Regarding the over-temperature protection of hydrogenation reactors, the necessity of installing wall thermocouples, and under what circumstances they are required
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This post was last edited by 328104062 on 2018-4-16 00:04. As the title suggests: 1. Is it necessary to install an over-temperature protection interlock for the hydrogenation reactor, and does this depend on the properties of the feedstock? Is there a possibility of excessive temperature rise during the hydrogenation of straight-run feedstock? Is it necessary to implement cooling measures (cold hydrogen, cold oil)? For our straight-run diesel hydrotreating processes (with dew point reduction), no reactor temperature interlocks have been installed ； There is cold hydrogen in the middle part and at the inlet of the reactor. The straight-run kerosene hydrogenation reactor does not have a high-temperature interlock; although there is no cold hydrogen, the FCC gasoline hydrogenation reactor does have such an interlock. There is cold hydrogen in the middle part. 2. Is the necessity of installing thermocouples on the walls of the hydrogenation reactor determined by the operating pressure? What operating pressure is required to install wall thermocouples for temperature monitoring in order to prevent hydrogen embrittlement/hydrogen corrosion? Our straight-run diesel hydrogenation (with pour point reduction) operates at a pressure of 4.0 MPa, with wall thermocouples installed for temperature measurement. Catalytic diesel hydrogenation is carried out at an operating pressure of 9.0 MPa; wall thermocouples are used for temperature measurement. During startup and shutdown, the pressure can exceed 1/4 of the design pressure only when the wall temperature is above 93°C. During startup, the temperature is increased first followed by the pressure; during shutdown, the pressure is reduced first before the temperature is lowered. To protect the reactor, the operating pressure for the straight-run kerosene hydrogenation reactor is 2.0 MPa, and no wall thermocouples are installed for temperature measurement. The operating pressure for FCC gasoline hydrogenation is 1.8 MPa, with no wall thermocouples installed either. Manager’s discussion group
One of the main reasons for excessive hydrogenation temperature is the inability to remove the reaction heat in a timely manner, which results in a low space velocity. Increasing the circulation rate can solve the problem.
Our company specializes in ethylene glycol process packages; interlocks are required for the temperature of the hydrogenation reactor, and we use circulating hot water to remove heat.
The hydrogenation reactor is equipped with six sets of three-out-of-two interlocks; previously these were part of the DCS interlock system, but in accordance with the requirements of the State Administration of Work Safety, they are now integrated into the SIS.
Thank you for sharing; I’m eager to learn*:time::time::victory::victory:
There is usually a reactor over-temperature interlock