Marathon Oil Company

Other

Hiemi K Haines

Gary R Kennedy

Richard D Favinger

Sidney R Smith

Richard L Christiansen

Douglas E Kenyon

Donald C McClure

Lance J Galvin

Teresa G Monger

Hung-Lung Chen

An apparatus and process for observing fluid replacement in core samples while simulating subsurface reservoir conditions, including oil composition, temperature, fluid pressure, and overburden pressure. Overburden pressure is applied to a core sample placed in the apparatus, and the core sample is saturated with a core saturating fluid at a pressure greater than the bubble point pressure of the core saturating fluid. One or more replacement fluids are provided in fluid communication with the core sample and at the same pressure as the core saturating fluid pressure. The apparatus is placed in a centrifuge and spun, and the extent and rate of replacement of the core saturating fluid in the core by a replacement fluid can be observed.

Method and apparatus for core flooding studies

A process for recovering oil from a multiple-layered heterogeneous reservoir with a higher oil saturation in the lower permeability layers than in the higher permeability layers. An aqueous surfactant solution is injected into the formation, where it imbibes into the lower permeability layers and displaces a first quantity of oil into the higher permeability layers. Next, a first aqueous fluid is injected to sweep the displaced oil from the higher permeability layers into at least one production well. A gas is injected into the formation to displace a second quantity of oil from the lower permeability layers. The second aqueous fluid is injected to sweep the displaced oil into at least one production well. The process may be repeated one or more times.

Enhanced oil recovery from heterogeneous reservoirs

A bucket for use in a swinging bucket centrifuge. A core holder is located between two end chambers, with the annular space between the core holder and the bucket sidewall maintaining the chambers in fluid communication. Windows at each end of the bucket allow fluid collections to be monitored. This enables more accurate data to be obtained regarding the effect of fluids of different specific gravity on a fluid saturating a sample. For example, to obtain data allowing a more accurate modeling of reservoir conditions in an oil field impacted by both gas and water displacement, the amount of oil expelled from a rock sample by gas under pressure and temperature conditions simulating those in the reservoir is measured and, after replacing the gas with water, the amount of oil expelled by water under simulated conditions is measured.

Centrifuge bucket and method of use

A process for in-situ enrichment of gas used in miscible flooding in a subterranean hydrocarbon-bearing reservoir. A drive gas such as methane, lean natural gas, nitrogen, carbon dioxide or mixtures thereof is used to immiscibly displace formation hydrocarbons. After gas breakthrough the produced fluid is separated into oil and gas components. The separated gas, which has been enriched with intermediate hydrocarbon compounds extracted from the formation hydrocarbons, is mixed with the drive gas injected into the reservoir so as to enrich the injected gas sufficiently to cause miscible displacement of the formation hydrocarbons. When the drive gas is carbon dioxide, methane and/or nitrogen may be extracted from the separated gas prior to being mixed with the drive gas.

Process for in-situ enrichment of gas used in miscible flooding

A process for the enhanced recovery of liquid hydrocarbons from a subterranean hydrocarbon-bearing formation wherein natural gas which is immiscible with the liquid hydrocarbons is injected into the formation via a well. The well is shut in for a period of time to permit the natural gas to render the liquid hydrocarbons mobile and thereafter the mobilized liquid hydrocarbons are produced from the well.

Enhanced liquid hydrocarbon recovery process

A process for enriching a drive gas with intermediate hydrocarbon compounds to enhance the ability of the gas to mobilize hydrocarbons within a subterranean hydrocarbon-bearing formation. The drive gas is contacted with oil containing intermediate hydrocarbons under conditions such that the gas strips intermediate hydrocarbons from the oil. The drive gas may be further enriched upon contacting the gas with stripped oil which has been enriched with intermediate hydrocarbons under conditions such that the gas strips intermediate hydrocarbons from the enriched stripped oil.

Process for enriching a gas

A zone of a subterranean formation containing a low-viscosity crude oil which has already been waterflooded to completion is sequentially flooded with alternating slugs of produced gas and water to produce incremental amounts of the oil. The zone is characterized as a low-permeability zone having mixed geology, i.e., containing two or more rocks of differing permeability randomly distributed throughout the zone.

Growing community of inventors

Englewood, CO, United States of America

Hiemi K Haines