Are the locations for injecting corrosion inhibitors and water at the top of the atmospheric and vacuum distillation tower the same?
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Corrosion inhibitors are injected at the air-cooling inlet of each stage of the vacuum pump used for reducing the head pressure; is water injection also carried out at this location?
If water injection is available, it should be at an adjacent location behind the corrosion inhibitor injection port.
So, compared to relative top reduction, isn’t the water injection port also not relevant? Since top reduction involves multi-stage evacuation and air cooling, corrosion inhibitors must be added at the air cooling inlet of each evacuation unit.
Previously, water was injected into our unit in front of the vacuum pump; later it was moved to the top of the tower, as it was considered better that way. We only inject corrosion inhibitors into the primary distillation tower and the atmospheric pressure tower, while the vacuum tower is fed with neutralizers and ammonia. The neutralizers are injected together with water
First of all, thank you to the friend upstairs. Excuse me, chem2008: when you reduce the pressure at the top of the tower, you only inject ammonia water and a neutralizing agent. The neutralizing agent and the water are both sent to the top of the tower; so where is the location for injecting ammonia water? In front of the extractor? Looking forward to your reply, thank you!
Pre-cooling water injection and low-temperature water injection are both located on the tower top distillate line, that is, before the air-cooling or water-cooling inlet; the order of their placement does not matter. There’s no need to fill in levels 1 and 2; even if it is done, it won’t have any effect as the vapor will blow them away due to vacuum. The key is to inject at a low rate at the start of operation, and only begin injecting water after a film forms in the pipeline. Now everyone uses mild substances as alkalis, which only serve to neutralize.
Note: Water should be added first before injecting the corrosion inhibitor; the amount to be added each time the system is started should be kept at 100 ppm to form a film, and this level should gradually be reduced to around 40 ppm as the iron ion concentration decreases
There is no need to inject water at levels 1 and 2; I agree with what was said on floor 6. However, in daily operations, although our device has a water injection process, it is hardly used. Ammonia water is injected at the vaporization line at the top of the tower.