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关键词： Wastewater treatment   Membrane bioreactor   Biofilm succession   Biofilms  

摘要： Biofilms developed on support materials with large apertures can be used as live and in-situ formed membranes for solids separation in biofilm-based dynamic membrane bioreactors (bDMBRs). Unlike polymer membranes, biofilms are live, and their composition and structure vary, which further impacts the biofilm resistance. This study repeatedly observed that while starting up a bDMBR to treat biodegradable wastewater, the filtration resistance increased rapidly at the beginning and decreased to a low level corresponding with biofilm succession that was impelled by a variation in the food/microorganism (F/M) ratio. During the rapid rising stage, the F/M ratio was high. Moreover, Meganema, Rhodobacter, Bdellovibrio, Rhizobium, Micobacterium, and Bacillus were the dominant bacterial genera in the biofilms. This promoted biofilm attachment and growth by an excessive secretion of extracellular polymeric substances (EPSs). Consequently, the early biofilms were less permeable and exhibited a resistance of 15.6 x 10(11) m(-1) on the ninth day. As the start-up time increased and the F/M ratio decreased, the biofilm microbial community was altered significantly, with Legionella, Reyranella, Meganema, Hyphomicrobium, and a few uncultured_bacterium being dominant. Accordingly, the biofilm became more permeable and exhibited a resistance of 0.09x10(11) m(-1) on the 46th day. Then, a flux of 42 L/m(2)center dot h was achieved at a pressure of 0.1 kPa. This study indicated that the accumulated resistance in a bDMBR could decrease spontaneously without cleaning by the regulation of the biofilm succession on the support material.

关键词： 佐夫色绿藻   虾青素   培养优化   诱导条件   光生物反应器  

摘要： 佐夫色绿藻具有多种营养生长方式且可以在诱导条件下合成虾青素,是一种藻源天然虾青素生产的新型替代微藻。本研究系统探讨了以醋酸钠为碳源时,醋酸钠浓度、补料方式、p H以及乙醇对色绿藻积累虾青素的影响,并在室外300L管道光生物反应器中对上述优化的诱导条件进行放大验证。结果表明:采用2.5 g/L醋酸钠、每6 d补加2.5 g/L醋酸钠、培养基p H控制在6.5~8.3和添加2%乙醇时,虾青素的含量最高为3.71 mg/g,较优化前的虾青素的含量提高了31.71%,产量为5.37 mg/L。在室外300 L管道光生物反应器中,其最高虾青素含量和产量分别为3.44 mg/g和1.10 mg/L。本研究采用不同诱导条件强化佐夫色绿藻胞内虾青素的积累,验证了佐夫色绿藻在户外光生物反应器规模诱导培养以生产虾青素的可行性。

关键词： 膜生物反应器   农村生活污水   好氧   厌氧   处理技术  

摘要： 叙述了膜生物反应器(MBR)在农村污水处理中的应用进展,分析了农村污水的特点,介绍了MBR的应用现状及分类,归纳了好氧和厌氧MBR在不同工艺、膜材料、膜结构、膜孔径下处理农村污水的效果,及MBR不同组合技术处理农村污水。指出了膜生物反应器运行中膜污染问题,认为在实际应用中应当考虑装置的安装维护、膜组件的清洗难易、设备的使用寿命等实际问题,考虑采用MBR组合工艺处理农村生活污水,以缓解膜污染,提高污水处理效率。

关键词： 高致病性猪繁殖与呼吸综合征病毒   抗原效价   使用浓度   微载体   生物反应器   细胞量   病毒含量   细胞活力  

摘要： 微载体悬浮培养高致病性猪繁殖与呼吸综合征病毒是提升该疫苗产品质量的重要工艺技术,细胞微载体悬浮培养不仅可以提高单位体积内的细胞量、提高病毒产品效价,同时还具有劳动成本低、产品批间差异小等优点。在提升并保证病毒含量的基础上降低微载体的使用浓度,是生产部门提质降本的方向。我公司利用5L和50L生物反应器微载体悬浮培养Marc145细胞,对接毒时细胞活力、细胞密度的选择、接毒剂量、病毒收获时机等工艺参数优化基础上,进行了微载体使用浓度的比较,确定了适合的微载体使用浓度,达到抗原效价和微载体的最佳匹配效果,提升抗原效价的基础上达到最优的使用浓度。

关键词： 免疫细胞   细胞因子诱导的杀伤细胞   细胞活率   肿瘤杀伤力   旋转式生物反应器  

摘要： 目的采用旋转式生物反应器(rotating wall-vessel bioreactor,RWV)与传统的T-Flask培养瓶培养人外周血细胞因子诱导的杀伤(cytokine-induced killer,CIK)细胞,比较CIK细胞的增殖能力、细胞因子分泌情况、细胞杀伤力.方法提取健康志愿者的外周血,分离出外周单个核细胞(peripheral blood mononuclear cell,PBMC),体外诱导成CIK细胞,分别接种到T-Flask培养瓶及RWV中培养.采用台酚蓝染色法检测细胞活率并绘制其生长曲线;ELISA法检测各组CIK细胞的IL-2,IFN-γ,TNF-α分泌情况;乳酸脱氢酶测定法检测CIK细胞对靶细胞的杀伤力.结果与传统的T-Flask培养瓶培养CIK细胞比较,RWV培养CIK细胞增殖数量明显多且生长力旺盛;使用RWV培养CIK细胞能使其分泌更多的IL-2,IFN-γ,TNF-α细胞因子;RWV组培养的CIK细胞对肿瘤细胞的杀伤力更强.结论RWV培养CIK细胞更能提高其增殖能力、细胞因子分泌能力及肿瘤杀伤活力,同时可解决传统细胞培养数量少、稳定性差、易污染、工作量大及周期长等问题,有效地降低临床治疗成本.

关键词： Sweet sorghum particles   Radial mixing   Discrete element method   Rotary drum bioreactor   Parameter determination  

摘要： The mixing of raw materials in a rotary drum bioreactor is important for advanced solid-state fermentation ***,the shape,size,and other properties of pulverized sweet sorghum stalk particles are more complicated than those of the spherical *** this study,a soft rod-shaped discrete particle model was established and verified to simulate the mixing behavior of sweet sorghum stalk particles in a rotary drum *** were inspired by the particle shape and established a rod-shaped particle model by investigating the influence of the shape(length-diameter ratio)and size(diameter)on the particle packing(stack height and bed porosity).We used orthogonal simulations and extremum difference analysis to determine the main factors,optimum level,and groups of other *** on calibrated parameters,twelve sets of simulations of radial mixing in the drum were performed,and the results were compared with experiments conducted under identical operating *** average relative error between the simulation and the experiment was 10.95%,which indicates that they agreed well and that the simulation could predict the mixing process well.

关键词： 光生物反应器   微藻固碳   溶氧消耗   碱性燃料电池  

摘要： 针对微藻固碳过程中藻液产生的高浓度溶氧会抑制藻细胞生长、降低CO2固定效率的问题,搭建了管式光生物反应器实验台用于藻类的高效培养和固碳,提出了利用电化学方法抑制藻液中溶氧效应的研究思路。首先开展管式光生物反应器培养小球藻的实验研究,对比了光生物反应器与锥形瓶2种培养装置对小球藻生长特性的影响,其次实验研究了利用碱性阴离子交换膜燃料电池的阴极氧还原反应去除藻液中的溶解氧。结果表明:管式光生物反应器运行10个周期之后,微藻的质量浓度达到769 mg/L,生物量增长了10倍,培养效果明显优于锥形瓶培养;经过系统持续运行4 h之后,藻液中的溶氧量由18.35 mg/L降低到6.19 mg/L,溶氧消耗效率为66.3%,电池的最大功率密度达到81 W/m^2。研究证明,采用燃料电池的阴极电化学反应可以实现藻液中溶解氧快速有效地消耗,这一方面提升了微藻的固碳效率,另一方面输出了电能,降低了系统能耗。

关键词： 固态反应器   固体废弃物处理   堆肥   好氧发酵   滚筒   气化废水处理  

摘要： 该文分析了堆肥反应器的应用基础,设计了一种容积为100 m3的滚筒式固态生物反应器。该固态生物反应器采用无倾角水平放置,链条传动,厚钢板卷制滚圈等结构,降低了制造难度和成本。该反应器不仅比同类型的反应器成本低,与筒仓式、塔式堆肥反应器相比也有一定的优点。该反应器可日处理固体废弃物10 t^20 t,处理生物质气化废水1 t/d,年生产有机肥5000 t。经过运行一年,达到了设计要求,值得推广应用。

关键词： Spatiotemporally anaerobic/semi-aerobic bioreactor   Biogas evolution   Microbial community   Carbon emission   Energy potential   Rural domestic waste  

摘要： The biogas generation mechanism and its utilization potential in a novel spatiotemporally anaerobic/semi-aerobic bioreactor (STASAB) system with three activated bioreactors (C1, C2 and C3) was analyzed. Methane generation potential was obtained by measurements and estimation methods with similar values of 23.38 and 27.79 kg CH4/t waste, respectively. CH4 and CO2 production was quickly achieved in the STASAB, and the total amount of CH4 and CO2 was low due to the mixed leachate-recirculation operation process among bioreactors, which were at different stages of operation. The microbial communities in different bioreactors were diverse. The leachate-recirculation operation was a critical parameter to effectively enhance the microbial community structure in the STASAB, which can regulate CH4, CO2 and N2O production with global warming potential of 7.479 kg CO(2)e/(t.d). The STASAB had higher energy potential of 1.011 kWh/(t.d) compared with that of conventional landfills and sequentially anaerobic/semi-aerobic bioreactors. Moreover, direct electricity production in the STASAB is recommended for energy utilization with 38.38% GHG emission reduction, and with 131.43 million CNY (Chinese Yuan) benefit per year for national rural waste disposal via utilization of biogas from the STASAB for power generation. Hence, the STASAB shows a notable potential for treating domestic waste in rural areas. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： bone regeneration   buccal fat pad-derived stem cells   perfusion & rotating bioreactor   perfusion bioreactors   beta-TCP  

摘要： Dynamic-based systems are bio-designed in order to mimic the micro-environments of the bone tissue. There is limited direct comparison between perfusion and perfusion-rotation forces in designing a bioreactor. Hence, in current study, we aimed to compare given bioreactors for bone regeneration. Two types of bioreactors including rotating & perfusion and perfusion bioreactors were designed. Mesenchymal stem cells derived from buccal fat pad were loaded on a gelatin/beta-Tricalcium phosphate scaffold. Cell-scaffold constructs were subjected to different treatment condition and place in either of the bioreactors. Effect of different dynamic conditions on cellular behavior including cell proliferation, cell adhesion, and osteogenic differentiation were assessed. Osteogenic assessment of scaffolds after 24 days revealed that rotating & perfusion bioreactor led to significantly higher expression of OCN and RUNX2 genes and also greater amount of ALP and collagen I protein production compared to static groups and perfusion bioreactor. Observation of cellular sheets which filled the scaffold porosities in SEM images, approved the better cell responses to rotating & perfusion forces of the bioreactor. The outcomes demonstrated that rotating & perfusion bioreactor action on bone regeneration is much preferable than perfusion bioreactor. Therefore, it seems that exertion of multi-stimuli is more effective for bone engineering.