SOCIETY OF PETROLEUM ENGINEERS OF AIME
6300 North Central Expressway
Dallas, Tex.
NPAUMPEBRER SPE- 280
THIS IS
A PREPRINT --- SUBJECT TO CORRECTION
AQUAL IN® BlOC IDE
IN INJECTION WATERS
By
R. M. Jorda and L. T. Shearer,
Shell Development Co., Houston, Tex.
product should not greatly change the chemical
ABSTRACT
AQUALIN
and physical properties of the water, other than
to destroy the bacteria. The most important prop•
erties which should not be altered are pH, surfacel
and interfacial tension, and viscosity so that
further treatment will not be needed to alle','i::;;::'
®
Biocide, a Shell Chemical Co. for•
mulation consisting of 85 per cent by weight
acrolein, has been used with unusual success in
injection waters for control of microorganisms.
Complete control of various strains of bacteria
has been experienced in all cases in which tests
have been made. Injection of acrolein in low
concentrations into anaerobic injection water
the changes. Hundreds of bactericides have been
i
studied within Shell research groups to find
a
product meeting these requirements. Our findings
relating to the effectiveness of acrolein are
systems is accomplished with
ment pump. The results of the laboratory and
field experiments are presented, and chemical
a positive displace• described in this paper.
OCCURRENCE AND CONTROL OF WATER-BORNE
MICROORGANISMS
feeding
are described.
Water treating to control microorganisms is
highly selective problem. For example, bacter
INTRODUCTION
a
All industries' that utilize large amounts of
water have encountered microbiological problems
of varying degrees. However, only in recent
ial contamination of the same degree may be
tolerated in one system but not in another. Con•
sequently, each water considered for use mU2t be
tested separately. If bacteria are present, and
the nature of the system is conducive to their
growth, it must further be determined what
damage, if any, can be expected. If bacteria
problems are anticipated, suitable r;t',,('.tericides
must be chosen. Knowledge of the occurrence of
years has the petroleum industry
the
problems created by bacterial organisms in oil•
field water treating. With the advent of large•
scale secondary recovery by means of waterflood•
ing, larger
of water have been both
produced and injected. The bacteria problem was
originally ignored in many of these operations,
and only when serious problems were encountered
did the oil industry becoI:le aware of the effect
of microorganisms in water systems.
microorganisms in
for investigating Se
,
provides
,)blems.
a SOUllL. )"sis
The number of m',cL'oorganisms which exist in
waters considered fr,e use in water fJ_oods and
disposal systems --:tries greatly. The type of
With the recognition of the microbial prob•
lems of water injection came the investigation of system
control measures. In early investigations, poi•
sons were found to be ineffective because of the are generally conducive to the growth of lron
the types of organisms
and the'problems they present. Aerobic systems
ability of microbes to develop immunities.
Further study revealed that cationic organics,
ammonium chlorides,
and other amines, provided good control of the
most troublesome organisms, but the cost was high
and the bactericide-selection procedure was
lengthy. During the last decade, bacteria con•
trol in oil-field operations has generally been
achieved with amines.
bacteria, fungi, algae, and capsulated bacteria.
The iron bacteria are probably the most important
of these, since they can produce very tenacious,
gelatinous slimes of ferric hydrate capable of
fouling water lines and plugging injection wells.
These bacteria can grow in waters containing less
than one to over eight parts per million oxygen,
such as diamines,
but they
iron salts to sustain their
metabolism.
If bacterial action in any system is severe
enough to interfere with operations, it follows
that a "universal", inexpensive bactericide to
Algae
direct exposure to sunlight
and
a
source of carbon dioxide to Eustain photo-
synthesis, but they do not require direct ex•
posure to the atmosphere, as do the molds and
fungi. These microorganisms usually produce large
-
eliminate the problem would be desirable. This
References and illustrations at end of paper.