Low temperature methanol wash back to temperature
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What does low-temperature methanol wash back to temperature mean? What should be done?
Low-temperature methanol rewarming refers to rewarming the low-temperature system after removing the process gas. Close the liquid phase valve of the ammonia cooler so that the liquid ammonia in the ammonia cooler completely flashes away and there is no liquid ammonia. Methanol continues to be recycled. The cycle can be stopped after the temperature returns to above zero.
When was low-armor rewarming used? I haven't heard of rewarming here. Are you preparing for a big stop? still?
When the cold zone equipment needs to be overhauled, if the low-temperature methanol washing system needs to be heated up due to maintenance or other reasons, the methanol circulation can be maintained with the refrigeration unit shut down until the system warms up. In order to speed up the heating of the system, it is recommended to continuously add steam to the C4 tower reboiler. At the same time, the alcohol-water separation tower C5 continues to operate to reduce the water content in methanol as much as possible.
I used to think that the temperature returned after the breath was cut off. Methanol temperature increases. To control it from rising too high. . hehe. Newbie. . Wrong understanding
It should be methanol regeneration. At this time, open the vent valve. Increase the amount of regeneration steam in the hot generating tower. At this time, wait until the temperature of each point in the system rises to 0 degrees Celsius, and take a sample from the outlet of the pump at the bottom of the stripping tower to analyze that the hydrogen sulfide is less than 5 mg/m3.
What is the criterion for the end of warming? Can I take fluids immediately after that? When the circulation cannot be maintained, stop the circulation and use diversion to drain the liquid. Then what is the reason why the circulation cannot be maintained? What are the respective liquid levels?
What is said above all makes sense, isn’t it just to return to above 0 degrees?
parking* * The steps are like this. Load reduction -> Cut gas and maintain pressure -> Methanol regeneration -> Methanol rewarming -> Stop circulation and withdraw liquid -> Drain the methanol -> Add water to circulate and rinse -> Drain, dry, and maintain slight positive pressure. The end of rewarming is usually that the methanol outlet temperature at the bottom of the hydrogen sulfide concentration tower is 10°C. If the rewarming temperature is too high, it will easily cause the cold insulation material to melt.……
After confirming the shutdown for overhaul, continue to maintain the cycle after cutting off the gas, close the ammonia inlet valves of each ammonia cooler, increase the steam volume of the regeneration tower, and continue to operate the water system until the liquid ammonia in each ammonia cooler evaporates and the temperature of the cold zone gradually rises above 0 degrees to facilitate maintenance, and the drainage replacement is handed over for maintenance.