The XV International Forum-Contest of Students and Young Researchers

1.

The XV International Forum-Contest
of Students and Young Researchers.
TOPICAL ISSUES OF RATIONAL USE
OF NATURAL RESOURCES
Ogai Vladislav
RESEARCH STAND FOR
SIMULATION OF GAS-LIQUID FLOWS
Scientific adviser:
Yushkov Anton, PhD
Industrial University
of Tyumen
+7 922 004 0842
[email protected]

2.

OIL AND GAS PRODUCTION IN TYUMEN REGION
• The Tyumen region accounts for 64% of the Russian oil production and
91% of the Russian gas production.
• The map shows the fields of natural gas and gas condensates, which have
the problem of fluid accumulation in wells.
Moscow
Tyumen Area
Tyumen Region
Figure 1.Geography of the Russian market of the product
2

3.

STUDY PROBLEM
The problem of liquid accumulation inside gas and gas condensate wells occurs at a low
velocity flow of the gas-liquid mixture in the Production tubing. It should be noted that the
problem occurs in almost all wells completed as high-permeability and low permeability
reservoirs [1,2].
Vt – critical velocity to lift a liquid, m/s; σ – surface tension, n/m; ρl – liquid density, kg/m3; ρg – gas density, kg/m3.
1
14o
39
15o
39 ата
2
11o
39
3
8o
39
4
7o
39
5
7o
39
6
тыс.м3/сут
42
45
40
41
41.5
41
42
48
53
44
43
44
45
50
50
43
48
53
47
45
50
48
50
50
51
50
44
100 м
44.5
45
50
46
49
51
52
51
Figure 2. Liquid loading process by decreasing gas rate
3
52
48
54
52

4.

PARTICULAR OF PROBLEM IN RUSSIA
• The accumulation of liquid at the bottom hole of the well leads to a decrease in the
flow rate of the well and to its subsequent well shutdown - "self-kill" a column of liquid.
If in due time not to removal the accumulated liquid, then there are negative
consequences:
-he return filtration of borehole liquid in productive layer leads to deterioration in its
collection properties;
-washing away of layer collector leads to the increased sand production, formation of
sand-clay plugs.
• In recent years about 80% of natural gas is extracted from Cenomanian gas deposits
in Russia. Collectors for gas are sandstones and siltstones in varying degrees clay.
Considerable part of the Cenomanian gas deposits are in the later phase of
development, which leads to the manifestation of the described problems.[3, 4].
• Physical parameters characteristic of Cenomanian gas wells at the final stage of
development have specific features such as relatively low liquid content in the flow
(WGR<10−5 ), low formation pressure (up to 4 MPa), large diameters of production
string (114 mm и 168mm).
4

5.

RELEVANCE OF THE PROBLEM
• For 2015 at the largest gas operator of the Russian Federation, PJSC Gazprom, on
fields which provide 50% of gas production of the company more than 20% of fund
make problem wells, every year their number increases [5].
• For example, at the Yamburg field 344 wells are operated in the "self-kill" mode, at
Medvezhye 198, according to forecasts of by 2030 on the Urengoy field there will be
about 500 wells working in the “self-kill” mode [6,11].
• Large residual reserves of Cenomanian gas field of depleted field increase the level of
relevance of the issue (table 1)
Table 1. Residual reserves of Cenomanian gas field
5
Field
Enhanced gas
recovery in 2015,%
Remaining
reserves in 2015,mlrd.m3
Medvezhye
80,7
448
Urengoy
79,6
1094
Yamburg
79,1
815

6.

INJECT FOAMING SURFACTANTS
• The technology of introducing foaming surfactants into the well is widespread in the world, which
is characterized by a relatively low level of capital investments and a high level of efficiency,
including economic efficiency [7, 8, 9,10]
• In the Russian Federation considerable experience of application surfactant (in most cases solid
soap) in various regions is accumulated: on fields of the North Caucasus, Krasnodar Krai, the
Orenburg region, Far North (Yamburg, Urengoy, Medvezhye, etc.) [11].
• One of the most effective ways to production conditioning of well operating in liquid loading
mode is to periodically or continuously inject liquid foaming surfactants into the well. In Russia,
the technology is gaining popularity.
Figure 3. Introduce a surfactant at bottom of tubing
6
Figure 4. Solid soap sticks

7.

INJECT FOAMING SURFACTANTS
The foaming surfactant reacts directly with the well fluid and the gas upflow to form a foam.
The foam formation reduce the density of the gas-liquid mixture and the surface tension
between liquid and gas. Thereby reducing the critical speed required to remove the liquid.
Vt – critical velocity to lift a liquid, m/s;
σ – surface tension, n/m;
ρl – liquid density, kg/m3;
ρg – gas density, kg/m3.
Before
After
Liqui
d
level
Figure 5. Liquid level changing after surfactant treatment
7

8.

EXAMPLE OF TEST TECHNOLOGY IN THE FIELD «M»
• For unloading condensation water the technology of injection of liquid surfactant was tested
in three Cenomanian wells of the field "M" in the winter 2015-2016
• Pneumatic pumping units (figure 6) were used for injection of foam additives for constant
dosed supply into wells.
• Works on surfactant testing were carried out in several stages:
• Stage I - impact treatment of surfactant wells (40-60 liters), exposure to the response time,
work wells (gas production) to well flare stack to remove the accumulated liquid and sand
from the bottom hole of the wells.
• Stage II - work wells (gas production) to the gas gathering line with a constant dosed
supply of liquid surfactant in the annular space was (18-20 l/day. surfactant solution at 200250 l/day. waters)
8
Figure 6. Pneumatic pumping units

9.

EXAMPLE OF TEST TECHNOLOGIES IN THE FIELD «M»
The calculated flow rate without the use of surfactants for the removal of liquid from the bottom
hole of wells with a production tubing with a diameter of 168 mm and bottom-hole pressures
varying within 0.7-1.2 MPa is from 94 to 101 thousand m3/day. The use of surfactants reduced the
critical flow rate to 50-60 thousand m3/day. As a result of the application of the technology in the
wells decreased sand ingress, increased well flow rate to 90 – 100 thousand m3/day without
restrictions on the removal of mechanical impurities, the average increase in the operating flow
rate was about 40 thousand m3/day.
9
Figure 7.Field data after use surfactant

10.

THE LACK OF MODELS OF MULTI-PHASE FOAM FLOW
• In hydrodynamic simulation of gas field exploitation, the problem is the lack
of multiparameter models (functional relations) describing the multi-phase
foamed flow in gas well with surfactants. These models represent
multidimensional arrays (VFP-tables) and characterize drop pressures
between the bottom and the top of well.
• In Russia, the stands for research of multi-phase flow are not adapted for
qualitative studies of foaming flow.
• The few computational models obtained by foreign groups have drawbacks
and require adaptation at the fields in the Russian Federation, including for
the developed Cenomanian fields, due to specific conditions of
development (low liquid content in the flow, low formation pressure, large
diameters of production tubing, etc.).
10

11.

PREDICTION MODELS BY TNO, DUT & TU.
USED CLOSURE RELATIONS [12]
By TNO
Film liquid content:
with
By DUT
Film liquid content:
Film liquid content:
Lubrication layer:
Foam holdup:
Film viscosity:
with
By TU
Total liquid holdup:
with
Interfacial friction:
Film viscosity:
Interfacial friction:
Interfacial friction:
with
Γf – mean film quality
Гf,max – maximum foam quality
f – film thickness
D – pipe diameter
K1 to K8 – general constants
C – surfactant concentration
C* – surfactant specific concentration
, , 0 – modelling variables
Resg – gas phase superficial Reynolds number
11
fs – surfactant specific scaling factor for the
surfactant concentration
E1 to Е5 – constants
Usg – shear breaking down the foam
UTurner – estimate of the critical velocity using the
Turner relation
lub – lubrication layer thickness
l, g, foam – liquid, gas and foam densities
– surface tension
CD – drag coefficient of a sphere
G1 to G10 – constants
Usl – superficial liquid velocity
- – unloading potential

12.

PREDICTION MODELS COMPARISON VERSUS EXPERIMENTS
Case 1
Input: D = 50 mm, Usl = 10 mm/s, l =1000 kg/m3,
l = 1∙10-3 Pas, g = 1.2 kg/m3, and g = 1.8∙10-5 Pas
The anionic surfactant (TU) at 1000 wppm
The surfactant ‘Trifoam’ (DUT) at 3000 wppm
The surfactant ‘Foamatron’ (TNO) at 2000 wppm
Concentration scaling factors: fs.anionic =3fs.Trifoam fs,Foamatron=1,5fs,Trifoam
• The models of TNO and DUT agree reasonably well
with the experimental data for ~5 m/s < Usg < ~25 m/s.
• The deviation of the model of TU with the experimental
data is significant for the pressure gradient.
• The deviation for the model of TU is small for the liquid
holdup.
Case 2
Input: D = 100 mm, Usl = 10 mm/s, l = 1000 kg/m3,
l = 1∙10-3 Pas, g = 1.2 kg/m3, and g = 1.8∙10-5 Pas
The anionic surfactant (TU) at 1000 wppm
The surfactant ‘Trifoam’ (DUT) at 3000 wppm
The surfactant ‘Foamatron’ (TNO) at 2000 wppm
The concentration scaling does not seem to hold here.
Figure 8. ptot (a) and αl (b) as a function of Usg for an air/water/foam flow in a D = 50 mm pipe
• All models have more difficulty in predicting
the flow in the D = 100 mm pipe.
• The models of DUT and TNO seem to
deviate least from the experimental data for
the pressure gradient, while the results with
the model of TU are closest to the
experimental data for the liquid holdup.
• The results with the models of TU and TNO
are similar in shape, but differ by a factor of
about 1,5.
12
Figure 9. ptot (a) and αl (b) as a function of Usg for an air/water/foam flow in a D = 100 mm pipe.

13. RESEARCH STAND OF INDUSTRIAL UNIVERSITY OF TYUMEN

It is possible to conduct the experiments related
to the dynamic processes occurring in a gas
well, working with liquids (with surfactants and
other non-aggressive chemicals), and to obtain
digital data using the installation.
Figure 10. Photo and 3D installation
13

14.

TECHNICAL SPECIFICATIONS OF RESEARCH STAND
Table 2. Technical specifications
Specification
Tubing length (base)*
Unit
m
Value
6
Outer / inner diameter of tubing (base)*
mm
50/42
Working pressure in the system (not more than)
MPa
1.5
Working range of temperature
15…50
Max superficial gas velocity at pressure 1.5 MPa **
°C
m/s
Volume flow of water
l/h
3…1200
Volume flow of surfactant solution
l/h
3…1200
Absolute error of pressure sensors
Absolute error of water and surfactant solution
flowmeter
Absolute error of gas flowmeter
kPa
0.8
l/h
0.01
m3/h
0.1
Working fluid
Water, air (distilled water and brine)
*It is possible to change the diameter of the tubing and the tubing length.
**For the base diameter of tubing
14
10

15.

INSTRUMENTATION AND CONTROLS
Advantages of the software:
- process management
system;
- parameter control;
- error diagnosis;
-
data output;
- safety precautions at
workplace;
-
video recording of the
experiments.
15
Figure 20. Operation panel

16.

CONNECTION BETWEEN TU BAF AND IUT
Figure 21. Foam Analysis Instruments TU BAF
It is planned conducting experiments on the stability and destruction of the foam, depending
on the demulsifiers and the thermobaric conditions.
16

17. COMPARISON WITH WORLD ANALOGUES

Standard of comparison
Pressure and temperature
control
Ensuring the inclination
angle of tubing
Opportunity to study a
surfactant
Automatic maintenance of
WRG
Video recording of stream
17
Research stand of
GAZPROM “VNIIGAS”
Research stand of
Technische Universiteit
Delft
Research stand of
University of Tulsa
Research stand of
Industrial University of
Tyumen

18.

GW-SMART
GW-SMART - the system is the element of “smart deposit” and meant for optimization
of gas wells working in liquid accumulation regime. Removal of liquid is made by welltimed and dosed injection of foaming agent in a well. Analyzing data coming from
transducers and exposure to down hole equipment, the system allows you to identify
the characteristics of well performance (including: liquid rate, stored height of water)
predict its working regime with foaming agent, foaming agent injection guarantees
standard conditions of well performance (e.g. maximize gas production rate and
minimize foaming agent delivery). Two patent applications have been filed for the
technology.
Table 3. Equipment latching
Equipment latching
Figure 22. scheme of collection of information
18
1
Pressure sensor in inner annulus
2
Pressure and temperature sensor in well spring
3
Foaming agent supply module (reservoir for foaming
agent, foaming agent delivery pump, rate-of-flow meter)
4
Gas production rate regulator
5
Pressure and temperature sensor after gas production
rate regulator
6
Industrial controller, mini PC + Software
7
Foaming agent delivery line

19. ECONOMIC EFFECT FROM THE ADAPTATION

Table 4. Economic performance
Client profit:
Expenditure, mln. RUB.
Income, mln. RUB. (10 % per year decline
additional gas production)
СF, mln. RUB.
DCF, mln. RUB.
NPV, mln. RUB.
CAPEX, mln. RUB.
PI
0
6,50
1
2
3
1,66 1,66 1,66
4
1.66
7,37
6,60 6,00 5,40
4,80
0,87 4,94 4,34 3,74 3,14
0,87 4,45 3,52 2,72 2,06
0,87 5,32 8,84 11,56 13,62
4,84
2,81
Table 5. Cost structure
The cost for client:
Equipment*
Amortization
Installation works (including
transportation of equipment)
Surfactant investments
Electricity costs
The cost of the license of
the software "GW-Smart»
Total
Costs in the first year,
RUB.
2 600 000
260 000
Annual costs,
RUB.
260 000
1 440 000
-
1 100 000
300 000
1 100 000
300 000
800 000
-
6 500 000
1 660 000
* In the example it is assumed procurement: a) a surfactant supply unit (capacity for foam, a pump , supply line, flow meter, flow); b) control
flow rate of gas; c) pressure sensor and temperature gauge; d)industrial PC, etc) via radio. The volume of additional gas production was
estimated taking into account the results of the use of liquid foaming agents at wells 602, 622, 805 of Bear NGKM in the winter of 2016,
where foaming agents were used to remove the condensation liquid.
19

20.

REFERENCE
1) James Lea, Henry Nickens, Michael Wells. Gas well deliquification solutions to gas well liquid loading problems./ Gulf
Professional Publishing 2003. – 314.
2) Lea, J. F., & Nickens, H. V. (2004). Solving Gas-Well Liquid-Loading Problems. Journal of Petroleum Technology, 56 (04),
30–36.
3) Technology of production of low-pressure cenomanian gas/ Sarancha A.V., Sarancha I.S., Mitrofanov D.A., Ovezova
S.M.//Modern problems of science and education-2015-№1 (1). – 211.
4) Operation of gas wells in conditions of active water and sand production/ D.V Izyumchenko, E.V Mandrik, S.A
Melnikov,A.A Ploskov,V.V. Moiseev, A.N Haritonov, S.G Pamuzhak // Vesti gazovoy nauki.-2018.- № 1 (33). 235–241.
5) Results of the implementation of Сomprehensive program on the reconstruction and technical re-equipment of gas
recovery facilities for 2011–2015/V.Z Minlikaev,A.V Kovalenko,N.A Bilalov,A.V Elistratov // Gas Industry.-2017.- № 1 (747).
30–34.
6) Main causes of stopping gas wells at the final stage of development of deposits / Panikarovskii E. V., Panikarovskii V. V. //
The journal “Oil and Gas Studies” № 3, 2017: 85–89.
7) Kalwar, S. A., Awan, A. Q., Rehman, A. U., & Abbasi, H. S. (2017). Production Optimization of High Temperature Liquid
Hold Up Gas Well Using Capillary Surfactant Injection. SPE Middle East Oil & Gas Show and Conference.
8) O. Rauf, "Gas Well Deliquification–A Brief Comparison between Foam Squeeze and Foam Batch Approach," Journal of
Industrial and Intelligent Information, Vol. 3, No. 1, 45–47, March 2015.
9) Sean H. Peyton, Shona L. Neve, C. Krevor, (2013). Investigation of Batch Foamer Efficacy and Optimisation in North Sea
Gas Condensate Wells. SPE Candidate Paper.
10) Schinagl, W., Caskie, M., Green, S. R., Docherty, M., & Hodds, A. C. (2007). Most Successful Batch Application of
Surfactant in North Sea Gas Wells. Offshore Europe.
11) A.YU Koryakin, Complex solutions of problems of development and operation of wells of the Urengoy producing
complex- М., 2016 – 272.
12) Van ’t Westende, J. M. C., Henkes, R. A. W. M., Ajani, A., & Kelkar, M. (2017). The use of surfactants for gas well
deliquification: a comparison of research projects and developed models. BHR Group.
20

21.

The XV International Forum-Contest
of Students and Young Researchers.
TOPICAL ISSUES OF RATIONAL USE
OF NATURAL RESOURCES
Ogai Vladislav
RESEARCH STAND FOR
SIMULATION OF GAS-LIQUID FLOWS
Scientific adviser:
Yushkov Anton, PhD
Industrial University
of Tyumen
+7 922 004 0842
[email protected]

22.

RESEARCH AND TECHNOLOGICAL GROUNDWORK
• The publication of the article "Research of the foaming agents' influence on the process
of reservoir fluids and condensate recovery from Cenomanian gas wells on a closing
stage of development," in Proceedings of International Academic Conference "The state,
trends and problems of development of the oil and gas potential of Western Siberia"
(Scopus, 2018 ). Publication of an article in the journal Oil. Gas. Novations № 12/2017
"Study of the influence of foaming agents on the process of removal of formation and
condensation fluid from Cenomanian wells at a late stage of development" (VAK);
• The project attracted more than 5 million state grant funding;
• Meeting successfully carried out with Ltd NOVATEK Scientific and Technical Center, Ltd
Tyumen Oil Scientific Center and JSC Sibneftegaz ( PJSC Rosneft);
• The results are presented at the Colloquium of young scientists ("Russian-German raw
materials conference – 2018", Potsdam);
• Certificate for state registration of computer programs № 2018615013;
• RF patent for the invention № 2654889.
22

23.

PARTS OF RESEARCH STAND
в
Figure 11. Compression and surge
receiver
23
Figure 12. Water tanks and separators
Figure 13. Containers for
recycling

24.

PARTS OF RESEARCH STAND
Figure 14. Lower part of the
tubing
24
Figure 15. Upper part of the tubing
Figure 16. Sampling device
and heat-exchanging
apparatus

25.

PARTS OF RESEARCH STAND
Figure 17.
Bottom hole
25
Figure 18. Reverse flow video recording
Figure 19. Foam suppression system

26.

ANALYSIS OF WELLS WITH LIQUID LOADING,
MEDVEZHYE FIELD IN 2015
Reason of liquid loading
Periodicity blowing of gas wells
1 день
11
2
2
3
16
16
2 дня
9
11
3-5 дней
32
34
134
20
6-10 дней
11-15 дней
более 15 дней
Time of blowing gas wells
1
Numbers of wells different diameter
60 мин.
10
22
90 мин.
59
3
7
120 мин.
180 мин.
26
3
79

27.

ADVANTAGES
Criteria
Replacement of
tubing
CLC
PAW injection
RGM-Oil-GasService, National
NEF Pennant,
ZEDiInc.
Synergy-Leader,
Halliburton
-
+
-
-
-
-
+
+
5-8
0
8-10
0,18
1-2,5
0,5-2,5
4,3
1,2
9,3
13,1
10,9
14,2
«GW-Smart
OilWell Varco
Automation and control of the
technological process
Adaptation to change and quick
response
Capital investments, mln. Rub.
Operat. costs million rubles / year
Additional gas production million
m³ / year
• Digitalization of well operation, rapid adaptation to changes and fast response of
the system
• According to preliminary estimates, a 30% increase in additional production (7.4
million rubles / year * well, cost recovery in the first year) and a reduction in
surfactant costs by 25%
• Capital investments are 2 times less than competing technologies
• The ability to simultaneously manage tens / hundreds of wells
• Limitations: gas-liquid factor more than 0.17 m³ / l, electrification, the content of
condensate in the fluid is less than 50%

28.

RESEARCH STAND FOR SIMULATION OF GAS-LIQUID FLOWS & GW-SMART.
GW-SMART
Based on the data obtained from well research (or taken earlier or before technology
introduction) in Software computation model are inserted parameters: Тform –
formation temperature; Рform – formation pressure in a well; Нwell – well depth up
to bottom; НTBG – bottom depth of TBG; dTBG – inside diameter of TBG; dcs –
inner diameter of capital string or filter; hг – effective gas height; a0well и b0well –
gas flow coefficients; Mw.form – formation water salinity, Н1перф и Н2перф - depth of
top elevation and bottom elevation perforation interval or filter in productive
formation, etc.
Measuring equipment provides continuous parameters' monitoring: Тbuf, Рbuf –
temperature, pressure in well spring; Рann – pressure in inner annulus;
Тapron, Рapron – temperature, pressure after gas production rate regulator ( in gas
gathering tail); dr.regul. – drift diameter of gas production rate regulator and etc.
Software supplies engineering analysis in time; qc.form. – condensed fossil water
discharge; qg. – quantity of gas coming from reservoir ; hw – depth of watercut part
of perforated interval, CGR - gas-condensate factor, WGR - water – gas factor, etc.
Initial and calculated
parameters of the model