When starting up a liquid-liquid extraction column, which phase is introduced first: the continuous phase or the dispersed phase?
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As the title suggests, are there any principles for starting up a liquid-liquid extraction tower? It doesn’t matter whether the continuous phase is introduced first to fill the tower; it’s possible to introduce the continuous phase first or the dispersed phase first I’ve just started learning about sulfolane extraction of aromatics and don’t understand it very well. Please ask the experts to answer.
The extraction solvent should be added first, followed by the medium to be extracted. First, the extraction solvent is a high-boiling component; it is necessary to establish a liquid level at the bottom of the tower to prevent the extraction medium from entering the outlet pipelines at the bottom of the tower. Second, ensure that the products exiting the tower top are qualified as soon as production begins.
Thank you for your advice. In our unit, the extraction tower uses a more advanced extraction solvent; oil is then added until the tower is filled (with oil acting as the continuous phase). After that, the oil pump is stopped, a solvent circulation system is established, and oil is added again. I’ve always found the standard operating procedures to be strange; from what you’ve said, I understand them a bit better now.
This post was last edited by ylb913 on 2015-10-6 at 15:55. 1. This procedure is correct; before introducing oil again, it is necessary to ensure that the extraction solvent has been circulating for a sufficient amount of time, so that the oil product about to be discharged from the top of the tower is of satisfactory quality. 2. Qualified oil should be introduced from the beginning if possible. 3. The circulation of the extraction solvent should be established earlier, in anticipation of the official feeding of the oil to be extracted.