聚丙烯细粉对生产的影响及对策

在聚丙烯生产过程中易产生较多细粉,细粉对生产过程产生较大影响,对生产过程中各影响因素进行了分析,探讨了产生细粉过多的原因,提出了预防细粉影响的措施和对策,较好地解决了聚丙烯细粉对生产过程的影响。     

Unipol气相流化床工艺聚丙烯细粉的分析

简介了广西石化公司生产四部20万t·a^-1聚丙烯装置的工艺。从催化剂设计制备、反应系统工艺操作、丙烯原料质量分析了聚丙烯细粉产生的原因,以及细粉过多带来的危害。通过提高丙烯精制效果、催化剂制备添加过程控制、反应系统优化操作等措施有效控制细粉的产生,降低细粉带来的危害,保证装置长、满、优运行。     

聚丙烯装置细粉产生的原因分析

从催化剂和工艺操作2方面分析了聚丙烯装置生产中细粉产生的原因,以及细粉过多时对生产的危害。结果表明,催化剂细粉含量高、运输、制备、破碎,汽蒸系统、干燥系统操作不当,反应器出口没加或少加失活剂是细粉产生的主要原因;细粉产生的过多,干燥效果差、风送系统运转困难、引起工艺系统的堵塞、影响设备的使用寿命。提出了相应解决办法及注意事项。     

CWP ZSK350挤压造粒机细粉产生原因分析及改进措施

在挤压造粒机日常运行过程中,各种因素导致切粒过程中产生大量聚烯烃树脂粉末,细粉过多会使后续干燥系统处理难度加大,怎样减少细粉的产生不仅有利于树脂粉料的损耗,降低产品单耗而且减少人工对细粉的打捞工作,既提高了化工企业经济效益,又降低了操作工的劳动强度,也相应的减少了环境污染的可能性。所以研究细粉的产生及减少措施具有重要意义。本文通过介绍挤压造粒机各部分组成,阐述了各部分的作用,分析了产生细粉的原因,提出了相对应的解决措施。     

环管工艺产生细粉的原因及标准处理方式

根据环管工艺法聚丙烯装置的工艺流程,分析了产品中产生过多细粉的原因、细粉在生产中的危害,并提出了相应的改进措施。     

聚丙烯装置汽蒸罐洗涤塔底产生细粉的原因及控制

液相环管法聚丙烯装置在生产中产生过多细粉是一个普遍的现象,给生产带来了影响设备运行等一些不利情况。结合装置实际情况和操作经验,从预聚合、催化剂种类、汽蒸喷射器C503堵塞、原料含杂质等方面分析了产生细粉的原因,并提出了一些控制细粉过多的措施。     

有效预防聚丙烯细粉产生的方法与措施

介绍了庆阳石化公司三联合运行部10万t/a聚丙烯装置从丙烯精制、催化剂制备、工艺操作三方面分析了细粉产生的原因,以及细粉过多对生产的危害。通过催化剂制备过程控制、优化操作条件、调整反应器出口失活剂等措施细粉得到有效控制,设备运行周期延长。     

聚丙烯装置中细粉产生的原因及改进措施

从催化剂和工艺操作方面分析了聚丙烯（PP）生产中产生细粉的原因,并说明了细粉过多对生产造成的危害,然后提出了以下改进措施：改进催化剂的配制方案、优化预聚反应器操作、提高原料丙烯质量等。     

聚丙烯装置生产中细粉过多原因分析及解决措施

本文分析了球形聚丙烯装置生产中细粉过多的原因，并提出相应的解决措施。     

环管聚丙烯装置生产中细粉产生的原因及对策

详细阐述了环管聚丙烯装置生产中细粉产生的原因以及细粉过多对装置造成的危害,并对如何减少细粉的产生提出了可行性建议,对环管聚丙烯装置的操作优化和工艺改进有一定参考意义。     

密相流化床中介尺度流动结构的流体力学特性研究

在一套流化床冷模实验装置中对黄沙颗粒和黄沙-硅微粉 （20 μm）混合颗粒进行实验。测量固含率时间序列信号并进行统计分析,提出并建立复杂光纤脉动信号的解耦方法,实现稠密气固流中介尺度流动结构的准确识别。基于统计矩一致性原理提出气泡阈值的计算方法,通过遍历法确定气泡阈值。对气泡阈值变化规律进行分析,发现加入细颗粒有助于改善流化质量,随表观气速的增加,气泡阈值减小。对气泡、乳化和聚团三相的相分率进行统计,发现在黄沙颗粒中加入少量（5%,质量分数）细颗粒能够显著改善流化质量,细颗粒添加量过多时（10%）,对流化质量的改善将减弱。对气泡的流体力学特性进行分析,发现加入10%硅微粉后,气泡弦长增大,频率降低,速度略有降低。对颗粒聚团流体力学特性进行分析,发现随硅微粉含量增加,表观气速对聚团速度的影响减弱,聚团弦长略有减小。加入5%硅微粉后,颗粒聚团的出现频率较小且径向上分布均一。加入10%硅微粉后,聚团频率有所增大,说明加入过多硅微粉会促进聚团的形成。     

DEPOSITION OF A FINE POWDER IN HORIZONTAL PIPELINES AND BENDS

The deposition of a very fine powder in a horizontal, lean-phase pneumatic conveying conduit containing a 90° bend has been studied experimentally. The total deposition and the deposition pattern were studied as a function of superficial gas velocity, solids loading and bend geometry: one sharp and three smooth bends of different radii of curvature were used. Most deposition was seen in the sharp bend, while in the smooth bends the deposition did not vary much with radius of curvature. The deposition decreased significantly with increasing superficial gas velocity. The experimental results were compared with CFD simulations of the flow field. The observations are consistent with the notion of deposition in regions with low near-wall gas velocity, indicating that models for deposition should be sought in considerations of the deposit stability for this type of system.     

Deposition of a fine powder in horizontal pipelines and bends

The deposition of a very fine powder in a horizontal, lean-phase pneumatic conveying conduit containing a 90° bend has been studied experimentally. The total deposition and the deposition pattern were studied as a function of superficial gas velocity, solids loading and bend geometry: one sharp and three smooth bends of different radii of curvature were used. Most deposition was seen in the sharp bend, while in the smooth bends the deposition did not vary much with radius of curvature. The deposition decreased significantly with increasing superficial gas velocity. The experimental results were compared with CFD simulations of the flow field. The observations are consistent with the notion of deposition in regions with low near-wall gas velocity, indicating that models for deposition should be sought in considerations of the deposit stability for this type of system.     

The effect of interstitial gas on milling. Part 2

In a previous paper results were presented on the effect of interstitial gas on the milling characteristics of one specific fine powder in a ball mill. This second paper gives more data on two other powders, cracking catalyst and hematite, together with those on the powder used in the earlier experiments, quartz sand. The effects found are similar for each of the three powders: increasing gas pressure or viscosity of the gas or both inside the mill increases the rate of breakage and decreases the fineness of the daughter particles of a milling event. The overall milling speed or production rate as well as the ultimate fineness of the product are both improved by increasing pressure or viscosity.On the basis of these results a comparison is made with wet milling. It appears that pressurized milling, pressure around 10 bar, is a good alternative for the milling of fine powders.     

优化操作方法减少PTA气送处理时间

针对聚酯生产中高压气送过程中经常出现的4个问题和难题,如PTA粉料下得过多,PTA粉料下落不畅,流化床堵和高压输送罐内压力高报始终不出现,提出了新的便捷的处理方法,提高了生产效率,并降低了劳动强度。     

The effect of interstitial gas on milling

In a research program on the influence of interstitial gas on the handling of fine powders, particle diameter less than 100 μm, the effect on milling is also investigated.The influence of the interstitial gas is exhibited through the drag force, due to velocity differences, which the gas exerts on the solid particles of the powder. These forces strongly influences the behavior of the powder.Our investigations of milling showed that the milling parameters, i.e. the specific rates of breakage and the breakage parameter, were dependent on the powder flow behavior. Two extremes were the regime of free-flowing powder, where the rate of breakage was high and the grinding of the individual particles was rather ineffective, and the regime in which the powder did not flow at all, where the rate of breakage was low, but where the grinding of the single particles was rather fine.     

阻垢分散剂在气化炉灰水系统应用

分析了四喷嘴对置式气化炉高温煤气洗涤水系统的结垢原因及阻垢分散措施,介绍了2种灰水阻垢分散剂的使用效果,并从投加量、药剂总消耗量和使用成本方面进行了比较。     

45万t/a合成氨装置合成气压缩机汽轮机启动过程出现的问题及对策

介绍了45万t/a合成氨装置合成气压缩机汽轮机的启动过程;分析了汽轮机多次启动失败的原因;针对汽轮机启动时振动过高及转速过低造成机组连锁跳车的问题,采取了相应的防范措施,达到了良好的效果。     

叶蜡石粒度对玻璃熔制的影响

通过实验研究了叶蜡石粒度对玻璃熔制的影响。研究结果表明:在无法控制超细粉质量分数的生产工艺下,叶蜡石粒度并非越细越好,当粒度做到325目全通时反而会导致玻璃熔化和澄清质量变差。叶蜡石超细粉的质量分数应控制在合理的范围内,大量超细粉的存在不利于玻璃的熔化和澄清,但少量超细粉的存在并不损害玻璃的熔制。