Abstract: The present invention provides methods and apparatus for separating and/or analyzing fluids of interest. According to principles of the present invention, fluid analysis is accomplished with microfluidic devices and may be reported in real-time or near real-time in a subterranean environment. In addition or alternative to oilfield applications, the principles of the present invention contemplate separation in a laboratory or other environment for biological sample separation and analytical chemistry applications. The present invention is capable of separating liquid-liquid mixtures or emulsions in a microfluidic device without fouling.

Abstract: A sensor for installation in an underground well having a casing or tubing installed therein, the sensor comprising: a sensor body that can be installed in a hole formed in the casing or tubing so as to extend between the inside and outside of the casing or tubing; sensor elements located within the body and capable of sensing properties of an underground formation surrounding the well; and communication elements located within the body and capable of communicating information between the sensor elements and a communication device in the well; wherein the sensor body also includes a portion that can be sealed to the casing or tubing to prevent fluid communication between the inside and the outside of the casing or tubing through the hole when the sensor body is installed therein. The invention also provides systems incorporating such sensors, methods for installing sensors and applications of such systems.

Abstract: Improved methods, apparatus, and systems for obtaining information regarding a formation, a casing, or fluid within the casing utilize an interrogator and one or more sensing devices attached to a casing in a wellbore. The interrogator, which is located and typically movable inside the wellbore, is effectively a toroidal transformer which includes an elongate conducting body surrounded by a core of high magnetic permeability material and carrying a winding. The sensing device, which is positioned and fixed in an opening cut in the casing, includes a housing, a sensor with associated electronic circuitry and an electrode. The electrode is insulated from the casing by an insulator, and the housing of the sensing device is typically adapted to provide a hydraulic seal with the opening in the casing. The interrogator and sensing device communicate in a wireless manner.

Abstract: A device for determining the mean resistivity of a multiphase fluid having a continuous conductive phase, includes a pipe segment (4) of insulating material and a oil (6) for generating an electric current in the fluid flowing along the pipe. The device has two measurement electrodes (10, 11) spaced apart in the axial direction of the insulating segment to measure the electrical resistance between said two electrodes, the measurement electrodes being applied to the outside of the wall of the segment to perform measurement by capacitive coupling. The voltage between the measurement electrodes is measured. The device is particularly useful for determining the volume fraction (“holdup”) of water in a mixture of water and hydrocarbons.

Abstract: The invention relates to a tool holder serving to receive measurement means (9, 10, 13) for characterizing a multi-phase fluid coming from a deposit (17) through which at least one well (16) passes, and flowing inside said tool holder. According to the invention, the tool holder is provided with an axial cavity (3) and with a first radial opening (4) which opens out in the inside wall of said tool holder and intercepts said axial cavity, said cavity and said opening serving to receive said measurement means. The invention also relates to a device for characterizing a multi-phase fluid coming from a deposit (17) through which at least one well (16) passes, said device comprising: a source unit (9) for emitting gamma rays through said multi-phase fluid, and a detector unit (10) having a scintillator crystal (10a) receiving said gamma rays after they have passed through the fluid.

Abstract: The invention relates to a device for measuring an electrical parameter through electrically-conductive casing, said device including a current injection electrode (3) and a measurement electrode (7) on one side of the wall of the casing (1). According to the invention, the injection electrode (3) is associated via a first magnetic coupler (4) with a current source (2) and the measurement electrode (7) is associated via a second magnetic coupler (6) with a measurement device (5) situated on the other side of the wall.

Abstract: Methods, apparatus, and systems for obtaining information regarding a formation, a casing, or fluid within the casing are provided which utilize an interrogator and one or more sensing devices attached to a casing in a wellbore. The interrogator is located within and may be movable inside the wellbore. The sensing device is positioned and fixed in an opening in the casing. The sensing device includes a housing and a sensor with associated electronic circuitry. The interrogator and sensing device include a magnetic coupling therebetween that is operable when the interrogator and sensing device are positioned in close proximity to one another. Preferably, the magnetic coupling is realized by at least one solenoid winding for the interrogator and at least one solenoid winding for the sensing device, which provide a loosely-coupled transformer interface therebetween. The interrogator and sensing device communicate in a wireless manner over the magnetic coupling therebetween.

Abstract: Methods, apparatus, and systems for obtaining information regarding a formation, a casing, or fluid within the casing are provided which utilize an interrogator and one or more sensing devices attached tod a casing in a wellbore. The interrogator, which is located and typically movable inside the wellbore, is effectively a toroidal transformer which includes an elongate conducting body surrounded by a core of high magnetic permeability material and carrying a winding. The sensing device, which is positioned and fixed in an opening cut in the casing, includes a housing, a sensor with associated electronic circuitry and an electrode. The electrode is insulated from the casing by an insulator, and the housing of the sensing device is typically adapted to provide a hydraulic seal with the opening in the casing. The interrogator and sensing device communicate in a wireless manner.

Abstract: An indicator mixture that allows pH measurement over a broader range of pH or to a higher accuracy than available using conventional spectroscopic techniques. In particular, the mixture of the present invention is comprised of two or more reagents such that when combined, the reagent mixture is capable of either detecting: (1) a pH range broader or more accurate than that the reagents individually, or (2) pH more accurately than the reagents individually. Also disclosed are methods of making and using the mixture.

Abstract: The invention relates to a tool holder serving to receive measurement means (9, 10, 13) for characterizing a multi-phase fluid coming from a deposit (17) through which at least one well (16) passes, and flowing inside said tool holder. According to the invention, the tool holder is provided with an axial cavity (3) and with a first radial opening (4) which opens out in the inside wall of said tool holder and intercepts said axial cavity, said cavity and said opening serving to receive said measurement means. The invention also relates to a device for characterizing a multi-phase fluid coming from a deposit (17) through which at least one well (16) passes, said device comprising: a source unit (9) for emitting gamma rays through said multi-phase fluid, and a detector unit (10) having a scintillator crystal (10a) receiving said gamma rays after they have passed through the fluid.

Abstract: The invention relates to a device for measuring an electrical parameter through electrically conductive casing, said device including a current injection electrode (3) and a measurement electrode (7) on one side of the wall of the casing (1). According to the invention, the injection electrode (3) is associated via a first magnetic coupler (4) with a current source (2) and the measurement electrode (7) is associated via a second magnetic coupler (6) with a measurement device (5) situated on the other side of the wall.

Abstract: The invention relates in particular to a device for determining the mean resistivity of a multiphase fluid having a continuous conductive phase, the device including a pipe segment (4) of insulating material and means (6) for generating an electric current in the fluid flowing along the pipe. The device has two measurement electrodes (10, 11) spaced apart in the axial direction of the insulating segment to measure the electrical resistance between said two electrodes, the measurement electrodes being applied to the outside of the wall of the segment to perform measurement by capacitive coupling, and the device further having means (12-22) for measuring the voltage between the measurement electrodes. The invention is applicable to determining the volume fraction (“holdup”) of water in a mixture of water and hydrocarbons.