||Selecting Pipeline Corrosion Inhibitors in the Laboratory
A half-day workshop Evaluating and Qualifying Oilfield and Refinery
Corrosion Inhibitors in the Laboratory is being offered by ASTM
Committee G01 on Corrosion of Metals, 8 a.m., Wed., Nov. 7, in Dallas, Texas,
during their general meetings. There is no admission fee but pre-registration
is desired. The event is part of an ongoing effort by ASTM to
promote the use of state-of-the-art techniques for selection of
inhibitors by the oilfield and refinery industries. Following
the workshop, all are invited to attend a meeting on corrosion
inhibitors at 1 p.m. with ASTM G01.05.11.01.
The workshop will highlight ASTM G 170, Standard Guide for Evaluating and Qualifying Oilfield and Refinery
Corrosion Inhibitors in the Laboratory, just approved in May 2001.
Developed by oil companies, inhibitor suppliers, researchers,
consultants, and educators in ASTM Subcommittee G01.05 on Laboratory
Corrosion Tests, the standard promotes:
Selection of cost-effective, high-quality inhibitors for companies;
Design and manufacture of more efficient products by suppliers.
Oil and gas pipelines are vulnerable to corrosion, explained
Sankara Papavinasam, Ph.D., a research scientist with CANMET Materials
Technology Laboratory, Ontario, Canada, who helped to develop
ASTM Standard G 170.
Corrosion results, in part, from the use of carbon and low-alloy
steels in pipeline construction, which, although cost-effective,
characteristically exhibit poor corrosion resistance. The industrys
response has been to introduce corrosion inhibitors, primarily
in upstream pipelines carrying oil and gas from fields to processing
plants. The problem is that no single inhibitor suits all situations.
The effectiveness of an inhibitor is determined not only by the
properties of the gas and liquid contents of the pipeline and
by the properties of the inhibitor itself, but also by the means
by which it is added to the pipeline and by the operating conditions
of the system, such as temperature, flow rate and pressure. The
annual inhibitor market in North America alone is about $1.2 billion.
Selecting the appropriate inhibitor for a particular oil/gas
mixture and determining optimum use in the various delivery systems
are the key challenges facing the industry, he continued. In
selecting an appropriate inhibitor for a particular application,
several factors are considered, including the efficiency of inhibitor,
water/oil partitioning, solubility, emulsification tendency, foam
tendency, thermal stability, toxicity, and compatibility with
Papavinasam noted that the new ASTM standard describes three methodologies
that evaluate efficiency of inhibitors in the laboratory: rotating
cylinder electrode, rotating cage, and jet impingement. Compact,
inexpensive, hydrodynamically characterized, and scalable, they
can be carried out under various flow conditions. With these methodologies,
several variables that influence inhibitor performance in the
field can be simulated, including composition (of the steel, brine,
oil, and gas), temperature, pressure, and flow.
Also described in Standard G 170 are laboratory methods to evaluate
other inhibitor properties including water/oil partitioning, solubility,
emulsion, toxicity, foaming tendency, and thermal stability.
For workshop information, contact Sankara Papavinasam, Ph.D., CANMET Materials Technology Laboratory, Ontario, Canada
(phone: 613/947-3603), or Milan Bartos, Ph.D., Ondeo Nalco Energy Services, L.P., Sugarland, Texas (phone:
281/263-7985). To learn more about Committee G01, contact staff
manager Bruce Noe, ASTM (phone: 610/832-9719). //
Copyright 2001, ASTM