膨胀床应用中的高密度薄壳型琼脂糖凝胶介质、流体力学与固相分布

Two dense pellicular agarose-glass matrices of different sizes and densities, I.e., AG-S and AG-L, have been characterized for their bed expansion behavior, flow hydrodynamics and particle classifications in an expanded bed system. A 26 mm ID column with side ports was used for sampling the liquid-solid suspension during expanded bed operations. Measurements of the collected solid phase at different column positions yielded the particle size and density distribution data. It was found that the composite matrices showed particle size as well as density classifications along the column axis, I.e., both the size and density of each matrix decreased with increasing the axial bed height. Their axial classifications were expressed by a correlation related to both the particle size and density as a function of the dimensionless axial bed height. The correlation was found to fairly describe the solid phase classifications in the expanded bed system. Moreover, it can also be applied to other two commercial solid matrices designed for expanded bed applications.     

核壳型钕铁硼琼脂糖载体的制备及其膨胀床特性

利用油水乳化法以琼脂糖为壳层材料包埋钕铁硼合金颗粒，制备得到一种新型高密度核壳型钕铁硼琼脂糖载体，并且与商品化膨胀床介质Streamline SP进行了比较. 结果表明，这种载体在膨胀床内的膨胀行为可以用Richardson-Zaki方程来描述. 流速和填充高度的增加都会引起床内轴向混合程度的降低，钕铁硼琼脂糖载体在膨胀床内的轴向混合程度小于Streamline SP.     

膨胀床中QMA Spherosil LS介质粒径分布

对新型的膨胀床吸附介质QMA Spherosil LS在膨胀床内的流体力学性能和粒径分布行为进行了详细的研究. 在实验过程中,通过侧壁设有多个取样口的自制膨胀床装置在线采集床层内部的固液混合物样品,考察了介质填充高度、流速及料液性质对轴向粒径分布的影响. 研究结果表明,膨胀床内QMA Spherosil LS介质的流体力学行为可用Richardson-Zaki方程很好地描述. 在膨胀床中QMA Spherosil LS介质的平均粒径沿轴向存在着明显的变化,但介质密度无明显的改变;这种粒径的轴向分布情况受床层的填充高度和流动相速度的影响. 在忽略细胞与介质相互作用的条件下,3%酵母细胞悬浮液对阴离子交换吸附剂QMA Spherosil LS的粒径分级的影响十分有限.     

琼脂糖凝胶大分子在陶瓷原位凝固成型中的应用

研究了一种新的陶瓷原位凝固成型方法,其原理是依据琼脂糖凝胶大分子在水溶液中加热时溶解,冷却时凝固这一物理变化。对于固相体积分数大于50％陶瓷悬浮体中引入约1％（质量分数）琼脂糖大分子,即可凝胶注模进行各种形状复杂的陶瓷部件成型,获得表面光洁、内部孔隙尺寸和密度分布均匀的陶瓷坯体,并烧结出均匀致密内部无明显缺陷的涡轮转子等异型部件。     

膨胀床吸附层析及其在生化分离中的应用

膨胀床是稳定无返混的流化床,它可直接从料液中吸附目标产物,不需预先除去料液中的颗粒。膨胀床将料液的澄清、浓缩和初步纯化集成于一个单元操作中,大大降低了分离过程的复杂程度,提高分离效率。吸附剂的物性、膨胀床装置、料液的性质以及操作条件等因素对膨胀床的稳定和分离效率有很大的影响。     

厌氧膨胀颗粒污泥床反应器的应用现状与研究热点

介绍了膨胀颗粒污泥床的结构工艺特性。综述了膨胀颗粒污泥床较其它厌氧反应器有优势的应用领域,如在低温条件下运行、处理低浓度废水特别是生活污水,以及对含高悬浮物和含毒性或抑制性物质废水的处理的研究结果与应用状况,同时介绍了为了达到水质排放要求,膨胀颗粒污泥床与其它新型工艺组合的研究现状与成果。     

三种典型扩张床吸附介质的比较分析与评价

扩张床吸附是一种新型的集固液分离、浓缩、纯化于一体的层析技术,其核心为经过特殊设计的吸附介质。比较了Streamline SP、Streamline SP XL和Fastline SP三种常用扩张床介质的理化性质和床层特性,并以乳铁蛋白为模型蛋白,从静态吸附、吸附动力学和动态吸附三方面比较了不同介质的吸附特性。结果表明,介质颗粒小,吸附平衡快;介质密度大,床层稳定性高,适用流速大,过程处理能力高,研究的结果为扩张床吸附介质的理性设计提供指导。     

厌氧膨胀颗粒污泥床反应器的国内研究与应用现状

厌氧膨胀颗粒污泥床(expanded granular sludge bed,EGSB)反应器作为第三代厌氧反应器的典型代表,相比于上流式厌氧污泥床(UASB)反应器具有更高的容积负荷和抗冲击性能,且其还有占地小以及可产生沼气能源等优点,因而被广泛应用于多种高浓度有机废水处理。本文介绍了EGSB反应器的结构原理与运行流程;统计分析了近些年国内EGSB反应器的相关文献及其由小试到工程化的发展历程;概述了EGSB反应器在甲烷化、厌氧氨氧化(ANAMMOX)、生物制氢、同步脱氮除硫方面的研究进展;综述了产甲烷EGSB反应器与生物膜法、序批式活性污泥法和传统活性污泥法等工艺联用的工程应用现状,指出这些工艺均表现出良好的单体去除效果和较理想的整体去除效果,且EGSB反应器在与新兴技术的耦合上也表现出较好的前景。     

季戊四醇在膨胀型阻燃体系中的研究与应用进展

季戊四醇(PER)具有良好的热稳定性、反应活性和成炭性，用于阻燃剂的研究受到国内外学者的普遍关注，在膨胀型阻燃(IFR)体系中得到广泛应用。由于PER价格偏高，如果对防火性能不作特别的要求，从成本的角度考虑，可用淀粉部分取代PER，也可以取得较好的效果：基于PER的膨胀型阻燃剂的发展方向为：热稳定性高、经过表面处理、集酸源、碳源和发泡源于一身的“三位一体”IFR。     

用落球法研究气固浓相流化床表观粘度

用落球法对不同参数条件下的气固浓相流化床床层表观粘度进行测量和线性拟合,得到了流化床的床层屈服应力和塑性粘度与各因素的关系;研究了粘度对分选时间的影响,建立了振动流化床分选时间与表观粘度和物料密度之间的数学模型. 结果表明,在同一气速下,随石英砂颗粒粒级及床层高度增大,床层表观粘度整体增大. 在一定的流化气速范围内,石英砂介质粒级为0.25~0.125 mm、床高190 mm时,床层粘度稳定在0.39~0.51 Pa×s. 加入振动后,床层粘度明显下降,频率15 Hz、振幅1 mm时流化效果较好,床层粘度稳定在0.69~0.95 Pa×s.     

Numerical Simulation of the Hydrodynamics of Gas/Solid Two‐Phase Flow in a Circulating Fluidized Bed with Different Inlet Configurations

The gas/solid flow characteristics in a circulating fluidized bed with two different inlet configurations were investigated by numerical simulation based on an Eulerian approach. In order to describe the interaction between the gas phase and the solid phase and the influence of the solid phase on the gas turbulence, a source term formulation with a more reasonable physical meaning was introduced. The simulation results were validated by the experimental data; then, the model was employed to examine the effect of the inlet configuration on the gas and solid feeding. The simulation results showed that, using the side feeding system, the distributions of solid flow and concentration were highly variable both over the column cross‐section and along the column height. However, such variations can be improved by using the elbow inlet system where the gas and solid are fed from the bottom.     

油页岩循环流化床燃烧室密相区物料颗粒与燃烧特性

在 65t/h油页岩循环流化床锅炉上进行了燃烧室密相区物料特性与燃烧特性的工业试验。得到了极具片状结构特点的油页岩颗粒特性 ,经燃烧破碎磨损后的密相区床料和循环物料的颗粒特性与燃烧特性及相应的锅炉运行参数。试验结果对油页岩循环流化床锅炉的放大设计与运行调节具有一定的参考价值。同时为进一步建立油页岩循环流化床燃烧室密相区的流动、燃烧、传热、磨损、扬析与夹带模型奠定了基础。     

扩张床吸附剂:制备及功能化

Expanded bed adsorption (EBA), a promising and practical separation technique, has been widely studied in the past two decades. The development of adsorbents for EBA process is a challenging course, with the special design and preparation according to the target molecules and specific expanded bed systems. Many types of supporting matrices for expanded bed adsorbents have been developed, and their preparation methods are being consummated gradually. These matrices are activated and then coupled with ligands to form functionalized adsorbents, including ion-exchange adsorbents, affinity adsorbents, mixed mode adsorbents, hydrophobic charge induction chromatography adsorbents and others. In this review, the preparation of the matrices for EBA process is summa-rized, and the coupling of ligands to the matrices to prepare functionalized adsorbents is discussed as well.     

垂直管栓流密相气力输送的参数模拟

通过建立对气体流动及粉体颗粒与颗粒之间相互作用的计算模型,在不同空隙率、粒子速度及管壁的剪应力的情况下,利用离散理论对栓流密相输送系统进行三维模拟,并将模拟结果与实际实验数据进行了比较。由于该模型建模简单、计算量小,模拟结果与实验数据相符,比较容易被工厂采用,以便指导生产。     

球形纤维素-钛白粉复合基质的扩张床流体混合特性

Expanded bed adsorption (EBA) has been widely used in industrial downstream bioprocessing,Solid matrix is the principal pillar supporting the successful application of EBA.A novel spherical ceelulose-titanium dioxide composite matrix was prepared through the method of water-in-oil suspension thermal regeneration.Its typical physical properties were wet density 1.18g.cm^-3,,diameters in the range of 100-300μm ,porosity 85.5%,and water content 72.3%.Expansion characteristics and liquid mixing performance of the matrix in expanded bed were investigated using water and 10% (by mass )glycerol solution as mobile phases,The results indicate that the custom-assembled matrix has a stable flow hydrodynamics and exhibits the same degree of liquid-phase mixing or column efficiency as the commercially available Streamline adsorbent.     

LDPE装置密相输送工艺技术的研究和应用

简述了国内某厂250 kt/a LDPE装置中配套输送系统采用密相输送的主要技术原理,通过技术方案的研究,确定了进行输送的关键技术参数,为装置达到设计指标、稳定生产,提供了可靠的技术基础.     

固相萃取技术及其应用新进展

固相萃取(SPE)是近年来新开发出并得到广泛应用的一种新技术。本文拟通过固相萃取技术的原理、特点、分离模式和操作方法等以及在各个领域的应用和发展前景的介绍与阐述,以对这项新技术在我国的广泛应用起到推动作用。