hydrotreating process of renewable materials with improved gas recycling

摘要

The invention relates to a process for hydrotreating a feed from renewable sources in which the total feed stream f is divided into numerous different parts of feed stream f1 to fn equal to the number of catalytic zones n, in where n is an integer in the range 1 to 10, with the hydrogen mass flow rate sent to the first catalytic zone representing more than 80% by weight of the total hydrogen mass flow rate used in the process. hydrotreating to produce at least one effluent containing paraffinic hydrocarbons from the reactor outlet, said effluent obtained from step a) undergo at least one separation step, with at least a portion of the said liquid fraction contains paraffinic hydrocarbons recycled in the first catalytic zone and subsequent catalytic zones in such a way that the local recycling ratio for each m of the beds, that is, the weight ratio between the stream of said liquid recycle fraction and the portion of the feed stream introduced into the catalytic zone fn is 2 or less and local dilution ratio in each of the beds, i.e. the weight ratio between the amount of liquid and gaseous streams introduced into the catalytic zone and the part of the feed stream introduced into the catalytic zone fn is less than 4.