Hydrofining reaction – interruption of fresh hydrogen supply – emergency response procedures

Emergency response plan for new hydrogen supply interruption in the hydroprocessing unit. Job titles: Shift leader, Deputy shift leader. 1. Immediately report the new hydrogen supply interruption to the dispatch center and the unit management. 2. Notify the storage and transportation team to confirm that the interlock for the gas holder inlet valve has been activated, and that the bypass valve from the gas holder to the flare is open. 3. During the processing process, if a leak or fire occurs on site, immediately contact the dispatch team and inform the company’s fire brigade. Position title: Operator. Signature indicating completion: □ The reaction system should be cooled down immediately, and the main fuel gas cut-off valve of furnace F-101 should be activated to reduce the reaction temperature to 310°C. Notify the field operator to check the combustion of the permanent light in the heating furnace, and close the flow control valves and upstream manual valves for the two main fuel gas supplies. While cooling down, reduce the reaction feed rate accordingly to 300 t/h. □Contact the dispatching department as well as the upstream and downstream units, stop the fresh feed, and switch to a long-cycle operation for the tail oil. □After confirming that the amount of fresh hydrogen in the unit has decreased, notify the operator on site to shut down one unit K101; the operator inside the plant then adjusts the hydrogen supply based on the inlet pressure control system of D-107. □If the system pressure continues to drop, shut down HT-101 and HT-102, confirm that the inlet isolation valves for HT-101 and HT-102 are closed, and close the inlet flow control valves for HT-101 and HT-102. □Strictly prevent the liquid level in Hot High Pressure D-103 from reaching its maximum; maintain the level in D-103 at a low level (around 20%), and if necessary, divert the flow from D106 to the flare. Maintain stable levels and interfaces of the cold high-pressure liquid D-105, and strictly prevent high pressure from leaking into low pressure areas. □Close the main burner cut-off valve, flow control valve, and upstream manual valve of the fractionation heater. D-202 gas is diverted to the flare. □Stop steam supply to C-201 and C-202; redirect the steam in the convection section of the fractionator to vent. □The steam from each drum is diverted to vent. Position title: Field Operator. Signature indicating completion: □ Close the manual valve on the fuel gas pipeline leading to F-101, located next to the fuel gas separator tank, and confirm that the furnace in F-101 is completely extinguished. □Open the low-pressure flare valve at the top of D-202, and close the valve leading to F-201. Close the manual valve on the fuel gas main leading to F-201, which is located next to the fuel gas separator tank, and confirm that the furnace in F-201 has been completely extinguished. □Open the valve for directing the gas after low-pressure gas desulfurization to the flare, and close the valve that sends low-pressure gas to the PSA unit. □ Open the direct vent valves for the steam from D-901/902/903/904/905, close the valves that lead the steam from each drum to the steam distribution network, and redirect that steam to be vented. □According to the internal operation instructions, the diesel products and naphtha products were directed to the reject line. □Close the ORBIT valve at the outlet of the decommissioned compressor. □Manually set the shut-down pumps, fans, and air-cooled motors to the “stop” position, and simultaneously manually close the outlet manual valves of the pumps. □According to the internal operation instructions, close the manual valves upstream of each control valve. □Stop the ammonia lean liquid pump P-301A/B. It was used before; you can take it as a reference~~~~

There must be some discrepancies, such as the device tag number and the type of pump, but generally it follows this approach; it can be modified with just a few changes~~~~

Stop the feed, reduce the temperature at the furnace outlet, and enable large-scale circulation of the system.