Biocides - A Case History Study At The Rangely Weber Sand Unit
Authors: Conger H.C. , Bass W.R. , Butler P.J. 
Published: December 2007

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This paper is to be presented at the 38th Annual Fall Meeting of the Society of Petroleum Engineers of AIME in New Orleans, La., on October 6–9, 1963, and is considered the property of the Society of Petroleum Engineers. Permission to publish is hereby restricted to an abstract of not more than 300 words, with no illustrations, unless the paper is specifically released to the press by the Editor of the JOURNAL OF PETROLEUM TECHNOLOGY or the Executive Secretary. Such abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or SOCIETY OF PETROLEUM ENGINEERS JOURNAL is granted on request, providing proper credit is given that publication and the original presentation of the paper.
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Abstract
The presence of sulfate reducing bacteria and the resulting problems of corrosion and iron sulfide deposition in water flooding have received much attention in the past few years. This case history discusses field experience In defining and solving a sulfate reducing bacteria problem.
The methods employed early in the flood in attempting to solve the bacterial problem in the Navajo-Entrada fresh water are discussed. This case history illustrates how, as a result of these methods, a well-planned program was evolved which finally solved the problem.
The adaptation of this program for solving the sulfate reducing bacteria problem in the Weber produced water is also discussed.
Types of water tests and resulting data are outlined and discussed. Types of biocides used are summarized and specific factors influencing their performance are discussed.

Introduction
Dealing with water problems is relatively foreign to the background and experience of the petroleum engineer and there has been a tendency to minimize the importance of water treatment. Consequently in a majority of cases, the trial and error method was adopted as a means of solving water problems.
Solving a water problem demands the same engineering approach or planned program as any other operational problem. The problem must be defined. Valid and relative data must be collected, interpreted and evaluated by qualified individuals. A field testing program should be initiated and the data collected and evaluated. After the final treatment program is initiated, it must be followed by a continuous monitoring program.
NAVAJO-ENTRADA FRESH WATER

Background
The Rangely field was unitized in Oct., 1957. Fig. 1 is a current map of the field.
The following pilot injection projects were initiated early in 1958:
Injection Well Field Location Source Water Weyrauch 3–36 East end J.E. Pepper A-1 Entrada formation
Batty Fairfield North central S.A. Guiberson B-1 periphery A-2 Navajo formation