Neftegaz.RU #3-17 ENG

PRODUCTION
TABLE 2. Restrictions of Water Inflow with Application of the MEGA Gel-Forming Compound at the SCT in the Area of Steam and Heat Effect
at the Permian-Carboniferous Deposit of the Usinskoye Field
Item No. Well number Treatment type Treatment date
Volume of ready-made
compound, m 3
1 7054 With SCT 06-07.10.2016 80
2 8126 With SCT 31.10-01.11.2016 80
3 6170 In the SHE area 14-16.11.2016 90
4 6108 In the SHE area 25-27.11.2016 85
5 4560 In the SHE area 10-12.12.2016 119
on the basis of the “aluminum salt –
cellulose ether – carbamide – water”
system with the following two gelforming
components: thermotropic
polymer solutions with the lower
critical dissolution temperature
based on cellulose ethers (“cellulose
ether-carbamide-water”) that
form gels due to the reversible
phase transition and thermotropic
inorganic “aluminum-carbamidewater
salt” solutions that form gels
by the hydroxo-polycondensation
reaction of aluminum ions [16].
They form coherently dispersed
nano-sized structures such as “a
gel in a gel”. When heated above
the lower critical temperature of
dissolving of cellulose ether in
the system, a polymer gel is first
formed by phase transition, and
then an aluminum hydroxide gel is
formed within the polymer gel by
the hydrolytic polycondensation
mechanism initiated by the products
of carbamide hydrolysis. The result
is improvement of structural and
mechanical gel properties and
multiple increase of its viscosity
and elasticity. Gels formed in the
reservoir restrain breakthrough
of water or steam from injections
to production wells, redistribute
filtration flows of reservoir fluids
in the oil reservoir, which leads to
stabilization or reduction of water
cut in production of surrounding
producing or steam cyclic wells, and
increase in oil production.
Combined nanostructured
gels obtained from the MEGA
thermotropic composition with
two gel forming agents, polymer
and inorganic, as well as cellulose
ether-based gels, will have better
adhesion to the carbonate reservoir
than aluminum hydroxide gels.
The composition is promising for
creation of anti-filtration barriers and
screens in oil reservoirs with the
aim of increasing oil recovery and
isolating of water inflows.
Field of application of the
technology are reservoirs with
the temperature of 60 – 220°С, in
particular, developed or introduced
into development by flooding or
steam and heat or steam and cyclic
effect. The type of collector is
terrigenous, polymictic or carbonate,
heterogeneous. The technology is
used in separate water injection,
steam injection, steam cycling and
production wells, in the group of
producing and injection wells, or is
carried out in general at the facility
or field.
First field tests of the MEGA gelforming
nanostructured compound
to limit water inflow and increase oil
recovery were carried out by OSK
LLC in late 2016 at the request of
LUKOIL-Usinskneftegaz of LUKOIL-
Komi at five production wells of the
Permian-Carboniferous Deposit of
the Usinskoye Field: two (No.7054
and No.8126) – with steam cycling
processing (SCP) and in three wells
(No. 6170, 6108 and 4560) – at
the site of steam and heat impact
(SHI), in the area of steam injection.
Treatment dates and volumes of the
compound are set forth in Table 2.
The volume of the injected
compound comprised 80 to 120
m 3 per each well, see Table 3. As
of the moment, first production
data after treatment of three wells
were received (see Table 4): for
well No.7054 – with SCT, for
wells No. 6170 and 6108 – in the
TABLE 3. Effect of Treatment of Production Wells at the MEGA Gel-Forming Compound at the STC and in the Area of Steam Heating
Effect at the Permian-Carboniferous Deposit of the Usinskoye Field
Before treatment
After treatment
Well number
Liquid
production rate,
m 3 /day
Oil production
rate, t/day
Wate cut, %
Liquid
production rate,
m 3 /day
Oil production
rate, t/day
Wate cut, %
7054 42.0 6.1 85.0 74.0 41.1 43.8
6170 55.9 0.8 98.6 41.6 6.0 85.6
6108 56.3 2.0 96.4 51.6 11.5 77.8
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