An integrated process for the production of liquid hydrocarbons from a feed containing at least one fraction of biomass and optionally at least one fraction of another feed, said process comprising at least the following steps: a) a step for pre-treatment of the biomass fraction and optionally of the other fraction or fractions, comprising at least one of the operations a1), a2), a4): • a1) drying, • a2) torrefaction, • a4) grinding, b) an optional step for combining the pre-treated biomass fraction and the other fraction or fractions of the feed, which may or may not have been pre-treated, c) a step for gasification of the effluent obtained from step b) and/or of the pre-treated fraction obtained from step a) and optionally of at least one fraction of another feed introduced directly into the gasification step in an entrained flow reactor, d) a step for conditioning synthesis gas obtained from step c), comprising: • a step d1) for scrubbing with water and for fractionating said synthesis gas into at least two effluents: a first portion and a complementary portion, • a step d2) for eliminating halogenated compounds by passing said first portion through at least one suitable guard bed, • a water gas shift step d3) carried out on the effluent obtained from step d2), • a step d4) for catalytic hydrolysis of the COS and HCN compounds contained in said complementary portion of the effluent obtained from step d1) into H 2 S and NH 3, e) a step for recombination of at least one fraction of each of the effluents obtained from steps d3) and d4), f) a step for scrubbing the recombined effluent obtained from step e) with water in order to eliminate impurities such as NH 3 and HCl, g) a step for elimination of the acid gases CO 2 and H 2 S contained in the effluent from step f) with one or more chemical or physical solvents, used alone or as a mixture, h) a step for final purification over at least one guard bed in order to adsorb traces of impurities remaining in the synthesis gas obtained from step g), such as H 2 S, COS, HCN and NH 3, i) a catalytic Fischer-Tropsch synthesis reaction step carried out on the effluent obtained from step h). a) a step for pre-treatment of the biomass fraction and optionally of the other fraction or fractions, comprising at least one of the operations a1), a2), a4): • a1) drying, • a2) torrefaction, • a4) grinding, • a1) drying, • a2) torrefaction, • a4) grinding, b) an optional step for combining the pre-treated biomass fraction and the other fraction or fractions of the feed, which may or may not have been pre-treated, c) a step for gasification of the effluent obtained from step b) and/or of the pre-treated fraction obtained from step a) and optionally of at least one fraction of another feed introduced directly into the gasification step in an entrained flow reactor, d) a step for conditioning synthesis gas obtained from step c), comprising: • a step d1) for scrubbing with water and for fractionating said synthesis gas into at least two effluents: a first portion and a complementary portion, • a step d2) for eliminating halogenated compounds by passing said first portion through at least one suitable guard bed, • a water gas shift step d3) carried out on the effluent obtained from step d2), • a step d4) for catalytic hydrolysis of the COS and HCN compounds contained in said complementary portion of the effluent obtained from step d1) into H 2 S and NH 3, • a step d1) for scrubbing with water and for fractionating said synthesis gas into at least two effluents: a first portion and a complementary portion, • a step d2) for eliminating halogenated compounds by passing said first portion through at least one suitable guard bed, • a water gas shift step d3) carried out on the effluent obtained from step d2), • a step d4) for catalytic hydrolysis of the COS and HCN compounds contained in said complementary portion of the effluent obtained from step d1) into H 2 S and NH 3, e) a step for recombination of at least one fraction of each of the effluents obtained from steps d3) and d4), f) a step for scrubbing the recombined effluent obtained from step e) with water in order to eliminate impurities such as NH 3 and HCl, g) a step for elimination of the acid gases CO 2 and H 2 S contained in the effluent from step f) with one or more chemical or physical solvents, used alone or as a mixture, h) a step for final purification over at least one guard bed in order to adsorb traces of impurities remaining in the synthesis gas obtained from step g), such as H 2 S, COS, HCN and NH 3, i) a catalytic Fischer-Tropsch synthesis reaction step carried out on the effluent obtained from step h).