KAZAKHSTAN UPSTREAM OIL AND GAS technology and R&d ...

As for the second challenge, most of the large
deposits of the Caspian Basin contain hydrogen
sulfide in the formation fluid. Distribution
of hydrogen sulfide is confined to specific
stratigraphic horizons, where a significant part
of the section is represented by carbonate rocks.
H2S being a permanent component of oil
and gas sub-salt deposits of the Caspian Sea
region, it has a highly detrimental effect not only
on the metals and grouting materials, but also
dramatically changes the properties of drilling
fluids.
Operation of drilling and oilfield equipment in
hydrogen sulfide deposits is complicated by
the corrosive phenomena. The most hazardous
form of corrosion is sulfide corrosion cracking
of ferrous metal equipment. The steels used
for oil and gas equipment must have special
properties, for example, ductility, resiliency,
chemical composition, and resistance to sulfide
corrosion cracking. Particularly vulnerable are
joint welds, where the metal has to be heat
treated in order to relieve stress and improve its
quality.
It should be noted that material selection is
important in reducing the chances of sulfide
corrosion cracking but that there are still issues
around other corrosion processes and hydrogeninduced
cracking of the metal. Therefore,
to ensure the availability of the necessary
equipment for the industry it is important, first of
all, to focus R&D efforts (in collaboration with
foreign R&D centres) to develop new types of
alloys and to produce them domestically by
2025. BOP equipment, boring casing, liners
and so forth of good quality are absolutely
essential in Kazakhstan.
As for the third challenge, one of the most
important issues in the course of well construction
is mounting (casing running, and cementing).
Poor-quality cementing of wells results in
significant costs and delays. The cement should
also have high corrosion resistance. Kazakhstan
does not produce such cements, but there are
factories in Russia that produce special cements
with the desired properties. It would make
sense to pursue the possibility of setting-up joint
ventures with such factories to address this issue
with the involvement of local research institutes.
As for the fourth challenge, the improvement
of drilling technologies in complex geological
conditions is a necessary condition for reducing
the cost of well construction in general. The
methods describe below are currently not widely
used in Kazakhstan, but could be with more
research and development.
Managed Pressure Drilling – managed
pressure drilling is when the flow from the well
is not specifically triggered during drilling, but
the pressure profile in the wellbore is precisely
controlled using enclosed and high pressure
drilling mud recirculation. Instead of relying
on a single mass of drilling mud, a managed
pressure drilling systems control the well pressure
by rotating the BOP head along with the ground
pressure equipment controlling the drilling mud
returning from the annulus.
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Kazakhstan Upstream oil & gas technology and R&D roadmap