乙烯装置膨胀再压缩机性能试验及评价

Performance test and evaluation of expander-compressor in ethylene plant

膨胀再压缩机是乙烯装置的核心设备,机组在高速、低温下运行,对设计、材料和轴承系统等方面的要求很高,目前严重依赖进口。膨胀再压缩机的性能试验是评价机组性能的重要手段,但关于膨胀再压缩机的性能试验还没有相关成熟标准指导。根据膨胀再压缩机的特点,对乙烯装置膨胀再压缩机性能试验的方案设计进行介绍,包括试验转速、试验气体、试验状态的设计以及试验结果的换算,并结合相似理论开发了试验结果核算程序。结果表明,机组试验等熵效率为82.55%,优于设计等熵效率,符合标准指标;为保证性能试验结果的可靠,试验设计和测试过程中应注意气体液化、流动相似等问题。利用相似理论设计的乙烯装置膨胀再压缩机性能试验方案和试验结果核算程序可以有效应用于工程领域。

Expander-compressor is the core equipment in the ethylene plant.Expander-compressor unit runs at high speed and low temperature,so it has high requirements for design,material and bearing system.At present,expander-compressor is highly dependent on imported units.Expander-compressor's performance test is an important method to evaluate the performance of the expander-compressor unit,but there is no relevant mature standard on this topic to refer to.In this paper,the expander-compressor's performance test scheme is introduced,including the design of test speed,test medium,test conditions and the conversion of the test results based on the machine characteristic,and a program used for the test result validation is developed based on the Similitude Principle.It shows that the test isentropic efficiency is 82.55%,which is higher than the design isentropic value,and the performance of this expander-compressor can meet the evaluation criteria specified in the standard.In conclusion,the designed performance test scheme and test result validation program using Similitude Principle can be effectively applied to the engineering field.