Pressure drop in the distillation tower
Thread Content
This unit features a distillation tower for the pretreatment of feedstock. The pressure at the top of the tower is normally 0.34 MPa, while the pressure in the reflux tank at the top is set at 0.35 MPa. The top of the tower is cooled by air cooling, and heat is supplied to the bottom of the tower through a reboiler. In the absence of any operational activities, the pressure at the top of the tower gradually drops to 0.325 MPa, which causes the pressure in the reflux tank to also drop suddenly to 0.325 MPa. The temperature at the top of the tower drops rapidly as well. Afterwards, the pressure in the reflux tank rises again, and the pressure at the top of the tower gradually returns to its normal level. What could be the reason for this? Has anyone encountered this issue before?
Does it occur frequently or just once?
I don’t know; it’s just not clear to me. I’m here to ask everyone for advice
It’s hard to say exactly what one is willing to do just by looking at the description.
A tower pressure of 0.34 MPa is achieved through pressurized distillation using the vapor phase of the material; the pressure comes from this vapor phase itself, with no additional pressure supply. 1. Check whether the reboiler steam is stable and whether the vapor-phase evaporation rate is stable ； 2. Is pressure control achieved through venting to maintain 0.34? Is there a problem with the venting control circuit, such as an overly high setting that causes the pressure to drop as soon as the valve is opened? ； 3. What is the reflux method, and is the reflux volume stable? ； The backflow suddenly increases, gas-phase condensation becomes excessive, pressure drops sharply, the air-cooling load drops suddenly, and the temperature definitely falls