In displacement processes for recovery of liquid hydrocarbons from a hydrocarbon bearing formation having zones of different permeability wherein such displacement processes comprise injecting a drive fluid through an injection well vertically traversing the formation and recovering by means of a production well the liquid hydrocarbons which are displaced by the injection of the drive fluid; this invention involves an improvement comprising injecting a water insoluble liquid into the permeable zone to increase drive efficiency in the less permeable zone.
Disclosed is a process for removing contaminants from a contaminated area of the subsurface which comprises providing a borehole in the contaminated area; placing in the borehole a perforated riser pipe inside of which is situated a vacuum extraction pipe with an opening situated within the perforated riser pipe, wherein a packing is situated in a portion of the annular space between the vacuum extraction pipe and the perforated riser pipe; applying a vacuum to the vacuum extraction pipe to draw gases and liquid from the subsurface into the perforated riser pipe below the packing and from the riser pipe into the vacuum extraction pipe and transport both the gases and the liquid to the surface as a common stream; forming from the common stream a stream which is primarily liquid and a stream which is primarily gaseous; and removing contaminants from at least one of the liquid stream and the gaseous stream. Also disclosed is an apparatus for carrying out the disclosed process.
Disclosed is a process and apparatus for removing contaminants from a contaminated area of the ground, the ground having a plurality of paths of preferential flow at different depths, which process comprises providing a borehole in the contaminated area to intersect at least a first path of preferential flow and a second path of preferential flow; placing in the borehole a first vacuum extraction pipe having a bottom opening situated within the first path of preferential flow and a second vacuum extraction pipe having a bottom opening situated within the second path of preferential flow; isolating the first path of preferential flow from the second path of preferential flow so that a vacuum applied to the first vacuum extraction pipe will extract gases and liquids from only the first path of preferential flow, and a vacuum applied to the second vacuum extraction pipe will extract gases and liquids from only the second path of preferential flow; applying a vacuum to at least one of the vacuum extraction pipes to draw gases and liquid from at least one of the paths of preferential flow into a vacuum extraction pipe and transport the gases and liquid to the surface as a common stream; forming from the common stream a stream which is liquid and a stream which is gaseous; and removing contaminants from the liquid and/or gaseous streams.
