We are going to plan for introducing PFO in our delayed coking VR feed (not more that 5 MT/Hr). PFO having higher diolefine content. as i heard that it can create problem in down stream unit hydrocracker like gum formation. so kindly give your comments can we go for PFO introducing in VR feed? what actions we have to take before introducing PFO? can diolefins create problem in our heater? because previous study tells that high parafinic & napthanic feed not good as a feed for DCU but they didn't tell regarding diolefins.