Regarding operational stability of the debutanizer tower

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Our new plant has an atmospheric tower and a debutanizer tower. I have just finished asking about the atmospheric pressure tower, and now I would like to ask you about the debutanizer tower. Most of the distillate at the top of the primary distillation column is naphtha, but it still contains part of butane and propane. Therefore, after passing through the heat exchanger, it enters the debutanizer to obtain stable naphtha. The height of the debutanizer tower is about 50 meters. The overhead distillate, which mainly consists of butane and light naphtha, exchanges heat with the heat entering the debutanizer tower, is air-cooled (height is 35 meters), and then enters the reflux tank, the height is about 15 meters. The designed operating pressure of the debutanizer tower is 9.5 kg, and the actual operating pressure is 9.5 kg. The designed operating pressure of the reflux tank is 9 kg, and the actual operating pressure is 9.7 kg. In addition to the problem with the normal pressure tower I asked just now, another problem with this butane towing tower is that the liquid level in the reflux tank fluctuates greatly. The reason is that the pressure ratio of the reflux tank is relatively large, and the medium after air cooling is a two-phase flow. The two-phase flow forms a slug flow under the influence of the pressure of the reflux tank, which ultimately leads to the medium entering the reflux tank being pure fluid for a while and pure gas for a while. ask: How do you overcome this problem in your actual devices? Thanks!