Page 108 - Industrial Plants 2014

All our solutions are well explained by the case for months at a time, losing an average of around 20
history that follows. barrels per day. If a new liner could be installed, the
cost of repairing the damage was roughly $ 90,000.
If there was a dogleg in the well, however, it would
PXP improves oilfeld operation have to be idled and a new well would have to be
by optimizing steam injection drilled, for a total cost as high as $ 500,000. The
company was averaging 10 cut liners per year.
Thermal energy is commonly used in oil extraction to Furthermore, for each month each well was not
stimulate production. Thermal energy is also the producing because of a cut liner, an average of 600
greatest cost of oil production for many tertiary barrels of production
recovery projects. The heat injected in the form of was foregone. Manual monitoring
steam commonly accounts for 40 to 65% of a Manual monitoring methods were not the
producer’s costs and is responsible for much of the methods also led to most effective method
revenue derived from production of a well. On the under-injection, which to prevent over-
Hopkins lease property 35 miles north east of meant foregone injection of steam that
Bakersfield in California, there are close to 171 production. Part of caused breakthrough
producing wells. The wells are concentrated in a one the problem was lack and cut liners in
square mile area, producing approximately 3,200 of timely information. producing wells
barrels of oil per day. This field also has 120 steam With 120 wells to visit
injection wells, each of which heat and push oil the operators could,
at most, get one data point per well per day. The
data then had to be manually entered into a
database quickly and accurately. Even if the data
was accurately gathered and entered, the data
collection rate of once per day led to lag time in
responding to issues that impacted costs and
production.
Another part of the problem was the technology
itself. The accuracy of metering with an orifice and a
chart recorder was a concern. For one thing, PXP
was dependent on a contractor to provide the
proper coefficient for the orifice plate to get an
accurate flow reading. For another, they had to be
sure the orifice was installed properly and remained
intact. Finally, the charts had to be read accurately,
with the chart recorder properly calibrated (a task
done every three months) with no plugged tubing.

PXP wireless steam toward a pattern of producing wells. In order to meet Steam injection wells
injection well flow rate the production goal and optimize SOR (Steam to Oil PXP looked at wireless technology to provide real-
monitoring Ratio), it is critical to measure injected steam rate, time information to optimize steam injection rate.
total injected steam, and water and oil production to The mesh technology from Emerson combined with
optimize the effect of thermal stimulation on ProSoft Ethernet radios provided a robust, reliable
production. solution across the one square mile property. PXP
Because there was no power or communications in chose the Emerson wireless solution because of the
the vicinity of the wells, the field was monitored by security built into the network and the reliability of the
mechanical chart recorders and operator trips to as robust, self-organizing mesh that is easy to install
many wells as possible in a day. The daily readings and expand. The solution from Emerson opened a
by operators were summarized once a day. The data new pathway to capture realtime, accurate, and
was then sent to the office in Bakersfield where it nearly maintenance-free well test data.
was used to make business decisions. Manual The solution began with a pilot project to test the
monitoring methods were not the most effective technology on four injection wells. Ten 3051S
method to prevent over-injection of steam that WirelessHart™ pressure transmitters were
caused breakthrough and cut liners in producing purchased and installed; one on the upstream side
wells. Cut liners would take a well out of production of a fixed bean choke to calculate flow rate (upstream

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