Abstract: A sample is placed in a sample housing. The sample includes crude oil and a demulsifier. A cylindrical sensor is submerged in the sample within the sample housing. An external surface of the cylindrical sensor includes a fluoropolymer. A plurality of densities of the sample are measured by a computer for a corresponding plurality of time points over a specified testing time duration. The computer is communicatively coupled to the cylindrical sensor. The plurality of densities and the corresponding plurality of times points are recorded by the computer. An emulsion breaking efficiency of the demulsifier is determined based on the recorded plurality of densities and corresponding plurality of time points.

Abstract: A method for quantifying a crude oil in water is provided. The method includes selecting an ultraviolet/visible (UV/Vis) wavelength to perform a measurement, preparing calibration solutions in xylene, and preparing a calibration curve from the calibration solutions. A sample is prepared including extracting the crude oil from the water in a two-phase separation with xylene. An absorbance of the sample in the xylene is measured at the UV/Vis wavelength. A concentration of the crude oil in the water is calculated from the absorbance.

Abstract: A drag reducing efficiency test is performed on a sample. The sample includes a crude-oil based fluid and a drag reducing agent. The sample is placed within an inner volume defined by a sample housing. A sensing portion of a sensor is submerged in the sample within the sample housing. The sensor includes a disk (sensing portion) and a supporting rod. A lid is placed on the sample housing to isolate the sample within the inner volume. The sensor is coupled to an air bearing motor. The sensor is rotated by the air bearing motor at a plurality of shear rates. For each shear rate, the sensor measures a torque applied by the sample on the disk in response to the disk rotating while submerged in the respective sample at the respective shear rate.

Abstract: A sample is placed in a sample housing. The sample includes crude oil and a demulsifier. A cylindrical sensor is submerged in the sample within the sample housing. An external surface of the cylindrical sensor includes a fluoropolymer. A plurality of densities of the sample are measured by a computer for a corresponding plurality of time points over a specified testing time duration. The computer is communicatively coupled to the cylindrical sensor. The plurality of densities and the corresponding plurality of times points are recorded by the computer. An emulsion breaking efficiency of the demulsifier is determined based on the recorded plurality of densities and corresponding plurality of time points.

Abstract: A method for quantifying a crude oil in water is provided. The method includes selecting an ultraviolet/visible (UV/Vis) wavelength to perform a measurement, preparing calibration solutions in xylene, and preparing a calibration curve from the calibration solutions. A sample is prepared including extracting the crude oil from the water in a two-phase separation with xylene. An absorbance of the sample in the xylene is measured at the UV/Vis wavelength. A concentration of the crude oil in the water is calculated from the absorbance.

Abstract: Systems and methods for evaluating a drag reducing agent's performance in a mixture are described. The system includes a measuring instrument with an rheometer; and a sensor system positioned inside the measuring instrument including a body with an open end and an extended end, wherein the extended end is directly attached to the measuring instrument; a cover with an inner disc and an outer disc and attachable to the body, the inner disc sized to be received by the open end of the body; the body and the cover form a sealable chamber; and a rotating disc with a bar and a plate, the bar is attached to the measuring instrument and the plate is positioned inside the body and operable to measure drag reducing agent's performance of the mixture; and a data acquisition and processing system is in electronic communication with the measuring instrument, and the sensor system.

Abstract: Tools, methods, and systems for evaluating a demulsifier performance from an emulsion mixture are described. The systems include a measuring instrument including a body with an open end, a cover attachable to the body, a sample holder sized to hold the emulsion mixture and to be received inside the body, the body and the cover define a sealable chamber; a sensor system positioned inside the sealable chamber an environmental control system positioned to enclose the sealable chamber; a data acquisition and processing system is in electronic communication with the sealable chamber, the sensor system, and the environmental control system. The sensor system includes a handle attached to and extruding from the cover of the measuring instrument; and a sensor loaded onto the handle, sized to be submerged inside the emulsion mixture of the sample holder, and operable to measure performance of the demulsifier.