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I am working in Hydrogen generation unit. I want to know whether if naphtha preheater tubes got a leak and super heated HP steam went to naphtha side then would superheated HP steam go to hydrogenerator (Co-Mo catalyst)? What is the effect of steam on Co-Mo catalyst life?
 
Answers
11/08/2014 A: Ganesh Maturu, Self, maturu.ganesh@gmail.com
Steam in Naphtha feed reduces the H2 partial pressure at the reactor inlet and outlet. This may reduce the hydrotreating and hence catalyst doesnt work efficiently. Catalyst severity needs to be increased to compensate H2 partial pressure and hence catalyst life reduces because of this problem. Hence steam in naphtha feed indirectly harms the catalyst and hence care should be taken.
03/08/2014 A: Virendra Kapoor, Petroleum Refining Consultants, vkkapoor9@yahoo.com
Co-Mo Hydrotreater catalysts are regenerated by regulated amount of air in presence of sufficiently high flow rate of steam. So it is obvious that these catalysts are resistant to steam. One has to be careful that steam should not cot condense over the catalyst. Water in liquid phase has adverse effect on mechanical strength of catalyst.
24/07/2014 A: keith bowers, B and B Consulting, kebowers47@gmail.com
There is some literature about hydro-thermal damage (surface area loss) to some silica-alumina catalyst support. It happens during regeneration , burning coke off, and not ENOUGH steam or nitrogen dilution to keep the flame front temperatures down enough. If is real difficult to determine the burning zone temperatures though. We 'burned' from bottom up and pulled the center vertical thermocouple up as the burning zone advanced. The peak temperature can be surprisingly high for a short period with a short burn zone if there is too much oxygen on the first pass.
24/07/2014 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
Depending on the size of the hole, I would expect the water vapor to be too diluted to affect the operation or integrity of the catalyst itself.