Integrated processes and systems for conversion of methane to multiple higher hydrocarbon products
Integrated systems are provided for the production of higher hydrocarbon compositions, for example liquid hydrocarbon compositions, from methane using an oxidative coupling of methane system to convert methane to ethylene, followed by conversion of ethylene to selectable higher hydrocarbon products. Integrated systems and processes are provided that process methane through to these higher hydrocarbon products.
1. A method of generating a plurality of hydrocarbon products, comprising:
(a) providing an oxidative coupling of methane (OCM) product stream comprising ethylene (C 2 H 4 );
(b) splitting said OCM product stream into two or more portions of said OCM product stream; and
(c) directing said two or more portions of said OCM product stream into a plurality of ethylene conversion reactors comprising a first ethylene conversion reactor and a second ethylene conversion reactor, wherein (i) said first ethylene conversion reactor permits a first portion of said two or more portions of said OCM product stream to react in a first ethylene conversion process to generate a first product stream comprising a first set of higher hydrocarbon products and (ii) said second ethylene conversion reactor permits a second portion of said two or more portions of said OCM product stream to react in a second ethylene conversion process to generate a second product stream comprising a second set of higher hydrocarbon products, wherein said first set of higher hydrocarbon products have different higher hydrocarbon products or higher hydrocarbon product distributions than said second set of higher hydrocarbon products, thereby generating said plurality of hydrocarbon products.
2. The method of claim 1 , wherein (a) further comprises, directing methane and an oxidant into an OCM reactor that permits at least a portion of said methane and said oxidant to react in an OCM reaction to generate said OCM product stream.
3. The method of claim 1 , wherein at least a subset of said plurality of ethylene conversion reactors are separate from and operate in a parallel configuration with respect to one another.
4. The method of claim 2 , wherein said plurality of ethylene conversion reactors is fluidly coupled to said OCM reactor.
5. The method of claim 2 , wherein said plurality of ethylene conversion reactors is integrated with said OCM reactor.
6. The method of claim 2 , wherein said two or more portions of said OCM product stream are directed from said OCM reactor into said plurality of ethylene conversion reactors without passing through intermediate reactors.
7. The method of claim 1 , wherein said plurality of hydrocarbon products comprises C 3 to C 30 compounds.
8. The method of claim 1 , wherein said OCM product stream comprises between about 0.5% and about 15% of ethylene.
9. The method of claim 2 , wherein said OCM reaction is performed at a reactor inlet temperature between about 450° C. and 600° C., and a pressure between about 15 pounds per square inch gauge (psig) and 125 psig, with a C 2+ selectivity of at least about 50%.
10. The method of claim 1 , further comprising, prior to (c), preheating said OCM product stream to about 200° C. to 500° C.
11. The method of claim 2 , further comprising, between (a) and (b), directing said OCM product stream into an ethylene recovery reactor fluidly coupled to said OCM reactor, wherein said ethylene recovery reactor enriches said C 2 H 4 in said OCM product stream.
12. The method of claim 1 , further comprising combining said first product stream and said second product stream into a stream comprising said plurality of hydrocarbon products.
13. The method of claim 12 , further comprising directing said stream into at least one heat exchanger to reduce a temperature of said stream.
14. The method of claim 12 , further comprising heating said OCM product stream using heat obtained from said stream.
15. The method of claim 1 , further comprising directing said plurality of hydrocarbon products into a fractionation unit to produce one or more members selected from the group consisting of (i) gasoline (ii) jet fuel (iii) diesel fuel (iv) fuel blendstocks and (v) aromatics.
16. The method of claim 1 , wherein said plurality of ethylene conversion reactors comprises solid catalysts.
17. The method of claim 16 , wherein at least a subset of said plurality of ethylene conversion reactors comprise different solid catalysts.
18. The method of claim 16 , wherein said solid catalysts comprise one or more catalysts selected from the group consisting of zeolites ZSM-5, Y, Beta, ZSM-22, ZSM-48, SAPO-34, SAPO-5, SAPO-11, Mordenite, Ferrierite, SBA-15, SBA-16, MCM-22, MCM-41, and Al-MCM-41.
19. The method of claim 1 , wherein at least a subset of said plurality of ethylene conversion reactors are operated under different reaction conditions.
20. The method of claim 1 , further comprising directing said plurality of hydrocarbon products into a hydrogenation unit to hydrogenate olefins from said plurality of hydrocarbon products to paraffins or isoparaffins using a hydrogenation catalyst.