What are the main tasks for operators during an emergency shutdown in oil refining and coking?

Major accidents that require emergency shutdown measures: (1) Prolonged and widespread power outages; interruption of power supply to the equipment. (2) Disruption of water supply (fresh water, softened water, deoxygenated water, circulating water). (3) A serious accident occurs in the device, threatening its safe operation. Emergency shutdown procedure: (1) Immediately inform the plant dispatcher and the shift crew. (2) Emergency shutdown of the heating furnace: close the valves upstream (or downstream) of the temperature control valve to reduce the temperature. (3) Stop feeding the furnace and blow steam into the furnace tubes. (4) Immediately cut off the faulty equipment. (5) Start the startup pump (steam pump) to transfer the oil from the bottom of the fractionation tower to the tank area. (6) Each return pump, air cooler, etc. shall be shut down as appropriate. (7) Where conditions permit, each position should prioritize thorough cleaning over superficial cleaning. (8) The coke tower is switched to venting mode, while the old tower is handled normally. (9) Strengthen the temperature control of the venting system and the oil rejection cooling tank. (10) Compressor and absorption stabilization cut-off system; rich gas is sent to the flare. (11) Others shall be handled as normal shutdowns. Precautions: It is strictly prohibited to allow the heating furnace tubes to overheat and cause coking; the cooling rate of the heating furnace must be controlled properly. The oil separation tank should not retain liquid at a high level for long periods, and it is strictly forbidden for any equipment to operate under excessive pressure. In emergency situations, the removal of the interlock is carried out by the operator on site, and it is sufficient to report it promptly after removal. This post was last edited by Bai Ding on 2009-4-6 18:19.]

7.2 Emergency Accident Response Plan: In the event of an accident such as a fire or explosion at the facility, and if the situation cannot be controlled immediately, the emergency shutdown plan must be implemented. The principle of emergency shutdown is applied first and foremost to ensure the safety of personnel. The emergency shutdown procedures are as follows: 1 – Report to the plant’s dispatch team and the unit’s management; if the fire gets out of control, call 119. 2 – For the heating furnace: rapidly reduce its temperature, and quickly shut down TV1006/TV1007; also reduce the furnace’s operating capacity, and close the manual valves of TV1006/TV1007. The unit should then be switched to a closed-loop operation mode. —In the event of a tube rupture, immediately follow procedure 7.3.1 – 3‑Fractionation System: rapidly increase the system pressure to 0.1 MPa to prevent tower flooding accidents. —Increase the reflux at various sections of the distillation tower, and strictly control the temperature at the top of the distillation tower to be <125°C. —Ensure a stable liquid level at the bottom of the fractionation tower. —And cut off the medium at the point of fire or explosion in conjunction with the relevant positions. 4 – Coke tower system — Works in conjunction with the shift leader to carry out the closed-loop process. —Activate the venting system promptly, use the vent valves to control the pressure at the top of the coke tower, and strictly prevent tower overpressure incidents. 5 – Pump control system: Work in coordination with other teams to quickly shut down the pumps, and cut off the fluid at the location of the fire or explosion as soon as possible. 7.3 Handling of Common Accidents 7.3.1 Emergency Plan for Process Pipeline Ruptures 1 – Report to the plant’s dispatch department and the facility’s management. – Report to the plant’s dispatch department, as well as to the facility’s management. – If a fire breaks out and is large enough to be difficult to control, call 119. 2 – Response measures – Immediately stop the transfer of materials and shut down the pumps promptly. – Cut off the flow of fluid at the location where the fire or explosion has occurred. —Cool down the system and vent it to prevent pressure buildup; if it poses a threat to safe production, proceed with an emergency shutdown. Before the fire department arrives, use fire-fighting equipment to extinguish the fire while ensuring personal safety, in order to prevent the fire from spreading. 7.3.2 Emergency plan for fires and explosions in the facility: The production process in coking facilities is highly continuous, and the process conditions involve high temperatures and pressures. The raw materials, products, as well as other hazardous materials used have properties such as flammability, explosiveness, toxicity, and corrosivity. During normal production, if a pipeline leaks, the leakage of the fluid can lead to fires, explosions, and toxic releases, causing devastating damage to the entire enterprise. 1 – Report to the plant’s dispatch team and the plant management. – In the event that the fire is large and difficult to control, call 119. 2 – Take action: Cut off the power supply; shut off the materials flow and relieve pressure as soon as possible. Rapidly cool down the heating furnace by shutting off TV1006/TV1007. Reduce the output of the heating furnace. Close the manual valves of TV1006/TV1007. Switch the unit to a closed-loop operation mode. —Before the fire department arrives, use fire-fighting equipment to extinguish the fire and prevent it from spreading, ensuring personal safety in the process. As mentioned above, for the main operator to remove the interlock, the plant must submit an application; it should be done by the instrumentation technician. In special emergency situations, the plant operator can remove it, but a written explanation must be provided afterwards