Synthetic coal contact, during normal production, it was found that the bed temperature dropped rapidly downwards, but no major abnormalities were found in other process parameters!
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Synthetic coal contact, during normal production, it was found that the bed temperature dropped rapidly downwards, but no major abnormalities were found in other process parameters! There are mainly those reasons! ! ! This post was last edited by snowdfr on 2009-3-19 20:39 ]
One is liquid； Second, the cold shock valve is opened too wide;
It is possible that the ammonia level is false and contains liquid ammonia. When liquid ammonia is added, the temperature at the inlet of the synthesis tower does not drop significantly, and the temperature of the synthesis tower drops rapidly. If the cold shock (cold sub-line) fails to open, the flow rate of the cold shock (cold sub-line) will change significantly. This post was last edited by FEIJING on 2009-3-20 09:20 ]
Personally I think there are the following reasons: 1. The liquid level in the ammonia separator or cold exchanger is false, causing the synthesis tower to carry liquid. ； 2. The gas composition is not good. If the trace amount is high, the toxic and harmful components to the catalyst will increase. ； 3. If the circulation volume suddenly increases, you can check the short circuit of the system and the circulating machine, and whether there is any change in the on-site valve position. ； 4. The content of inert gas increases.
Add something: Chronic poisoning by trace amounts of carbon monoxide and hydrogen sulfide in the gas cannot be ignored. ； Especially in the case of large load, load production should be established and the load should be added after the syngas reaches the target.
Other reasons can also be considered, 1. The premature aging of the catalyst should also be considered. 2. The cold air pipeline is short-circuited. This situation is rare. 3. The catalyst layer is unevenly filled, which is rare.
It looks like it contains ammonia. If there is a problem with its temperament, it should respond to pressure and the temperature line should be dispersed.
If there are no obvious changes in other process parameters, it can only be that the instrument is broken.
If it can be determined that the ammonia cooling temperature, hydrogen-to-nitrogen ratio, inert gas content, supplementary gas volume, circulation volume, cold side line and other process parameters have not changed. When the bed temperature drops, you should also pay attention to: 1. Waste pot liquid level. Too high a liquid level will cause the entering tower temperature to drop. 2. Ammonia content and cold cross liquid level prevent liquid ammonia from being brought into the synthesis tower. 3. Trace amounts of supplementary gas. Prevent toxic gases from entering. 4. Copper liquid enters the loop. Open the supplementary gas oil-water separator drain valve to check. 5. The short-circuit valve of the compressor prevents gas from taking a short-cut and entering the synthesis loop directly without refining.
1. Belt liquid (copper washing liquid, cold cross ammonia stripping liquid, oil and water)； 2. The cold shock valve is opened too wide; 3. The trace amount in the fresh gas exceeds the standard. ； 4. The amount of fresh air suddenly decreases ； 5. A sudden increase in the amount of inert gas ；
Bed temperature drops rapidly: 1. Check whether liquid is brought into the synthesis tower. 2. Is the cold shock valve normal? (I encountered this once. The opening of the cold shock valve did not change, but it was fully opened. Later, after the car was stopped, the valve was fine again.) 3. Whether the front gas component exceeded the standard in a trace amount.
If the temperature drops rapidly and overall, it is mainly due to liquid inclusion.
“"Other process parameters are normal", the possibility of catalyst poisoning is greatest.
“"Other process parameters are normal", the possibility of catalyst poisoning is greatest. I don’t agree with it. This has happened many times in our old synthesis. This is usually caused by liquid inclusion. Synthesis operations generally know that liquid is included without thinking about it. The ammonia is separated into a false liquid, and the pressure rises rapidly.
The possible reasons are as follows (from most likely to least likely): 1. Bring liquid into the synthesis tower ； 2. High trace amount, catalyst poisoning ； 3. Operation errors, excessive circulation volume, or excessive opening of the cold shock valve.