Abstract:
Methods for obtaining in-situ, multi-temperature measurements of fluid properties, such as saturation pressure and asphaltene onset pressure include obtaining a sample of formation fluid using a downhole acquisition tool positioned in a wellbore in a geological formation. The downhole acquisition tool may be stationed at a first depth in the wellbore that has an ambient first temperature. While stationed at the first depth, the downhole acquisition tool may test a first fluid property of the sample to obtain a first measurement point at approximately the first temperature. The downhole acquisition tool may be moved to a subsequent station at a new depth with an ambient second temperature, and another measurement point obtained at approximately the second temperature. From the measurement points, a temperature-dependent relationship of the first fluid property of the first formation fluid may be determined.
Abstract:
Embodiments of the disclosure can include systems, methods, and devices for determining saturation pressure of an uncontaminated fluid. Downhole saturation pressure measurements and downhole OBM filtrate contamination of a contaminated fluid may be obtained and a relationship may be determined between the saturation pressure measurements and OBM filtrate contamination. The relationship may be extrapolated to zero OBM filtrate contamination to determine the saturation pressure of the uncontaminated fluid. In some embodiments, OBM filtrate contamination may be determined from downhole saturation pressure measurements during pumpout of a fluid.
Abstract:
Embodiments of the disclosure can include systems, methods, and devices for determining saturation pressure of an uncontaminated fluid. A technique facilitates fluid analysis in situ at a downhole location. Downhole saturation pressure measurements and downhole OBM filtrate contamination of a contaminated fluid may be obtained and a relationship may be determined between the saturation pressure measurements and OBM filtrate contamination. The relationship may be extrapolated to zero OBM filtrate contamination to determine the saturation pressure of the uncontaminated fluid. According to an embodiment, a sample of oil is obtained at the downhole location from oil in a reservoir. A downhole sampling system is used to determine whether a sample has contamination and other selected characteristics of the sample. The data obtained may be processed to provide a formation volume factor of the oil.
Abstract:
Embodiments of the disclosure can include systems, methods, and devices for determining saturation pressure of an uncontaminated fluid. Downhole saturation pressure measurements and downhole OBM filtrate contamination of a contaminated fluid may be obtained and a relationship may be determined between the saturation pressure measurements and OBM filtrate contamination. The relationship may be extrapolated to zero OBM filtrate contamination to determine the saturation pressure of the uncontaminated fluid. In some embodiments, OBM filtrate contamination may be determined from downhole saturation pressure measurements during pumpout of a fluid.
Abstract:
Embodiments of the disclosure can include systems, methods, and devices for determining saturation pressure of an uncontaminated fluid. Downhole saturation pressure measurements and downhole OBM filtrate contamination of a contaminated fluid may be obtained and a relationship may be determined between the saturation pressure measurements and OBM filtrate contamination. The relationship may be extrapolated to zero OBM filtrate contamination to determine the saturation pressure of the uncontaminated fluid. In some embodiments, OBM filtrate contamination may be determined from downhole saturation pressure measurements during pumpout of a fluid.
Abstract:
Methods for obtaining in-situ, multi-temperature measurements of fluid properties, such as saturation pressure and asphaltene onset pressure include obtaining a sample of formation fluid using a downhole acquisition tool positioned in a wellbore in a geological formation. The downhole acquisition tool may be stationed at a first depth in the wellbore that has an ambient first temperature. While stationed at the first depth, the downhole acquisition tool may test a first fluid property of the sample to obtain a first measurement point at approximately the first temperature. The downhole acquisition tool may be moved to a subsequent station at a new depth with an ambient second temperature, and another measurement point obtained at approximately the second temperature. From the measurement points, a temperature-dependent relationship of the first fluid property of the first formation fluid may be determined.
Abstract:
Methods and systems for determining for determining asphaltene onset pressure of a formation fluid are described herein. The method includes the following processes: (a) transmitting light through a sample of the formation fluid; (b) decreasing pressure of the sample; (c) detecting intensity of the transmitted light during depressurization; (d) identifying a change in intensity of the transmitted light during depressurization; (e) increasing pressure of the sample to a fixed pressure; and (f) detecting intensity of the transmitted light at the fixed pressure and at an equilibrated light intensity. Processes (a) to (f) are repeated for a number of different fixed pressures. The asphaltene onset pressure of the formation fluid sample can be determined using (i) the intensity of the transmitted light during each depressurization and (ii) the intensity of the transmitted light at each of the different fixed pressures.
Abstract:
Embodiments of the disclosure can include systems, methods, and devices for determining saturation pressure of an uncontaminated fluid. Downhole saturation pressure measurements and downhole OBM filtrate contamination of a contaminated fluid may be obtained and a relationship may be determined between the saturation pressure measurements and OBM filtrate contamination. The relationship may be extrapolated to zero OBM filtrate contamination to determine the saturation pressure of the uncontaminated fluid. In some embodiments, OBM filtrate contamination may be determined from downhole saturation pressure measurements during pumpout of a fluid.
Abstract:
A method and an apparatus for characterizing a fluid including a phase transition cell to receive the fluid, a piston to control fluid pressure, a pressure gauge to measure the fluid pressure and to provide information to control the piston, and connectors to connect the cell, piston, and gauge. The exterior volume of the phase transition cell, piston, gauge, and connectors is less than about 10 liters. A method and an apparatus to characterize a fluid including observing a fluid in an phase transition cell, measuring a pressure of the fluid, and adjusting a pressure control device in response to the measuring.