Liquid loading has been a problem in natural gas wells for several decades. With gas fields becoming mature and gas production rates dropping below the critical rate, deliquification becomes more and more critical for continuous productivity and profitability of gas wells. Current methods for solving liquid loading in the wellbore include plunger lift, velocity string, surfactant, foam, well cycling, pumps, compression, swabbing, and gas lift. All these methods are to optimize the lifting of liquid up to surface, which increases the operating cost, onshore, and offshore. However, the near-wellbore liquid loading is critical but not well understood. Through numerical reservoir simulation studies, effect of liquid loading on gas productivity and recovery has been quantified in two aspects: backup pressure and near-wellbore liquid blocking by considering variable reservoir permeability, reservoir pressure, formation thickness, liquid production rate, and geology. Based on the new knowledge, we have developed well completion methods for effective deliquifications. These lead to better field operations and increased ultimate gas recovery.

References

1.
Turner
,
R. G.
,
Hubbard
,
M. G.
, and
Dukler
,
A. E.
, 1969,
“Analysis of Prediction of Minimum Flow Rate for the Continuous Removal of Liquids from Gas Wells,”
J. Pet. Technol.
,
21
(
11
), pp.
1475
1482
.
2.
Dousi
,
N.
,
Veeken
,
C. A. M.
, and
Currie
,
P. K.
, 2005,
“Modeling the Gas-Well Liquid-Loading Process,”
Presented at the 2005 Offshore Europe
,
Aberdeen, United Kingdom
, Sept. 6–9, Paper No. SPE 95282.
3.
Coleman
,
S. B.
,
Clay
,
H. B.
,
McCurdy
,
D. G.
, and
Norris
,
L. H.
, III
, 1991,
“A New Look at Predicting Gas-well Load Up,”
J. Pet. Technol.
,
43
(
3
), pp.
329
333
.
4.
Nosseir
,
M. A.
,
Darwich
,
T. A.
,
Sayyouh
,
M. H.
, and
El Sallaly
,
M.
, 1997,
“A New Approach for Accurate Prediction of Loading in Gas Wells Under Different Flowing Conditions,”
Presented at the 1997 SPE Production Operations Symposium
,
Oklahoma City, Oklahoma
, Mar. 9–11, Paper SPE No. 37408.
5.
Gray
,
H. E.
, 1974,
“Vertical Flow Correlation in Gas Wells,”
User manual for API14B, Subsurface Controlled Safety Valve Sizing Computer Program.
6.
Bendisken
,
K. H.
,
Malnes
,
D.
,
Moe
,
R.
, and
Nuland
,
S.
, 1991,
“The Dynamic Two-Fluid Model OLGA: Theory and Application,”
SPE Prod. Eng.
,
6
(
2
), pp.
171
180
.
7.
Shoham
,
O.
, 2006,
Mechanistic Modeling of Gas-Liquid Two Phase Flow in Pipes
,
Society of Petroleum Engineers
,
Richardson, TX
, Chap. 4.
8.
Sagen
,
J.
,
Sira
,
T.
,
Ek
,
A.
,
Selberg
,
S.
,
Chaib
,
M.
, and
Eidsmoen
,
H.
, 2007,
“A Coupled Dynamic Reservoir and Pipeline Model—Development and Initial Experience,”
13th International Multiphase Conference on Multiphase Production Technology
,
Edinburgh
,
United Kingdom
, June 13–15.
9.
Bondurant
,
A. V.
,
Dotson
,
B. D.
, and
Oyewole
,
P. O.
, 2007,
“Getting the Last Gasp: Deliquification of Challenging Gas Wells,”
Presented at the 2007 International Petroleum Technology Conference
,
Dubai, UAE
, Dec. 4–6, Paper No. SPE 11651.
10.
Dunham
,
C.
,
Lea
,
J. F.
, and
Stephenson
,
G.
, 2008,
“Guidelines Help Operators Select Artificial Lift Systems for Deliquifying Gas Wells,”
American Oil and Gas Reporter
,
51
(
6
).
11.
Oyewole
,
T. O.
, and
Lea
,
J. F.
, 2008,
“Artificial-Lift Selection Strategy for the Life of a Gas Well With Some Liquid Production,”
Presented at the 2008 SPE Annual Technical Conference and Exhibition held in Denver
,
Colorado
, Sept. 21–24, Paper No. SPE 115950.
12.
Wang
,
Z.
,
Wang
,
X.
,
Li
,
S.
, Xu, Y., Zhang, J., and Lv, F., 2008,
“Experimental Study on Downhole Gas-Liquid Separation and Produced Water Reinjection,”
Presented at the SPE 2008 Annual Technical Conference and Exhibition held in Denver
,
Colorado
, Sept. 21–24, Paper No. SPE 115246.
13.
Lang
,
K.
, 2002,
“Options for Coalbed Methane Water Management,”
PTTC Network News, 1st Quarter
,
8
(
1
).
14.
Holditch
,
S. A.
, 1979,
“Factors Affecting Water Blocking and Gas Flow From Hydraulically Fractured Gas Wells
,”
SPE J.
,
31
(
12
), pp.
1515
1524
.
15.
Wang
,
Y.
,
Ehlig-Economides
,
C. A.
, and
Laine
,
R. E.
, 2006,
“π-Model Production Over Bottom Water,”
Presented at the First International Oil Conference and Exhibition in Cancun
,
Mexico
, 31 August–2 September, Paper No. SPE 102457.
16.
Gdanski
,
R.
,
Weaver
,
J.
,
Slabaugh
,
B.
,
Walters
,
H.
, and
Parker
,
M.
, 2005,
“Fracture Face Damage—It Matters,”
Presented at SPE European Formation Damage Conference
,
Sheveningnen
,
The Netherlands
, May 25–27, Paper No. SPE 94649.
You do not currently have access to this content.