DECARBONIZING DRILLING
Companies zero in on cementing
process to have outsized impact
on well construction emissions
Solutions being deployed include well planning
and emissions monitoring software, as well as
technologies with reduced Portland cement
BY STEPHEN WHITFIELD, ASSOCIATE EDITOR
As the world continues to move toward a
low-carbon future, the oil and gas indus-
try’s ability, to not only reduce its emis-
sions but also to quantify its emissions
reduction performance, has become a pri-
ority. One component of the well construc-
tion process with significant potential for
emissions efficiency is cementing. Studies
have shown the production of cement to
be an emissions-intensive process involv-
ing heating kilns to very high tempera-
tures, as well as calcination, a chemical
reaction that occurs when raw materials
like limestone are exposed to those high
temperatures. Other steps like quarrying
and transport also add to the emissions
footprint. That’s why operators like BP are work-
ing on reducing their use of cement in
well construction, while cementing solu-
tions providers target reducing the car-
bon footprint of cement production, said
Emmanuel Therond, BP Technical Advisor.
One part of BP’s work in this area is
its Well Design Optimizer software pro-
gram, launched last year. It’s a tool that
its engineers can use to estimate green-
house gas (GHG) emissions as they are
planning wells. Cementing is one of four
components that the software measures,
along with fuel usage, planned testing and
planned casing, Mr Therond explained in
at the 2023 IADC World Drilling Conference.
The software uses pre-established
emissions factors to obtain estimates of
CO 2 generation from various activities.
Emissions factors are representative val-
ues that attempt to relate the quantity of
36 a pollutant released into the atmosphere
with an activity associated with the
release of that pollutant. When multiplied
by activity indicators input by the drilling
engineer, the software can provide an esti-
mate of the CO 2 emissions that the given
activity will generate.
Mr Therond noted that the software
is not a tool for reporting or calculating
emissions; the estimates generated by the
software are only shared within BP and
with its third-party contractors. The goal,
rather, is to help personnel decide if any
actions can be taken through better well
planning to help reduce emissions.
“This is a tool for estimating emissions
so that drilling engineers can understand
what options they have to reduce emis-
sions without compromising the well’s
construction,” he said. “It might sound very
simplistic, but I think this is the first step,
so we can start understanding and acting
upon these numbers. Right now, we don’t
have the tools that allow us to have quality
conversations with the drilling engineers.”
One of the first projects where BP
deployed the Well Design Optimizer was
an offshore well drilled last year in the
Mediterranean Sea. The process began by
entering data related to:
rig type (drillship);
number of days planned to drill the well
(183);
estimated diesel consumption (31
tonnes/day);
the type of well testing (flaring);
the specific gravity of the gas flared dur-
ing testing (0.70);
duration of testing (1 day);
Reducing the use of carbon-intensive
Portland cement in well cementing op-
erations can help the industry to reduce
its overall emissions profile, said Patrick
Lynch, Regional Business Development
Lead – Low Carbon Ventures at Halli-
burton, at the IADC World Drilling Con-
ference in London on 21 June.
the production rate during well testing
(50,000 standard cu ft/day); and
the slurry densities for each hole section
in the well.
From these inputs, the software gener-
ated an emissions estimate for the well,
multiplying select variables by given
emissions factors for each variable. It esti-
mated that the well would generate nearly
24,000 tonnes of CO 2 over its lifetime, and
only 2% of that would come from cement
usage. Since that is within the 1-5% aver-
age range BP typically sees, it confirmed
no action was required to revise the well
plan and cement usage. If the estimates
had been abnormally high, however, the
operator could have taken early steps to
alter the design.
Reducing Portland cement
in completions
Halliburton is also working to help
operators reduce emissions from cement-
ing through its Verified Integrated Design
Application (VIDA) and Envana Catalyst
emissions monitoring software. VIDA is a
design modeling software that identifies
the risk mitigation factors within a well’s
design; it can also be paired with Envana
Catalyst to provide a comprehensive esti-
mate of the amount of CO 2 generated by
SEPTEMBER/OCTOBER 2023 • DRILLING CONTRACTOR