CPC C10G 35/02 (2013.01) [C10G 35/24 (2013.01); C10G 63/02 (2013.01); C10G 2300/4006 (2013.01); C10G 2300/4012 (2013.01)] | 8 Claims |
1. A reforming process for upgrading a heavy naphtha feedstock, comprising:
feeding the heavy naphtha feedstock to a first stage consisting of dehydrogenating naphthenes in the heavy naphtha feedstock in one or more dehydrogenation reactors of a three-stage reforming system to form a first effluent stream comprising aromatics, wherein the dehydrogenation is conducted at a pressure ranging from 1 to 20 bars, at a temperature ranging from 400 to 450° C., and with a hydrogen to hydrocarbon molar ratio ranging from 6 to 8, and
wherein the dehydrogenation is conducted at a liquid hourly space velocity ranging from 0.5 h−1 to 2 h−1;
flowing the first effluent stream to a second stage comprising separating extracted aromatics from raffinate paraffins via extraction of the extracted aromatics from the first effluent stream to produce a second effluent stream containing the raffinate paraffins, wherein separating the extracted aromatics from the raffinate paraffins comprises:
separating the first effluent stream into a reformate stream and a hydrogen gas stream, wherein the hydrogen gas stream is split and a portion of the hydrogen gas stream is recycled back to the heavy naphtha feedstock and the remaining portion is directed away from the reforming to a refining unit, and
extracting the extracted aromatics from the reformate stream in an aromatic extraction unit of the three-stage reforming system, thereby providing the second effluent stream containing at least 95 wt % raffinate paraffins; and
flowing the second effluent stream to a third stage comprising subjecting the second effluent stream to cyclization reactions in one or more cyclization reactors of the three-stage reforming system to produce a third effluent stream comprising aromatics, wherein the first effluent stream and the third effluent stream are combined prior to extraction,
wherein the cyclization reactions are conducted at a LHSV ranging from 0.5 h−1 to 2 h−1, and
wherein the cyclization reactions are at a temperature ranging from 480 to 520° C.
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