丙烯制冷系统换热器泄漏对乙烯装置的影响及对策

Effect and countermeasure of heat exchanger leakage of propylene refrigeration system on ethylene plant

对乙烯装置丙烯制冷系统换热器泄漏引起的乙烯精馏塔压力波动、丙烯制冷压缩机段间罐液位波动、碳二加氢出口冷却器温度异常等情况进行了分析,并采取相应的对策。结果表明:裂解气压缩机四段出口冷却器泄漏,导致含有水的裂解气进入丙烯制冷系统,引起制冷压缩机系统冻堵和冷剂组成变化;采取优化甲醇注入方案、置换丙烯冷剂、新增泄漏换热器水收集系统等措施后,有效降低了游离水进入系统引起冻堵的风险,保证装置安全平稳运行。

The problems caused by the leakage of the heat exchanger of propylene refrigeration system in ethylene plant were analyzed,including the pressure fluctuation of ethylene distillation column,the level fluctuation of the tank between different sections of propylene refrigeration and compression machine,and the abnormal temperature of carbon dioxide hydrogenation outlet cooler,and the corresponding solutions were put forward. The results showed that the frozen blockage and composition changes of the coolant system were caused by the leakage of the four-section outlet cooler of the pyrolysis gas compressor leading to the leakage of water-containing pyrolysis gas into the propylene refrigeration system;and the several measures were adopted, including optimizing methanol injection scheme,replacing propylene coolant,and adding a new water collection system to the leaky heat exchanger,the risk of frozen blocking caused by free water entering the system was reduced effectively,and the safe and smooth operation of the unit was guaranteed.