Ethylene Plant Quench Tower Packing Removal

[joliemarcose]

Hi, Few year back when we tried to remove ethylene plant quench water tower random packing, we found packing are sticked together due to TAR/coke and become lumps, we were not able to remove packing from tower. After restart of plant we see there is channeling and higher temperature at outlet of tower. Now again we want to try removal and replacement of packing. Anyone has experience of packing removal? What is the successful method of packing removal? How can we loosen the packing from lumps what we see earlier few year back? Any one has experience of any chemical company which can do this job within short time, please share name. Last time we tried to use vacuum method of removing packing but was not successful.
Also if any one have experience of successful decontamination of the tower before opening, please share information.

[a.aryan]

Random packings (whatever type) present horizontal surfaces that hold-up liquid i.e. increase the liquid residence time. They should not be used in services where there is a risk of coking. It is much better to use grid packing or trays suitabel for sever fouling (sheds, angle iron, baffle etc.) in this service.