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关键词： 膜生物反应器   化学清洗   亲水  

摘要： 近年来,MBR因其独特的优势在污水处理领域得到推广应用,然而膜污染是制约MBR稳定运行的关键因素之一。针对次氯酸钠清洗膜的亲水性丢失问题,采用KMnO_4/KOH体系和甲醇体系分别修复其亲水性,分别对KMnO_4浓度、反应时间、反应温度进行优化,评价修复后膜片膜性能,发现与新膜无明显差异,但接触角变小,表明亲水性得到修复。

关键词： Brewery wastewater   PSB-MBR   Pollutants removal   Resource production potential   Operation parameters   Bioresource biological safety  

摘要： Photosynthetic bacteria (PSB) are considered ideal for high COD wastewater treatment and resource recovery. This work is the first continuous-mode long-term (440 days) pilot study (240 L) by using PSB-membrane (PSB-MBR) system for such purpose. Results showed that the system started-up in 27 days for brewery wastewater and then stably operated under various temperature, initial COD and pH conditions, which showed fast start-up and strong robustness. Comparing with small-batch PSB-MBR system, the capacity of pollutants treatment degradation rate in the pilot-continuous PSB-MBR system was promoted. The operation parameters for pilot-continuous PSB-MBR system were determined as follows: light-micro aerobic, 72 h hydraulic retention time, 1200 mg L-1 inoculum size and 1.0 g L-1 d(-1) organic loading rate, 2.5 F/M. Under these conditions, the COD and NH4+ in effluent were below 80 and 15 mg L-1, respectively. The PSB cell production reached 483.5 mg L-1 d(-1) with protein, polysaccharides, carotenoid, bacteriochlorophyll, and coenzyme Q10 of 420.9, 177.6, 2.53, 10.75, 38.6mg g(-1), respectively, showing great potential of resource recovery fromorganicwastewater. In addition, the collected biomass had no acute toxicity to crucian carps. This work provides a base for the scale-up of this novel technology. (c) 2018 Elsevier B.V. All rights reserved.

关键词： 膜生物反应器   制药废水   微生物降解作用   膜分离技术  

摘要： 制药废水具有水质成分复杂、有机物浓度高、难生物降解、毒性大等特点,是污水处理中的难题之一,传统生物处理技术对其处理效果不稳定。膜生物反应器是微生物降解作用与膜分离技术相结合的一种新型污水处理技术,近些年来在水处理的应用中发展很快。该技术对制药废水的处理有着独特的优势。本文叙述了膜生物反应器的结构和原理,对其在制药废水处理的应用进行重点分析,并对膜生物生物反应器在制药废水处理领域的发展进行了展望。

关键词： 合成气   乙醇   发酵   代谢机理   生物反应器  

摘要： 采用合成气发酵生产燃料乙醇具有反应条件温和、产物耐受性好、原料来源丰富等优点,是燃料乙醇生产的一种新型工艺。文章综述了国内外合成气厌氧发酵的微生物种类,常见合成气乙醇发酵微生物的生长、代谢特点以及底物利用范围;分析了合成气乙醇发酵的Wood-Ljungdahl代谢途径,以及Wood-Ljungdahl代谢途径中涉及的关键酶类甲酸脱氢酶和CO脱氢酶/乙酰辅酶A合成酶;探讨了过程工艺参数如培养介质、还原剂、pH、气体组成、终产物、培养基和培养方法对合成气发酵的影响;比较了不同反应器在体积传质系数等方面的差异,并重点分析了搅拌罐式反应器和柱式反应器等的反应特点。同时,对合成气发酵的未来发展方向进行了展望。

关键词： 猪场废水净化   蛋白核小球藻   生物反应器  

摘要： 为提高小球藻净化猪场废水的效果,在户外条件下系统比较了预处理方式、管道光反应器的种类和光径对蛋白核小球藻生长及其对猪场废水净化效果的影响。结果表明,猪场原废水COD、NH_4^+、PO_4^(3-)、TN、TP含量分别为710、491、54、590和108 mg·L^(-1)时,蛋白核小球藻对经过3级过滤预处理后的猪场废水净化效果最好,其中脱色率及NH_4^+去除率分别高达88.56%和83.48%,显著高于对原废水的处理效果(P<0.05)。在夏季户外条件下,用平铺管道反应器对蛋白核小球藻进行放大培养,发现小球藻能耐受夏季户外高温,生长良好,最终藻粉产量达到0.13 g·L^(-1)。采用直径为5 cm的立式光生物反应器培养蛋白核小球藻,通过循环采收,藻粉产量可达到0.93 g·L^(-1),其蛋白质含量最高达到58.9%,汞、砷、镉、铅含量分别小于0.1、1.0、0.5和4.0 mg·kg^(-1),符合《饲料用小球藻粉》(DB32/T 564-2010)标准。采收小球藻后的出水中,NH_4^+、PO_4^(3-)、色度的去除率均高达90%以上,基本达到国家排放要求。该研究结果可为制定猪场废水的净化及蛋白核小球藻的工业化生产方案提供参考。

关键词： Biofilm membrane bioreactor (BF-MBR)   Petroleum refinery wastewater (PRW)   Wastewater treatment   Nano-attapulgite clay compounded hydrophilic  

摘要： Petroleumrefinery wastewater (PRW) treatments based on biofilm membrane bioreactor (BF-MBR) technology is an ideal approach and biofilm supporting material is a critical factor. In this study, BF-MBR with nanoattapulgite clay compounded hydrophilic urethane foams (AT/HUFs) as a biofilm support was used to treat PRW with a hydraulic retention time of 5 h. The removal rate of 500 mg/L chemical oxygen demand (COD), 15 mg/L NH4+ and 180 NTU of turbidity were 99.73%, 97.48% and 99.99%, which were 23%, 20%, and 6% higher than in the control bioreactor, respectively. These results were comparatively higher than that observed for the sequencing batch reactor (SBR). The death rate of the Spirodela polyrrhiza (L.) irrigated with BF-MBR-treated water was 4.44%, which was similar to that of the plants irrigated with tap water (3.33%) and SBR-treated water (5.56%), but significantly lower than that irrigated with raw water (84.44%). The counts demonstrated by qPCR for total bacteria, denitrifiers, nitrite oxidizing bacteria, ammonia oxidizing bacteria, and ammoniaoxidizing archaea were also higher in BF-MBR than those obtained by SBR. Moreover, the results of 16 s rRNA sequencing have demonstrated that the wastewater remediation microbes were enriched in AT/HUFs, e.g., Acidovorax can degrade polycyclic aromatic hydrocarbons, and Sulfuritalea is an efficient nitrite degrader. In summary, BF-MBR using AT/ HUF as a biofilm support improves microbiome of the actived sludge and is reliable for oil-refinery wastewater treatment. (C) 2018 Elsevier B.V. All rights reserved.

关键词： 厌氧型细菌   生物反应器   资料无线传输   大肠杆菌   氢气  

摘要： 厌氧型细菌在微生物学里是一门拥有广泛兴趣的研究，然而其无氧培养技术仍然十分地不便利。此论文里我们呈现了一项技术可以进行厌氧培养的生物反应器，浊度测量、流体搅拌、气体传送以及资料无线传输等功能均在封闭的厌氧环境完成。其无氧环境是借由气体产气包而非常见生物实验室里的厌氧操作台来达成。此研究以大肠杆菌进行培养并借由不同碳源和氢气当作能量来源来呈现。

关键词： 人表皮生长因子   发酵工艺   植物毛状根   生物反应器  

摘要： 人表皮生长因子（human Epidermal Growth Factor，hEGF）是一种重要的小分子多肽物质，能够影响多种细胞的生长和分化，尤其是皮肤细胞的增殖，因此在医药行业和化妆品行业具有重要的应用价值。然而化学合成hEGF的高成本和低纯度等问题，一直严重制约着其大规模推广应用。因此利用植物或酵母等宿主作为hEGF的生物反应器进行异源合成，引起了人们的极大关注。\n 植物毛状根生产技术是一种崭新且快捷的获取外源蛋白的重要方式。本研究基于植物毛状根技术，以宿主安全性为首要考虑条件，以转基因宿主整体开发利用为主要目的，以大量提取纯化hEGF为重要目标，开发hEGF的生物安全生产技术。选取农业生产上已经证明比较安全的植物材料花生（优良牧草）和抗病毒的优良中草药菘蓝（叶片可食）作为植物宿主，建立安全的hEGF毛状根表达系统，并探究在不同的植物生物反应器中hEGF的蛋白表达能力差异和hEGF促进动物细胞增殖的活性差异。鉴于毕赤酵母表达系统的优良特点，如容易大规模发酵，外泌表达蛋白，容易纯化等优势。本研究将多个独立的hEGF表达盒串联并行到外泌表达载体中，且在构建表达载体过程中避免标记基因引入，提高表达hEGF的安全性，探究转化毕赤酵母GS115菌株从而量产hEGF的可行性。\n 通过上述研究以期建立有效、安全、高效的hEGF表达体系，为利用植物毛状根技术开发hEGF提供新的更具有安全性的表达系统和利用毕赤酵母表达hEGF提供新的实验方法。主要研究结果简述如下：\n （1）首次以花生为宿主，建立了hEGF的花生毛状根表达体系；结果显示转hEGF花生毛状根株系不仅能够有效表达hEGF，而且表达的hEGF能够显著促进动物细胞的增殖活性，证明花生毛状根表达的蛋白是具有生物学活性的。氨基酸序列鉴定结果表明，植物生物反应器表达的hEGF氨基酸C端序列与天然的hEGF氨基酸C端序列完全一致，表明花生毛状根表达的蛋白确实是hEGF。\n （2）转hEGF花生毛状根培养条件简单，仅需普通的MS培养基即可，且无需添加任何外源激素。此外在体外培养条件下，毛状根的生物量增加迅速，连续培养10周仍保持旺盛的生长能力，因此具备放大培养的潜力且具备无限繁殖能力，具有较大应用潜力。\n （3）毛状根内源成分测定实验结果显示，转hEGF花生毛状根能够合成大量的白藜芦醇和总黄酮，表明转hEGF花生毛状根不仅能够合成hEGF，而且能够合成原有的药用成分，因此具备一株多用能力，为花生毛状根株系的整体开发利用奠定了实验基础。\n （4）建立了高效的发根农杆菌R1601和R1601-hEGF介导的菘蓝毛状根遗传转化体系，为菘蓝的植物毛状根技术研究提供了实验基础。然而相对而言，转hEGF菘蓝毛状根继代培养8周已完全褐化，不适于持续培养，因此菘蓝毛状根体系略差于花生体系。\n （5）从生物量积累、hEGF表达水平、继代培养优势和其它药用成分合成等方面对花生毛状根系统和菘蓝毛状根系统进行比较，综合结果表明花生毛状根具备较多的优势，因此是更适合hEGF的植物表达宿主，有望作为hEGF表达宿主进行大规模培养，有潜在的应用价值和商业潜力。\n （6）首次构建了分别含有1到6个hEGF的独立多表达盒载体，并分别转入毕赤酵母GS115，构建了工程菌株。结果表明不同的工程菌株均能有效表达hEGF，且表达的hEGF具有生物学活性，质谱测序结果表明，多独立表达盒表达的hEGF的C端序列与天然hEGF C端序列完全一致。此外hEGF多独立表达盒没有引入标记筛选基因，极大的提高了后续的药用安全性。为利用毕赤酵母工程菌株表达hEGF提供了新的实验方法。\n （7）筛选到了含有6个密码子优化的独立表达盒毕赤酵母GS115菌株，且hEGF的表达能力最高可达14.19mg/L，且该菌株同样没有引入标记筛选基因，为毕赤酵母的高密度安全发酵奠定了实验基础和理论支持。

关键词： Membrane bioreactor-MBR   Noroviruses   Reclaimed water   Reverse osmosis   Sand-anthracite filters   Wastewater treatment plants  

摘要： The importance of noroviruses (NoVs) in the epidemiology of waterborne diseases has increased globally in the last decades. The present study aimed to monitor genogroup I and II noroviruses in different treatment stages of four wastewater treatment plants (WWTPs) in the metropolitan Sao Paulo. WWTPs consist of secondary (activated sludge) and tertiary treatments (coagulation, sand-anthracite filters, membrane bioreactor (MBR)/reverse osmosis (RO) and chlorination). Raw sewage (500 mL) and treated effluents (1 L) were concentrated by celite and reclaimed water (40 L) by hollow-fiber ultrafiltration system. Quantitative (qPCR) and nested PCR with nucleotide sequencing were used for quantification and molecular characterization. NoVs were widely distributed in raw wastewater samples (83.3%-100% NoV GI and 91.6%-100% NoV GII) and viral loads varied from 3.8 to 6.66 log(10) gc L-1 for NoV GI and 3.8 to 7.3 log(10) gc L-1 for NoV GII. Mean virus removal efficiencies obtained for activated sludge processes ranged from 0.3 to 0.8 log(10) for NoV GI and 0.4 to 1.4 log(10) for NoV GII. NoVs were not detected in the reuse water produced by MBR/RO system, while sand-anthracite filters resulted in a NoV GI and GII decay of 1.1-1.6 log(10) and 0.7-1.6 log(10), respectively. A variety of genotypes (GI. 2, GI. 3a, GI. 3b, GI. 5, GII. 1, GII. 4 Sydney 2012, GII. 5, GII. 6, GII. 17) was observed, with a predominance of GI. 2 and GII. 17 in the different genogroups. These results corroborate with recent data about the entry and dissemination of the emerging genotype GII. P17-GII. 17 Kawasaki 2014 in the country, and may indicate a change in the epidemiological patterns of norovirus strains circulation in this region. This is the first large-scale study to evaluate burden and genotypes of noroviruses in WWTPs in Brazil, providing a rapid diagnosis of viruses circulating in the population. (C) 2018 Elsevier B.V. All rights reserved.

关键词： climate change   enviro-economic analysis   membrane bioreactor   optimization model   power pinch analysis   renewable energy  

摘要： This study proposed an optimal hybrid renewable energy system (HRES) to sustainably meet the dynamic electricity demand of a membrane bioreactor. The model-based HRES consists of solar photovoltaic panels, wind turbines, and battery banks with grid connectivity. Three scenarios, 101 sub-scenarios, and three management cases were defined to optimally design the system using a novel dual-scale optimization approach. At the system scale, the power-pinch analysis was applied to minimize both the size of components and the outsourced needed electricity (NE) from Vietnam's electrical grid. At a local-scale, economic and environmental models were integrated, and the system was graphically optimized using a novel objective function, combined enviro-economic costs (CEECs). The results showed that the optimal CEECs were $850,710/year, $1,030,628/year, and $1,693,476/year for the management cases under good, moderate, and unhealthy air qualities, respectively. The smallest CEEC was obtained when 47% of the demand load of the membrane bioreactor was met using the HRES and the rest was supplied by the grid, resulting in 6,800,769 kg/year of CO2 emissions.