Blockage at the outlet pressure of the coking heater
Thread Content
In coking units for the comprehensive utilization of residue oil, the pressure at the outlet of the heating furnace often gets blocked. The pipe slopes upward, with the pressure measurement point located at a horizontal position on the right side of the pipe. After it became blocked, pressing the hand pump to 60 KG had no effect at all. 3 furnaces with 6 points; 2 shutdowns for repairs were required, both times the pressure guide tubes had to be cut – the first time behind the root valve, and the second time in front of it. It needs to be transferred electrically; one person operates it while another holds it from behind in order to make it work. The next time it’s turned on, if it gets blocked again, I won’t know where to make the cut :L Although it hasn’t happened three times yet, I’ve already resigned due to this issue; it has troubled me for a long time. I’m asking fellow users if there are any good ways to solve this problem.
It seems that this issue can be resolved using a static pressure purging system for the blast furnace body; that is, nitrogen is blown into the interior while measuring the pressure in order to prevent blockages. If you need any information, feel free to contact me!
Change to single-flange pressure capillary manometer tube
Our plant’s coking unit is equipped with an isolation fluid system; the pressure transfer tubes of the transmitters that are prone to blockage have their isolation fluids flushed regularly, so severe consequences like those you described basically do not occur. You might also consider installing an isolation fluid system.
The isolation fluid system and the backwash system are both in use on a regular basis, but they don’t have much effect at the outlet of the heating furnace; there are no problems in other areas. As for the single-flange type, it seems that its operating temperature range is not sufficient, as the temperature at the outlet of the heating furnace is usually around 495 degrees
Patent application number: CN200420096640.9 Date of patent application: 2004.09.29 Name: A remote-transmission flange diaphragm box for measuring the pressure of high-temperature media Publication (announcement) number: CN2755587 Date of publication (announcement): 2006.02.01 Category: Physics Date of grant Priority: Application (patent right) by Liu Dawei Address: 5-102, Building 6, Yongshi Living Area, Linzi District, Zibo City, Shandong Province 255400 Inventor (designer): Liu Dawei International application: International publication; Date of entry into ** Patent agency: Agent: Abstract: A remote-transmission flange diaphragm box for measuring the pressure of high-temperature media, comprising a base (1), a separation diaphragm (2), a filling fluid (3), and capillaries (4); it is characterized in that a piston limit valve (5) and a one-way valve (9) are installed on the base (1), with the side outlet of the piston limit valve (5) being connected to the inlet of the one-way valve (9) through a conduit (8). This remote-flange diaphragm box effectively prevents the isolation diaphragm from bulging beyond acceptable limits or suffering permanent deformation due to excessive expansion of the filling fluid when measuring the pressure, differential pressure, or level of high-temperature media. This helps to protect the instrument from damage and ensures accurate measurements. Main entry 1. A remote-flange diaphragm capsule for measuring the pressure of high-temperature media, comprising a base (1), a separation diaphragm (2), a filling fluid (3), and capillaries (4); characterized in that: a piston limit valve (5) and a check valve (9) are installed on the base (1), and the side outlet of the piston limit valve (5) is connected to the inlet of the check valve (9) through a conduit (8).
I think it’s fine to choose a thicker pressure guide tube
Replace the root valve with a flushing valve, equipped with a flushing ring.
Then what I said, using nitrogen for purging and then measuring the pressure online, that method definitely works
Firstly, backwashing can be increased, requiring the pressure of the solvent oil to be higher than the pressure inside the pipeline. A continuous purging method is employed. The second sampling line should be cut off as much as possible. At the same time, heat tracing and insulation should be increased. To determine the solidification temperature of residue, high-temperature steam can be used for heating.