Coil-wound heat exchanger for hydrotreatment or hydroconversion

Process for hydroconversion or hydrotreatment of a hydrocarbon feedstock, comprising the following steps:

• heating and directly distributing the hydrocarbon feedstock and optionally a hydrogen stream or a hydrocarbon feedstock/hydrogen stream mixture to a hydrotreatment or hydroconversion reaction section (R-1) by means of at least one coil-wound heat exchanger (S-1);
• mixing the hydrocarbon feedstock with the hydrogen stream in a first mixing section, said mixing taking place before or after the heating step;
• cooling the reaction effluent from the hydrotreatment or hydroconversion reaction section (R-1) by means of the at least one coil-wound heat exchanger (S-1), said coil-wound exchanger being a single-pass heat exchanger formed by a vertical chamber in which one or more bundles of tubes are helically wound around a central core, as numerous superposed layers;
• hydrotreating or hydroconverting the hydrocarbon feedstock in the hydrotreatment or hydroconversion reaction section (R-1) comprising at least one reactor comprising at least one catalyst comprising at least one element chosen from elements from Group VIII of the Periodic Table;
• separating at least one portion of the cooled reaction effluent in a high-pressure cold separator (B-2) in order to distribute a first liquid effluent comprising at least one light fraction and a first gaseous effluent comprising hydrogen;
• and
• separating the first liquid effluent comprising at least one light fraction in a separation column (C-1) in order to distribute a bottoms liquid and an overhead effluent.