Weekly Topic: Methods for cleaning the tubes of the overhead condenser in polymerization reactors when they become severely clogged; participants will receive 10~30 wealth points as a reward.
Thread Content
Currently, polymerization reactors with a capacity of over 105 m3 all use top condensers for heat exchange. Issues such as poor coating efficiency, insufficient flushing water volume, and the condensers being turned on too early can easily lead to self-polymer deposits clogging the tubes of the top condensers. Let’s discuss the methods for dealing with clogged tubes in the drum top condenser. First of all, let me say this as a way to spark further discussion. Our kettle top condenser tubes have experienced blockages; a large amount of rust and debris resulting from the oxidation of the coating material is removed from inside the coated nozzles each time, and this can sometimes cause the nozzles to become blocked. The cleaning method involves first using a high-pressure tank cleaning gun at 500 Bar for rinsing; if the self-polymer cannot be removed by this method, a tank cleaning gun at 1200 Bar is used for cleaning. In the most severe case, it was cleaned using a external cleaning gun capable of 2600 Bar pressure.
Blockage of the tube bundle in the overhead condenser of the polymerization reactor
We also use high-pressure water guns to clean blockages in similar heat exchangers; it’s convenient.
What is the pressure of the high-pressure gun you use for cleaning? What to do when a tube cleaning gun with severe partial blockage cannot be cleaned?
What we clean is carbon black, and the maximum pressure used is 1800 bar; it’s rare to encounter cases where cleaning isn’t possible. If the heat exchange area is sufficient, any small amount that remains uncleaned can simply be removed by reapplying the cleaning process. These days, productivity is what matters most.
The blockage is so severe that after N rounds of high-pressure flushing, could there be changes in the wall thickness of the pipe or due to other factors? If it can’t even be cleared with such flushing attempts, then what’s the point of continuing? Either give up and seal it off directly, or replace the tubes. If the equipment is severely worn out, it’s better to just buy a new one – the extra cost isn’t worth it. Of course, chemical agents for flushing aren’t recommended; a construction plan needs to be prepared first, to determine whether such methods might have adverse effects on the fluid being handled.
For this clogging issue, the first thing to consider is how to optimize the operations in order to reduce clogs. If cleaning with a water gun isn’t effective, one might try using solvents for dissolution or heating the area. I’m not aware of the composition of the materials used there; sometimes, for more stubborn cases, it’s possible to use a wrench along with a steel rod, with a drill bit welded to the top of the rod. However, improper use of this method can damage the tubes, so it’s crucial to address the problem at its source by optimizing the operations
It’s made of PVC, which cannot be melted by ordinary solvents; using fire is definitely not an option. The stainless steel tubes are prone to deformation, and it’s a Class A explosion-proof factory. I’ve seen those that use electric drills along with rebar, but it’s easy to damage the tubes.
When the congestion is really severe, there’s no other option but to outsource high-pressure cleaning. When looking for a high-pressure cleaning company, it’s best to choose one that specializes in this area, such as Shanghai Chlor-Alkali Cleaning Company. Of course, what is more important is to maintain good control in daily production, in order to prevent or delay the occurrence of self-polymerization-induced clogging as much as possible. This requires optimizing the use of the reflux condenser during the production process, as well as ensuring proper implementation of anti-sticking measures for the reactor and adequate cleaning procedures for discharging the product. It’s impossible to completely avoid blockages; delaying the likelihood of such blockages and carrying out regular cleaning are probably the best ways to protect the equipment!