Polymer is usually used in Enhance oil Recovery for improve sweep efficiency & mobility ratio is less than 1 , but here polymer used for profile modification in largest oil field in russia

1. Polymer Profile
ModificationRomashkino Field Russia
Muhammad Noman Khan
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nkmuhammad3@live.utm.my

2. 2

3. Romashkino Field
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 Field in Tatarstan Russia (Top ten Largest Field in the world) (SPE105199) & (SPE 36212)
 70 Km(44 miles)
 Structural Height of 50- 60 m(167-197)
 Reservoir Depth of 1600 -1800m (5200 to 5900ft)
 Devonian Sandstones & Carbonate Rocks
 K sandstone layers is 200 to 420mD.
 Por is 18.8% to 20.4%.
 So= 69.4% to 90.5%.
 TATOLPETRO Company to perform Polymer modification treatments of water injectors in
order to produce additional oil.
 Pi= 160 to 180 atm (16.2 to 18.2 Mpa).
 (1975)Total volume of fluid injected in the program reached
of the total extracted fluid.
1933
1947 & 48
1954
1958
1963 1975
Oil Field Review Russia 2000

4. 4L.L.LU ET AL. Scientific Research

5. 5L.L.LU ET AL. Scientific Research

6. 6IOR 1995

7. 7IOR 1995

8. 8
IOR 1995

9. Representation of Romashkino reservoir
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SPE 38464

10. 10L.L.LU ET AL. Scientific Research

11. 11

12. 12L.L.LU ET AL. Scientific Research

13. Reservoir Properties
• The 25° API crude
• Original formation pressure: 16.3 - 18.2 MPa;
• Saturation pressure: 8.5 - 9.5 MPa;
• Original gas-oil ratio: 40 - 65 m /t;
• Oil density: 0.858 g/cm ;
• Viscosity: 2.6 - 4.5 mPa.s;
• Wax content: 3.2%;
• Sulfur content: 1.3%;
• Tr= 37.8 Centigrade
• Original Water saturation : 17%- 21%, 19% in average;
• Proven reservoirs of field are 421.22 oil layers are established
• The D1 layer , the burial depth ranges from 1650 m to 1850 m.
• OOIP= 45 X 10 8 tons
• Large area, big formation dip , many oil layers, wide oil water
transition zone
• Complicated sedimentary environment
13L.L.LU ET AL. Scientific Research

14. Divison of Oilfield Development Stages
• We divide the Romashkino oil field development stages in to four stages
a. (1952- 1969) : increasing oil production stage
b. (1970-1975) : stable oil Production stage
c. (1976-1992) : oil Production decline stage
d. (Since 1993) : decline slowed down
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L.L.LU ET AL. Scientific Research
a
b
c
d

15. 15

16. 16
• Candidate Selection- selection of wells to be treated is
performed historical , available reservoir and production data
indicating low sweep efficiency
• Wells are gathered in clusters, individual injectivity is known
with difficulty
• Treatment Design- treatments generally consist in injection
per well of 20 tonnes of special HEC grade at the Conce: of
1% vol., representing 12000bbl.
• Collaboration b/w Total, Tatneft and Baker had designed the
Special mobile injection unit
• Treatments last from two to 10 days, before water injection is
resumed & after a one day shut-in period.

17. Case Histories
• Since 1992, by jan 1996, 134 injectors have been treated
with 2795 tonnes of the HHEC grade
• Offset producers number 498
• The additional oil amounts 4.6 millions bbl, efficiency of
235 tonnes of oil per tonne of polymer (1650 bbl/t)
• The Treated wells are located at 4 regions of
southeastern Romaskhino field
• End of 1992, 30 injectors were treated with 600 tonnes of
HEC; 4 year later, the incremental oil is 1.9 millions bbl ,
eff: of 450 tonnes of oil per tonnes of polymer( 3150 bbl
oil/t)
• Selected zone treated during first years of the project &
gave results
17
SPE 36212 & IOR 1995
SPE 36212

18. S-Romashkino Case
• Zone is formed of 12 IN treated b/w Sep 1992 and july 1993.
35 offset producers are submitted to the influence of these
water injection wells
• The perforated layers in these horizons are indicated in Table
1 & some injectivity data in table 2.
• The oil & water production ,WOR,and Cummulative oil (from
Jan 1989 to jan 1996) as shown in figures.
• To convert 1 tonnes in to bbl, one has to x the figures by 7 (25
API oil is 0.9 tonne per 1 m cube or 6.3 bbl), 1 tonne of salty
water will be estimated to 5 bbl(20% TDS)
• The HEC injection decrease of H20 production by a factor
about 2 (from 8300 bwpd to 5000 bwpd), together with an
increase of oil production by a factor about 3 (from 3000 bopd
to 1000 bopd), decrease water cut by 16 points from 96% -
83%.
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Changes in fluids prod in jan 94, after 6 to 16
months following the first and last injector
treatment, by jan 96 30 to 40 months later, the
treatments are still efficient , & come back to
base lines.
SPE 36212
FROM 2557 TONNES/TONNE FOR INJECTOR # 1723a to 1
tonne/tonne for # 1840a, about 3 years after the treatments the for S-
R 721000 bbl and 398 tonnes of oil per tonne of polymer (2780bbl/t)

19. • Injector 1933- the Inj well treated in sept 92, with 13000
bbl of HHEC at 5000mg/l
• Perforated at 5 layer 4 producer whivh are connected to
2, 3 or 4 of them.
• The evaluation for the 4 offset producers of the WOR as
function of cumulative oil, 17 months were needed
before decrease WOR, Jan 96 the efficiency of treatment
terminated.
• WOR evaluation before treatment ( about 10,000 tonnes)
• The eff: is 913 tonnes of oil per tonne of polymer (6400
bbl/t)
19
SPE 36212

20. • Producer # 1826d-the well influence of injector# 1723a, 6
producer
• The injector was treated in sep 92 with 18000bbl of HEC at
6000mg/l
• The 288600 bbl, eff: 2577tonnes of oil per tonnes of polymer
(18000bbl/t).
• Increased oil production 2 months following treatment & x by
factor 10 four mths later.
• The oil rate went from 2 bopd to 23 bopd, still constant 40
mths later
• The water went from 7 bwpd to less than 1 bwpd, water cut
switched from 80% before treatment to 5% since jan 94 until
now.
• Producer# 1719a- Jan 96 130850 bbl oil , eff: 1246 tonnes of
oil per tonnes of polymer (8700 bb/t)
• Oil Prod increased after 2 mths, 16bopd to 233bopd sixteen
mths later
• Water from 1500 to 1000 bwpd, from 99 to 81%
20SPE 36212

21. v
21
SPE 38464

22. 22
IOR 1995

23. Important aspects
• The HEC increase viscosity when dissolved in more
salty water
• When HEC injected it goes to high K. see figure ,
mechanism applied on additional oil obtained from
producer #1719a
• Water stopped it will go to low k layer, this mechanism
why produce in case of producer# 1826d
• By possible enhance of areal influence of other injectors
close to offset producers
• Direct increase of injection rates of untreated injectors
belonging to same cluster than treated one.
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24. Status of Romashkino field
• For conductance of geologic and hydrodynamic
modelling we have determined the main principles
• -structure by structure modelling of field
• -uniform procedure principles for all being modelled
structures
• -parallel modelling of main field elements-areas
• Based on modelling active development by;
• -drilling new wells, sidetracks, double wells, horizontal
wells
• -Improvement of WF sytems
• -Application of new methods on EOR & stimulation
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SPE 65190

25. 25
Russia Energy data base 2006
Current Status Of Romaskhino field

26. • Review of water-control chemical technology
• -cover board range of techniques
• -organic, inorganic polymer/gels, cements, resins, foams,
emulsion, particulates, emulsion, micro org,infill drilling,
pattern flow control horizontal wells
• -MC , the polymer needs to penetrates as far as to low K toto
ensure the eff: of oil displacement due to increased viscosity of
mobile agent , In PM , Polymer enters as less as to oil prod
zones in order not to reduce any wanted oil production due to
influx modif: of displacing agent(Water or gas)
• Organic polymers/ gels-can be naturally or synth: produced,
natural polymers are biopolymers(xanthane, scleroglucan,
curdlan, simusan, succinoglycan produced my micro organ:),
cellulose, lignins, guar gums or starch.
• Polymers can be used by own or as gels reaction with cross-
linkers
• The use of polymers alone for water control in producing wells
isessentially linked to relative k modification technology.
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27. • The formation of gel with polymer , cross linker leads to
increased mechanical , thermal stability, can control
gelation reaction
• Crosslinkers are organic( eg: Phenol-aldehyde)
inorganic( eg: metal ions)
• Introduce chelates with organic acids, which prevent
precipitation of metal NaOH, limit loss of reactive metal
through rock adsorption & delay the a reaction with
polymer through rupture of metal/ ligand bond with
temperatue.
• Cellulose drive; MC, CMC, HEC & CMHEC.
• Cellulose derivatives are reported to make gel with
metals or organic cross-linkers
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28. • HEC used in Romaskhino field , Mw is 1 million, give
higest viscosity of the HEC compounds
• This type of polymer is increased viscosity with salinity
• @ 100F, PH = 6.5, f, 20000cp in distilled water, 40000cp
with Nacl
• The power granuometery goes from 175 to 425 um with
around 60% in the 300 to 350 um range
• @ 100f , pH =6.5 & in 25% Nacl, 2 hrs are needed in bulk
to reach constant viscosity , this time doubles at pH =5.
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29. • The con: of HEC depends
• -salinity of water
• -T of water , formation
• -injectiviy of treated well
• -characteristics of the product
• Water in which Hec mixed;
• -formation water, waste water, river or lake waters.
• Very from well to another well,
• -tonnage of HEC per well: 20 tons(10-30)
• -duration of a treatment: 10 days(3-20)
• -average q: 300 cube metre per day (180 -720)
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30. Conclusion
• HEC as profile modif: in Romashkino b/c low T, very
saline, multi-layered, fractured sandstone reservoir,
exploited by water flooding for decades.
• Reaching high k zones, face plugging high conductivity
fractures, plugs the matrix rocks
• High eff: since 1992, 134 inj . 494 prod,
• Oil amounts 4.6 millions bbl with eff: 240 tonnes of oil per
tonne of polymer, the first well treated during first years
crossponding to best candaiate for such treatments &
gave significant higher eff:
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31. References
1. Loppinet, A., Iakovlev, S., & Glenat, P. (1997, January). Five years of injection of
hydroxyethylcellulose: An ecological pure product for enhanced oil recovery in the
field of Romashkino. In Offshore Europe. Society of Petroleum Engineers(38464)
2. Abdulmazitov, R. G., Blinov, A. F., Dikov, V. I., Ibatullin, R. R., Latifullin, F. M., &
Khisamov, R. S. (2000, January). Reservoir modeling for giant Romashkino field
(problems and solutions). In SPE European Petroleum Conference. Society of
Petroleum Engineers( 65190)
3. Lu, Liuli, Zhibin Liu, Haohan Liu, and Yongqin Yan. "Study on Technical Measures of
Romashkino Oil Field after Entering Ultra-High Water Cut Stage." Engineering 5, no.
07 (2013): 622.
4. Galeev, R. G., R. Kh Muslimov, R. N. Diyashev, and A. F. Blinov. "40 Years Experience
of Romashkino Oil Field Development in Tatarstan: Improvements of Water
Flooding." In IOR 1995-8th European Symposium on Improved Oil Recovery. 1995.
5. Glenat, P., Zaborowski, G., & Loppinet, A. (1996, January). Profile Modification in
Water Injection Wells by Polymer Treatments. In Abu Dhabi International Petroleum
Exhibition and Conference. Society of Petroleum Engineers.(36212)
6. Moussine, Kamil, Nail Gabdelbarievich Ibragimov, and Rais Khisamov. "The
optimization of the gas-steam injection using numerical simulation." In SPE Middle
East Oil and Gas Show and Conference. Society of Petroleum Engineers, (105199),
2007.
7. Seismicity in the oil Fiels, Report 2000, Schlumberger, VV Adushkin - 1976
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