The discharge valve of the waste catalyst tank in the fourth cyclone of the catalytic cracking unit is frequently replaced
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After being in use for a period of time, the valves on the waste agent unloading line under the four rotors fail to close properly due to catalyst wear, requiring frequent replacement. How can this problem be solved?
When Exclusion, open the root valve fully and use the second valve to control the flow rate; this will cause erosion of the second valve. To avoid frequent erosion, a large orifice plate can be placed between the two valves to regulate the erosion rate
Agree with the opinion above; we do it in the same way
Have you installed orifice plates in your valves? What size is appropriate?
Recommended method for determining the orifice diameter: 1. Based on the diameter of the pressure-bearing pipeline between the catalyst intermediate tank and the agent discharge valve, maintain a flow rate of around 10 m/s during agent discharge in order to minimize pipe wear. 2. Using this corresponding flow rate, and referring to the calculation methods for critical nozzles, determine the orifice diameter of the agent discharge orifice plate. 3. The fluid at this orifice plate also reaches the critical flow velocity. The temperature is only slightly lower than that upstream of the critical nozzle. For example, if the pressures upstream and downstream of the nozzle are 0.31/0.01 MPaA, the temperature upstream of the nozzle is 200°C, and the diameter of the pipe in the line for discharging the fluid is DN150, then when the nozzle diameter is 25 mm, the flow velocity in the pipe is approximately 12 m/s. Regarding the position of the orifice plate, since the flow velocity downstream of the orifice plate reaches the critical value, this can easily cause wear on the pipes or valves; therefore, it is advisable to expand the pipe diameter downstream of the orifice plate in order to reduce the flow velocity. Moreover, even if a valve is installed downstream, there should be a certain distance between it and the orifice plate. 6. In my opinion, it is not very useful to install valves downstream of the orifice plate; it is better to have dual valves upstream of the orifice plate. When removing the medium, these valves should be opened fully so that the entire pressure drop is borne by the wear-resistant orifice plate. The valve disc cannot withstand high-speed erosion.
Have you installed orifice plates there? What is the effect, and how often should the valves be replaced?
No, we operate the root valve at full open, with the second valve controlling the speed
No, we operate the root valve at full open, with the second valve controlling the speed
Replacing it with a wear-resistant ceramic valve will do. 18753503921