共查询到20条相似文献,搜索用时 93 毫秒
1.
聚丙烯环管反应器的模拟 总被引:6,自引:0,他引:6
以荆门石化总厂 7万t/a聚丙烯装置为基础 ,介绍了环管反应器特点 ,分析了物料在环管反应器中的流动特性 ,建立了符合其性能的数学模型。通过对模型的求解 ,得到了固含率、单体浓度、反应器温度、冷却水温度、聚合反应速率、链转移反应速率和催化剂失活速率等参数与环管反应器管长度的关系 ,为聚丙烯环管反应器的优化操作提供了理论依据 相似文献
2.
聚丙烯环管反应器的模拟 总被引:2,自引:0,他引:2
以荆门石化总厂7万t/a聚丙烯装置为基础,介绍了环管反应器的特点,分析了物料在环管反应器的流动特性,建立了符合其性能的数学模型。通过对模型的求解,得到了固含率,单体浓度,反应器温度,冷却水温度,聚合反应速率,链转移反应速率和催化剂失活速率等参数与环管反应器管长度的关系,为聚丙烯环管反应器的优化操作提供了理论依据。 相似文献
3.
为考察BCH催化剂的性能及扩展催化剂的应用范围,北京燕化高新技术股份有限公司与美国Phillips石油公司合作,在后者的聚乙烯环管中试装置上,对BCH催化剂进行了性能评价.试验证明,BCH催化荆应用于环管反应器中具有较高的活性;通过改进加料方式,聚合反应操作平稳;在生产高密度聚乙烯时,完全可以在Phillips环管工艺上使用BCH催化剂. 相似文献
4.
采用DQ-3催化剂,在液相本体双环管反应器中试生产了双向拉伸聚丙烯薄膜专用树脂T28C。生产中发现,催化剂氢调敏感性差、给电子体难计量、粒料和粉料熔体流动速率(MFR)偏差较大等问题。采用关闭第1环管反应器的氢气注入阀、只在第2环管反应器中加入氢气来合理分配氢气浓度;稀释给电子体浓度;在测试粉料MFR时适当加入抗氧剂,密切监控反应工况等方法解决了问题,生产出合格产品,且产品各项性能指标与国内同类产品相当。 相似文献
5.
环管反应器内传热过程的数值模拟 总被引:1,自引:0,他引:1
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。 相似文献
6.
Spheripol聚丙烯工艺生产过程中最大的风险因素之一是反应器温度过高,造成反应器内聚合物暴聚。因此,控制环管反应器的温度控制对Spheripol聚丙烯装置安全生产尤为重要。本文重点讨论影响环管反应器温度的因素,及环管反应器温度波动如何及时判断原因和采取相应调整措施。 相似文献
7.
8.
环管反应器轴功率波动,尤其为一环反应器轴流泵轴功率波动,此种现象在液相环管反应生产中表现尤为突出,并且一直困扰着聚丙烯行业,大庆30万t聚丙烯/年装置经首次开工成功后,至今已运行一年,期间多次出现环管轴功率波动现象,为此装置技术人员采取了多种措施,并进行了深入的分析. 相似文献
9.
高密度聚乙烯环管淤浆工艺生产过程中会出现黏壁现象,反应器的黏壁是普遍存在的问题,这也是多种因素相互作用造成的。低聚物的生成、聚合温度高、静电、共聚单体等都有可能使反应器产生黏壁现象。通过合理控制共聚单体浓度,控制反应温度,保持反应器内壁光洁度,控制反应器内固含量等方法,可有效减少反应器黏壁概率,延长装置的运行周期。 相似文献
10.
11.
A three-dimensional (3D) computational fluid dynamics (CFD) model, using an Eulerian–Eulerian two-fluid model incorporating the kinetic theory of granular flow, is adopted to describe the steady-state liquid–solid two-phase flow under conditions employed in a tubular loop propylene polymerization reactor composed of loop and axial flow pump. The model is validated by comparing its simulation result with the classical calculated data as well as a set of data collected from certain pilot plant in China. The entire flow behaviors and the effects of guide vane on them in the reactor are also investigated numerically. Especially, the whole field in the loop reactor with the guide vane is obtained via the above model. The results show that a guide vane weakens the turbulent intensity, reduces the component of the rotating velocity, and contributes to the uniform distribution of the particles in the reactor. The second flow phenomenon is successfully predicted in the loop reactor with the guide vane. 相似文献
12.
A non-isothermal, non-adiabatic fixed-bed pilot reactor specially designed for fast measurement of axial and radial temperature and concentration profiles during dynamic experiments is described. The pilot plant is interfaced to a process computer and facilitates conducting different types of dynamic experiments, such as those with simultaneous un-correlated periodic changes of the process variables. This type of dynamic experiments proved to be most efficient for collecting the data necessary for reactor modelling. Axial and radial temperature and concentration profiles in the fixed bed were measured during catalytic hydrogenation of toluene on an industrial nickel catalyst. Peak shaped perturbations were employed to study the parametric sensitivity of the reactor behaviour and to estimate the reaction kinetics. 相似文献
13.
E.A Naundorf D Subramanian N Räbiger A Vogelpohl 《Chemical Engineering and Processing: Process Intensification》1985,19(5):229-233
A newly developed loop reactor has been shown to treat various domestic and industrial waste waters highly efficiently. In pilot studies BOD5 capacities per unit volume as high as 28 kg m?3 d?1 have been achieved for domestic waste water. In treating the effluents from a paper factory the compact reactor gives the same degree of conversion for only 1/6 of the residence time of the factory's conventional effluent treatment plant. 相似文献
14.
15.
D. L. Keairns 《加拿大化工杂志》1969,47(4):395-397
A model of a continuous flow stirred tank reactor based on laboratory experiments successfully describes the behavior of a pilot plant reactor. This model simulates the pilot plant performance over the full range of operating conditions: at high impeller speeds where performance approaches that of a perfectly mixed reactor and at low impeller speeds where performance significantly differs from perfect mixing. The micro-mixed feed model divides the continuous flow stirred tank reactor into a small micro-mixed impeller zone and a large macro-mixer. 相似文献
16.
17.
Catalytic three-phase reactions including homogeneous liquid-phase steps were simulated in a loop reactor. The loop reactor consisted of a reaction vessel, an external loop as well as an ejector. The loop reactor was modelled using tanks-in-series or alternatively, axial dispersion models. Kinetics of the reductive alkylation of aromatic amines, which was determined from the experiments in a laboratory autoclave, was used for verifying the reactor model and for concentration profile simulations in the loop reactor. 相似文献
18.
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. 相似文献
19.
The fluid‐dynamic behavior of a circulating fluidized bed pilot plant for oxyfuel combustion was studied in a cold flow model, down‐scaled using Glicksman's criteria. Pressures along the unit and the global circulation rate were used for characterization. The analysis of five operating parameters and their influence on the system was carried out; namely, total solids inventory and the air velocity of primary, secondary, loop seal and support fluidizations. The cold flow model study shows that the reactor design allows stable operation at a wide range of fluidization rates, with results that agree well with previous observations described in the literature. 相似文献
20.
Nguyen Khac Tien Erwin Flaschel Albert Renken 《Chemical Engineering Communications》1985,36(1):251-267
An experimental investigation of thermal bulk polymerization of styrene in a pilot plant will be reported. The plant is composed of a recycle tubular reactor followed by a tubular reactor. The conversion of the pre-polymerization part is in the range of 0 to 60% and at the outlet of the pilot plant up to 96%. Studies on the residence time distribution show plug-flow behaviour for a variety of different conditions with respect to viscosity and density gradient. The polymers obtained are characterized by gel permeation chromatography and compared to commercial products. 相似文献