Online disassembly procedure for auxiliary boiler burners – Emergency response plan

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This post was last edited by Small and on 2017-8-26 23:44. It is an emergency response plan for the online disassembly of auxiliary boiler burners, developed by my teachers at the methanol plant. I. Reason for handling: The burners in the methanol workshop are of the type that use turbofan-driven, self-priming air supply systems; originally, these burners were designed to use untreated, room-temperature fuel gas. However, now they use fuel gas heated to around 170°C, which causes the rotating components of the burners to overheat and lose lubrication, leading to damage. As a result, after the auxiliary boilers operate under high load, several of their burners stop functioning – or, after some time of use, individual burners cease to work. To ensure safe, stable, efficient, and energy-saving production, the workshop recommends carrying out online repairs on these burners as soon as possible, taking advantage of the current low load levels, in order to eliminate the potential hazards posed by this issue. II. Risk Analysis: 1. Explosion caused by burner flameout and backfire in the auxiliary boiler furnace ； 2. Significant fluctuations in furnace negative pressure caused the converter burners to go out ； 3. Incidents of burns caused by spraying flames or high temperatures occur during online disassembly processes: III. Preventive measures: 1. Explosions can result from reignition after the burner in the auxiliary boiler chamber goes out ； 1.1 An appropriate time should be chosen for the online disassembly process; it is best to carry it out when the load on the auxiliary boiler is at its lowest. It is ideal to have 2–3 burners operating in the auxiliary boiler. During the disassembly process, process and mechanical specialists must work together carefully, meticulously, and in close coordination. Once it is detected that a burner has stopped functioning, the mechanical team should immediately halt operations, while the process team should promptly cut off the fuel supply to that burner. Only after coordinating with the control room staff to reignite the burner and restore the process parameters can work resume. 1.2 The supervisors should pay attention to monitoring TI-1247, TI-12136, and TI-1220 to prevent backfire. 2. Significant fluctuations in furnace negative pressure caused the converter burners to go out ； 2.1 Throughout the online disassembly process of the burners, the on-duty team should organize personnel appropriately, assign dedicated personnel to monitor the combustion status of the auxiliary burners and roof burners at the site, and designate a main controller to oversee the furnace area and assist with the online disassembly process. 2.2 Mechanical specialists shall prepare special baffles in advance; the ventilation volume through the openings in these baffles should be similar to the normal air intake volume of the burners, in order to minimize fluctuations. The control personnel shall adjust the operating conditions of the exhaust fans and blowers promptly based on the fluctuations in the negative pressure inside the furnace. 3. Incidents of burns from spray fire or high-temperature scalds during online disassembly: 3.1 Safety must be prioritized throughout the online disassembly process of the burner; personnel involved must wear safety helmets and heat-resistant gloves, and professional safety supervisors must be present, along with emergency response measures in place. 3.2 When lifting the burner, it must be secured firmly; during the lifting and lowering of the heavy object, the maintenance personnel should move slowly and be careful to avoid collisions with other equipment or interlocks. IV. Technical requirements and safety precautions for online disassembly: 1. The timing of the disassembly process should be carefully chosen, with the flue gas temperature at the auxiliary boiler outlet TI-1247 being between 380–400°C, the negative pressure in the auxiliary boiler furnace being around -200 Pa, and it is advisable to use 2 burners in the auxiliary boiler. 2. The technicians should adjust the position of the burner to be used in advance, depending on the location of the burner that needs to be removed; they should cool down the burner that needs to be removed ahead of time, and ensure that the burner currently in use is placed away from it, in order to prevent burns caused by sparks or high temperatures during the removal process. 3. The quality of the dedicated baffle is very important; the ventilation volume through the openings in the baffle should be similar to the normal air intake volume of the burner, in order to ensure minimal fluctuations. 4. Mechanical technicians should work closely with process engineers; as soon as the removed burner is taken out, a special baffle should be installed immediately, and the process engineers should adjust the speed of the exhaust fans and blowers as well as the setting of PICA-1216 in accordance with fluctuations in the negative pressure inside the furnace. 5. During the disassembly process, the technicians should remove the valve handles for the burner fuel gas on the same auxiliary boiler platform to prevent accidental opening or closing of the burner fuel gas due to collisions, which could lead to accidents. 6. Process technicians should prepare accident plans and take necessary precautions. The shift team should organize its members properly; in the event that an accident escalates, such as a large-scale flameout at the top of the converter or a backfire explosion, immediate and decisive action must be taken to prevent further expansion of the accident. 7. Online removal of nozzles cannot be carried out simultaneously; one nozzle is processed per day, and the processing of the next nozzle is undertaken only after the process has been stabilized. 8. During the entire online disassembly process of the burner, professional safety supervisors should be present to provide guidance, along with the necessary fire extinguishing tools and equipment. Methanol Workshop 2008-4-24