Methanol Weekly Topic: What to do if the DCS crashes suddenly during methanol operation? 2016.01.17---01.23
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Methanol Weekly Topic: What to do if the DCS shuts down suddenly during methanol operation? 2016.01.17---01.23 Scoring Table: Question Name – DCS Shutdown Handling. Sequence Number, Assessment Items, Assessment Content and Requirements (Scoring Elements), Allocation Points, Scoring Criteria, Detection Results, Deductions, Scores, Remarks. 1. Preparation Work: (1) Wear appropriate personal protective equipment. 2: 2 points deducted if PPE is not worn properly. (2) Prepare walkie-talkies. 2 points deducted if they are not prepared. 2. Contacting the Control Room and Instrumentation Team: Contact the control room and instrumentation team promptly to restore normal operation of the DCS as soon as possible. 8 points deducted for each delay in making such contact. 3. Using On-Site Instruments to Maintain Production in a Short Time: (1) During the period when dealing with the instrumentation issues, all processes must enhance coordination on site. 15 points deducted if coordination among various positions is poor. (2) In the distillation process, redirect the output to the crude methanol storage tank. 15 points deducted if this adjustment is not made in a timely manner. (3) In the conversion process, check on-site parameters such as raw gas pressure, furnace negative pressure, burner backpressure, drum liquid level, and drum pressure. During the compression process, pay attention to the pressure at the inlet and outlet of the compressor; during the synthesis process, check the liquid level and pressure in the drum, as well as the pressure in the synthesis circuit. Also monitor the liquid level and pressure in the separator and flash tank to prevent high pressure from leaking into the low-pressure system. During the distillation process, it is necessary to check the temperature, pressure, and liquid level of each tower as well as the operation status of pumps and motors. 4 Points will be deducted for each missing inspection of key areas. 4 Restoration of normal production: Once the DCS returns to normal, various process parameters should be adjusted promptly. 8 No points will be given if production cannot be resumed quickly after the DCS becomes operational. 5 Safety, proper production, and other aspects: (1) Strictly follow operating procedures – 1 point will be deducted for each violation. (2) Strictly abide by management regulations – 1 point will be deducted for each violation. (3) Complete tasks within the specified time limit; 5 points will be deducted from the total score for each minute of delay, and operations will cease if the delay exceeds 5 minutes. Total: 100
Is there only one? That can’t be right. Even when it’s frozen, control is still available; one can operate and monitor from a backup machine or an engineer station. If it freezes, restart it immediately or seek help from the responsible party
DCS is a distributed control system; if the computer used for monitoring freezes, it does not affect the operation of individual control systems. Try restarting the computer used for monitoring; if that doesn’t work, seek professional assistance for repairs.
1. In a DCS, the monitoring computers and the DCS main control cards are generally redundant. If the computer freezes, the main control card is not affected; simply restart the computer. 2. If both main control cards fail, the output values usually change. If the problem cannot be resolved, the plant can be stopped manually following the standard procedures
Typically, a DCS has more than one operator station; if a computer crashes, it can be restarted.
If the console freezes, check other computers; if they also freeze and show no display, then it’s a problem with the cabinet – the situation is quite serious!
DCS control generally isn’t handled by just one computer; if one of those computers crashes, the others can be used to restart it. If that doesn’t work, a backup computer must be used
Just switch to the backup control station right away; there is usually one available. If the entire system freezes. . . I haven’t seen one in 10 years; if I really do encounter one, I’ll stop the vehicle immediately. It can be handled by treating it as an instrument air interruption; at that point, the control valves FO, FC, and FL should come into action. In addition, methods such as checking the local gauges on site and operating the control valves to shut off the bypasses around the machine should be employed, with a safe shutdown being the priority.
I’m learning about it; I’m currently looking for information on this topic