含固体颗粒流体用安全阀自动冲洗装置的研究

发布时间：2018-03-02 18:45

本文选题：安全阀　切入点：在线冲洗　出处：《河北工业大学》2011年硕士论文　论文类型：学位论文

【摘要】：安全阀用于煤直接液化工业的油煤浆输送管路时,当安全阀泄压后,密封面上往往残存煤颗粒,使阀瓣和阀座间存在缝隙,造成阀门关不死,从而产生内泄漏,同时颗粒的存在会加剧阀瓣和阀座密封面的磨损,影响安全阀的密封性能。有效地清除密封面上的固相颗粒,是解决此问题的关键。为此本课题提出了一种含固体颗粒流体用安全阀的自动冲洗装置,并应用FLUENT软件的欧拉模型对冲洗过程进行了三维数值模拟,初步探讨了方案的可行性。通过对不含油源设备的在线冲洗装置冲洗过程进行模拟研究发现,对冲洗油管路与阀门连接管路的连接三通的角度进行合理地选择,设定了合理的冲洗油管路入口的压力,对阀门冲洗过程进行模拟计算发现,冲洗一定的时间后,密封面上的煤粉颗粒体积率低于10-6,可认为密封面已被冲洗干净。同时,分析了液固两相流在冲洗装置中的流动特点,讨论了由冲洗过程对油煤浆输送系统造成影响。对以气液式蓄势器为油源设备的冲洗结构进行了研究。在不同压力下,对连接蓄势器和安全阀入口管路的三通采用不同角度,分别对不同装置的冲洗过程进行数值模拟,分析了三通角度和蓄势器压力对冲洗过程的影响。冲洗一定时间后,阀瓣与阀座间颗粒相体积率低于10-6,且总耗油量在蓄势器出油容量之内,可认为上述装置能够完成对阀门密封面的冲洗。比较发现,相同压力下,60°斜三通装置对煤浆系统的影响最小,45°斜三通装置次之;不同压力下,45°斜三通装置可完成冲洗的压力较低,总耗油量及进入油煤浆体系的油量小,优于60°斜三通装置。
[Abstract]:When the safety valve is used in the pipeline of coal slurry transportation in the direct coal liquefaction industry, when the pressure of the relief valve is released, the coal particles are often left on the sealing surface, resulting in a gap between the valve disc and the valve seat, resulting in the valve not being closed and resulting in internal leakage. At the same time, the presence of particles will increase the disc and seat sealing surface wear, affecting the sealing performance of the relief valve, effectively remove the solid particles on the sealing surface, This paper presents an automatic flushing device for the safety valve with solid particle fluid, and uses Euler model of FLUENT software to simulate the flushing process. The feasibility of the scheme is discussed preliminarily. Through the simulation study on the flushing process of the on-line flushing device without oil source equipment, it is found that the angle of connection between the flushing tubing line and the valve connecting pipeline is reasonably selected, and the reasonable pressure of the inlet of the flushing tubing line is set up. The simulation calculation of the valve flushing process shows that the volume ratio of pulverized coal particles on the sealing surface is less than 10-6 after washing for a certain time, and the sealing surface has been flushed out. At the same time, the flow characteristics of liquid-solid two-phase flow in the flushing device are analyzed. The influence of washing process on coal slurry conveying system is discussed. The flushing structure of gas-liquid accumulator as oil source equipment was studied. Under different pressures, the flushing process of different devices was simulated from different angles to connect the accumulator and the inlet pipe of safety valve. The effect of the angle of three links and the pressure of accumulator on the flushing process is analyzed. After flushing for a certain time, the volume ratio of particle phase between disc and seat is lower than 10-6, and the total oil consumption is within the oil output capacity of the accumulator. It can be considered that the above device can complete the flushing of the valve sealing surface. It is found that the influence of 60 掳oblique three-way unit on coal slurry system is the smallest at the same pressure, and that 45 掳oblique three-way unit under different pressures has lower pressure to complete washing, less total oil consumption and less oil into coal slurry system. It is better than 60 掳oblique three-way device.
【学位授予单位】：河北工业大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH134

【引证文献】