Lorne A. Davis

Determination of Oil Saturation Distributions in Field Cores By Microwave Spectroscopy

Two microwave adsorption spectrometers have been developed for routine monitoring of oil saturation (S/sub o/) distributions during laboratory flooding experiments in field core material. Operating frequencies are 10.525 and 24.125 GHz. A core sample cell has been designed which permits S/sub o/ distributions to be determined in narrow rectangular and cylindrical cores. An indirect calibration technique has been developed. Details of the instrumentation are presented with a theoretical description of instrumental response. The practical utility of this instrumentation for the a priori detection of core defects and quantitative determination of porosity distributions is demonstrated. 20 refs.

Computer-Controlled Measurement of Laboratory Areal Flood Saturation Distributions

A microcomputer controlled microwave absorption instrument has been developed for automated measurement of laboratory linear and areal flood oil/water saturation distributions. The instrument design and performance characteristics are given in detail, and the roles of micro, mini and mainframe computers in data collection and analysis are described. Much of the design criteria and features are applicable to other oil recovery laboratory experimentation. An applications study is presented in a companion paper, SPE 12038. An error analysis study of experimental saturation distribution data is used to identify localized structured water present in a linear core at residual oil saturation to chemical flood. Comparison is made to the residual microemulsion phase predicted by a simulator study of the experiment.

Characterization of Surfactants Using a Scaling Law Interpretation of Coreflood Residual Oil Saturation Profiles

The characterization of surfactant candidates for a given reservoir can be improved by the use of linear coreflood residual-oil-saturation profiles measured along the core after chemical flooding. A surfactant formulations functional relation of oil recovery to slug size can be calculated from a single coreflood with the assumption of a relaxed scaling law. A volumetric linear scaling approach is developed from laboratory coreflood data. Residual-oil-saturation profiles measured in reservoir material with a microwave absorption instrument support this approximate scaling relation. Analysis of 32 linear surfactant-slug corefloods is presented as additional verification. The limits of this scaling law are defined, with emphasis on the role of mixing and dispersion. The procedure for using saturation profiles to calculate oil recovery as a function of slug size is developed and a test case is presented. A recovery relation derived from a single coreflood saturation profile is compared with that determined by multiple conventional corefloods.

Multiple Slug Scaling of Linear and Pattern Laboratory Chemical Floods

This work presents the concept of multiple slug scaling and demonstrates its ability to predict oil recovery in laboratory linear floods. A theoretical basis for the application of multiple slug scaling to pattern flood predictions is discussed, and the behavior of one laboratory pattern flood is compared to predictions made by this theory. 8 refs.

A Comparison of Laboratory Linear and Pattern Flow Chemical Floods Using a Volumetric Linear Scaling Concept for Oil Saturation Distributions

A laboratory quarter five-spot pattern chemical flood was conducted in a consolidated, homogeneous porous matrix for comparison with standard linear core floods. In addition to the routine material balance information, quatitative areal oil saturation isometric and contour plots were obtained from microwave attenuation measurements made during the flood. A volumetric linear scaling approach was used to predict the behavior of the pattern chemical flood from linear flood data. An interpretation of the pattern flood response is proposed in terms of the scaling theory, its assumptions and its limitations. 8 refs.