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关键词： 厌氧氨氧化(ANAMMOX)   基质浓度   短期储存   活性恢复   内源呼吸  

摘要： 在15℃±1℃条件下,将厌氧氨氧化菌混培物分别置于基质浓度为0、60、120 mg·L^(-1)添加比例为1∶1的NH+4-N和NO-2-N环境中短期(15 d)储存,探究不同基质浓度对厌氧氨氧化污泥短期保存及恢复的影响.经过短期储存后进行恢复实验,结果表明,1、2、3号反应器(分别对应0、60、120 mg·L^(-1)基质浓度中储存的厌氧氨氧化菌混培物)中的厌氧氨氧化活性分别下降41. 8%、17. 4%、33. 4.%,1、3号分别由于过度内源呼吸和高基质浓度抑制,导致活性下降较大,2号反应器由于基质浓度相对合适,避免了过度内源呼吸和高基质浓度抑制,使得菌种活性在该基质浓度下保留较好;储存期间,3个反应器内均发生内源呼吸消耗自身有机物的情况,导致EPS含量下降50. 9%、41. 7%、23. 7%和粒径下降31. 6%、16. 7%、8. 2%,表明在基质匮乏期菌体通过内源呼吸的方式维持自身的活性,较高的基质浓度可以在一定程度上延缓内源呼吸过程;在恢复期间,3个反应器分别经过15、10、7 d实现脱氮性能和厌氧氨氧化活性的恢复,表明同菌种增殖富集相比,原系统通过菌种活性增强的方式脱氮性能恢复更快.

关键词： 组织工程皮肤   生物反应器   人工表皮   人工真皮   人工复合皮  

摘要： 组织工程是一门生物科学和工程科学密切交叉的前沿学科,组织工程生物反应器已广泛地应用于人体器官修复领域。组织工程皮肤是通过组织工程相关技术来构建人工皮肤替代物,并具有暂时性乃至永久性替代自身皮肤的功效,目前主要有人工表皮、人工真皮和人工复合皮等。灌注式生物反应器是成功培养组织工程皮肤的关键技术,具有培养基的连续供给、气液界面的维持和相对低的应力环境等优点。

关键词： 生物型人工肝   肝细胞   生物反应器   微载体  

摘要： 目的设计一种新型混合型生物人工肝(HBAL)并通过对模拟肝衰竭血清的净化作用评价其疗效,探讨其临床应用的可行性。方法选用中国人肝细胞株-1(CL-1)作为肝细胞供体,在微重力环境下,肝细胞微载体共培养方法培养至第5天,细胞总量约4.0×109个,细胞密度约为4.0×1010/L,在无菌环境下灌入自制生物反应器中,制成生物部分,非生物部分采用血液灌流+胆红素吸附,生物部分和非生物部分通过两套聚乙烯胶管构成一个封闭的环路,监测模拟肝衰竭血清中未结合胆红素、鹅去氧胆酸,胆酸、血氨经过HBAL循环后浓度的变化以及生物反应器中肝细胞功能、形态及肝细胞活性的变化。结果整个治疗过程中循环前24h内,模拟肝衰竭血清中未结合胆红素(UBD)、鹅去氧胆酸(CDCD),胆酸(CA)和血氨(AA)的浓度分别从(335.3±6.0)、(395.0±5.6)、(155.7±4.5)、(39.0±2.6)μmol/L下降至(106.0±10.9)、(131.8±28.7)、(42.2±7.3)、(3.5±1.0)μmol/L,与0h比较差异有统计学意义(P=0.041),24h后浓度下降趋于平稳;循环48h后,CL-1细胞功能发生变化,生物反应器中模拟肝衰竭血清中的谷丙转氨酶(ALT)、谷草转氨酶(AST)、乳酸脱氢酶(LDH)分别从(25.9±4.2)IU/L、(22.0±3.6)IU/L、(0.28±0.09)μmol/L升高至(31.0±2.6)IU/L、(31.6±8.0)IU/L、(0.41±0.12)μmol/L,与0h比较差异有统计学意义(P=0.027);并且整个反应器中肝细胞的数量和活力在循环48h后也呈现显著性下降(P=0.044)。结论(1)构建了一种新型灌流型生物反应器,该生物反应器中的CL-1细胞能够保持较高的活性和良好的功能。(2)新型混合生物型人肝可以显著降低模拟肝衰竭血清中的未结合胆红素、鹅去氧胆酸,胆酸、血氨的浓度,具有清除这些毒性物质的功能,提示其具有明显的肝功能支持作用。

关键词： 费托合成有机废水   EGSB生物反应器   CODcr去除率  

摘要： 本研究的主要依据是以EGSB生物反应器为核心的厌氧工艺处理某厂高温费托合成除油有机废水的试验结果。研究的主要目的是提供一种费托合成高浓有机废水的处理方法。该方法主要是通过在EGSB反应器中接种、驯化普通厌氧颗粒污泥来实现,还要结合废水水质特点,确定一种合理的进水水质组合,使厌氧微生物能够高效、稳定地处理除油后的费托合成高浓有机废水。试验结果表明:EGSB反应器容积负荷为20kg CODcr/(m^3·d),反应器内温度维持在35～37℃,费托合成除油有机废水不加碱中和及EGSB反应器回流比为500%等条件下,系统依然能够正常运行,使有机废水中有机物的去除率高达96%以上,有效降低了企业经营成本。

关键词： 厌氧氨氧化(ANAMMOX)   活性恢复   颗粒化   基质浓度   胞外聚合物(EPS)  

摘要： 目前运行容易失稳已成为制约厌氧氨氧化(ANAMMOX)工艺应用的因素之一.在保证底物不抑制的条件下,通过对实验室前期运行失稳的连续流全混反应器(CSTR)中的厌氧氨氧化污泥进行活性恢复,研究了滞留的基质浓度对ANAMMOX污泥恢复过程中颗粒化及活性的影响.结果表明,经过126d运行,ANAMMOX污泥活性获得恢复且脱氮能力明显提升.控制高、低基质浓度水平的2个反应器均能实现污泥的颗粒化及氮素的高效去除,NRR最大分别达到16. 97 kg·(m^3·d)^(-1)和14. 43 kg·(m^3·d)^(-1).随着反应器脱氮能力的提高(污泥颗粒粒径增大),R1、R2两个反应器内污泥的胞外聚合物EPS含量(以VSS计)均增大,分别由接种时的34. 45 mg·g^(-1)增大至77. 52 mg·g^(-1)和94. 18 mg·g^(-1),PN/PS由1. 89分别增大到6. 25和6. 84.在一定范围内,PN/PS比值增大有利于ANAMMOX污泥颗粒化,但PN/PS过大会导致颗粒污泥结构失稳上浮,加剧污泥流失现象.

关键词： Anaerobic Membrane Bioreactor (AnMBR)   Control   Fouling   Hydraulics   Modelling  

摘要： The use of anaerobic membrane bioreactor technology (AnMBR) is rapidly expanding. However, depending on the application, AnMBR design and operation is not fully mature, and needs further research to optimize process efficiency and enhance applicability. This paper reviews state-of-the-art of AnMBR focusing on modelling and control aspects. Quantitative environmental and economic evaluation has demonstrated substantial advantages in application of AnMBR to domestic wastewater treatment, but detailed modelling is less mature. While anaerobic process modelling is generally mature, more work is needed on integrated models which include coupling between membrane performance (including fouling) and the biological process. This should include microbial factors, which are important to generation of specific foulants such as soluble and particulate inert organics. Mature and well-established control tools, including better feedback control strategies are also required for both the process, and for fouling control.

关键词： diffused aeration   baseline mass transfer coefficient   water depths   oxygen transfer efficiency   wastewater   energy  

摘要： Over 60 percent of all wastewater treatment plants in the developed countries use the activated sludge process as their secondary treatment system. About 50 to 85 percent of the total energy consumed in a biological wastewater treatment plant is in aeration. The activated sludge process, the most common such process, is performed in large aeration basins to provide air for microorganisms to remove nutrients and pollutants through biodegradation. Designs for the air supply often fail to meet sustained peak organic loading, which may lead to unsatisfactory treatment performance and even plant failure. On the other hand, excessive safety factors used in design for the air supply may similarly lead to unsatisfactory treatment performance and energy wastage. Improper sizing of the aeration system is primarily due to inability to estimate the mass transfer coefficient (K(L)a) correctly for different tank depths, leading to improper blower design and to inappropriate operation, among other things. In general, the efficiency of porous fine-bubble diffuser systems varies from 10 to 30 percent or more, depending on tank depth. The term K(L)a is used in ASCE/EWRI Standard 2-06 to define the apparent volumetric mass transfer coefficient in a non-steady-state clean water test in an aeration tank. This parameter is a function of tank depth, due to the variation of oxygen gas depletion with depth. The objective of this paper is to introduce a baseline oxygen mass transfer coefficient (K(L)a(0)), a hypothetical parameter defined as the oxygen transfer rate coefficient at zero depth, and to develop new models relating K(L)a to the baseline K(L)a(0) as a function of temperature, system characteristics (e.g., the gas flow rate, the diffuser depth Z(d)), and oxygen solubility (C-s). Results of this study on data extracted from the literature indicate that a uniform value of K(L)a(0) that is independent of tank depth can be obtained experimentally. Using the baseline, a family of rating

关键词： induced pluripotent stem cells   vertical-wheel bioreactors   microcarriers   xeno-free  

摘要： BACKGROUND Human induced pluripotent stem cells (hiPSC) are expected to become powerful tools for disease modelling, for the discovery and testing of new drugs and, ultimately, for regenerative therapies. The success of these applications depends on the development of scalable bioprocesses capable of generating large numbers of hiPSC and derivatives. RESULTS CONCLUSION In this work, the novel vertical-wheel single-use bioreactors were used for the first time for the expansion of hiPSC under xeno-free conditions. Cultures were performed on microcarriers in two different scales of vessels (100 and 500 mL with 80 and 300 mL working volumes, respectively), leading to maximum cell densities up to 1.21 +/- 0.02 x 10(6) cells mL(-1) and volumetric productivities of 2.01 +/- 0.04 x 10(5) cells mL(-1) day(-1). The pluripotency as well as a normal karyotype were maintained after cell expansion. Consistency of the processes was confirmed with a different hiPSC line, which is an important aspect for a personalized medicine approach. The results here described demonstrate the feasibility of scalable production of hiPSC in a microcarrier-based system using vertical-wheel bioreactors. The protocols developed in this study provide a Good Manufacturing Practices (GMP)-compliant system for hiPSC manufacturing which may be an important step towards the successful implementation of hiPSC-based products. (c) 2018 Society of Chemical Industry

关键词： Computational fluid dynamics   Large scale industrial fermentation   Uncertain growth kinetics   Feb-batch  

摘要： The knowledge of the effect of uncertainties on kinetic parameters is fundamental, when a model is used to improve the performance of an industrial bioreactor. In this work a 100 m(3) industrial bioreactor operating as a fed-batch is simulated by computational fluid dynamic (CFD) methods to investigate the effects of varying kinetics describing the growth of Saccharomyces cerevisiae. The results of the simulation show that the kinetic parameters used to describe the anaerobic metabolic state have the largest influence on the glucose distribution causing a maximum deviation of 25% of the glucose profile corresponding to the base case. The uncertainties of the parameters describing aerobic metabolism affect the glucose with 2% to 5%. The sensitivity of the kinetics is also investigated for four different volumes of the bioreactor operating as a fed-batch. The uncertainty of the kinetics has the largest impact at the beginning of the process, where the mixing time is relatively low and a small impact is found at the end where the mixing time is high. Finally, the influence of a varying yield coefficient on the development of the cell concentration is investigated. Only a small deviation in the cell concentration is found. However, by comparing the CFD simulation with a simulation where ideal mixing is assumed, a deviation of the biomass concentration of approximately 10 g/L or 33% was predicted for the final volume. This work illustrates the possibility to evaluate the effect of variations in kinetic parameters using CFD, and gives an insight on the effect of potential strain improvements on the performance of a fed-batch process. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

关键词： Electro MBR   Emerging contaminants   Quorum quenching   Pesticides   Wastewater treatment  

摘要： The present study investigated the influence of electric field on the removal of quorum sensing (QS) and emerging contaminants using an electrochemical membrane bioreactor (eMBR). A significant reduction of N-octanoyl- L-homoserine lactone signal molecules (similar to 76%) was achieved in the eMBR, with respect to the level observed in the conventional MBR as the control. Furthermore, the intermittent electric current supply (0.5 mA/cm(2)) was found to be effective for the removal of atrazine and estrone. The degradation of key pharmaceutical compounds, such as diclofenac, carbamazepine, and amoxicillin, was also possible, confirming the applicability of the eMBR system for removing the priority chemical compounds of public health concern.