FISCHER-TROPSCH SYNTHESIS METHOD WITH IMPROVED CONTROL

摘要

The inventive method for producing liquid hydrocarbons by Fischer-Tropsch involves a stage (a) for generating a syngas, a stage (b) for carrying out a Fischer-Tropsch synthesis, a stage (c) for condensing a gas flow obtained at the stage (b), a stage (d) for separating the flow condensed at the stage (c), thereby obtaining a gas flow enriched in hydrocarbons and hydrogen and a stage (e) for recycling at least a part of the enriched gas flow obtained at the stage (d) towards the Fischer-Tropsch synthesis stage (b). Said method is characterised in that it consists 1) in determining two molar ratios A1 and A2 between hydrogen and carbon monoxide (H2/CO), wherein A1 is the value of said ratio in the supply of the synthesis stage (b) and A2 is the value of said ration in any of different gas flows obtained at the stages from (b) to (e), 2) in comparing the A1 and A2 ratios and 3) in adjusting the hydrogen and/or carbon monoxide concentration in the syngas in such a way that a substentially constant deviation between two A1 and A2 ratios is maintained.