초록 ▼

A method of separating CO2 from a hydrocarbon gas inlet stream that is within predetermined pressure and temperature ranges, including the steps of subjecting the inlet stream to fractional distillation providing a CO2 bottom product stream and a distillation overhead stream, passing the distillatio

A method of separating CO2 from a hydrocarbon gas inlet stream that is within predetermined pressure and temperature ranges, including the steps of subjecting the inlet stream to fractional distillation providing a CO2 bottom product stream and a distillation overhead stream, passing the distillation overhead stream to the inlet of a primary reflux drum producing a primary reflux liquid stream and a hydrocarbon vapor stream, subjecting the hydrocarbon vapor stream to membrane separation to provide a hydrocarbon product stream and a permeate stream, compressing the permeate stream and recycling the compressed permeate stream to the inlet of the primary reflux drum thereby providing a CO2 liquid product and a hydrocarbon gas product.

대표청구항 ▼

What is claimed is: 1. A method of separating CO2 from a hydrocarbon gas inlet stream that is within predetermined pressure and temperature ranges, comprising the steps of: (a) subjecting the inlet stream to fractional distillation providing a CO2 bottom product stream and a distillation overhead s

What is claimed is: 1. A method of separating CO2 from a hydrocarbon gas inlet stream that is within predetermined pressure and temperature ranges, comprising the steps of: (a) subjecting the inlet stream to fractional distillation providing a CO2 bottom product stream and a distillation overhead stream; (b) passing the distillation overhead stream to the inlet of a primary reflux drum producing a primary reflux liquid stream and a hydrocarbon vapor stream; (c) subjecting the hydrocarbon vapor stream from step (b) to membrane separation to provide a hydrocarbon product stream and a permeate stream; (d) compressing the permeate stream from step (c) to provide a compressed permeate stream; and (e) recycling the compressed permeate stream from step (d) to said inlet of said primary reflux drum thereby providing a primary reflux liquid stream and a hydrocarbon gas product vapor stream. 2. A method of separating CO2 from a hydrocarbon gas inlet stream according to claim 1 including: passing said CO2 bottom product stream from step (a) to a reboiler separator that provides a reboiler separator vapor stream directed to a bottom portion of said distillation column and a reboiler separator liquid stream. 3. A method of separating CO2 from a hydrocarbon gas inlet stream according to claim 2 wherein said CO2 bottom product stream from step (a) is pumped at increased pressure to said reboiler separator. 4. A method of separating CO2 from a hydrocarbon gas inlet stream according to claim 2 including the step of passing at least a portion of said reboiler separator liquid stream through a pressure reduction device to reduce the pressure thereof and adding heat thereto to provide a CO2 gas product. 5. A method of separating CO2 from a hydrocarbon gas inlet stream that is within predetermined pressure and temperature ranges comprising the steps of: (a) subjecting the inlet stream to fractional distillation in a distillation column providing a CO2 bottom product stream and a distillation overhead stream; (b) subjecting said distillation overhead stream of step (a) to membrane separation, providing a hydrocarbon gas product stream and a permeate stream; (c) compressing said permeate stream to provide a compressed permeate stream; and (d) refluxing said compressed permeate stream from step (c) through a primary reflux drum having a primary reflux liquid stream outlet in communication with said distillation column. 6. A method of separating CO2 from a hydrocarbon gas inlet stream according to claim 5, including between steps (c) and (d) the additional step of passing said compressed permeate stream through a secondary reflux drum. 7. A method of separating CO2 from a hydrocarbon gas inlet stream according to claim 5 including: subjecting at least a portion of said CO2 bottom product stream from step (a) to reduced pressure to provide a CO2 gas product. 8. A method of separating CO2 from a hydrocarbon gas inlet stream according to claim 7 including the step of: passing a portion of said CO2 bottom product stream through a pressure reduction device through at least one heat exchanger used to adjust the temperature range of said hydrocarbon inlet stream. 9. A method of separating CO2 from a hydrocarbon gas inlet stream that is within predetermined pressure and temperature ranges, including the steps of: (a) subjecting the inlet stream to a distillation column producing a bottom product stream and a distillation overhead stream; (b) condensing said distillation overhead stream of step (a) in a primary reflux drum producing a primary reflux liquid stream and a hydrocarbon vapor stream; (c) recycling said primary reflux liquid stream of step (b) to said distillation column as a reflux stream; (d) separating said concentrated hydrocarbon vapor stream from step (b) by membrane separation into a hydrocarbon gas product stream and a permeate stream; (e) compressing said permeate gas stream from step (d) to produce a compressed permeate stream; (f) condensing said compressed permeate stream of step (e) to produce a primary reflux liquid stream that is conveyed to an upper portion of said distillation column; (g) pumping said bottom product stream from step (a) to provide an elevated pressure liquid CO2 product; and (h) subjecting said bottom product stream of step (a) to a reboiler separator to produce a CO2 liquid product and a reboiler separator vapor stream that is recycled to a bottom portion of said distillation column. 10. A system for separating CO2 from a hydrocarbon gas inlet stream that is within predetermined pressure and temperature ranges, comprising: a distillation column receiving the hydrocarbon gas inlet stream and providing a CO2 bottom product stream and a distillation overhead stream; a primary reflux drum having an inlet receiving the distillation overhead stream and producing a primary reflux liquid stream and a hydrocarbon vapor stream; a membrane unit receiving the hydrocarbon vapor stream from said primary reflux drum to provide a hydrocarbon gas product stream and a permeate stream; a compressor receiving said permeate stream from said membrane unit to provide a compressed permeate stream; and piping to recycle said compressed permeate stream to said inlet of said primary reflux drum thereby providing a liquefied CO2 product and a hydrocarbon gas product. 11. A system of separating CO2 from a hydrocarbon gas inlet stream according to claim 10 including: a reboiler separator having an inlet that receives said CO 2 bottom product stream from said distillation column and that provides a reboiler separator vapor stream to a bottom portion of said distillation column and a CO2 liquid product. 12. A system for separating CO2 from a hydrocarbon gas inlet stream according to claim 10 including; a CO2 bottom product pump in line with said CO2 bottom product stream to increase the pressure within said reboiler separator. 13. A system of separating CO2 from a hydrocarbon gas inlet stream according to claim 10 including a primary refrigerant pressure reduction device through which at least a portion of said CO 2 liquid product from said reboiler separator is passed to reduce the pressure thereof and add heat thereto to provide a CO2 gas product. 14. A system for separating CO2 from a hydrocarbon gas inlet stream that is within prescribed pressure and temperature ranges comprising: a distillation column for receiving and fractionally distilling the hydrocarbon gas inlet stream providing a CO2 liquid product and a distillation overhead stream; a membrane unit receiving the distillation overhead stream and providing a hydrocarbon gas product and a permeate stream; a compressor receiving the permeate stream and providing a compressed permeate stream; and a primary reflux drum receiving said compressed permeate stream providing a primary reflux liquid stream that is refluxed back into said distillation column. 15. A system for separating CO2 from a hydrocarbon stream according to claim 14 including a secondary reflux drum that receives said compressed permeate stream and that provides a secondary reflux liquid stream that is refluxed to said distillation column. 16. A system for separating CO2 from a hydrocarbon stream according to claim 14 including a primary refrigerant pressure reduction device through which at least a portion of said CO2 bottom product stream is passed to reduce the pressure thereof to provide a CO2 gas product. 17. A system for separating CO2 from a hydrocarbon inlet stream according to claim 16 including an inlet cross heat exchanger through which said CO2 gas product from said refrigerant pressure reduction device passes and through which the hydrocarbon inlet stream passes to thereby serve to adjust the temperature range of the hydrocarbon inlet stream.