DEVICE FOR THE REMOVAL AND SEPARATION OF HELIUM ISOTOPES FROM NATURAL GAS

摘要

This disclosure presents a new device for the removal and separation of isotopes of Helium in Compressed Natural Gas, based on a system with two cascades operating together to increase, in the first cascade, the concentration of Helium in the cascade head, and at the tail of the same cascade, Helium-depleted Compressed Natural Gas is discharged, while the second cascade, fed from the head of the first cascade, allows separation of the isotopes of Helium-3 and Helium-4, discharging Helium-3 through the head of the second cascade, while Helium-4 is discharged through the tail of the second cascade, with a configuration that is efficient from the energy consumption standpoint, while using a small number of rotating parts.

主权项

1. A device for the removal and separation of helium isotopes from natural gas, to separate isotopes from a first gas, in relation to a second majority carrier gas at pressure, with higher molecular weight than the isotopes of the first gas, with increased commercial value when the content of the first gas decreases in the second majority carrier gas, comprising two cascades with serial stages each, with the first cascade operating at a pressure that is equal or lower to the pressure of the source providing the majority carrier gas, and allows enrichment of the content of the first gas in relation to the second majority carrier gas through selective permeability of the mixture of gasses, which, when going through successive membrane stages with higher permeability to the first gas in relation to the second majority carrier gas, a flow can be extracted of the majority carrier gas as output of the first cascade, with depletion of the content in the first gas, generating a first continuous flow of a product of commercial interest, while the second output of the first stream is enriched in the content of the first gas and feeds the second cascade at some intermediate point, and where this second cascade is at a pressure lower than the pressure operating the first cascade, to produce isotope separation of its gasses through diffusion of that gas through inert porous membranes, since the mean free paths of the gas of the second cascade is similar to the pore radius of the porous membranes, generating higher permeability for molecules and isotopes with lower molecular weight, so that at the end of the second cascade towards where gasses advance with lower molecular weight, an output flow is obtained enriched with the light isotope, generating in this flow a second continuous flow of a product of commercial interest, while at the other end of the second cascade in relation to the extraction point of the output enriched with the lighter isotope and the feed point, an output flow is obtained depleted in the light isotope, which generates a third continuous flow of a product of commercial interest.