Questions regarding the design of safety relief devices for molecular sieve towers in the pressure-reduction regeneration process

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I have a question to discuss with everyone: regarding the two pressure-reduction regeneration processes in dry dehydration. Pressure: 3.8 MPa at 30°C; absorption conditions: a safety valve set pressure of 4.2 MPa is considered. Regeneration mode: operating pressure of 0.3 MPa, temperature of 240°C. In the fire scenario, the valve is designed to maintain its position, and the safety valve at the outlet of the regeneration gas heater is used to protect the equipment in this section. The setting pressure for this safety valve is 0.48 MPa; at this pressure, the discharge volume of the safety valve is less than the volume of the regeneration gas circulating through the system. This safety valve is selected based on the assumption of accidental valve closure. Cold blowing condition: operating pressure of 0.3 MPa, temperature between 220~30°C. In the case of a fire, the valve is used to maintain its position; the regenerated gas is cooled to 60°C after leaving the tower, and no water is separated from it, so it is sent directly out of the system as fuel gas. In such a situation, the safety valve designed to activate at 4.2 MPa should no longer be able to protect the tower. So how should the safety relief valves of the equipment in this type of condition be considered? I asked everyone for advice; thank you.