초록 ▼

Disclosed herein is a process for conditioning natural gas containing C3+ hydrocarbons, so that it can be used as combustion fuel to run gas-powered equipment, including gas engines and turbine-driven compressors, in the gas field or the gas processing plant. The claimed process use glassy polymeric

Disclosed herein is a process for conditioning natural gas containing C3+ hydrocarbons, so that it can be used as combustion fuel to run gas-powered equipment, including gas engines and turbine-driven compressors, in the gas field or the gas processing plant. The claimed process use glassy polymeric membranes that are preferentially permeable to methane over C2+ hydrocarbons to produce a partially purified methane stream. The process operates at a stage cut of at least about 5%.

대표청구항 ▼

1. A pro cress for conditioning a portion of a gas stream, the gas stream comprising at least methane and C2+ hydrocarbons and the process comprising the following steps: (a) withdrawing the portion from the high-pressure gas stream;(b) providing a membrane unit having a feed side, a permeate side,

1. A pro cress for conditioning a portion of a gas stream, the gas stream comprising at least methane and C2+ hydrocarbons and the process comprising the following steps: (a) withdrawing the portion from the high-pressure gas stream;(b) providing a membrane unit having a feed side, a permeate side, and a residue side, and containing a membrane selective for methane over C2+ hydrocarbons;(c) passing the portion as a feed stream across the feed side under conditions in which transmembrane permeation occurs;(d) withdrawing from the residue side a membrane residue stream;(e) withdrawing from the permeate side a membrane permeate stream enriched in methane and depleted in C2+ hydrocarbons compared with the feed stream; and(f) routing the membrane permeate stream as a portion of a fuel gas stream to a fuel user, wherein the process operates at a stage cut of at least 5%. 2. The process of claim 1, wherein the portion is passed to a pre-treatment step before being routed to the membrane unit. 3. The process of claim 2, wherein the pre-treatment step is select d from the group consisting of a filtration step, a heating step, and a combination thereof. 4. The process of claim 1, wherein the membrane residue stream is routed back to the gas stream. 5. The process of claim 4, wherein the membrane residue stream is routed back to the gas stream upstream of where the portion is withdrawn. 6. The process of claim 4, wherein the membrane residue stream is routed back to the gas stream downstream of where the portion is withdrawn. 7. The process of claim 1, wherein the membrane residue stream is partially condensed and recovered as C2+ hydrocarbon liquids. 8. The process of claim 1, wherein the fuel user comprises power generation equipment. 9. The process of claim 1, wherein the fuel user is a gas engine. 10. The process of claim 1, wherein the fuel user drives a compressor. 11. The process of claim 10, wherein the gas stream is a high-pressure gas stream created by a compressor driven by a gas engine, and wherein step (f) comprises using the membrane permeate stream as fuel for the gas engine. 12. The process of claim 1, wherein the membrane comprises a polymer having the formula: where x and y represent the relative proportions of the dioxo e and the tetrafluoroethylene blocks, such that X+y=1. 13. The process of claim 1, wherein the membrane comprises a polymer having the formula: where n is a positive integer. 14. The process of claim 1, wherein the membrane comprises a polymer having the formula: where x and y represent the relative proportions of the dioxole and the tetrafluoroethylene blocks, such that x+y=1. 15. The process of claim 1, wherein the stage cut is at least 8%.