管式电反应器在环保领域的研究进展

管式电反应器是一种新型的电化学反应结构元件,以其体积小、传质性能好、效率高而备受关注.本文对管式电反应器的结构、特点及类型做了简要介绍,并就管式电反应器在环境保护等应用领域的研究现状和进展进行了综述,最后对其未来的发展作了展望.     

一种新型电化学反应器

固定床电化学反应器是近年来开发出的一种新型电化学反应设备,该反应器的工作电极是填充在床层内的导电颗粒及网状结构材料等。它的电极比表面积大,工作电极不再局限于两维电极的外表面,而是在床层中填充材料的外表面上发生反应。固定床电化学反应器是一种三维电极电化学反应器,与传统的两维电极电化学反应器相比具有以下特点: ①结构紧密,传质速率怏,空时速率     

电磁感应管式反应器用于化工反应设备的可行性研究

电磁感应加热具有加热迅速、能效高、温度控制实时准确等特点,利用其加工的管式反应器与传统电加热管式反应器进行对比实验研究和数据模拟,根据电磁感应管式反应器使用寿命长、维护简单、功率可调可控、使用安全的特点,讨论了电磁感应管式反应器用于化工反应设备的可行性。     

固定床电化学反应器研究(Ⅱ)硝基苯电化学还原制备对氨基苯酚

研究了在固定床电化学反应器内硝基苯电化学还原制备对氨基苯酚的过程.采用文献[7,8]建立的固定床电化学反应器模型对该反应过程进行了反应器设计.实验测得该反应的摩尔选择性β≥80%,电流效率η_i≥75%,反应器表观电流密度i≥1500A/m~2.本研究为固定床电化学反应器内硝基苯电化学还原制备对氨基苯酚过程工业化奠定了重要的理论基础.     

工业废水电化学处理技术的进展及其发展方向

综述了工业废水电化学处理技术的进展和应用.介绍了电化学氧化、电化学还原、电絮凝、电气浮、电渗析等方法.阐述了电化学氧化技术目前没有工业化的主要原因是低的电流效率、高能耗和大的操作费用,如何提高传质特性、电流效率、开发用于废水处理的高效电解槽是亟待解决的问题.特别指出了未来工业废水电化学处理技术的发展方向是生物难降解废水处理用的阳极材料、电化学反应器、电化学组合技术、生物膜电化学反应器工艺.     

管式电化学反应器提高传质途径的研究进展

基于CFD软件模拟传质系数和理论公式验证的基础上，分析了改变管式反应器结构、电极布置形式和反应器运行模式等提高传质的方法，对旋转电极的开发和其在污废水中的应用提供了理论支撑和应用方向。     

生物柴油制备过程中反应器的研究进展

叙述了管式和滴流床等传统反应器和膜反应器、微通道反应器、反应蒸馏反应器等新型反应器在生物柴油制备的应用和发展,并对反应器的应用前景做了评述和展望。认为改进的传统反应器和新型反应器在生物柴油生产中都有一定的发展前景。新型反应器仍需要解决一些基本的过程问题,如微通道反应器的平行放大控制、腐蚀,膜反应器的选择性．反应蒸馏反应器的模型放大优化问题。     

加压管式反应器的模糊控制

原硝酸铵生产装置中,加压管式反应器的控制方式不能完全满足生产要求。对其进行了分析研究,论述了模糊控制技术在加压管式反应器上的应用方案,成功地用于生产,取得了良好效果。     

乙烯技术发展与超短接触反应器

基于对管式炉理解解技术的发展和超短接触反应器基础研究的综述，分析了管式炉裂解技术存在的局限和超短接触反应器的技术特点以及超短接触反应器烃类裂解工艺所具有的技术优势。     

固定床电化学反应器研究(Ⅱ)硝基苯电化学还原制备对氨基苯酚

研究了在固定床电化学反应器内硝基苯电化学还原制备对氨基苯酚的过程.采用文献[7,8]建立的固定床电化学反应器模型对该反应过程进行了反应器设计.实验测得该反应的摩尔选择性β≥80%,电流效率η_i≥75%,反应器表观电流密度i≥1500A/m~2.本研究为固定床电化学反应器内硝基苯电化学还原制备对氨基苯酚过程工业化奠定了重要的理论基础.     

Modeling of a continuous electrochemical tubular reactor for phenol removal

In this study, the treatment of highly polluted synthetic phenolic wastewater in a tubular continuous electrochemical reactor was modeled and solved by the finite difference method. The reaction conditions were previously optimized with batch reactor experiments, and the synthetic wastewater containing 443 mg/L and 3063 mg/L initial phenol concentrations was treated in the runs at 25°C with 120 g/L electrolyte concentration. For the model solution, the column was divided into 10 nodes in z-direction and 9 nodes in r-direction with the intervals j z=3.5 cm, j r=0.5 cm, and j t=10 s and 1.2 min for 443 mg/L and 3063 mg/L phenol feed concentrations, respectively. The results of the model solution correlated with the experimental data fairly well, which could be useful in the design and scale up of tubular continuous electrochemical reactors for phenol removal.     

氯醇化管式反应器的设计计算方法

根据氯醇化反应的特点，利用气液反应的双膜理论，导出了宏观反应速率式，结合管式反应器的流动模型，提出了一个简便、有效的反应器的设计计算方法     

RuO2/Ti阳极电化学氧化吸收氨废气

采用溶液吸收结合电化学氧化法处理氨废气。电化学反应器采用尺寸为φ35mm×350mm的管式玻璃反应器,内壁贴附不锈钢网作为阴极,反应器中心轴向设置有φ10mm×350mm的钌钛电极(RuO₂/Ti)棒作为阳极。电极浸没在吸收液中,含氨气体从反应器底部经气体分布器导入反应器。实验结果表明,与溶液吸收相比,溶液吸收结合电化学氧化可以更长时间保持较高的氨气去除率。由于RuO₂/Ti电极产生的有效氯的间接氧化作用,氨气在NaCl溶液比在Na₂SO₄溶液中的去除率更高。以NaCl为电解液时,酸性条件下更有利于氨气的吸收和降解,并且氨气的去除率随着电流密度的增加而增加。产物分析发现氨气在NaCl和Na₂SO₄溶液中被电化学氧化后,主要产物为氮气,也有少量氨转化为硝酸根离子。     

烷氧基化反应技术简介

对烷氧基化反应的釜式烷氧基化反应器、循环喷雾的Press烷氧基化反应器、喷射式回路反应器和连续管式反应器进行了介绍,对比了各自的特点。     

新型管式反应器在氨酸法复合肥生产中的应用

为降低生产成本、提高产品质量,对氨酸法复合肥生产反应器进行设计,提出"浓硫酸预稀释-氨酸反应-二次补水"三段反应模式的新型管式反应器。介绍新型管式反应器人员操作、参数设计及应用优点。新型管式反应器的应用和推广可极大程度地减少蒸汽的使用,生产成本较燃煤蒸汽费用还要低。     

A numerical study on the effects of acidic catalyst on the polymerization of nylon-6

The effects of acetic acid on the polymerization characteristics of nylon-6 are investigated in a reactor model that consists of a continuous flow stirred tank reactor (CSTR) and a tubular reactor connected in series. Mathematical models for the CSTR and the tubular reactor have been established and solved by numerical methods. In the CSTR, the monomer conversion and the molecular weights are increased as the feed acetic acid concentration is increased. In the tubular reactor, the acid acts as both a catalyst and a modifier for the polymerization reaction. The effects of the feed acetic acid content on the zeroth, first and second moments and the polydispersity index of the polymer have been discussed.     

Transient behaviour of encapsulated enzyme reactor systems

Mathematical models are developed for the transient behaviour of encapsulated enzyme reactor systems such as the continuous stirred tank reactor (CSTR) and the packed bed tubular reactor. The rate processes taking place in the encapsulated enzyme bed are approximated by using a combined rate control model of enzyme reaction and membrane diffusion. The change in transient substrate concentration is obtained by using the developed rate expression in the material balance over the substrate as a function of time for the CSTR and as a function of time and position for the packed bed tubular reactor. The effects of various parameters such as the enzymic reaction rate constant, Michaelis constant, diffusional resistance of membranes, and Peclet number on the substrate concentration distribution, which varies with respect to operating time, are investigated. This study affords insight into the transient operating characteristics of the encapsulated enzyme reactor system. The results should be useful in understanding the start-up performance of the reactor systems and to control such reactor systems at desired operating conditions.     

环管反应器内传热过程的数值模拟

为了对环管反应器内传热规律进行研究,在Euler-Euler双流体动量传递模型和环管反应器聚合传质模型的基础上,考虑了环管反应器内传热过程,建立了环管反应器传热数学模型,对工业烯烃聚合环管反应器内流动、传热和传质及聚合反应过程进行了研究。反应器内浆液温度的模拟值与工业现场值吻合,说明所建立的环管反应器传热数学模型是有效的。模拟结果表明,环管反应器温度与物料浓度存在不均匀分布。在上升段,温度分布呈中心对称,在弯管段不再呈中心对称,下降段的温度因弯管段的不均匀分布而不再呈中心对称分布;随着浆液入口速度或入口固体颗粒相体积分数的增加,环管反应器上升直管段,弯管段以及下降直管段温度降低;管壁冷却水温度不同,对环管反应器内冷却能力也不同,在反应器内相同的释放热量情况下,冷却水温度越低,对反应器内物料的冷却能力就越强。     

A Comparison Between Monolithic and Wire Gauze Structured Catalytic Reactors for CH4 and CO Removal from Biogas-Fuelled Engine Exhaust

The application of the wire gauzes as the catalytic supports can provide a number of advantages in biogas exhaust abatement. In this paper, a model of wire gauze structured reactor for biogas exhaust removal is proposed and model based calculations are performed to compare the wire gauze catalytic reactor with the classic monolith. The modelling bases on kinetic data experimentally obtained in a small-scale tubular reactor for cobalt and palladium (as reference) oxide catalysts doped with promoters (Ce, Pd). The heat and mass transfer characteristics of the wire gauze reactor are taken from the former studies by the authors. The simulations show that for assumed reactor parameters, a combination of the promoted cobalt oxide catalyst and the wire gauze support can give high conversion of methane and carbon monoxide.     

Flow modeling in electrochemical tubular reactor containing volumetric electrode: Application to copper cementation reaction

The aim of the present work is to study the electrolyte flow characteristics in a tubular reactor containing a volumetric electrode, acting as turbulence enhancer, applied in our previous works to copper removal by cementation process. The hydrodynamic behavior of the electrolyte within the reactor under study has been determined using the residence time distribution (RTD) experimentally determined by a pulse tracer technique.