Shell and tube side cleaning of a severely fouled u-tube exchanger Summary
This international petrochemical company shipped a severely fouled styrene polymer bundle to Tube Tech in order to minimise costs whilst swopping over with an identical replacement. A production upset led to cured blanket of styrene polymer fusing between all the tubes forming a very hard, brittle deposit on the shell side of the exchanger.
A UK based international petrochemical company shipped a severely fouled styrene polymer bundle to Tube Tech in order to minimise costs as they own an identical changeover replacement already. A production anomaly led to a thick, hard, brittle deposit forming on the shell side of the bundle and also severe bend blockages in tubes. Our challenge was develop a method to unblock polymer from the U Bends within a small 2m square footprint in front of the exchanger so in future it could be cleaned in-situ, saving on crane costs, scaffolding, damage, gaskets, bolts and third party costs. A triple lance feeding mechanism was modified to allow lances to negotiate and unblock the every U-Tube. The client correctly pointed out that it was a pointless exercise if only the straight section was cleaned and the hairpin bend left blocked. By using Tube Tech’s globally patented Plate and Shell Jet every last particle of fused polymer was removed, even from deep inside the bundle. All the tubes were unblocked, descaled and polished using the modified triple lancing method.