Explanation of catalytic interlock logic

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I. Booster interlock: 1. Interlock content: 1) The booster stops, and the bypass valve opens； 2) Interlock alarm for booster shutdown. 2. Chain projects: 1) When both boosters are shut down, and the “Booster Shutdown Bypass” switch is in the “Normal” position. 2) The manual interlock switch for the booster is activated. 3. Interlock reset: Once the interlock signal is normal, activate the interlock reset. II. Main fan interlock: 1. Interlock content: 1) Close the standby slide valve ； 2) Close the regeneration slide valve ； 3) Close the MIP inclined tube slide valve ； 4) Close the one-way damping valve of the main air supply pipe ； 5) Open the primary steam accident valve again ； 6) Open the secondary main steam accident steam valve ； 7) Activate the reaction feed interlock. 8) Interlock alarm for the regenerated section. 2. Interlock items: 1) The main fan and standby fan are shut down or operating safely, with the bypass switch in the normal position ； 2) Enable manual interlock ； 3. Interlock reset: Once all interlock signals are normal, activate the interlock reset. III. Automatic protection for low main air flow: 1. Interlock details: 1) Close the standby slide valve ； 2) Close the regeneration slide valve ； 3) Close the MIP inclined tube slide valve ； 4) Close the one-way damping valve of the main air supply pipe ； 5) Open the primary steam accident valve again ； 6) Open the secondary main steam accident steam valve ； 7) Activate the reaction feed interlock. 8) Interlock alarm for the regenerated section. 2. Interlock items: 1) Repeatedly low main air flow rate (≤### NM3/min) (two-out-of-two logic) and the bypass switch is in the normal position ； 2) The secondary main air flow is extremely low (≤### NM3/min) (taking the lower of the two values), and the bypass switch is in the normal position. 3. Interlock reset: Once the interlock signal is normal, activate the interlock reset. IV. Feed self-protection: 1. Interlock content: 1) Close the lift pipe feed self-protection valve ； 2) Close the riser quench oil control valve ； 3) Close the re-refining oil control valve ； 4) Close the recycle slurry control valve ； 5) Close the pre-lift dry gas control valve ； 6) Open the accident feed bypass valve ； 7) Open the feed atomization steam control valve ； 8) Open the slurry atomization steam control valve ； 9) Open the lift pipe steam control valve ； 10) Open the pre-lift steam control valve ； 11) Interlock alarm for the reaction section. 2. Interlock items: 1) Manual interlock switch for the reaction section ； 2) Interlock signals for the regenerated section. 3. Interlock reset: Once the interlock signal is normal, activate the interlock reset. V. Instructions: 1. Whether it is the main wind signal or the main fan signal, once either one meets the interlock condition, the interlock action will be triggered ； 2. The valve equipped with an interlock regulator cannot be adjusted before the interlock is reset ； 3. The booster, fans, and the primary and secondary air streams are each equipped with bypass switches, which are used to disable interlocks during instrument calibration. Explanation of the interlock logic for the waste heat boiler I. Logic for shutting down the fuel system of the waste heat boiler 1. Interlock actions: 1) Close the fuel gas inlet isolation valve 2) Disable the igniter signal 2. Trigger conditions for the interlock: 1) Superheater outlet temperature is too high (≥450°C) ； 2) Superheater outlet pressure is extremely high (≥4.2 MPa) ； 3) Vessel package level is high (≥90%) ； 4) Low low drum level (≤15%) ； 5) Fuel gas pressure is very low (≤0.05 MPa) ； 6) High furnace temperature (≥900°C) ； 7) Furnace fire suppression (fire suppression via two flame detectors simultaneously) ； 8) Fan shutdown (shutdown of any fan) ； 9) Manual emergency stop. 3. Interlock reset: Once all interlock signals are normal, the interlock allows for a reset. 4. Instructions: 1) When any one of the interlock conditions is met, the bypass switch will operate in its normal position as a result of the interlock mechanism. 2) The interlock is equipped with a bypass switch for instrument maintenance ； 3) The manual emergency stop takes precedence over the bypass signal. II. Ignition system interlock 1. Interlock content: The igniter is allowed to ignite. 2. Interlock items: 1) The drum liquid level is normal (<40%, >15%) ； 2) The fuel gas pressure is normal (>0.05 MPa) ； 3) Fan operation (either fan in operation) delays by 5 minutes ； 3. Note: The igniter is permitted to ignite only when all of the above three conditions are met. III. Interlock for boiler feed water pump 1. Interlock content: Start the standby pump 2. Interlock conditions: Low low boiler feed water pressure (≤5.3 MPa) and the bypass switch being in the normal position. IV. Automatic start of the blower: The outlet pressure of the blower is very low (≤4.5 KPa) and the bypass switch is in the normal position. V. Boiler interlock issues: 1. The fuel cut-off interlock activates whenever any fan stops, causing unnecessary disruptions in operation ； 2. Shutting down any fan cuts off the fuel, which is in conflict with the automatic startup of the standby unit and the interlock that permits ignition.