Schlumberger Technology Corporation

Saudi Arabian Oil Company

University of Strathclyde

Mikhail Stukan

Wael Abdallah

Patrice Ligneul

Reza Taherian

Andrew Emil Pomerantz

Andrew Clarke

Stephen Dyer

Ahmed Gmira

Albina Mutina

Bastian Sauerer

Raphael Altman

Johannes J M Buiting

Maxim Fedorov

Methods may include measuring an interfacial tension (IFT) for a dead oil sample prepared from a fluid within an interval of a formation; calculating a gas:oil ratio for the fluid within the interval of a formation at a specified temperature and pressure; calculating a live oil density for the fluid within the interval of a formation for the specified temperature and pressure; and converting the IFT for the dead oil sample to a corrected IFT measurement for a live oil within the interval of the formation from the calculated gas:oil ratio and the calculated density. Methods may also include constructing a depletion path for the dead oil sample from one or more isobars and one or more isotherms; and converting the IFT for the dead oil sample to a corrected IFT measurement from the calculated gas:oil ratio and the calculated live oil density for a live oil.

Method for prediction of live oil interfacial tension at reservoir conditions from dead oil measurements

A method and apparatus for measuring interfacial or surface tension of a first fluid dispersed in a second fluid, the method involving providing at least one substantially spherical droplet or bubble of the first fluid in a flowing stream of the second fluid in a flow channel, followed by passing the flowing stream comprising the droplet or bubble through a constriction in the flow channel, the constriction being sufficiently constricting so as to cause the droplet or bubble to deform away from its substantially spherical shape and measuring and comparing a physical property of the flowing stream both before and after the constriction, wherein the physical property changes as a result of the deformation of the droplet or bubble, and thereby inferring the interfacial or surface tension from the measured physical property.

Determination of interfacial or surface tension

Injection fluid tuning is provided. In one possible implementation, injection fluid can be tuned by accessing both surface properties of rock found in a hydrocarbon reservoir of interest and a chemical composition of oil found in the reservoir of interest. An ion effect on wettability of a contact surface of the rock can be acquired and then used to formulate a tuned ion solution based on the ion effect on wettability of the contact surface of the rock. In another possible implementation, an electrolyte solution has an ionic composition and an ionic concentration configured to enhance recovery of oil from a reservoir. The electrolyte solution includes a content of direct contact ions including monovalent ions with a static polarizability larger than a preset limit sufficient to influence a contact surface of a rock in the reservoir to reach a desired wettability.

Injection fluid tuning

Various implementations directed to determining a phase behavior of a reservoir fluid are provided. In one implementation, a method may include receiving a plurality of predetermined pore size data, a plurality of predetermined bulk fluid data, and a plurality of predetermined kerogen data that are based on historical data for a plurality of hydrocarbon reservoirs. The method may also include creating a library of a plurality of simulated phase behavior data for the predetermined pore size data, the predetermined bulk fluid data, and the predetermined kerogen data. The method may further include determining a phase behavior of a reservoir fluid disposed in an actual hydrocarbon reservoir using the library.

Determining phase behavior of a reservoir fluid

An instrument (and corresponding method) performs AFM techniques to characterize properties of a sample of reservoir rock. The AFM instrument is configured to have a probe with a tip realized from reservoir rock that corresponds to the reservoir rock of the sample. The AFM instrument is operated to derive and store data representing adhesion forces between the tip and the sample at one or more scan locations in the presence of a number of different fluids disposed between the tip and the sample. The AFM instrument is further configured to perform computational operations that process the data representing the adhesion forces for a given scan location in order to characterize at least one property of the rock sample at the given scan location. The properties can include total surface energy of the rock sample as well as wettability of the rock sample.

Measurement of surface energy components and wettability of reservoir rock utilizing atomic force microscopy

A protocol for determining the effect of water composition on surface alteration is described using simple and less preparation sensitive, brine/oil and rock/brine/air systems when compared to conventional rock/brine/oil measurement methods. A model glass/brine/oil system is described and it is demonstrated that experimental measurements of contact angle obtained using a conventional approach agree well with the contact angles predicted using the proposed protocol.

Methods for determining wettability alteration

Systems and methods for analyzing produced fluids in a mature water flood (or EOR scheme) and determining whether the introduction of an EOR agent, such as a chemical or a gas additive, or some other alteration in treatment, is enhancing the recovery of hydrocarbon from parts of the reservoir otherwise untouched by injected fluids. The monitoring can be used to identify subtle changes in the produced fluid caused by their flow through different pore structures. In a carbonate formation for example, ions and salts from the rock fabric are dissolved into the reservoir fluids, whether they are water or oil. These can be detected by various fluid analysis and particularly water analysis methods. The changes in reservoir fluid paths associated with the injection of an EOR agent are detected in the observation well.

Flowpath identification and characterization

A method is described for selecting an additive for enhanced recovery from a subterranean hydrocarbon reservoir including the steps of using a set of parameters to determine, at a first level of molecular dynamic modeling, an effect of the additive on interfacial tension between a hydrocarbon and water/brine; using the effect of the additive on interfacial tension derived from the first level of molecular dynamic modeling to determine, at a second coarser level of molecular dynamic modeling wettability effects; and using the effect of the additive on interfacial tension derived from the first level of molecular dynamic modeling and the wettability effects derived from the second level of molecular dynamic modeling to determine at a third coarser level of molecular dynamic modeling imbibition or drainage effects.

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Al-Khobar, Saudi Arabia

Mikhail Stukan