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We are trying to determine the appropriate lab test and normal analytical ranges in order to bring imported MVGO to our new hydrocracking unit. Licensor is concerned is about presence of Na and Cl but also other contaminants such as P. What are the normal ranges of Na, Cl and other metals to bring to the hydrocracking unit to avoid catalyst damage?
 
Answers
14/06/2015 A: Sarath Konda, DuPont India, sharathsatya@gmail.com
Na is higly detrimental to Hydrocracking catalyst as low as 0.3ppm can reduce the catalyst activity by 50%. Graded/ de-metallization bed of the reactor is purely based on the pick-up of metals on its surface, processsing higher metal content will reduce the graded bed life. Metals breakthrough from graded bed will impact the active catalyst and reduce the catalyst activity drastically.
Apart from increase in metal content will increase the pressure drop in th top bed of the reactor. CL in feed will also NH4CL salts deposition downstream of the reactor. If no wash water provision is there for flushing of NH4CL salts it can plug exchanger, also possibility of under deposit corrosion due to CL- SCC cracking in higher.
It is highly recommended to analyze metals in your feed accurately and refer to your licensor for appropriate guidance on processing of MVGO
27/02/2015 A: Sridhar Balakrishnan, Bharat Oman Refineries Limited , laksrid@yahoo.com
Metals , sodium content in the hydrocracking unit feed should be in the range approx. less than one ppm. Chloride content should also in the same level. It also depends on the crude oil source.
Chloride can be determined by Microcoulometry; metals and sodium content by Plasma Spectroscopy .