Drilling and Completion Technologies of Unconventional Gas ... - Herong Sinopec-EN.pdf · Drilling and Completion Technologies of Unconventional Gas in SINOPEC. ... Casing string

Zheng Herong

Drilling and Completion Technologies of

Unconventional Gas in SINOPEC

September 2012

Outline

Major Features of Unconventional Gas Play

Key Horizontal Drilling & Completion

Technologies

Technique Challenges

Up to July 2012, a total of 2,483 unconventional gas wells have been drilled in Sichuan basin and Ordos basin, China. 2,454 tight gas wells including153 horizontal wells 29 shale gas wells including 13 horizontal wells

Sichuan Basin terrestrial sediments 18 shale gas

wells，including 10 horizontals

Southern China Marine Sediments

11 shale gas wells，including 3

horizontals


Xinchang of Western Sichuan（U. Trassic Xuwu

Member ) Attained good oil/gas shows，4

Section/24.6 m, Total Hydrocarbon content：0.006-

47.57%

Yuanba of NE Sichuan（Jurassic

Ziliujing Fm.）

5 wells tested Daanzhai Member ,

yield rate of 4944-17904 mscf/d

Puling of SE Sichuan（Jurassic Ziliujing Fm.)

Production rate of 3884-4470 mscf/d attained in 2 wells of

Daanzhai Member. Decided as the first

commercial shale gas production area

Jiannan（ Jurassic Ziliujing Fm. ）

Jianye HF-1 tested Dongyue Member, yielded

rate of 434 mscf/d

Pengshui（L. Silurian） Pengye HF-1 L. Silurian

horizontal section (2263～2526.7 m）, a 12-stage

fracture yielded gas rate of 882 mscf/d

Huangping（L. Cambrian)

Huangye 1 well tested Niutitang Fm., yielded

418m3/d

Shale gas exploration progress in China


1. Main features of unconventional gas reservoirs of SINOPEC Sequences Marine、Transitional、Terrestrial

Geological time

Marine sequences in L. Paleozoic and earlier（Proterozoic、∈1、S1）

Marine-Terrestrial transitional sequences in U. Paleozoic（C、P)

Terrestrial in Mesozoic(T3、J1-2）

Thermal Maturity

Highly mature for marine sequences（Ro>2.5%）

Lower mature for terrestrial sequences（Ro<1.5%）

Preservation Paleozoic marine sequences experienced multiple stages of

tectonics, is heavily faulted and structured Mesozoic terrestrial sequences is less deformed, with better

preservation condition

Burial Paleozoic marine sequences deeply buried Mesozoic terrestrial sequences has shallower, more ideal depth

Surface condition

Simple topographic conditions in Eastern China Complicated features in Middle and Western China

Water supply Ample water supply in Eastern China Insufficient supply in Middle and Western China


（1） Marine, Transitional and Terrestrial Sequences


Ages of major American marine shale (mainly in U. Paleozoic)

Basin name Appalachia Fort Worth Palo Duro Black Warrior Acoma Michigan Illinois

Shale name Marcellus Ohio Barnett Bend Floyd/Neal Fayetteville Woodford Antrim New

Albany

Age Middle

Devonian Series

upper Devonion

seris

Lower

Carboniferous

Upper Carboniferos

Lower Carboniferos

Upper Carboniferos

Late Devonian

Devonian System

Devonian System

Ages of major China marine shale (mainly in L. Paleozoic)

Basin name sichuan The middle Yangtze Lower Yangtze Qiannan

depression

Shale name doushan niutitang longmaxi shuijingtuo longmaxi hetang longyuan niutitang

Age sinian system

Lower Cambrian

Series

Lower Silurian Series

Lower Cambrian

Series

Lower Cambrian

Series

Lower Cambrian Permian Lower

Cambrian

（2）Marine formations of older geologic age


（3）High thermal maturity（Ro>2.5%）

Barnett Shale Ro contour


Fort worth basin, burial history from an Eastland well Burial history of south Diandong area from Dingshan 1 well

（5）Complex structure and highly variable preservation conditions


（6）Great depth variation

Depth:1981-2591m Barnett shale gas

1000 1000

1000

2000

Depth:1000-5000m


（7）Complex surface conditions

3.2 million km2 of plain area in central U.S.

Hilly and mountainous topography in Southern China

达县南充

重庆内江成都

乐山

昭通六盘水贵阳

US “Shale gas factory” production mode

昆明

Topograpic feature ,south area of china


（8）Shortage of water supply in Western China


2. New requests for drilling & completion technologies

Steering technique to maintain accurate well trajectory

Requirement of optimized and efficient drilling against

greater well depth and complicated in-situ stress field

Improvement of multi-stage fracturing technique to enhance

well productivity

Requirement for more cost-effective drilling strategy due to

lower reserve abundance

Demand of more environmental-friendly drilling strategy due to

shortage of water supply and environment issues


Outline



Technologies


1. Characterization of geological engineering environment

2. Techniques for optimized and efficient horizontal drilling

3. Wellbore stability technique for shale

4. Technologies of LWD system

5. Drilling fluid for horizontal wells

6. Horizontal well cementing in shale

7. Horizontal well completion

Key Horizontal Drilling & Completion Technologies

（1）For well design, distribution of shale, stress, content of gas and brittle

mineral shall be obtained based on seismic, logging and lab data.

Brittleness Evaluation with 3D Seismic Data

1. Characterization of geological engineering environment


(2) Continuous coring technologies in shale interval enables the calibration of

anisotropy description and geological parameters for terrestrial shales.

The core pictures of shale in well L69, SINOPEC


（3） Physical and mechanical parameters database of shale was established

based on analyses of mineral composition, microstructure and rock

mechanic parameters.

Shale mineral analysis Shale strength VS. mineral component

Shale component diagram


129.03 134.82

105.13

55.29 54.39

0

20

40

60

80

100

120

140

160

2007 2008 2009 2010 2011

Drilling period (d)

Before After

2. Techniques for optimized and efficient horizontal well drilling

Well configuration optimization:

3 layers casing configuration

Trajectory design & accuracy control

LWD, MWD, Rotary Steerable

Drilling period reduced by 48%.

（1） On the basis of well configuration optimization, trajectory

design & accuracy control, the wells can be drilled efficiently.


（2）PDC bit footage and life are extended, through cutter layout and

hydraulic structure optimization, based on logging data and rock

mechanic parameters.

M1952C Bit Logging data analysis

Maximum footage up to 1400 m in horizontal interval


EM1616 Bit


（3）‘Well Factory’ improves D&C efficiency Avg. rig time of horizontal well was 52.3d in 2011, while Avg. rig time of cluster drilling is 47.7d; Avg. ROP was 7.34m/h in 2011, while ROP of cluster drilling is 8.28m/h.



（4） “Learning curve” promotes the speed of D&C.




（1）Establishment of shale stability and risk prediction models,

based on mechanics research of shale formation.

Collapse cycle analysis

geostress

geologic structure

formation strength

Stress-chemical coupling analysis

Drilling data analysis

Laboratory test Logging data analysis

Triaxial strength test

D&S test experiment

Strength weakening test

permeability test

Shale membrane efficiency

Anisotropism analysis Wellbore

stress analysis

Pore pressure near wellbore

wellbore diameter analysis Wellbore enlargement ratio


(2) Geostress analysis Building pore pressure prediction model for optimal design；

Exploring wellbore collapse forecasting techniques to improve well

spacing and wellbore trajectory design.


First spud ： Wellbore ：Φ444.5mm×86m Casing：Φ339.7mm×84m

Second spud： Wellbore：Φ311.15mm×2202m Casing：Φ244.5mm×2198m deviation：45°

First spud： Wellbore ：Φ444.5mm×86.16m Casing：Φ339.7mm×82.16m

Second spud： Wellbore：Φ311.15mm×893.78m Casing：Φ244.5mm×889.78m

Before optimization After optimization


Developed high-performance drilling fluid system for SINOPEC shale oil and gas

reservoirs

----paraffin oil-based drilling fluid

----diesel-based drilling fluid

----under-balance drilling with strong inhibition drilling fluid

----amine-based drilling fluid

（3) Optimized drilling fluid system


Spud sequence

M-HF1 Design mud

density （g/cm3）

M-HF1 Actually

mud density

（g/cm3）

collapse pressure （g/cm3）

M-HF2 Design mud

density （g/cm3）

M-HF2 Actually

mud density

（g/cm3） Second

spud 1.25-1.40 1.26-1.35 1.20-1.38 1.25-1.55 1.25-1.50


LWD measured gamma ray, resistivity and neutron porosity enables

real-time analysis of the rock characteristics and fluid properties, to

monitor the horizontal trajectory in the target formation.



In 3rd spud of well PYHF1, horizontal drilling achieved maximal daily footage of 270 m, average ROP of 10.26 m/h, and deviation between designed and actual bore hole trajectory is <1 m.



(1) Shale cutting recovery of over 90% has been achieved, by applying

polymerization amine drilling fluid with temperature resistance of 180 ℃,

under-balance, strong inhibition fluid system, and fluid application

technique.

Drill cuttings without adding polymerization amine

Drill cuttings with adding polymerization amine

5.Drilling fluid for horizontal wells


Application

Maximal well depth up to 4,718m

Longest horizontal interval to 1,698.7m

Drilling period reduced by 13.4%

Longest interval for individual bit up to 1,120.2m

ROP improved 25.3%

5.Drilling fluid for horizontal well


(2)Development of recyclable oil-based drilling fluid

Emulsifiers for Oil-based drilling fluids

5.Drilling fluid for horizontal well

Applications：used in 4 shale oil wells and 4

tight oil wells.

E.g. average wellbore expansion of 1.9% in

well Boye Ping1 and 2% in well Boye Ping 2.

Good plugging and leak-proof performance

Suitable for formation temperature up to 170 ℃


Oil-base drilling fluid recycling and reuse equipment

The recovery rate of oil-based drilling fluid for well Boye Ping 1 is 55%, and 60%

for well Boye Ping 2.

The oil content of cutting in well Boye Ping 2 was less than 3%, which meet

Chinese class-1 environmental emissions standards.

Oil-base drilling cuttings processing equipment

Cost and pollution reduction (successful application in 2

wells --- Boye Ping 1 and Boye Ping 2)

5、Drilling fluid for horizontal well



Horizontal well cementing

Tech

Optimization of

cementing scheme

Tough and elastic cement slurry

Flushing pad with high

efficiency of oil removing

Liner tieback cementing


6. Horizontal well cementing in shale （1）Optimization of cementing scheme Optimization of cement slurry with excellent elasticity and

toughness Optimization of pad fluid with better oil displacing ability Cementing simulation and remote

transmission Simulation of optimized cementing

design Casing string centralization

Optimized design of centralizers


（2）Tough and elastic cement slurry

Characteristics high bond performance, high toughness, strong resistance to external impact

Effect analysis toughness coefficient improved by 90%, elastic modulus reduced by 55%



（3）Water flooding and flushing pad fluids Characteristics

Improved flushing effect and enhanced the

cementing quality

Effect analysis oil base mud removal efficiency --- 81.2%

mud cake removal rate --- 59%


Cementing slurry

Pilot slurry Spacer fluid Flusing fluid casing


（4）Liner tieback cementing

Reduced single stage sealing length

Liner hanger Pressure: 70MPa

Casing centrality in horizontal section:＞60%

Casing centrality in deviated section: ＞67%



Main completion techniques

Drillable bridging plug

staged fracturing well

completion

Hydraulic jetting staged fracturing well

completion

Preset sliding sleeve staged fracturing well

completion

Open hole packer +

sliding sleeve staged

fracturing well

completion



（1）Open hole packer + sliding sleeve staged fracturing well completion

Tools: open hole packer, pitch sliding sleeve, pressure sliding sleeve

Standard : 4 1/2″, 3 1/2″

Heat-pressure resistance: 70MPa, 150℃

Stage number: 20

Applications: 100% successful rate and effective rate



（2）Hydraulic jetting staged fracturing well completion

Tool types(4 1/2″, 5″, 5 1/2″, 7″), maximal 10 stage fracturing, applicable to casing hole, open hole or sieve tube well completion



（3）Drillable bridging plug staged fracturing well completion

Drillable bridging plug-perforation in staged fracturing well completion Application limit 70MPa and 150℃, 100% success rate.

Drillable bridging plug



（4）Preset sliding sleeve staged fracturing well completion

Maximal switch of preset sliding sleeve :＞50

No impact on well cementing

Maximal stage number of sliding sleeve：no limit

Preset sliding sleeve



Outline



Technologies


1. Identification and evaluation of shale oil/gas

reservoirs with logging technology Challenges Quantitative evaluation of reservoir parameters, fluid types and mechanical properties of shale

Development of relevant logging instruments


2. Geophysical prediction and hydraulic fracture monitoring of shale

Map view of microseismic results

Brittleness Evaluation with 3D Seismic Data

Prediction of shale distribution, shale stress, content of gas and brittle mineral content based on seismic data

Research on microseismic technology for hydraulic fracture monitoring

Challenges


3.Drilling and completion techniques

——Optimized and efficient drilling technique for horizontal well

—— Wellbore stability control technique

—— Technique of borehole trajectory control in long lateral

—— LWD interpretation and evaluation

—— Completion and cementation of horizontal well

Challenges


——Measurement of shale

mechanical properties

——MWD /Rotary steerable drilling

——Sealed coring

——Elemental logging

——NMR logging

4.Manufacturing of equipment and corollary instruments

Challenges


5. Environmental assessment

SINOPEC Working Site in Guizhou Province

-----Environmental risk assessment and environmental management -----Establishment of measures for environmental protection and soil and water conservation

Challenges


6. Integrated design

Integrated design of reservoir geology, drilling,

fracturing completion, flowback and production.

Unconventional well

Reservoir geological

design

Conventional well

Drilling geological

design

Drilling engineering

design

Completion/ production

design

Fracturing completion

design

Drilling geological

design

Reservoir geological

design Drilling

engineering design

Flowback/ production

design


Challenges

Cost reduction through unified organization, supply and

operation based on ‘Well Factory’ method.

7. Cost effective Strategy

Challenges


Thank you for your attention!

Documents

Drilling and Completion Technologies of Unconventional Gas ... - Herong Sinopec-EN.pdf · Drilling and Completion Technologies of Unconventional Gas in SINOPEC. ... Casing string