| 摘要 |
<p>Hydrocarbon feedstock is cracked using a fluidised catalyst in apparatus which comprises (a) a reactor vessel (2) which has a riser cracking zone (6) which takes the form of a vertical tube whose downstream end is within the reactor; (b) primary cyclones (8,12) are connected to the downstream end of the riser and separate catalyst from the riser effluent; (c) secondary cyclones (10,14) are connected to the primary cyclones: the first enclosed conduit (16) linking the riser to the primary cyclones, and the second enclosed conduit (24,42) linking the primary and secondary cyclones, both isolate the material within the conduits from the atmosphere of the reactor; (d) a catalyst stripping zone (4) removes entrained hydrocarbons present in the separated catalyst from the primary cyclones; (e) openings (22,38) in the first enclosed conduit (16,36) allow steam and/or hydrocarbon gases to enter the primary cyclones; (f) surge capacity to accommodate sudden increased flow of catalyst by means of trickle valves (27,27A,41,41A) in the enclosed conduits.</p> |
