有限元方法求解化学气相淀积反应器模型(Ⅱ)——热壁反应器模型及反应器中流动及传递过程的分析

分析了热壁化学气相淀积反应器在流型、温度和浓度分布以及淀积速率等方面与冷壁反应器的异同,探讨了流动特性、传递过程和反应器几何尺寸对淀积过程的影响,为淀积不同薄膜时反应器的选型及设计提供了方法和依据.     

有限元方法求解化学气相淀积反应器模型(Ⅱ)——热壁反应器模型及反应器中流动及传递过程的分析

分析了热壁化学气相淀积反应器在流型、温度和浓度分布以及淀积速率等方面与冷壁反应器的异同,探讨了流动特性、传递过程和反应器几何尺寸对淀积过程的影响,为淀积不同薄膜时反应器的选型及设计提供了方法和依据.     

浅谈石化行业加氢反应器的设计要点及损伤对策

加氢装置广泛应用于石油工业,加氢反应器是其核心设备,其对石油行业的安全生产有着重要影响。加氢反应器长期工作在临氢高温高压的工况下,因此对材料的要求较高,技术难度较大。从热壁加氢反应器设计条件、主体材料的选择、构成部分、损伤对策等方面进行了分析,为今后的热壁加氢反应器设计提供理论基础。     

热壁加氢反应器制造及最后一道环焊缝现场焊接的安全质量控制

热壁加氢反应器制造监督检验重点和热壁加氢反应器最后一道环焊缝现场焊接方法及质量控制。     

热壁加氢反应器的无损检测技术

热壁加氢反应器是一种具有复杂结构的设备,对热壁加氢反应器的无损检测方法进行分析和探讨,具有一定的指导意义.     

热壁加氢反应器的检验技术

阐述了热壁加氢反应器的结构特点及一般选材,对制造、使用过程中可能出现的腐蚀、材质裂化、裂纹及其他损伤情况进行了归纳,对损伤产生的原因、防止或减少损伤发生的方法进行了总结。重点论述了热壁加氢反应器的检验技术,根据基层和内衬层的材质、结构特点,对无损检测方法分别进行了总结,最后对风险检验技术在热壁加氢反应器检验的应用进行了介绍。     

甲醇制氢反应器的一维模拟及工况分析

在温度220-280℃、液空速0．8-2．0h^-1、压力1．3-2．7MPa条件下，于无梯度反应器中测定了ALC-1A型双功能催化剂工业颗粒的宏观反应速率，得到了以速度表示的甲醇裂解重整多重反应的双速率宏观动力学方程。建立了甲醇裂解重整制氢工业管式反应器的一维拟均相数学模型，以工业反应器结构尺寸和操作数据为基准计算出计入壁效应及催化剂失活的活性校正因子。考察了不同的原料液配比、系统压力、液空速、壁温及进口温度下甲醇的转化率、氢气的时空产率和床层出口温度的变化。结果表明在一定范围内，降低甲醇在原料液中的含量，提高压力，选择适当的液空速和壁温，将有利于提高反应器的操作性能：单纯提高床层进口温度对反应几乎没有影响。     

温度和湿度对发射药自燃的影响

为了解环境温度和湿度对发射药热自燃规律的影响,以某单基发射药为例,在实验室中进行小型实验.采用均热块模拟加热、加湿法,选用不同直径的反应器,改变反应器中发射药所处环境温度和湿度,得到温度-湿度-自燃时间数据.结果表明,均热块温度越高,单基发射药的自燃时间就越短;当均热块温度一定,绝对湿度从相对较小值逐渐增大时,单基发射药的自燃时间先是变短,当达到最小值后又逐渐变长,直到发射药不自燃.表明湿度对单基发射药自燃规律的影响显著.     

聚合釜粘壁后的工艺控制及调整措施

聚合反应器粘壁,不但影响反应器生产能力,而且也影响产品质量和原材料单耗。通过工艺调整,可减缓聚合反应器粘壁程度,并可在一定程度上消除对产品质量的影响。     

自热制氢反应器研究进展

介绍了同心圆式反应器、板式反应器、壁反应器、微通道反应器在自热重整反应制氢中的特点。同心圆式反应器的传热是控制步骤,为强化传热而开发了空间形状不同和流体经过反应器不同腔体的先后顺序不同的反应器;板式反应器易于组装、拆卸和放大,而且热效率也比较高,是目前十分活跃的研究领域,重点在于操作参数和设计的优化及其高效壁载制氢催化剂的研制;壁反应器的反应表面和换热表面不分离,具有较高的热量耦合效果;微通道反应器具有优越的传热性能,但对加工和流体的性质有比较苛刻的要求。另外,不同燃料制氢机理的研究及其过程参数的稳态、瞬态模拟,为反应器的设计提供了理论依据。而制氢过程并行单元的研究为系统的集成奠定了基础。最后,指出开发板式壁反应器以及开展其在CO变换、净化方面的研究有较好的发展前景。     

Modeling of a Reverse Flow Reactor for Methanol Synthesis Modeling of a Reverse Flow Reactor for Methanol Synthesis

An accurate one-dimensional, heterogeneous model taking account of axial dispersion and heat transfer to the reactor wall, and heat conduction through the reactor wall for methanol synthesis in a bench scale reactor under periodic reversal of flow direction is presented. Adjustable parameters in this model are the effectiveness factors for each of the three reactions occurring in the synthesis and a factor for the bed to wall heat transfer coefficient correlation. Experimental data were used to evaluate these parameters and reasonable values of these parameters were obtained. The model was found to closely predict the reactor performance under a wide range of operating conditions, such as carbon oxide concentrations, volumetric flow rate, and cyclic period.     

Dynamics of a continuous stirred tank reactor for styrene polymerization initiated by a binary initiator mixture. II: Effect of viscosity dependent heat transfer coefficient

The dynamic behavior of the solution polymerization of styrene in a continuous stirred tank reactor is analyzed with a mixture of tert-butyl perbenzoate and benzoyl peroxide as an initiator system. In the modeling of the reactor, a viscosity dependent reactor wall heat transfer coefficient is used to account for the changing heat transfer efficiency as monomer conversion and polymer molecular weight increase. The steady state and bifurcation behaviors have been investigated with the reactor residence time, initiator feed composition, initiator concentration, feed solvent volume fraction, and coolant temperature as bifurcation parameters. Unlike the reactors with constant heat transfer coefficient, the present system exhibits relatively simple steady state and dynamic bifurcation behaviors. Oscillatory behavior is observed only when the solvent volume fraction in the feed exceeds 0.2. The dynamic simulation of the reactor also indicates that a feedback temperature controller may fail to maintain the reactor temperature when the heat transfer coefficient changes as a result of process disturbances.     

绝热固定床反应器的研究——(Ⅱ)床内定态温度分布

本文运用一维非均相动态模型,研究了绝热固定床反应器床内定态温度分布问题.由于床内温度分布直接关系到反应器内高温区长度,因而对温度分布影响因素的研究甚为重要.本研究分别阐明了催化剂层、气体及器壁导热对床层温度分布的影响,并以实例予以说明.研究表明,实验型反应器器壁导热的影响不容忽视,因而将实验数据用于放大时必须考虑器壁导热的影响.     

Trickle bed reactor model to simulate the performance of commercial diesel hydrotreating unit

A two phase mathematical model was developed to simulate the performance of bench scale and commercial hydrotreating reactors. Major hydrotreating reactions, namely, hydrodesulphurization, hydrodearomatization and olefins saturation were modeled. Experiments were carried out in a fixed bed reactor to study the effect of different process variables and these results were used for estimating kinetic parameters. Significant amount of feed vaporization (20–50%) was estimated under normal operating conditions of DHDS suggesting the importance of considering feed vaporization in DHDS modeling. The model was validated with plant operating data, under close to ultra low sulphur levels by correctly accounting for feed vaporization in heat balance relations and appropriate use of hydrodynamic correlations. The model could predict the product quality, reactor bed temperature profiles and chemical hydrogen consumption in commercial plant adequately.     

STUDIES OF ADIABATIC FIXED-BED REACTORS (Ⅱ) STEADY-STATE TEMPERATURE PROFILES

One-dimensional heterogeneous model has been used for studying steady-state temperature profiles in adiabatic fixed-bed reactors.Since high temperature zone is determined by the temperature profile in the reactor, it is obviously of primary importance to study the effects affecting the steady-state temperature profiles. This paper shows how heat conductance of the packed catalysts, gas mixture and the reactor wall affect the temperature profile, and, a numerical example is given for illustration. It is indicated that the heat conductance of the laboratoryscale reactor wall is considerable and its effect is not negligible during scaling-up.     

环氧乙烷合成反应器数学模拟

针对扬子石化公司乙烯氧化制环氧乙烷工业规模的壁冷式固定床反应器,在YS-6型银催化剂宏观动力学模型的基础上加以修正,获得了YS-7型银催化剂宏观动力学模型,建立了环氧乙烷合成固定床反应器的一维拟均相模型.通过模型计算值与工业生产实际值的比较,发现两者相差很小,从而验证了反应器模型和所用的宏观动力学模型的准确性,可用作扬子石化公司环氧乙烷合成反应器的模拟与操作优化.     

Simulation of a Reverse Flow Reactor for the Catalytic Combustion of Lean Methane Emissions

This work is focused on the performance prediction of pilot scale catalytic reverse flow reactors used for combustion of lean methane-air mixtures. An unsteady one-dimensional heterogeneous model for t...     

Design of a Flexible Pilot Plant Reactor for the Steam Cracking Process

A design technique for a pilot plant reactor of single diameter is presented to scale up or down steam cracking coils of different configurations like mono‐tubular, classical, and reversed splits. Using dimensional analysis, two criteria are selected in establishing partial similarity between different scales, the mean residence time, and the axial pressure profile in the reactor, in addition to preserving the flow pattern within the turbulent region. The sensitivity and accuracy of the proposed method is compared to another conceivable alternative that focuses on the lateral gradients. The pilot reactor coil is adapted for any large‐scale reactor by the adjustment of feed flow rate and the effective length exposed to the firebox heat flux. Simulation results for naphtha cracking in a commercial split coil and also the equivalent pilot plant reactors are used for verification and validation of this method.     

Process heat integration of a heavy crude hydrotreatment plant

The present paper focuses on the study of process alternatives for heat integration of a heavy crude oil hydrotreatment plant. Experimental information obtained from a pilot scale, kinetics and reactor modeling tools, and a commercial process simulator were employed to develop mass and energy balances. Four study cases, which employ a combination of quenching and heat exchangers, were identified and evaluated. The results indicated that the case with two quenches with hydrogen and three heat exchangers is the best process heat integration (PHI) option from an energetic point of view.     

超临界水氧化技术工业化的瓶颈问题及解决方法

超临界水氧化技术作为一种绿色环保技术,在处理有毒、难降解和高浓度有害物质上有众多优势,且目前其应用基础已经形成,国外也有实际的工业应用之例。但是超临界水氧化反应器的腐蚀和结垢问题,以及超临界水氧化的高能耗、高费用的问题严重阻碍了该技术在工业生产中的推广和发展,成为制约其工业化的瓶颈问题。本文综述超临界水氧化过程中的反应器的腐蚀和结垢问题、反应热问题,同时指出当前解决这些问题的方法。此外还列举了目前采用超临界水氧化技术的单位以及其所采用的反应器类型。