脱乙烷塔回流泵气蚀原因分析及对策

Analysis of the Causes and Countermeasures of Air Erosion in De-ethane Reflux Pump

塔里木油田轮南轻烃厂投产初期,脱乙烷塔回流泵就无法正常启动,严重影响丙烷收率提高。为了解决脱乙烷回流泵无法启动的问题,通过对泵体安装高度、实际工况与设计工况对比,回流罐液相除气能力核算以及对回流泵与回流罐的内部结构分析,发现现场实际工况与设计工况不符、取温点不合适、回流罐内部结构设计是主要影响因素。后期通过更换耐气蚀能力更高的泵型,成功解决脱乙烷塔回流泵无法正常运转问题。在气液相负荷均很高的回流罐设计选型方面,建议严格按照气液分离器进行相关计算,并合理考虑气液相分布不均、外部干扰等因素对分离效果的影响,内部合理选型并布置入口粗分离器、波纹板聚结器等内购件,可提高低温液烃脱气效果,改善泵运行工况。

In the early stage of operation of zhannan light hydrocarbon plant in Tarim oil field, deethane tower reflux pump could not be started normally, seriously affecting the yield of propane. In order to solve the problem that the deethane backflow pump can not start, through the installation height of the pump body, the comparison of the actual working conditions with the design conditions, the calculation of the phase degassing capacity of the reflux tank, and the analysis of the internal structure of the backflow pump and the backflow tank, It is found that the actual working conditions of the site are inconsistent with the design conditions, the temperature point is not suitable, and the internal structure design of the reflux tank is the main influencing factor. In the later period, by replacing the pump type with higher air corrosion resistance, the problem that the deethane tower backflow pump can not operate normally was successfully solved. In the design and selection of reflux tanks with high gas-liquid phase load, it is recommended to strictly follow the calculation of gas-liquid separators, and reasonably consider the influence of uneven distribution of gas-liquid phase and external interference on the separation effect. The internal reasonable selection and layout of the inlet thick separator, corrugated board condenser and other internal purchasing parts can improve the low temperature liquid hydrocarbon degassing effect and improve the pump operation conditions.