Progress of the EGS project at the Okuaizu...
Transcript of Progress of the EGS project at the Okuaizu...
Current status of the recharge experiment at
the Okuaizu geothermal field
November 20, 2019
T. Okabe, M. Kato, H. Nakata(GERD),Y. Abe(OAG), H. Asanuma(AIST),
M. Tsuzuki, K. Yoshimatsu(JOGMEC) andH. Kamenosono(JOGMEC, now KEPCO)
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Presentation
1. Project Overview1.1 Purpose and the schedule1.2 Project structure1.3 Okuaizu geothermal field
2. Present achievements2.1 Recharge Test in 2015 and its results2.2 Workover and recharge test in 2018
3. Summary
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1. Project Overview
• The purpose is to develop a guideline for an artificial water recharge technology and to develop a technical manual through a verification test and numerical simulation clarifying the impact of artificial water recharge on the geothermal reservoir and/or hot spring aquifer.
Research & Development FY2013 FY2014 FY2015 FY2016 FY2017 FY2018 FY2019
Project Planning, Design & Management
Geological/Geophysical Survey and Modeling
Design and Construction of Test Facilities (including wells)
Well Test and Logging
Operation of water injection
Numerical Reservoir Simulation
Monitoring
Preparation of Technical Operation Manual
If necessary
Modelling & Forecast Field data analysis & model upgrade
Background Operation
Injection was stopped due to interference with the nearest production well
Workover
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1.1 Purpose and the schedule
1.2 Project Structure
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JOGMEC
GERD OAG AIST
Tohoku Electric Power Co., Inc. (Yanaizu-Nishiyama Power Plant)
GERD
- Project Planning, Design & Management
- Survey and Modeling (MT)- Well Test and Logging- Numerical Reservoir Simulation- Monitoring (Downhole PT, Tracer test,
etc.)- Preparation of Technical Operation
Manual
- Project Planning, Design- Survey and Modeling (AMT ,
Gravity)- Monitoring (Seismic, Resistivity)- Preparation of Technical
Operation Manual
- Design and Construction of Test Facilities
- Operation of Recharge Test- Monitoring (Hot-spring
sampling )- Preparation of Technical
Manual - Local Coordination
Contract
Cooperation
JOGMEC : Japan Oil, Gas and Metals National Co.GERD : Geothermal Energy Research & Development Co., Ltd.OAG : Okuaizu Geothermal Co., Ltd. AIST : The National Institute of Advanced Industrial Science and Technology
Project leader
1.3 Okuaizu geothermal field
Tokyo
Fukushima
YanaizunishiyamaGeothermal Plant
Aizuwakamatsu
Turbine size was changed to 30MW on 28th August, 2017.
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24 years of operation in 2019
Actual
7" Slotted liner7" Slotted liner
9-5/8"CSGLiner hanger
8-1/2"2,225.00m
17-1/2" 1,005.00m
26" 155.00m
12-1/4" 1,880.00m
8-1/2"2,225.00m
17-1/2" 1,005.00m
26" 155.00m
12-1/4" 1,880.00m
Plan
20" CSG150.00m
20" CSG154.39m
13-3/8"CSG1,000.00m
ECP743m
13-3/8"CSG997.32m
5-1/2"TBG1,814m
9-5/8"CSG1,880.54m
1,840.48~2,100.26m
1,875.00m
2,225.00m
Casing program and a picture of the wellhead
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2. Present achievements
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【Term】1st : Jun. 4, 2015 ~ Aug. 31, 2015 (88 days)2nd : Nov. 27, 2015 ~ Dec. 26, 2015 (29 days)
【Recharge rate】
【Amount of recharge water】1st: approx.120,000 ton, 2nd : approx. 50,000 ton
1st 2ndMS Monitoring
Rech
arge
Rat
e
Steam increase, NCG decrease and easing of acidification were observed. Decrease of the steam rate and cyclic effect of the steam with the brine production was observed in late December at Well-8. The recharge operation was stopped on Dec. 26. This is because of thermal breakthrough from shallow LC zones caused by cementing problem of 9-5/8” casing.
2.1 Recharge test in 2015 and its results
Remove injection pipe
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01/4 02/4 03/4 04/4 05/4 06/4 07/4 08/4 09/4 10/4 11/4 12/4 13/4 14/4 15/4 16/4 17/4
Well-8
(涵養)
12/2
5/25
6/24
7/24
8/21
11/30
1/26
12/25
3/22
4/22
14JN-R1掘削
Well-8 production history
Well-8 NCG change
Recharge effect
Dilution by steam increase
30% steam increase
NCG decrease
NCG(wt%)
Stea
m ra
te(t
/h)
19t/h
14t/h
Recharge
Although effect by reservoir pressure increase while the maintenance increases the steam rate, recharge operation is conducive very much to increase Well-8 steam based on the tracer and NCG results.
Before the recharge : 8.9 wt%After the recharge : 5.0 wt%
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AE/Micro seismic array
NanometricsF: 20s~108HzVelocity@YAE1-5
アームロック機構
キー
ケーシング側
キー溝
IESE(NZ)Passive F: 15HzVelocity
Recharge point
YAE-7
YAE-8
YAE-9
2km
Existing station 5(OMS# :OAG)F: 4.5Hz,Fs=100Hz
+Surface station 5Borehole station 4
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OYO(ESG)F: 20~1kHz,Accelerometer
Nanometrics dataloggerRealtime observation by Fs=1000Hz
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0 500 m
Back ground
70 t/h
0 500 m
Recharge point
AE/Micro seismicity monitoring result
Back ground Step rate 50t/h 70t/h After injection(May) (Jun.) (Jun.-Jul.) (Jul.) (Aug.-Nov.)
Number of eventsper day 2.8 1.8 4.0 7.5 4.5
Local magnitude -0.53 -0.58 -0.38 -0.37 -0.59
Recharge stage
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Initial geothermal model was updated considering MS events.We reviewed:• Cap rock shape (② is not a cap rock) • Migration area and boundary of recharged water
(④&⑤ are very low permeability zone)
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②
④⑤
⑥ ⑧
⑩
⑦⑨
Updated ModelA A’Initial Model
Cap rock
Heat Source
Model improvement
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Temperature (deg.C)
ActualSimulation
Temperature profile
Temperature (deg.C)
Dept
h (m
)De
pth
(m)
A’
A
A A’
A A’Before
After
TOUGH2 simulation (Challenging)Natural state⇒History matching⇒Injection for superheated area
14The accuracy of the temperature simulation was improved.
26"坑 20"CSG 20"CSG 159.00m 150.00m 154.39m
ECP743m
17-1/2"坑 13-3/8"CSG 13-3/8"CSG 1002.00m 1,000.00m 997.32m
12-1/4"坑1560.00m ~1,610m
9-5/8"CSG12-1/4"坑 1880.54m
7"孔明管2100.26m
8-1/2"坑2100.26m
1890.00m
26"坑 20"CSG 20"CSG 159.00m 150.00m 154.39m
ECP743m
17-1/2"坑 13-3/8"CSG 13-3/8"CSG 1002.00m 1,000.00m 997.32m
12-1/4"坑1560.00m ~1,610m
9-5/8"CSG12-1/4"坑 1880.54m
7"孔明管2100.26m
8-1/2"坑2100.26m
1890.00m
26"坑 20"CSG 20"CSG 159.00m 150.00m 154.39m
ECP743m
17-1/2"坑 13-3/8"CSG 13-3/8"CSG 1002.00m 1,000.00m 997.32m
12-1/4"坑1560.00m ~1,610m
9-5/8"CSG12-1/4"坑 1880.54m
7"孔明管2100.26m
8-1/2"坑2100.26m
1890.00m
(1)Present (2)Side track (3)Metal packer+casing cement
Injection water L/C behind the casing
Side track
Plug back
Metal packer
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Slotted linerSlotted liner Slotted liner
2. 2 Workover and recharge test in 2018
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GoodA bit good
A bit goodMetal Packer
【Bonding】
Enlarged view
Metal Packer
Metal Packer deployment during cement curing
Result of the recharge test
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Existing Fault
Recharge Well
Well06
Steam increase (1.7t/h)
Steam increase (1.4t/h)
Production was suspended in advance to prevent interference caused by water injection : H30/11/22~12/18
Estimated Fault Target
During the workover, recharge test to check the present recharge situation for long term recharge operation in future was conducted for a month. Injection rate was 5t/h.
①In 2015 recharge tests, 170,000t water was successfully injected and a response to recharge (increase in steam flow) at Well-8 is observed and is estimated by approx. 30%.
Although further study is required about the recharge effect, production rate at wells close to the recharge well increased. In addition, non condensable gas(NCG) decreased at those wells as another benefit of the recharge operation.
Thermal break through at Well-8 was observed at the end of December 2015. From the observed Well- 8 steam stable behavior between Dec 5 and Dec 23, the slow decline of the steam at Well-6 and the decrease of the superheated amount together with the slow decline of the steam at Well-5, it is possible to maintain and/or increase of steam production by proper control of the recharge operation.
②In 2018 recharge tests, a response to recharge (increase in steam flow) at Well-3 and Well-6 isobserved and is estimated by 1.7t/h and 1.4t/h respectively.
③New geothermal model was created with new information from the latest technologies such as MT 3 dimensional analysis, PTS + sampler logging, high temperature PT monitoring, etc.
④The accuracy of the simulation was improved based on the geothermal model, and details such as (1)permeability of the formation , the range and boundary of fluid migration, (2) new faults, and (3) the relationship between the fracture and the fault were revealed.
3. Summary
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⑤A metal packer and cementing procedure was used to shut off the leakage at 7 ” casing shoe completely and it was deployed successfully . The metal packer was used for the first time in Japan.
⑥In 5-7/8 “ drilling, the main injection zone at about 2030m in the original well was captured at 2023m of the side track well as expected.
⑦Recharge test was started from July 2019 and is currently ongoing. An artificial recharge technology manual applicable to geothermal areas in Japan will be created with analyzing long-term recharge test data and establishing appropriate recharge injection design and management technology considering economic aspects.
Introduced cutting edge technologya. 3D MT analysisb. Recharge simulation for superheated reservoir (add supercritical option)c. New technology(combination of the focal mechanism analysis, scattering analysis,
migration method and accurate hypocenter determination) for flow path identification of injected water based on microseismic monitoring data
d. High temperature borehole PTS+fluid samplere. High temperature (300deg.C) downhole pressure/temperature measurementf. Installed high temperature downhole seismic toolsg. Installed a metal packer for the first time in Japan
3. Summary(Cont.)