Q & A > Question Details
In the our hydrotreating naphtha plant total sulfur is increased more than .5 ppm (this is my specification) and this hydrotreated naphtha (HTN) used to Aromizing unit to produce Aromatics. As you know, in the furnace of CCR platformer DMDS is used to passivate furnace tubes ,but when total sulfur increase more than .5 ppm in the feed of CCR platformer we stop injection of DMDS in the feed of CCR platformer and the question is :
can we stop the injection of DMDS in the feed of CCR platformer in case of total sulfur increase more than 0.5 ppm in HTN?
does the increase of TS in HTN can do the role of DMDS in furnace tube ?
24/03/2019 A: Virendra Kapoor, Petroleum Refining Consultants, vkkapoor9@yahoo.com
It is advisable to keep sulfur in HTN below 0.5ppm. DMDS easily decomposes to H2S and passivates the material of construction in furnace while sulfur more than 0.5 ppm of HTN would not decompose and add to CCR cat deactivation.
23/03/2019 A: Satyalal Chakravorty, Sr Consultant, satya1354@yahoo.co.in
Traces of sulfur compounds in feed are converted to H2S in the reformer and accumulate in the H2 recycle, where the H2S is readily measured. I think you go by measuring H2S content in Recycle gas. Use reliable method. Verify what licenser / catalyst vendor has said about the limit/ control level.