Steam-Hydrocarbon Reforming Process

摘要

A steam-hydrocarbon reforming process utilizing a prereformer where a portion of the effluent from the prereformer is conditioned and the C2+ hydrocarbon content in the conditioned effluent measured. The molar flow rate of steam to the prereformer is increased or decreased responsive to measuring the C2+ hydrocarbon content of the conditioned effluent.

主权项

1. A steam-hydrocarbon reforming process comprising:
passing a feed stream to a first reactor containing a catalyst during a first period, reacting the feed stream in the first reactor in the presence of the catalyst under reaction conditions sufficient to react the feed stream and form an intermediate product stream, and withdrawing the intermediate product stream from the first reactor;
wherein the feed stream comprises steam and hydrocarbons including C2+ hydrocarbons, wherein the concentration of the C2+ hydrocarbons in the feed stream varies during the first period;wherein the feed stream has a molar flow rate of hydrocarbons, FHC; andwherein the feed stream has a molar flow rate of steam, FS, thereby defining a ratio, FS/FHC, of the molar flow rate of steam to the molar flow rate of hydrocarbons in the feed stream; dividing the intermediate product stream into a first portion and a second portion, the second portion of the intermediate product stream having a mass flow rate, M1; introducing a second reactor feed stream comprising the first portion of the intermediate product stream into a second reactor, reacting the second reactor feed stream in the second reactor in the presence of a second catalyst under reaction conditions effective to form a reformate comprising H2, CO, CH4, and H2O, and withdrawing the reformate from the second reactor; conditioning the second portion to remove at least water and ammonia and form a conditioned portion of the second portion of the intermediate product stream; measuring a C2+ hydrocarbon content in the conditioned portion of the second portion of the intermediate product stream in a chemical component analyzer; increasing the ratio of the molar flow rate of steam to the molar flow rate of hydrocarbons in the feed stream responsive to the step of measuring the C2+ hydrocarbon content when the C2+ hydrocarbon content equals or exceeds an upper target C2+ hydrocarbon content during the first period; and decreasing the ratio of the molar flow rate of steam to the molar flow rate of hydrocarbons in the feed stream responsive to the step of measuring the C2+ hydrocarbon content when the C2+ hydrocarbon content equals or drops below a lower target C2+ hydrocarbon content during the first period.