关键词: font-family:-apple-system, blinkmacsystemfont, ", font-size:14px, background-color:#FFFFFF, ">催化裂化装置, 待生滑阀, 阀杆脱扣, 涡流, 磨损, 流速, 冲蚀, 仿真

Abstract: The reasons and solutions for the sudden rise and fluctuation of the settler material level from 41% during the adjustment process in a certain catalytic cracking unit are introduced. The analysis shows that the malfunction of the spent catalyst slide valve control caused the fluctuation of the settler material level. By removing the valve stem and control mechanism connecting block of the spent catalyst slide valve on-site, and adjusting measures such as rotating and pulling the valve stem, it is confirmed that the valve plate and valve stem are detached. Based on the analysis of the valve stem connection structure, measures such as adjusting the rotation and pulling of the valve stem were taken to restore the production of the device. A temporary top rod was installed on the 180° direction of the valve stem to work with the original valve stem to control the spent catalyst slide valve, ensuring the long-term operation of the device. In order to clarify the cause of the failure, a flow field simulation method was used to calculate the pressure cloud distribution, fluid velocity distribution, catalyst particle distribution, and control of the blowdown steam inside the slide valve. It was found that the flow control of the blowdown steam has a significant impact on the erosion at the valve stem connection. This conclusion was well verified during the maintenance.

Key words: font-family:-apple-system, blinkmacsystemfont, ", font-size:14px, background-color:#FFFFFF, ">FCCU, spent catalyst slide valve, valve stem detachment, eddy, wear, flow rate, erosion, simulation