A method for safely disposing of a waste gas from produced hydrocarbons. The waste gas is mixed with a surfactant to form a foam which, in turn, is placed within a disposal zone of a subterranean formation. The waste gas is effectively "trapped" within the foam thereby substantially reducing the mobility of the gas in the formation which, in turn, restricts the ability of the waste gas to readily flow out of the disposal zone and into the producing zone of the formation. The waste gas foam can be placed into the formation by coinjecting the surfactant and the waste gas or it can be formed in situ by first injecting the surfactant and then injecting the waste gas.
The invention is a method and system of separating a multi-component fluid in a wellbore. At least one fluid separation membrane comprising a feed side and a permeate side is incorporated in the wellbore. A flowing stream of the multi-component fluid obtained from a subterranean zone being in fluid communication with the wellbore is passed across the feed side of the membrane at a first pressure. A retentate stream depleted in at least one component compared to the multi-component fluid is withdrawn from the feed side of the membrane and passed to the earth's surface. A permeate stream at a second pressure is withdrawn from the permeate side, in which the permeate stream is enriched in at least one component compared with the multi-component fluid. The second pressure is controlled to maintain the second pressure below the first pressure.
This invention is method of recovering gas from a gas-bearing subterranean formation in which gas is produced from an upper portion of the formation and a waste gas is injected into a lower portion of the formation to dispose of the waste gas. The waste gas is injected within a 3000 foot (914 m) radial distance from the production of the gas. The injection and production can be carried out using one well or a plurality of wells.
