How can we ensure good stripping efficiency?
Thread Content
Recently, the liquid discharged from the stripping tower has been overheated, and the circulation load is also high. How can this problem be solved? . . . . .
If the liquid temperature in the stripper rises after operation for a while, it may be due to a malfunction in the liquid distributor of the stripper; the plant should be shut down for inspection. It mainly depends on whether the distribution holes of the stripping tube are blocked and whether there is leakage in the distribution tube. Whether there is blockage in the tube structure, etc. The system must maintain an appropriate ammonia-to-carbon ratio as well as a water-to-carbon ratio, to ensure that the components in the high-pressure system remain within specified ranges. The pressure in the high-pressure steam saturator also needs to be kept within designated limits, and the liquid level in the stripping tower must be properly controlled. If there are no problems with these, the only option is to stop the vehicle for maintenance.
This post was last edited by ttlkk on 2009-7-3 15:35. The excessively high liquid outlet temperature in the stripping tower during production is mainly caused by factors such as the tower being filled with liquid, an excessively low gas/liquid ratio, a too-high water-to-carbon ratio in the synthesis system, too high pressure in the medium-pressure steam saturator, blockages in the distributor located at the top of the stripping tower, overly high liquid level control in the tower, too low production load, and an excessively high temperature of the carbon dioxide gas fed into the stripping tower. Additionally, if the outlet liquid control valve of the stripping tower fails, and there is severe gas leakage from the stripping tower into the downstream system, the temperature of the liquid exiting the stripping tower can also rise above the normal level. If the reason for the excessively high outlet temperature of the stripping tower is an excessive amount of liquid in the tower, it can be addressed using the following methods: (1) Before feeding material, drain the liquid from the stripping tower; check again for any remaining liquid before discharging the product, and if liquid is present, it must be drained first. ⑵When driving after a short-term parking period, if the stripping tower is filled with liquid, carbon dioxide can be introduced first to empty the liquid level, followed by the addition of ammonia. ⑶After the discharge from the synthesis tower, the outlet valve of the synthesis tower should be adjusted slowly, and the pressure of the saturated steam in the medium-pressure steam saturator on the shell side of the stripping tower should be adjusted promptly. If the water-to-carbon ratio in the system is high, it is possible to reduce the speed of the ammonium methoxide pump and discharge some of the ammonium methoxide from the liquid level tank of the low-pressure ammonium methoxide condenser to maintain the level, thereby controlling the amount of water that enters the synthesis system. When the gas/liquid ratio in the stripping tower is low, it is necessary to check for leaks in the compressor sections or whether excessive carbon dioxide gas is entering the circulation system due to a malfunction of the liquid outlet control valve of the stripping tower. Furthermore, a sudden decrease in the amount of carbon dioxide coming from the boundary zone can also result in a low gas/liquid ratio. Therefore, when the gas/liquid ratio decreases, it is necessary to analyze the cause promptly and take appropriate measures.
Reply to 3# ttlkk: Can the impact of the carbon-to-water ratio on the stripping efficiency be analyzed from the perspective of phase diagrams?
Reply to 4# Achuan: The distillation efficiency is calculated based on the components, so it can be analyzed using phase diagrams.
This post was last edited by Xieshui on 2010-7-24 at 18:32. The friend above provided a very accurate analysis; it is possible that the stripping tower is blocked by debris, but it is also necessary to check the quality of the steam to see if it contains any non-condensable gases. What is the current efficiency of stripping? Has a back-purging stripping tower been used? Sometimes that can also be effective.