The systems and method described in this specification relate to a method for determining a residual oil saturation of a reservoir. The method includes obtaining a plurality of rock samples from the reservoir; determining a permeability of each of the rock samples; measuring a fluid viscosity of oil in the reservoir; estimating a location-specific permeability of the reservoir across the reservoir based on the permeability of each of the rock samples; determining a location-specific displacing velocity of the reservoir based on a function of the location-specific permeability and the fluid viscosity of the oil; determining the residual oil saturation of the reservoir based on the location-specific displacing velocity using Franklin's equation; and predicting a recovery of the oil from the reservoir using the residual oil saturation in a computational model of the reservoir.

The systems and method described in this specification relate to a method for determining a residual oil saturation of a reservoir. The method includes obtaining a plurality of rock samples from the reservoir; determining a permeability of each of the rock samples; measuring a fluid viscosity of oil in the reservoir; estimating a location-specific permeability of the reservoir across the reservoir based on the permeability of each of the rock samples; determining a location-specific displacing velocity of the reservoir based on a function of the location-specific permeability and the fluid viscosity of the oil; determining the residual oil saturation of the reservoir based on the location-specific displacing velocity using Franklin's equation; and predicting a recovery of the oil from the reservoir using the residual oil saturation in a computational model of the reservoir.

The invention relates to the technical field of oilfield exploration, and discloses a 4D quantitative and intelligent diagnosis method and system for spatio-temporal evolution of oil-gas reservoir damage types and extent. The method includes: determining a characteristic parameter characterizing reservoir damage by each of a plurality of factors based on a spatio-temporal evolution simulation equation of reservoir damage by each of the plurality of factors; and determining an effective characteristic parameter characterizing the damage extent of the reservoir based on the characteristic parameter characterizing reservoir damage rby each of the plurality of factors. The invention can quantitatively simulate the characteristic parameters of reservoir damage caused by the various factors and a total characteristic parameter of the reservoir damage. Therefore for a well without reservoir damage, performing quantitative prediction of reservoir damage and spatio-temporal deduction of damage laws is of scientific guidance significance for preventing reservoir damage, and formulating development plans for oil pools and subsequent well stimulation measures, and for a well with reservoir damage, also performing quantitative diagnosis of reservoir damage and spatio-temporal deduction of damage laws achieves optimal design of a declogging measure and improvement or restoration of oil-gas well production and water well injection capacity.

The invention relates to the technical field of oilfield exploration, and discloses a 4D quantitative and intelligent diagnosis method and system for spatio-temporal evolution of oil-gas reservoir damage types and extent. The method includes: determining a characteristic parameter characterizing reservoir damage by each of a plurality of factors based on a spatio-temporal evolution simulation equation of reservoir damage by each of the plurality of factors; and determining an effective characteristic parameter characterizing the damage extent of the reservoir based on the characteristic parameter characterizing reservoir damage rby each of the plurality of factors. The invention can quantitatively simulate the characteristic parameters of reservoir damage caused by the various factors and a total characteristic parameter of the reservoir damage. Therefore for a well without reservoir damage, performing quantitative prediction of reservoir damage and spatio-temporal deduction of damage laws is of scientific guidance significance for preventing reservoir damage, and formulating development plans for oil pools and subsequent well stimulation measures, and for a well with reservoir damage, also performing quantitative diagnosis of reservoir damage and spatio-temporal deduction of damage laws achieves optimal design of a declogging measure and improvement or restoration of oil-gas well production and water well injection capacity.

Embodiments of the disclosure provide an asymmetrically functionalized nanoparticle and a method for synthesizing the same. The asymmetrically functionalized nanoparticle includes a base nanoparticle. The base nanoparticle can include silicon dioxide. The base nanoparticle can have a lipophilic surface. A portion of the surface can be functionalized with a functionalizing material forming a hydrophilic portion. The functionalizing material can include polyethylenimine. A remaining portion of the surface is not functionalized forming a lipophilic portion. The asymmetrically functionalized nanoparticle is amphiphilic.

An installation for storing, metering, and dissolving water-soluble polymer particles, in particular for enhanced oil and/or gas recovery operations, includes a so-called “polymer dissolution” container A and at least one so-called “polymer storage and distribution” container B positioned upon container A. The bottom of container B and the roof of container A each have an opening facing one another allowing the passage of the polymer from container B into the supply mechanism of container A. The installation further includes a connection mechanism able to work with the polymer supply mechanism.

An installation for storing, metering, and dissolving water-soluble polymer particles, in particular for enhanced oil and/or gas recovery operations, includes a so-called “polymer dissolution” container A and at least one so-called “polymer storage and distribution” container B positioned upon container A. The bottom of container B and the roof of container A each have an opening facing one another allowing the passage of the polymer from container B into the supply mechanism of container A. The installation further includes a connection mechanism able to work with the polymer supply mechanism.

A method for modifying surface wettability of a surface of a solid substrate may include contacting the surface of the solid substrate with a brine solution containing carbon nanodots. The carbon nanodots may have carbon, oxygen, nitrogen, and hydrogen as constituent elements and may include one or more functional groups disposed at outer surfaces of the carbon nanodots. The brine solution has a salinity of greater than 30,000 TDS. A concentration of carbon nanodots in the brine solution is less than or equal to 500 ppmw. Contacting the solid substrate with the brine solution comprising the carbon nanodots is characterized by a contact duration, a contact volume, or both, that is sufficient to reduce the oil wettability of the surface of the solid substrate by at least 15%, as defined by a contact angle of a crude oil droplet contacted with the surface of the solid substrate.

The present disclosure relates to a prediction method for constant production decline of a water-producing gas well in a highly heterogeneous reservoir. The prediction method mainly includes: collecting related data of a target water-producing gas well, fitting to obtain a water-drive constant and a water invasion constant, fitting dynamic reserves by adopting a Blasingame plotting method, conducting fitting by adopting a dual-medium model to obtain an elastic storativity ratio and an interporosity flow coefficient, calculating a reservoir heterogeneity coefficient, obtaining a flowing bottomhole pressure at the later stage of stable production, calculating formation pressure of a new day through quantitative production of the target water-producing gas well with 1 day as an iteration stride, performing iteration until the formation pressure is less than or equal to the formation pressure at the end of stable production, and drawing a prediction curve about constant production decline of the target water-producing gas well.

The present disclosure relates to a prediction method for constant production decline of a water-producing gas well in a highly heterogeneous reservoir. The prediction method mainly includes: collecting related data of a target water-producing gas well, fitting to obtain a water-drive constant and a water invasion constant, fitting dynamic reserves by adopting a Blasingame plotting method, conducting fitting by adopting a dual-medium model to obtain an elastic storativity ratio and an interporosity flow coefficient, calculating a reservoir heterogeneity coefficient, obtaining a flowing bottomhole pressure at the later stage of stable production, calculating formation pressure of a new day through quantitative production of the target water-producing gas well with 1 day as an iteration stride, performing iteration until the formation pressure is less than or equal to the formation pressure at the end of stable production, and drawing a prediction curve about constant production decline of the target water-producing gas well.