James N Ware

US Patent:

40661245, Jan 3, 1978

Filed:

Dec 1, 1976

Appl. No.:

5/746554

Inventors:

Joseph T. Carlin - Houston TX
James W. Ware - Tulsa OK
Melvin E. Mills - Salem IL
John A. Wells - Houston TX

Assignee:

Texaco Inc. - New York NY

International Classification:

E21B 4322

US Classification:

166252

Abstract:

Primary anionic surfactants such as organic sulfonates are effective for recovering oil from subterranean formations only if the salinity and/or hardness of the formation water is relatively low. In petroleum formations containing high salinity, or hard water, either the high salinity water must be displaced by a preflush or the primary anionic surfactant must be used in conjunction with an effective solubilizing co-surfactant, such as ethoxylated alcohols or alkyl phenols, or alkyl or alkylaryl thiols, as well as sulfated or sulfonated, ethoxylated alcohols or alkyl phenols. Optimum performance is achieved if two or more samples of petroleum sulfonate having different equivalent weight ranges and distributions are blended in a ratio which requires the minimum amount of solubilizing cosurfactant to achieve a condition of borderline solubility in the particular formation water in which the surfactants are to be employed. This ratio may be identified by preparing a number of blended petroleum sulfonate samples in the formation water using different ratios of total primary surfactant concentration to solubilizing co-surfactant concentration, and determining whether borderline solubility is achieved, by direct observation or by identifying the sample which produced the minimum electrical conductivity, or at which point the conductivity vs. concentration ratio curve exhibits an inflection point.

US Patent:

42149991, Jul 29, 1980

Filed:

Mar 20, 1978

Appl. No.:

5/888444

Inventors:

Joseph T. Carlin - Houston TX
James W. Ware - Tulsa OK
Melvin E. Mills - Salem IL
Timothy N. Tyler - Houston TX

Assignee:

Texaco Inc. - White Plains NY

International Classification:

E21B 4322

US Classification:

252 855D

Abstract:

Disclosed is a novel aqueous surfactant-containing fluid suitable for use in surfactant flooding oil recovery processes, and an oil recovery process using the fluid. The fluid contains petroleum sulfonates alone or in combination with solubilizing co-surfactants such as ethoxylated alkyl or alkylaryl compounds, alkyl or alkylaryl polyethoxy sulfates, or alkyl or alkylaryl polyethoxy sulfonates. The petroleum sulfonate is a mixture of petroleum sulfonates of varying equivalent weights ranging from 250 to 700, with an average equivalent weight between 325 and 425 and preferably between 350 and 400. Additionally, the distribution of equivalent weights is relatively uniform, with from 40 to 70 percent being less than 400 and from 60 to 30 percent of the petroleum sulfonates having equivalent weights being 400 or greater; and preferably from 15 to 35 percent of the petroleum sulfonates having equivalent weights less than 350, and 30 to 50 percent having equivalent weights from 350 to less than 500 and from 10 to 40 percent of the petroleum sulfonates having equivalent weights of 500 and above. The especially preferred embodiment employs a mixture of petroleum sulfonates in which 5 to 15 percent have equivalent weights less than 300, from 25 to 50 percent have equivalent weights the range of from about 300 to less than 400, from 15 to 25 percent fall in the range of from about 400 to less than 500 and from 5 to 20 percent have equivalent weights greater than 500.

US Patent:

41102290, Aug 29, 1978

Filed:

Dec 1, 1976

Appl. No.:

5/746646

Inventors:

Joseph T. Carlin - Houston TX
Timothy N. Tyler - Houston TX
Melvin E. Mills - Salem IL
James W. Ware - Tulsa OK

Assignee:

Texaco Inc. - New York NY

International Classification:

E21B 4322

US Classification:

252 855D

Abstract:

Disclosed is an aqueous, saline surfactant-containing fluid and an oil recovery process using the fluid for recovering oil from formations containing high salinity and/or high hardness water, the fluid comprising an anionic surfactant such as organic sulfonate especially petroleum sulfonates as well as synthetic alkyl or alkylaryl sulfonates and a solubilizing co-surfactants such as an ethoxylated alcohol, alkyl phenol, or alkyl or alkylaryl thiol, or sulfated or sulfonated, ethoxylated alcohols or alkyl phenols. Optimum performance in any particular field is achieved if the ratio of primary anionic surfactant to solubilizing co-surfactant is carefully chosen so the surfactant combination exhibits borderline solubility in the particular formation brine in which the surfactants are to be employed. The concentration ratio of primary and solubilizing surfactants which results in the desired borderline solubility may be identified by preparing a number of samples in the formation water using different weight ratios of primary surfactant to solubilizing co-surfactant concentration, and visually noting the minimum co-surfactant needed to avoid separation of the surfactant fluid into separate phases, or which gives the surfactant fluid a pearlescent, a swirl-silver appearance which is characteristic of fluids having the proper balance of primary anionic surfactant and solubilizing co-surfactant.