塔板结构参数对负荷性能曲线的影响

通过对板式塔流体力学性能的分析，找出了板式塔塔板结构参数对负荷性能图中负荷性能曲线的影响关系，可用于指导板式塔的优化设计和改造。     

渗透蒸发膜改性技术的研究进展

物理改性和化学改性作为改变渗透蒸发膜的分离性能 (渗透通量和分离因子 )、抗污染性、物理化学稳定性的有效手段而吸引了大量的研究和开发兴趣。这些改性方法在不少场合下可以联合使用。对常用的改性方法进行了分类介绍 ,简要评述了各种方法的优缺点 ,并列举了一些实例加以具体说明     

国内外大型石油公司竞争力比较

入世后我国石油企业将面对国外大石油公司的竞争。要想在竞争中获胜，就必须提高我国企业的国际竞争力。标杆瞄准是目前国际上比较流行的提升企业竞争力的方法，本文从国内外大型石油企业的对比分析中，找到我国企业的不足，提出相应对策和建议。     

A transient method for characterizing flow regimes in a circulating fluid bed

In recent years, although an increasing number of literature have been devoted to circulating fluidized bed (CFB), the prediction of velocities over which different fluidization regimes exist is still difficult. In this study, a transient method was applied which readily allows one to identify operational features and critical transitions. The method is based on stopping the solids flow rate into the riser when riser is operating in fully dense transport regime. The analysis of transient pressure drop data across the riser during a solids flow cut-off experiment against its time derivative demonstrate the three distinct operating regimes that exist as the gas deplete the solid out of the riser. The transient was compared to data taken under steady state operations using statistically designed experiments. Results indicated that although there were significant differences when comparing operations in dilute conditions, there were no significant differences between the two methods in the fast fluidized and dense transport regimes. The transient method was capable of reproducing the solids circulation dependence on riser solids holdup and on the axial pressure profile. This transient method offers an accurate, easy, rapid, and reproducible means of characterizing CFB operations over a wide range of flow conditions. The lack of accuracy in the dilute regime is conjectured to be due to the wide particle size distribution that resulted in segregation during the transient testing.     

Static and dynamic studies of phase composition in a polydisperse system

We have conducted a study of the phase compositions of a ternary solution containing dextran/polyethylene glycol (PEG)/water using UV-visible spectrometry to study the equilibrium behaviour and confocal microscopy to study the dynamic behaviour observed when the system undergoes phase separation driven by the loss of water. Such a study of phase compositions using confocal microscopy is a new development of the technique. In the static experiments, we find a cloud curve, which lies above the coexistence curve on the PEG rich side of the phase diagram, this is found to be in qualitative agreement with calculations of the phase behaviour for a model polydisperse system. In the dynamic experiments, we are able to measure the phase composition using confocal microscopy in the late stages of separation. Here, the compositions lie well inside the coexistence curve at lower drying rates but converge with it at higher drying rates. This is linked to a change in phase morphology: at low rates, a droplet morphology is observed throughout the process whilst at high drying rates a gross phase separation into two layers is observed to occur even at the earliest times probed by the experiment.     

基于层次分析的FLANN神经网络研究及应用

针对传统函数链接型神经网络(functional link artificial neural networks,FLANN)不能有效处理化工过程中强耦合、带噪声的高维数据建模问题,提出了一种基于层次分析(analytic hierarchy process, AHP)的FLANN神经网络(AHP-FLANN)。通过层析分析模型过滤输入数据中的冗余信息,提取特征分量,并把提取的特征分量作为函数链接神经网络的输入进行建模。同时利用化工行业乙烯生产数据进行了验证,并和BP神经网络及FLANN神经网络进行了对比。结果表明,AHP-FLANN神经网络在处理复杂高维数据时具有收敛速度快、建模精度高、网络稳定性强等特点,同时能够指导乙烯生产,提高能效,具有良好的实用价值。     

PP装置扩能改造途径

通过对国内聚丙烯(PP)市场和生产企业现状的分析,指出现有PP装置需要并能够通过扩能改造来提高产量和竞争力;分析了装置扩能改造的各种途径;举例介绍了扩能改造技术的应用。     

我国GDP增长率走高将促进化纤工业持续增长

分析并指出了我国 1980 -2 0 0 0年国内生产总值 (GDP)增长率走高的主要原因是得益于扩大内需 ,调整经济结构 ,深化经济体制改革及加入WTO等 ;介绍了我国化纤发展概况 ,我国化纤产量与GDP同步增长 ,消费出口投资推动了我国化纤持续增长 ;提出充分利用好国际国内两个市场 ,两种资源 ,以提升我国化纤工业的整体竞争力。     

国产化大容量涤纶短纤维熔体直纺生产线简介

介绍了 10 0t/d国产化熔体直纺涤纶短纤维生产线的设备及工艺特点。该生产线采用中心吹风技术 ,串级蒸汽闪蒸系统 ,环形上油等新技术 ,生产的 1.5 6dtex× 3 5mm涤纶短纤维质量优良。     

拜耳法中石灰添加量对氧化铝溶出率的影响

在拜耳法高压溶出过程中，添加石灰可以改善氧化铝溶出的工艺过程，石灰添加量对氧化铝溶出率影响极大；最佳的石灰添加量可以获得较好的溶出效果。