Investigation malfunctions demister of BT-1821 column using nuclear technique

BT-1821 is the process column to produce purified terephthalic acid. The unit process with a diameter 2.8m and high 24m is suspected malfunctioning based delta pressure at the top and bottom of the column. The nuclear technique has been performed to diagnose this problem by using a Co-60 source, scintillation detector, a mechanical device support, and safety equipment. Results of the investigation had identified a malfunction on the demister blockage which inhibit gas flow and increased in delta working pressure. The unit also works according to specifications on the conditions on the mechanical drawing. Level of liquid identified according to the recommendations. Those are not observed collapse tray or flooding inside the unit. This report can be reference to repair on maintenance schedule efficient and effectively. (author)