Abstract: A method can include receiving, by a demulsifier analysis framework, tensiometer data for an oil and water field sample that includes an added candidate demulsifier, where the tensiometer data include rheology data with respect to frequency and where the demulsifier analysis framework includes a model derived at least in part on bottle test data for demulsifiers in oil and water emulsions; determining a performance characteristic for the candidate demulsifier with respect to the oil and water field sample using the tensiometer data as input to the model of the demulsifier analysis framework without performing a bottle test on the oil and water field sample; and outputting, by the demulsifier analysis framework, the performance characteristic for the candidate demulsifier with respect to breaking an emulsion of the oil and water field sample.

Abstract: Methods may include emplacing a downhole tool within a wellbore, sampling a fluid downhole with the downhole tool; analyzing the fluid, and calculating an interfacial tension (IFT), wherein calculating the acid-base IFT contribution comprises measuring a concentration of a surface-active species directly. Apparatuses for measuring an interfacial tension (IFT) in a fluid downhole may be part of a downhole tool and may include a sampling head to sample the fluid; and a downhole fluid analysis module that includes a spectrometer capable of measuring a concentration of a surface-active species in the fluid, and a processor configured to determine the IFT of the fluid downhole based on the measured concentration of the surface-active species.

Abstract: A downhole tool has a tool body with an outer diameter equal to a borehole diameter, at least one cavity formed in and opening to an outer surface defining the outer diameter of the tool body, a light source, a filter, and a light detector mounted in the at least one cavity, and a window disposed at the opening of the at least one cavity, wherein the window encloses the cavity.

Abstract: Methods and systems are provided for characterizing interfacial tension (IFT) of reservoir fluids, which involves obtaining fluid property data that represents fluid properties of a reservoir fluid sample measured downhole at reservoir conditions, and inputting the fluid property data to a computational model that determines a value of oil-water IFT of the reservoir fluid sample based on the fluid property data. In embodiments, the fluid property data represents single-phase fluid properties of the reservoir fluid sample, such as fluid density and viscosity of an oil phase of the reservoir fluid sample and fluid density of a water phase of the reservoir fluid sample. In embodiments, the computation model can be based on machine learning or analytics combined with a thermodynamics-based physics model.

Abstract: A downhole tool has a tool body with an outer diameter equal to a borehole diameter, at least one cavity formed in and opening to an outer surface defining the outer diameter of the tool body, a light source, a filter, and a light detector mounted in the at least one cavity, and a window disposed at the opening of the at least one cavity, wherein the window encloses the cavity.

Abstract: Methods and systems are provided for characterizing interfacial tension (IFT) of reservoir fluids, which involves obtaining fluid property data that represents fluid properties of a reservoir fluid sample measured downhole at reservoir conditions, and inputting the fluid property data to a computational model that determines a value of oil-water IFT of the reservoir fluid sample based on the fluid property data. In embodiments, the fluid property data represents single-phase fluid properties of the reservoir fluid sample, such as fluid density and viscosity of an oil phase of the reservoir fluid sample and fluid density of a water phase of the reservoir fluid sample. In embodiments, the computation model can be based on machine learning or analytics combined with a thermodynamics-based physics model.

Abstract: A method for determining thermal maturity of a formation sample. The method includes: cleaning the formation sample to remove residues of drilling fluid and reservoir fluid to obtain a cleaned sample; performing Raman spectroscopic measurements on the cleaned sample to obtain a Raman spectrum for the cleaned sample; fitting at least a G (graphite) peak and a D1 (defect) peak to the Raman spectrum to obtain Raman shift values for the G peak and the D1 peak and a Raman band separation (RBS) value; using the RBS to generate a vitrinite reflection equivalent (VRe) value using a relationship correlating RBS to VRe; and displaying the VRe as an indicator of formation sample maturity for a depth in the formation from which the cleaned sample was obtained.

Abstract: 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.

Abstract: Methods may include emplacing a downhole tool within a wellbore, sampling a fluid downhole with the downhole tool; analyzing the fluid, and calculating an interfacial tension (IFT), wherein calculating the acid-base IFT contribution comprises measuring a concentration of a surface-active species directly. Apparatuses for measuring an interfacial tension (IFT) in a fluid downhole may be part of a downhole tool and may include a sampling head to sample the fluid; and a downhole fluid analysis module that includes a spectrometer capable of measuring a concentration of a surface-active species in the fluid, and a processor configured to determine the IFT of the fluid downhole based on the measured concentration of the surface-active species.

Abstract: A method for determining thermal maturity of a formation sample. The method includes: cleaning the formation sample to remove residues of drilling fluid and reservoir fluid to obtain a cleaned sample; performing Raman spectroscopic measurements on the cleaned sample to obtain a Raman spectrum for the cleaned sample; fitting at least a G (graphite) peak and a D1 (defect) peak to the Raman spectrum to obtain Raman shift values for the G peak and the D1 peak and a Raman band separation (RBS) value; using the RBS to generate a vitrinite reflection equivalent (VRe) value using a relationship correlating RBS to VRe; and displaying the VRe as an indicator of formation sample maturity for a depth in the formation from which the cleaned sample was obtained.

Abstract: A downhole tool has a tool body with an outer diameter equal to a borehole diameter, at least one cavity formed in and opening to an outer surface defining the outer diameter of the tool body, a light source, a filter, and a light detector mounted in the at least one cavity, and a window disposed at the opening of the at least one cavity, wherein the window encloses the cavity.

Abstract: 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.