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关键词： 犬细小病毒   生物反应器   纸片载体   转瓶   培养工艺  

摘要： 采用微型生物反应器确定纸片载体上F81细胞最佳的接种密度和最佳接毒剂量,在NBS反应器中验证温度对犬细小病毒YA-16-C66株增殖的影响。经过三次重复试验,确定利用NBS生物反应器培养犬细小病毒YA-16-C66株最佳工艺为:采用同步接毒法,培养基为含1%新生牛血清的199溶液,细胞接种密度为1.5×10^7/g,接毒剂量为0.05 MOI,在pH 7.2条件下,37.0℃培养48 h后降温到35.0℃继续培养72 h,细胞病变达到80%~90%时收获上清液。三批次反应器与转瓶工艺产品比较结果表明:反应器比转瓶收获液病毒含量高101.1~101.9 TCID50/100μL;相同培养面积,反应器所得病毒总量是转瓶所得病毒总量的2.8~18.5倍;相同抗原含量的灭活苗,反应器与转瓶工艺产品无显著性差异,血凝抑制效价均≥896。

关键词： 电子迁移   氮氧化物   污水   反硝化聚磷菌   聚糖菌   电子受体   氧化亚氮  

摘要： 利用厌氧-缺氧-好氧序批式生物反应器(Anaerobic/Anoxic/Oxic-Sequencing Batch Reactor,An/A/O-SBR),以乙酸钠为电子供体,NO_(3)^(-)/NO_(2)^(-)为电子受体,控制反硝化电子受体电子需求为90 mmol/L,经长时间驯化,考察了不同电子受体驯化SBR反硝化除磷及N_(2)O释放特性,并利用化学计量法确定了聚磷菌(Phosphorus Accumulating Organisms,PAOs)和聚糖菌(Glycogen Accumulating Organisms,GAOs)间竞争关系。结果表明,NO3-还原过程中,SBR系统总氮(Total Nitrogen,TN)和总磷(Total Phosphorus,TP)去除率均达95%以上,平均N_(2)O产率为2.4%,PAOs转化碳源(CODin)和反硝化脱氮比例分别为62.0%和76.2%。NO_(2)^(-)增加,厌氧段糖原(Gly)酵解性能增强,Gly消耗与碳源转化比例(ΔGly/CODin)由0.67增至0.80,PAOs活性受抑制,聚磷(Poly-P)合成减少,GAOs竞争优势增强。NO_(2)^(-)-N为30 mg/L,SBR内TP去除率降至50.5%,PAOs转化碳源和脱氮比例分别降至36%和50.6%。PAOs-GAOs共生体系内,GAOs反硝化脱氮过程,削弱了高NO_(2)^(-)对PAOs反硝化除磷的抑制,缺氧阶段NO_(2)^(-)/HNO_(2)积累耦合GAOs反硝化脱氮比例增加,导致高NO_(2)^(-)下TP去除率下降和N_(2)O产率增加。

关键词： 生物反应器   换热器   传热   气含率  

摘要： 生物反应器是微生物代谢反应的核心设备,生物研究反应器的传热对细胞生长、繁殖和代谢的影响至关重要,但到目前为止关于生物反应器的传热研究鲜有报道。本文针对生物反应器传统的换热方式,引入了一种高效换热的板翅式换热器,并通过对气含率、黏度、转速以及传热系数的测定,比较了板翅式换热器和列管式换热器在不通气、通气、黏度以及搅拌与通气条件下的传热系数。结果发现,板翅式换热器的传热系数可达列管式换热器的5~6倍,2种换热器在通气情况下的传热系数分别是不通气时的2~3倍。研究表明在生物反应器中引入新型高效换热器不仅节能降耗,而且有利于发酵工业的发展。本研究可为板翅式换热器在生物反应器的应用提供参考。

关键词： 再生水厂   膜生物反应器   臭氧氧化   活性炭吸附  

摘要： 以北京某再生水厂为研究对象,将膜生物反应器与臭氧及活性炭组合技术应用在高品质的城镇再生水厂项目中。为保证脱氮效果,生物池内回流比例设计为400%,出水指标可达北京市《城镇污水处理厂水污染物排放标准》(DB 11/890—2012)规定的新(改、扩)建城镇污水处理设施基本控制项目排放限值A标准(地表准Ⅲ类),TN去除率可达93.6%。结果表明,该组合工艺出水指标为优,工艺稳定性、安全性高,水处理成本合计为4.36元/m^3,可有效消减城镇污水厂向环境水体排放的污染物总量,具有显著的经济和社会效益,可实现城镇污水排水及综合利用的清洁化和资源化。

关键词： 无土栽培   氮素形态   根系   设施蔬菜  

摘要： 以番茄为试材,采用无机基质栽培的方法,研究了不同营养液浓度(氮浓度分别为3.2 mmol·L-1(T0.4)、5.6 mmol·L-1(T0.7)、8.0 mmol·L-1(T1)、16.0 mmol·L-1(T2)、24.0 mmol·L-1(T3))和硝铵配比(NO-3-N/NH+4-N=100/0(R100)、75/25(R75)、50/50(R50)、25/75(R25)、0/100(R0))对番茄苗期生长的影响。结果表明:营养液浓度和硝铵比对番茄株高和生物量的影响有显著的交互作用。在硝态氮占主导的情况下(R100和R75处理),T2处理番茄地上部生物量最大,较其它处理显著提高7.8%~62.2%。在T0.7与T1浓度下,R75处理较R100处理地上部生物量显著提高7.6%和13.6%。铵态氮含量占主导的R25和R0处理显著降低番茄株高和地上部生物量,降幅达19.6%~26.9%和17.8%~48.6%。总根长、根表面积和根系生物量随营养液浓度的升高而下降,在低浓度条件下(T0.4)完全硝态氮更有利于番茄根系的生长,R100处理根表面积、总根长和根系生物量较其它硝铵比处理显著提高23.7%~88.7%、22.2%~112.7%和5.0%~180.0%,T0.4处理根冠比较T1处理显著提高1.3~1.7倍。硝铵复配相较于单一氮源使SPAD值提高9.9%~13.2%。综上,苗期以壮根为主要目的的管理策略中,推荐营养液浓度EC值控制在0.6~1.4 mS·cm-1,含盐量控制在0.51‰~1.01‰;此时氮浓度为3.2~5.6 mmol·L-1,硝铵比推荐75/25。

关键词： 厌氧膜生物反应器   畜禽养殖废水   沼气   膜污染  

摘要： 厌氧膜生物反应器(AnMBR)是一种新兴的畜禽养殖废水处理技术。文章总结了畜禽养殖废水的水质特点和处理现状,介绍了AnMBR的技术原理与组成结构,并基于当前AnMBR在畜禽养殖废水处理领域的研究进展,系统分析了AnMBR的污染物的去除、沼气产量等性能,介绍了其推广应用所面临的膜污染、氮磷去除率低、有害物质抑制等限制性因素,分析了AnMBR处理畜禽养殖废水的机遇与挑战,并提出了相应的调控措施,以期推动AnMBR的发展与应用。

关键词： Woodchip bioreactor   Desalination   Brine treatment   Denitrification   Salinity  

摘要： This study investigated the effect of brine concentration on nitrate reduction in woodchip bioreactors treating brine from one and two-stage reverse osmosis (RO). An initial field experiment with aboveground, outdoor woodchip bioreactors tested batch experiments using one and two-stage RO brine, and a follow-up lab experiment in temperature-controlled chambers tested the same treatments and a 50:50 mix of one and two-stage brine using aged woodchips (11 months). The effect of brine concentration was greatest in the field experiment in which fresh woodchips were used, with nitrate removal rates of 20-152 g N m(-3) of saturated woodchip d(-1). Brine concentration effect was weaker in the lab experiment with aged woodchips with lower nitrate removal rates of 2-62 g N m(-3) of saturated woodchip d(-1). Results indicate that effect of brine concentration on nitrate reduction was dependent on carbon availability, and that brine concentration may have a smaller effect on nitrate reduction in aged woodchips not exposed to periodic unsaturated conditions. Increased brine concentration increased dissolved organic carbon in the effluent. Sustained nitrate reduction was seen over a wide range of nitrate concentration (40-230 mg N L-1) and salinity (12-43 parts per thousand).

关键词： Aspergillus niger   Inulinase   Purification   Characterization  

摘要： The objectives of this study were to purify Aspergillus niger inulinase produced from sugar-beet molasses in the shaking incubator (100 mL) and stirred-tank bioreactors (5-L and 30-L) by using some downstream processes and to determine enzyme kinetics and characterization. The results showed that the best centrifuge-time combination was 16,873 xg-5min with the purification coefficient of 1.4. Besides, with the ultrafiltration process, the inulinase activities yielded using the shaking incubator, pH-controlled/uncontrolled small-scale bioreactors, and large-scale bioreactor were increased from 1101.3, 2079.2, 1561.3, and 787.5 U/mL to 12,065.2, 21,789.0, 11,296.9, and 2948.1 U/mL with purification coefficients of 5.33, 1.38, 1.46, and 1.67, respectively. Additionally, for the inulinase fromshaking incubator and pH-uncontrolled bioreactor, the values of Km for inulin and sucrose were 17.8 and 49.4mg/mL and 28.8 and 25.9 mg/mL, respectively. As the enzyme amount added to the substrate increased, the activity also increased. Mn2+ is the activator of the enzyme, and Cu2+ and Ag+ are inhibitors of the enzyme. The molecular weight of inulinase has been determined to be between 60 and 70 kDa. Consequently, this study ensures valuable and significant information about the purification and characterization of inulinase for industrial implementations. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Membrane bioreactors   Rinsing process   Mechanism   Energy consumption model  

摘要： In this paper, underlying mechanism of the detachment of foulant particles from the planar surface was analyzed. Meanwhile a new mathematical model was proposed, from an energy viewpoint, to study the variation of energy consumption in the rinsing process. The surface properties of the effluent suspensions at various rinsing time were systematically measured and the interaction energy between different foulant layers were analyzed in detail. The results showed that the model simulation could predict reasonably the energy consumption in the rinsing process under different conditions (R-2 > 0.97). Moreover, the reliability of the model was evaluated by model parameters and model constraints. Additionally, the wide adaptability of the proposed model was verified by considering the planar surface was random rough (R-2 > 0.97) and the situation of real wastewater as feed suspension (R-2 > 0.98). Furthermore, the actual energy consumption for foulant particles breaking away from the planar surface was also analyzed. This paper would provide a novel approach for comprehensive understanding the ex-situ rinsing process in membrane bioreactors.

关键词： Baffles   Bioreactor design   Nitrate   Subsurface drainage   Flashy  

摘要： A relatively wide denitrifying woodchip bioreactor (LWD: 16.8 x 10.7 x 0.91 m) was installed with two flow-routing baffles in Illinois, USA with the design objectives of minimizing inflow manifold-related flow restrictions while maintaining both a relatively consistent footprint and nitrate-removal performance compared to conventional designs. This wide design did not improve the percentage of flow from the field that was treated (generally about 40% of flow treated) compared to other sites. However, the Richards-Baker flashiness index (0.74 to 0.91) and probability of exceedance evaluations indicated site drainage was flashy which might have accounted for the lower than expected performance. Nitrate removal was consistent with other bioreactors despite the new design ideas (22-24% edge of field N loss reduction;0.72 to 1.3 g N removed m(-3) d(-1)). Within the context of the need for accelerated conservation drainage practice adoption across the US Midwest, trying to account for flow uncertainties like flashiness with site-specific designs could be a bottleneck for bioreactor design and implementation. It may be worthwhile to explore possible benefits of a simpler design approach (e.g. standardized plug-and-play designs) since there are many factors at play in bioreactor performance.