HYDRODESULPHURISATION PROCESS

摘要

A hydrodesulphurisation process for continuously effecting hydrodesulphurisation of a liquid sulphur-containing hydrocarbon feedstock comprises: (a) providing a plurality of hydrodesulphurisation zones connected in series each containing a packed bed of a solid sulphided hydrodesulphurisation catalyst, said plurality of hydrodesulphurisation zones including a first hydrodesulphurisation zone and at least one other hydrodesulphurisation zone including a final hydrodesulphurisation zone; (b) maintaining temperature and pressure conditions in each hydrodesulphurisation zone effective for hydrodesulphurisation of the liquid feedstock; (c) supplyinmg liquid sulphur-containing hydrocarbon feedstock to the first hydrodesulphurisation zone; (d) passing the liquid feedstock through the plurality of hydrodesulphurisation zones in turn from the first hydrodesulphurisation zone to the final hydrodesulphurisation zone; (e) passing hydrogen-containing gas through the hydrodesulphurisation zones from one zone to another; (f) contacting the liquid feedstock with hydrogen under hydrodesulphurisation conditions in each hydrodesulphurisation zone in the presence of the respective charge of hydrodesulphurisation catalyst; and which further comprises: (i) supplying make up hydrogen to a hydrodesulphurisation zone other than the first hydrodesulphurisation zone; (ii) recovering a hydrogen-containing gas from each hydrodesulphurisation zone; (iii) supplying the first hydrodesulphurisation zone with hydrogen-containing gas recovered from a subsequent hydrodesulphurisation zone; (iv) purging hydrogen-containing gas recovered from the first hydrodesulphurisation zone; (v) supplying any other hydrodesulphurisation zone other than the first hydrodesulphurisation zone and other than the hydrodesulphurisation zone of step (i) with hydrogen-containing gas recovered from another hydrodesulphurisation zone; (vi) monitoring the sulphur content of the hydrogen-containing gas and of the liquid hydrocarbon feedstock supplied to the first hydrodesulphurisation zone; and (vii) supplying, if necessary, sulphur-containing material selected from H2S and active sulphur-containing materials to the first hydrodesulphurisation zone so as to maintain the catalyst charge thereof in sulphided form.