Butane stripping column operation

The top temperature is primarily influenced by the composition; if heavier components reach the top of the tower, the temperature will remain high even at low pressures.

At present, the cooling efficiency of the air coolers and water coolers is poor; when the top temperature is low, the pressure at the top of the tower is high, and when the top temperature is high, the pressure at the top of the tower decreases. Our butane removal tower separates liquefied gas from the top and light naphtha from the bottom

If the cooling load is insufficient, the light components cannot be completely condensed, which leads to an elevated tower pressure. In such cases, the light components may flow towards the bottom of the tower, resulting in a lower temperature. However, when the temperature rises, the tower pressure actually decreases; this is not easy to understand. For the first scenario, it is possible to reduce the load or vent some gas to see what happens

That’s the case; such a situation occurs during operation – when the top temperature is high, the pressure drops. By introducing backflow to lower the temperature, the pressure rises. The non-condensable gases in C1C2 play a role here. Is the content of C1C2 components high in the liquefied gas? Is there an deethanizer ahead? If not, there will be some gas leakage; your cooler won’t cool down properly. Have you checked the equipment? The water temperature, water pressure, and scaling in the water cooler, as well as the fans and heat sinks in the air-cooling system, all need to be checked. Does the temperature at the top of the tower become too high and fail to drop? If the product flow is high and the quality is satisfactory, and the cooling equipment is working properly yet the temperature still doesn’t drop, it’s possible that the load on your facility has reached its limit; in such cases, it may be necessary to reduce the flow rate. As mentioned earlier, the relationship between tower top temperature and pressure is influenced by the C1 and C2 components in the liquefied gas. When the reflux is sent back, it gets vaporized again, and these non-condensable C1 and C2 gases cause high pressure. With high pressure, fewer light components rise to the top, so they settle downward. If the temperature at the bottom of the tower isn’t increased over time, the naphtha components will become lighter; conversely, the liquefied gas components will become heavier. It’s necessary to monitor this situation continuously, as weather conditions can also have an impact. These are just my personal opinions and insights; please feel free to correct me if I’m wrong