US Patent 7506690 Enhanced liquid hydrocarbon recovery by miscible gas injection water drive

In distinct embodiments, miscible gas is injected directly into crude oil within its formation, entering into solution within it at optimum pressures, adding desired solution gas saturation, increasing its mobility and fluidity. This mobile solution gas saturated oil is produced by controlled wellbore to formation pressures maintained above its critical bubble point pressure, from same injection wells converted into oil recovery wells, where liquids only are differential pressure injected through invention's improved Liquid Injector DOLI, into the production tubing, while maintaining gas volume, pressure, and solution gas saturation in the formation, for total in place oil recovery.