The Nalco Water program for pygas units includes:

POLYMER INHIBITORS AND ANTIFOULANTS FOR THE DISTILLATION TRAIN
These products are designed specifically to withstand the high temperature environment typically encountered in this area.

"CRUST BUSTER" TECHNOLOGY FOR HYDROGENATION REACTOR FOULING CONTROL
Special dispersant technology reduces reactor bed fouling while causing no harm to the catalyst.
 
CORROSION INHIBITORS
A neutralizing amine, a filmer or a combination of the two can be employed to minimize corrosion in the pygas unit. The best practice product is selected after a detailed system survey by Nalco Water to ensure the most cost effective performance.