延迟焦化装置放空瓦斯改入富气压缩机的工艺选择及分析

延迟焦化装置焦炭塔放空过程中的介质主要为放空瓦斯和水蒸气，这些介质中携带有焦粉和硫化物。为避免这些焦粉和硫化物造成干气低分气单元的设备堵塞和管线腐蚀等问题，炼油厂决定将焦化装置的放空瓦斯改入焦化富气压缩机。工业应用结果表明：焦粉携带过多会堵塞分馏塔塔顶空气冷却器管束，还会影响水冷却器的传热，需要跟踪检测；对焦化富气压缩机操作没有明显影响，但是富气压缩机振动值和主密封气流量略有上升；未对放空和冷焦速率造成影响，当放空冷却塔塔顶压力接近分馏塔压力时，要及时将放空瓦斯改入低压火炬系统；制氢解吸气可以通过转化炉完全消耗，同时，干气低分气单元干气压缩机冷却器由以前的一个月清理一次延长至目前的四个月未清理，实现了干气压缩机的长周期运行。

PROCESS SELECTION AND ANALYSIS OF CHANGING VENTING GAS INTO WET GAS COMPRESSOR IN DELAYED COKING UNIT

The main media in the coke drum venting process in delayed coking unit are venting gas and steam, which contains coke powder and sulfides. In order to avoid the blockage and pipeline corrosion of dry gas low pressure separator caused by coke powder and sulfides, the refinery decided to enter the venting gas of coking unit into coking wet gas compressor. The industrial application results showed that excessive coke powder blocked the tube bundle of air cooler at the top of fractionator, and also affected the heat transfer of water cooler, which needs tracking detection; no obvious impact on the operation of coking wet gas compressor was found, the vibration value of the compressor and the flow rate of main seal gas only slightly increased; the venting and coke cooling rate were not affected. When the pressure of the vent cooling tower was close to that of the fractionator tower, the venting gas should be changed into the low-pressure flare system in time; the desorbed gas could be completely consumed through the converter; At the same time, the cleaning frequency of dry gas compressor cooler in the low-pressure dry gas separation unit was from once a month to more than 4 months, which realizes the long-term operation of dry gas compressor.