of the antibiotics is governed by their hydrophobicity. All the antibiotics was detected in the draw solution (DS) (with average concentrations of 3.8-100.4 ng/L, and enrofloxacin, amoxicillin and sulfamethazine being the most predominant ones) except macrolides in certain cases, highlighting the need to improve their overall removal via the development and application of denser membranes or integration of necessary physiochemical treatment. The side-stream MF unit acted as a major exit (>50.1% of total mass) for the poorly biodegradable and poorly adsorbed antibiotics to leave the system, preventing their further contamination of the DS. The enrichment of the antibiotics in the MF effluent would also facilitate their final elimination via subsequent advanced tre

关键词： 生化工程   生物制药   生物反应器   生化分离工程   生化制剂工程  

摘要： 王义翘先生是美国麻省理工学院生物技术过程工程中心(BPEC)的创始人。在他的领导下,BPEC通过协同创新和生物化学工程(生化工程)的前沿探索,取得了显著的成就。(1)引领了生化工程进入生物制药新时代。与最初的生化工程概念相比,BPEC的重点发生了很大的转变,目标分子不再局限于抗生素、化学品和燃料等小分子,而是拓展到抗体、细胞因子、血液蛋白质和疫苗抗原等生物大分子,解决这些生物药品大规模生产所遇到的工程科学问题。(2)开启了动物细胞培养工程。当细胞生物学家忙于通过增加滚瓶的数量来扩大生产时,BPEC通过流体力学和传质分析,最大限度地减少剪切应力和扩散限制,成功地实现了动物细胞的生物反应器培养,设计出大规模培养的最佳培养基组成和添加策略,获得了蛋白质翻译后修饰随时间变化的规律,提高了动物细胞反应器的目标蛋白质产量。(3)创新了高质量生物大分子的分离纯化技术,建立了亲和膜、反胶束、电辅助分离等新方法。利用准弹性光散射技术,研究了蛋白质的再折叠和聚集机制,发明了聚乙二醇稳定再折叠中间体的新技术。(4)建立了生化工程协同创新和人才培养体系,促进了BPEC成员之间密切合作和与生物技术企业的密切合作,吸引和培养了众多在生化工程领域有建树的年轻人才。本文还对王义翘先生和BPEC对我国生化工程发展的启示和借鉴做了简要的评述。

摘要： In this study, a recombinantAspergillus sojaebeta (beta)-mannanase produced from carob extract in the microparticle-enhanced bioreactor was applied to locust bean gum (LBG) and guar gum (GG) as hydrocolloids. The effects of enzyme amount (EA), temperature (T), and gum concentration (GC) on mannooligosaccharides (MOSs) enzymatic fabrication were examined using Box-Behnken response surface methodology. Under optimized conditions (GC = 1%,T = 40 degrees C,EA = 7.5 ml, and incubation time = 10 min for LBG andGC = 0.75%,T = 50 degrees C,EA = 7.5 ml, and incubation time = 35 min for GG), the M2, M3, M4, M5, and M6 fabrications from LBG were 455.2, 801.1, 101.1, 346.9, and 1,592.3 ppm, while the M2, M3, and M6 concentrations from GG were 92.85, 220.99, and 1,882.54 ppm, respectively. The M6 was the most dominant MOS from both gums. Consequently, LBG and GG can be potential sources of MOS production. It has been observed that MOS productions can be enhanced by optimizing beta-mannanase enzyme treatment conditions. Practical applications In recent years, MOS has gained attention due to its prebiotic efficacy that prevents infections by regulating the intestinal microbiota and reducing the risk of various chronic degenerative diseases. beta-mannanases are extracellular enzymes that hydrolyze 1,4-beta-D mannosidic bonds in mannan, galactomannan, glucomannan, and galactoglucomannans. Locust bean gum (LBG) and guar gum (GG) can be used in the production of mannooligosaccharides (MOS) which is well known to have prebiotic effects. Both hydrocolloid substances are rich in point of mannans, galactomannans, glucomannans, and galactoglucomannans. Therefore, these compounds can be hydrolyzed to produce MOS from different hydrocolloids using beta-mannanases. In this study, to produce MOS from gums, beta-mannanase obtained fromAspergillus sojaefermentation was used. The results showed that LBG and GG could be a potential source of MOS production. It has been observed that higher amounts

关键词： Mathematical modeling   Parameter estimation   Chemical process optimization   Submerged fermentation  

摘要： The present study concerns to the evaluation of non-linear empirical logistic models applied to bioprocess modeling. The substrate degradation, as a function of fermentation time, enzymatic activity, as a function of substrate degradation, and cell growth, as a function of dissolved oxygen concentration were modeled using this proposed approach. Different concentrations of sugarcane bagasse (5, 10, 13, 15, and 20 g L-1) were used in a stirred tank bioreactor with Aspergillus niger. The parameter estimation, based on assays with 5, 10, 13 and 20 g L-1 of sugarcane bagasse, was performed by non-linear least square method and one assay with 15 g L-1 of sugarcane bagasse was used for models' validation. The results obtained allow to conclude that sugarcane bagasse was efficient as carbon source for cellulases production, requiring no other carbon sources. The use of agricultural waste reduces the production costs of cellulases, making de process feasible. The non-linear empirical models proposed this work allowed to predict the variables. The use of these models could be encouraged to evaluate submerged fermentation's characteristics in new experimental works due to its mathematical simplicity and utility. Besides that, they can provide relevant information from the point of view of process control and optimization because they allow to infer about the inflection point which characterizes the maximum rate of variation of the function. [GRAPHICS] .

关键词： in vitro cultures   Plantform bioreactor   L-phenylalanine   L-tryptophan   glucosinolates   polyphenol compounds   photosynthetic pigments   saccharides   antioxidant activity   antimicrobial activity  

摘要： The study demonstrated the effects of precursor feeding on the production of glucosinolates (GSLs), flavonoids, polyphenols, saccharides, and photosynthetic pigments in Nasturtium officinale microshoot cultures grown in Plantform bioreactors. It also evaluated the antioxidant and antimicrobial activities of extracts. L-phenylalanine (Phe) and L-tryptophan (Trp) as precursors were tested at 0.05, 0.1, 0.5, 1.0, and 3.0 mM. They were added at the beginning (day 0) or on day 10 of the culture. Microshoots were harvested after 20 days. Microshoots treated with 3.0 mM Phe (day 0) had the highest total GSL content (269.20 mg/100 g DW). The qualitative and quantitative profiles of the GSLs (UHPLC-DAD-MS/MS) were influenced by precursor feeding. Phe at 3.0 mM stimulated the best production of 4-methoxyglucobrassicin (149.99 mg/100 g DW) and gluconasturtiin (36.17 mg/100 g DW). Total flavonoids increased to a maximum of 1364.38 mg/100 g DW with 3.0 mM Phe (day 0), and polyphenols to a maximum of 1062.76 mg/100 g DW with 3.0 mM Trp (day 0). The precursors also increased the amounts of p-coumaric and ferulic acids, and rutoside, and generally increased the production of active photosynthetic pigments. Antioxidant potential increased the most with 0.1 mM Phe (day 0) (CUPRAC, FRAP), and with 0.5 mM Trp (day 10) (DPPH). The extracts of microshoots treated with 3.0 mM Phe (day 0) showed the most promising bacteriostatic activity against microaerobic Gram-positive acne strains (MIC 250-500 mu g/mL, 20-21 mm inhibition zones). No extract was cytotoxic to normal human fibroblasts over the tested concentration range (up to 250 mu g/mL).