同向双螺杆挤出机在氯磺化聚乙烯生产中的工业应用研究

发布时间：2019-06-18 22:18

【摘要】：根据中国石油吉林石化公司电石厂氯磺化聚乙烯脱挥生产线由于受到设备能力限制,实际产能一直不能达到设计标准,制约了装置的竞争能力和发展空间的实际情况,本文研究了同向双螺杆挤出机在氯磺化聚乙烯脱挥造粒生产中的工业应用。本文采用数值模拟和实验研究相结合的方法,研究了同向双螺杆挤出机螺纹元件和螺杆组合对氯磺化聚乙烯橡胶脱挥效果的影响;对双螺杆挤出机脱挥生产线的工艺流程和操作参数进行了优化;通过相应的技术改造,成功地将同向双螺杆挤出机应用于氯磺化聚乙烯的工业化生产中,满足了产品质量稳定、长周期连续运行的生产要求。目前这套机组已经能够长周期运行和连续产出优等产品。研究工作取得以下主要成果:(1)对同向双螺杆挤出机捏合块结构的流场分析结果表明,氯磺化聚乙烯熔体的高压区位于捏合块螺棱的推进面,低压区位于螺棱的背面,由于压力差的存在,使氯磺化聚乙烯胶体中的挥发组分形成闪蒸,可快速脱除胶体中的挥发组分。捏合块结构的混炼过程以剪切流动为主,拉伸流动主要集中在啮合盘螺棱的推进面及背面剪切速率较低的区域。其中,当啮合块以KB1的方式排列时,更容易形成较大的压差,且流场中有更高比例的区域处于拉伸流动,因此有更好的脱挥效果。(2)实验结果表明,合理配置螺杆组合的同向双螺杆挤出机,有较好的脱挥效果,能够生产出实际生产中氯磺化聚乙烯橡胶的两个牌号(CSM30和CSM40)的优等品。随着机筒温度的增加,氯磺化聚乙烯中的挥发组分更容易被脱除;而增加螺杆转速,缩短了胶在机筒中的停留时间,残留挥发份呈逐渐升高趋势。(3)实验结果表明,切粒冷却方式对脱挥效果有一定的影响。采用水冷却方式微量水会进入到胶内,对脱除挥发份不利,而风冷却有利于脱挥。(4)通过采用同向双螺杆挤出机和适当的技术改造后,生产氯磺化聚乙烯的装置产量由原来的1000吨/年提高至2000吨/年,产品的优等品率达到了 80%,同时四氯化碳的消耗没有增加,使得环保排放达到了要求。通过提高产量和提升产品质量,不仅提高了经济效益和环保效益,而且提升了氯磺化聚乙烯产品的竞争力和生存力。
[Abstract]:According to the fact that the actual production capacity of chlorosulfonated polyethylene devolatilization production line in calcium carbide plant of Jilin Petrochemical Company of PetroChina has been unable to meet the design standard because of the limitation of equipment capacity, which restricts the competitiveness of the plant and the actual situation of development space, the industrial application of co-directional twin-screw extruder in chlorosulfonate polyethylene devolatilization granulation production is studied in this paper. In this paper, the effects of thread elements and screw combination on the devolatilization effect of chlorosulfonate polyethylene rubber were studied by means of numerical simulation and experimental research, and the technological process and operation parameters of the devolatilization production line of twin-screw extruder were optimized. Through the corresponding technical transformation, the co-directional twin-screw extruder has been successfully applied to the industrial production of chlorosulfonate polyethylene, which meets the production requirements of stable product quality and long cycle continuous operation. At present, this set of units has been able to operate for a long time and continuously produce superior products. The main results are as follows: (1) the flow field analysis of the kneading block structure of the co-directional twin-screw extruder shows that the high pressure zone of chlorosulfonated polyethylene melt is located on the propulsion surface of the kneading block screw edge, and the low pressure region is located on the back of the screw edge. Due to the existence of pressure difference, the volatile components in chlorosulfated polyethylene colloid form flash, and the volatile components in the colloid can be quickly removed. The mixing process of kneading block structure is mainly shear flow, and the tensile flow is mainly concentrated in the thrust surface of meshing disk screw edge and the region with low shear rate on the back. Among them, when the meshing blocks are arranged in the way of KB1, it is easier to form a larger pressure difference, and a higher proportion of the region in the flow field is in the tensile flow field, so it has a better devolatilization effect. (2) the experimental results show that the co-directional twin-screw extruder with reasonable screw combination has better devolatilization effect, and can produce two grades (CSM30 and CSM40) of chlorosulfated polyethylene rubber in the actual production. With the increase of cylinder temperature, the volatile components in chlorosulfated polyethylene are more easily removed, while increasing the screw speed shortens the residence time of glue in the cylinder, and the residual volatile matter increases gradually. (3) the experimental results show that the granulation cooling mode has a certain effect on the devolatilization effect. Using water cooling mode, trace water will enter into the rubber, which is disadvantageous to the removal of volatile matter, but air cooling is beneficial to devolatilization. (4) after adopting the co-directional twin-screw extruder and proper technical transformation, the output of chlorosulfonate polyethylene plant has been increased from 1000 tons / year to 2000 tons / year, and the excellent product rate of the product has reached 80%. At the same time, the consumption of carbon tetrachloride has not increased, which makes the environmental protection discharge meet the requirements. By increasing the output and product quality, not only the economic and environmental benefits are improved, but also the competitiveness and survivability of chlorosulfated polyethylene products are improved.
【学位授予单位】：华东理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ325.12

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