WETTABILITY AND PREDICTION OF OIL RECOVERY FROM RESERVOIRS DEVELOPED WITH MODERN DRILLING AND COMPLETION FLUIDS

Buckley, Jill S. ; Morrow, Norman R.

New Mexico Institute of Mining and Technology (United States)

关键词: Toluene;    02 Petroleum;    Amines;    Forecasting;    Flocculation;   

DOI  :  10.2172/822770
RP-ID  :  NONE
RP-ID  :  FC26-01BC15164
RP-ID  :  822770

美国|英语

来源: UNT Digital Library

【 摘 要 】

In this report we focus on surface studies of the wetting effects of SBM components; three areas of research are covered. First we present results of tests of interfacial properties of some commercial emulsifiers that are routinely used in both oil-based and synthetic oil-based drilling fluids. These products fall into two main groups, based on their CMC and IFT trends with changing pH. All can alter the wetting of mica, but measurements vary widely depending on the details of exposure and observation protocols. Non-equilibrium effects appear to be responsible for these variations, with equilibrated fluids generally giving lower contact angles than those observed with fluids that have not been pre-equilibrated. Addition of small amounts of emulsifier can increase the tendency of a crude oil to alter wetting of mica surfaces. The effects of similar amounts of these emulsifiers can be detected in interfacial tension measurements. Next, we report on the preliminary results of a study of polyethoxylated amines of varying structures on the wetting of mica surfaces. Contact angles have been measured for unequilibrated and pre-equilibrated fluids. Reduction in contact angles was generally observed when the surfaces were washed with toluene after exposure to surfactant solutions. Atomic forces microscopy is also being used to observe the interactions between these surfactants and mica surfaces. Finally, we show the results of a study of asphaltene stability in the presence of synthetic base oils. Most of the base oils in current use are paraffinic or olefinic--the aromatic content is minimized for environmental reasons--and they destabilize asphaltenes. Tests with two crude oils show onset conditions for base oils that are comparable to n-heptane and n-pentadecane in terms of the solubility conditions at the onset. Two ester-based products, Petrofree and Petrofree LV, did not cause asphaltene flocculation in these tests. A meeting of the research groups from New Mexico Tech and the University of Wyoming, was held in Laramie on the 9th and 10th of October. All the members of the research teams presented updates on their progress and exchanged views on directions for the remainder of the project.