Service life of the vinyl chloride high-boiling tower
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The service life of our current high tower reboilers is particularly short; they turn black when the bottom of the tower is emptied. It’s like melted plastic – it’s especially difficult to clean. We can’t figure out the reason for this. I wonder if other professionals face the same issue; do you have any good suggestions?
It is possible to consider adding antipolymers and dispersants to the feed or in the reboiler; companies such as GE, Nalco, and Buckman offer chemicals for use in such processes, which can extend the period between coking events in the reboiler. In addition, adjustments to the reactor temperature, increases in emission levels, and the control of the content of components in the feed that are prone to polymerization and coking also need to be taken into consideration
The last edit to this post was made by wang*neng on 2014-1-2 at 10:57. A polymerization inhibitor should be added to the reactor bottom, and the moisture content of the material fed into the reactor must also be controlled (water is one of the main factors that cause polymerization), as well as the temperature at the reactor bottom. (It is best to use a circulation with a large temperature difference.) The tray plates should also preferably be anti-clogging sieve trays, and an anti-adhesion coating should be applied to them after each cleaning.
The reboiler in the high-boiling tower must have its carbon deposits removed during annual shutdown repairs; these deposits are removed using drills, but this can also cause tube cracking and equipment leakage, primarily due to the carbonization and coking of dichloroethane! I haven’t tried using an anti-sticking agent for the pot. Reducing the time interval between emissions of high-boiling substances and controlling temperature are effective solutions.
That’s because you steamed the residue too intensely.
The reboiler in the high-boiling-point tower is generally cleaned once a year, and the following aspects need to be carefully controlled: 1. Control the temperature at the bottom of the high-boiling-point tower; it should not be too high. 2. Regularly discharge the high-boiling substances to prevent their accumulation and subsequent coking due to heating. 3. Use of a polymerization inhibitor to maintain a stable addition rate during the polymerization reaction time.
Under normal circumstances, discharge should be carried out regularly, usually at least once a day.