SOCIETY OF PETROLEUM ENGINEERS OF AIME
6200 North Central Expressway
Dallas, Texas 75206
PAPER
NUMBER 3743
SPE
THIS IS
A PREPRINT - SUBJECT TO CORRECTION
PERFORMANCE OF OIL MUDS AT HIGH TEMPERATURES
by
N. ·E. Methven, Oil Base, Inc., Houston, U.S.A. and R. Baumann,
Oil Base Germany, Hamburg, Germany
©
Copyright 1972
American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.
This paper was prepared for the SPE-European Spring Meeting 1972 of the Society of Petroleum
Engineers of AIME, held in Amsterdam, The Netherlands, May 16-18, 1972. Permission to copy is
restricted to an abstract of not more than 300 words. Illustrations may not be copied. The 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 the SOCIETY OF
PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate
journal provided agreement to give proper credit is made.
Discussion of this paper is invited. Three copies of any discussion should be sent to the
Society of Petroleum Engineers, P.O.Box 228, The Hague, The Netherlands. Such discussion may be
presented at the above meeting and, with the paper, may be considered for publication in one of the
two SPE magazines.
The qata and analyses indicate that the
two bas:j.c oil mud types, oil base and in•
vert emulsion, have several distinct differ•
ences in performance characteristics at
high temperature. It appears that the invert
emulsion muds have temperature limits (at
least econ<?mic) because of thermal degrad•
ation of their synthetic organophilic colloids
and organic surfactants. Critical degrad•
ABSTRACT
This paper presents data on the perform•
ance of oil muds at high temperatures and
highpressures. Includedaredataand dis•
cussions regarding static densities, circu•
lating densities, thermal stability and
stability in corrosive environments.
The information on static and circulating
densities combines PVT data, recently
published methods of computing downhole
transient and pseudo-steady state tempera•
ture data as functions of circulating rates
and geothermal gradients, and recently
available rheological properties of oil
muds at high temperatures and pressures.
ation may occur in
500°F,
a matter of hours at
Oil base muds that use certain asphalts
for the colloidal material have higher
temperature stability. This is because the
asphalt does not degrade, at least up to
540°F, and, because the asphalt is hydro•
a
a
carbon, does not need synthetic oil wetting
and is in itself an emulsifier, and oil wet•
ting agent and surfactant.
Thermal stability of various oil muds
are discussed on the basis of theoretical
physiochemical behavior of the constitu•
ents as well as on the basis of laboratory
aging and rheology data. In addition, data
on oil base mud in the presence of hydrogen
sulfide and carbon dioxide are presented.
HelercnC'cs and JlluslrnhonH nl. end ol paper.