Patent EP-2468838-A1 (EP)
Inventor: DUPASSIEUX NATHALIE
IPC: B01J8/04
Filed: 2011-11-17
Abstract: The process for hydrotreatment of feedstock from renewable sources for production of paraffinic hydrocarbons in the presence of 50% of excess hydrogen of theoretical hydrogen consumption and by hydrotreatment conditions in a fixed bed reactor having 3-6 catalytic zones arranged in series and comprising a hydrotreating catalyst, comprises dividing the flow (F) of the total feedstock into a number of different partial flows (F1 to Fn) equal to the number (n) of catalytic zones in the reactor to produce an effluent containing paraffinic hydrocarbons. The process for hydrotreatment of feedstock from renewable sources for production of paraffinic hydrocarbons in the presence of 50% of excess hydrogen of theoretical hydrogen consumption and by hydrotreatment conditions in a fixed bed reactor having 3-6 catalytic zones arranged in series and comprising a hydrotreating catalyst, comprises dividing the flow (F) of the total feedstock into a number of different partial flows (F1 to Fn) equal to the number (n) of catalytic zones in the reactor to produce an effluent containing paraffinic hydrocarbons, where a first partial flow (F1) is injected in a first catalytic zone (Z1), the second partial flow (F2) is injected in a second catalytic zone (Z2) and then if n is greater than 2, the different partial flows are injected in the successive catalytic zones in increasing proportions such that F1/F is less than or equal to F2/F or is less than or equal to F3/F until F(n-1)/F is less than or equal to Fn/F, subjecting the effluent to a separation step for separating a gas fraction containing hydrogen, carbon monoxide, carbon dioxide, hydrogen sulfide, water and light gas and liquid fraction containing paraffinic hydrocarbon, recycling a part of the liquid fraction containing paraffinic hydrocarbon to the first catalytic zone so that a weight ratio between the recycle flow into the first catalytic zone and the partial flow (F1) introduced into the first catalytic zone is greater than 10. A weight ratio between the recycle flow into the first catalytic zone and total flow of feedstock is less than 0.5. The hydrotreatment step is operated at a temperature of 200-400[deg] C, a pressure of 2-15 MPa and a speed velocity of 0.1-5 h -> 1>and in a presence of total quantity of hydrogen mixed with feedstock such that a ratio of hydrogen or feedstock is 300-1500 Nm 3>hydrogen/m 3>of feedstock. The separation step is carried out by a high temperature high pressure separator operating without reduction of pressure at a temperature of 145-280[deg] C. The different partial flows are same or different. The feedstocks are co-treated with: a petroleum distillate type consisting of gas oils; kerosene atmospheric direct distillation of gas oil; and/or kerosene from conversion processes. The part of the liquid fraction containing paraffinic hydrocarbon undergoes hydroisomerization step in the presence of a hydroisomerization catalyst. The hydroisomerization step is operated at a temperature of 150-500[deg] C, a pressure of 1-10 MPa, a speed velocity of 0.1-10 h -> 1>and flow rate of hydrogen such that a ratio of hydrogen/hydrocarbon volume is 70-1000 Nm 3>/m 3>of feedstock. The hydroisomerization catalyst comprises a metal of group VIII and/or a metal of group VI B as a hydrogenating function and a molecular sieve or an amorphous mineral support as a hydroisomerization function. The effluent from the hydroisomerization step is subjected to a separation step to obtain a gaseous including a gasoline cut (150[deg] C-) and a distillate cut (150[deg] C+) containing kerosene and/or diesel.