Note: Descriptions are shown in the official language in which they were submitted.
I co
Closed-Loop Multilateral Thermal
0 Capture Method and System
CONCEPT, APPLICATIONS, ADD¨ON ENHANCEMENTS
Inventor: Dr. Michael J.L. Aikman, P.Eng.
0
TRINDADE RESERVOIR SERVICES INC.
Date Recue/Date Received 2020-11-25
ru
Motivation for Geothermal Energy:
Society is moving toward energy sources that have low (or no) greenhouse gas
emission
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Heat Production From Underground Formations
e Geothermal processes seek to produce heat from underground systems
to surface
0
.4g> "Clean Energy from Oil Reservoirs" also produces heat from underground
reservoir that is generating
heat from in-situ combustion (see applicant's patent application nos. US
63/059,605 and CA 3,088,665)
=_
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)' Industry's current well designs apply drilling technology that is
standard in the oil and gas industry
). Includes vertical wells, horizontal wells and horizontal wells with
fractures
1::
). Inherently limited for closed-loop geothermal energy: low working fluid
residence time, low overall well
surface area, low material conductivity (cement), high risk to execute the
well as designed, high cost
z
). A new method is needed that
reduces risk and cost without reducing residence time, surface area,
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thermal conductivity
TRINDADE RESERVOIR SERVICES INC.
2
=
Date Recue/Date Received 2020-11-25
Geothermal Electrical Generation: standard surface facilities.
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Wells types used to extract heat can significantly vary
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Date Recue/Date Received 2020-11-25
Geothermal engineering concepts:
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o Open loop system: exchanges mass and energy with Closed loop
system: no mass exchanged with the heat
heat reservoir reservoir,
only energy (shown is Eavor's closed loop system)
https://eavor.com/about/technology
TRINDADE RESERVOIR SERVICES INC.
4
Date Recue/Date Received 2020-11-25
Well Selection for Geothermal Energy
Open system wells allow direct production of the fluids in the pore space or
fracture network of the
thermal reservoir; many cases also have direct injection of water into the
pore space or fracture
co network
=_
Closed system wells do not exchange mass or fluids with the thermal reservoir:
the working fluid is
z confined to the wellbores; only energy is transferred into the
working fluid from the thermal reservoir
by heat conduction through the casing or tubing
0
z
There are limitations:
=_
Thermal gradient is about 25 C per km depth, so the wells must be drilled
very deep to access suitably high
temperature rock
)%. The available heat energy in the subsurface is usually limited ¨ once the
heat energy is removed from the formation,
heat conduction from the base and cap rock will not replenish the heat energy
removed (in reasonable time frames) ¨
the produced fluid thermal energy will decrease over time (as demonstrated by
lower wellhead temperature)
Closed loop systems need sufficient retention time for the circulation fluid
to heat
)=. Implies low flow rate or very long well length due to the relatively low
subsurface temperature (<200 C for geothermal
formations)
)%. Due to the large depth, even with insulation thermal energy is lost in the
vertical up-production string
0
)%. Restricted to regions that have high geo-temperatures which may be remote
and lack infrastructure
TRINDADE RESERVOIR SERVICES INC.
5
Date Recue/Date Received 2020-11-25
c. Favor closed loop system: description
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8 https://eavor.com/about/technology
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c > Closed loop system: wells
do not exchange mass or
a .
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z fluids with the
thermal reservoir
> Multilateral wells, drilled from two pads, and
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connected in the middle deep in the reservoir
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=¨
p _
4-1 ,
ul . Need many laterals
with extreme length to ensure
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, sufficient residence
time to heat the working fluid
a - -;\'-. ,=00 :
z ,......"00,
....._,..,,
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Eavor: Closed loop: closed loop well method
TRINDADE RESERVOIR SERVICES INC.
6
Date Recue/Date Received 2020-11-25
rt, Favor closed loop system: drilling sequence
https://eavor.com/about/technology
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Drill down vertically Continue drilling After connecting the
toes, Continue the process,
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horizontally and connect set a whipstock and
kick kicking off additional
the two wells at the off laterals from
the heel laterals from the heel area
0 "toes" of the wells of the original
wells; drill of each original wellbore
the two laterals toward
and connecting the toes of
each other and connect
each pair of laterals
TRINDADE RESERVOIR SERVICES INC.
7
Date Recue/Date Received 2020-11-25
ro
Eavor closed loop drilling description
Riser wellbore (vertical) drilled from surface to depths of up to 5 km
)= %. Well then drilled horizontal for lengths between 2 to 5 km in the
thermal reservoir
)%. A second well drilled from a site about 5 to 10 km distant, up to 5 km
vertical depth, then horizontal drilling for
between 2 to 5 km
)=. Objective is to intersect the first wellbore at the toe of the well
O )=. Uses radiomagnetic methods to steer the wells and to provide a target
for intersection
)%. To pick representative numbers: at 4 km depth and up to 7 km total
drilled length to the toe of each lateral, the
uncertainty of positioning is high, increasing the risk of non-intersection:
likely requires some amount of drilling
iteration to steer the second wellbore to hit the first
z )= %. Each successive branched multilateral drilling execution will
become ever more complex and risky due to
"underground clutter" of wellbores at the heel region:
)%. Additionally, there are two 90 degree turns and a sharp kick-off point
that will increase drilling risk
LLI
CI Risk of kicking off all the laterals from the heel of the well puts in
jeopardy the entire well, and risks losing the well
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Instead of branching from a small zone, how does one convert this process to
mostly linear drilling (reducing
curvature), and increase the size of the intersect target?
TRINDADE RESERVOIR SERVICES INC.
8
Date Recue/Date Received 2020-11-25
r. Motivation for Well Improvement:
E .t. 8
t >. Improve the closed loop well system used for geothermal energy production
.'
Potential Improvements: maximize heat transfer, reduce cost, reduce risk
> Increase surface area of the well system, increase the residence time of the
working
8
fluid
e
0
.4g > Increase the "size of the target" for underground intersection
42
> Reduce the number of turns in the well to improve drilling and completion
probability of
LC:3 success
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.= > Reduce the risk of the process of adding multilaterals by not
repeatedly "kicking off"
a'
r- additional laterals from the heel zone of the original horizontal
lateral
z
w
0
a:
z
o
0
TRINDADE RESERVOIR SERVICES INC.
9
Date Recue/Date Received 2020-11-25
New drilling method _ description
o = Drill and case a conventional single lateral well from surface:
one 90 degree turn to form a horizontal trunkline in the formation using a
large diameter wellbore; this will be
4- known as "Well-01"; see FIGURE 01
= Approximately 0.5 to 1.6 km distant, drill and case a second single
lateral well from surface that ideally parallels (ie: within the limitations
imposed by actual drilling activities
and geologic conditions) the first. There is one 90 degree turn to form a
horizontal trunkline in the formation using a large diameter wellbore; this
will be known as"Well-02".
The exact (distance for the offset of these two wells (Well-01 to Well-02),
and the length of each trunkline well, are part of the engineering design and
optimization process. see
FIGURE 01
= During drilling process, gather data on the formation to understand and
map underground formations using Logging While Drilling ("LWD") and
Measurement While Drilling
("MWD") tools, standard in the oil and gas industry
0
= From the toe of the trunkline of Well-01, kick off a single lateral that
will drill horizontally, ideally perpendicular to both Well-01 and Well-02,
toward the toe of trunkline of Well-
o 02; this lateral will be known as Lat01-01; steer Lat01-01 MWD and LWD
methods augmented with the use radio-magnetic targeting tools to guide the
drill bit of Lat01-01 to
.471 intersect Well-02 as close to perpendicular as possible; see FIGURE
02
-0 = From the toe of Well-02 and a certain distance back from the
intersection of Lat01-01 and Well-02, kick off a single lateral well that will
drill ideally horizontally toward Well-01
.¨
" and ideally parallel to Lat01-01; this second lateral will be known
as Lat02-01 using the same process as described for Lat01-01; see FIGURE 03
4-1
=
From the trunkline of Well-01 and a certain distance back from the toe of the
intersection of Lat02-01 and Well-01, kick off a single lateral well that will
drill ideally horizontally
toward Well-02 and ideally parallel to Lat02-01 using the same process as
described for Lat01-01; this second lateral will be known as Lat01-02 ; see
FIGURE 04
0
= From the trunkline of Well-02 and a certain distance back from the toe of
the intersection of Lat01-02 and Well-02, kick off a single lateral well that
will drill ideally horizontally
toward Well-01 and ideally parallel to Lat01-02 using the same process as
described for Lat01-01; this second lateral will be known as Lat02-02 ; see
FIGURE 05
1¨ = Continue the process until the desired number of laterals have been
drilled; see FIGURE 06
= Run casing in each lateral well using standard completion techniques;
isolate the junction of the laterals and the trunklines using standard cement
and mechanical methods
CI
LL = Run completion string in the injection trunkline manifold to
control the flow to each lateral well, using standard sliding side door or
sliding sleeve methods for fluid diversion
0 = Run a completion string in the production trunkline manifold to
measure the temperature in the riser section and if possible, the trunkline
itself; the data from the production
lateral will be used to set the flow rate to each lateral, as controlled by
the valves in the injection trunkline manifold well
= Flow can now be implemented; to illustrate, WELL-01 is the cold water
injector and WELL-02 is the hot water producer; see FIGURE 07
TRINDADE RESERVOIR SERVICES INC.
10
Date Recue/Date Received 2020-11-25
+a
CO FIGURE 01: drilling of Well-01 and Well-02
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8 '*=
>,. = Well-01 and Well-
02 are horizontal wells, drilled from surface
c
ca and ideally are
parallel to each other, subject to drilling
c
=_ execution and actual geology encountered when drilling
a; r/
0 / Sci f
M Z'r ,-6' = The wellbores are
large diameter (ideally up to 1 ft diameter
,
8 õ..i.-
, in the trunkline) to optimize drilling,
working fluid retention
time, and allow for a completion string for flow measurement
and control
= The length of each trunkline manifold well in the reservoir,
4
e e j 5
44 1 i
a I /1' '
0 aq ,. and the distance
between the two trunkline wells, are
z k =
.,< ' . ., _ 0 determined by
engineering designs that will optimize heat
== 6-,
..J k
C7 e transfer, flow
rates and cost
1::
z g S
o
u.i =1/4". = The wells are cased and cemented using standard
thermal ,
kt.
ir. =,.,0
,, completion technology
z .0
0
0
TRINDADE RESERVOIR SERVICES INC.
11
=
Date Recue/Date Received 2020-11-25
ru FIGURE 02: drilling of Lat01-01 from Well-01 to Well-02
E
8
>,. = Lateral well LAT01-01
kicks off from the toe of WELL-01 and is
c
ca drilled ideally
perpendicular from WELL-01 toward WELL-02
c
=_ in the horizontal plane
M ,O ¨ I = MWD and LWD will be used to
steer the LAT01-01 toward
8 g ,,,,,,- , DRILL LAT01-01 FROM
'fv,, WELL01 TO WELL02
WELL-02, and radiomagnetics will be used in WELL-02 to
e .4 ..t,-
0 d ,R, guide the drillbit of
LAT01-01 to intersect WELL-02
,
z 4-
_ct 4, di 9 Sig
=_ , l = The lateral
wells are large wellbores to maximize the heat
. i
transfer surface area and the fluid retention time
15 ,
t:41 e
4
.% cc
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. _ 1
Z ' t-' i = The lateral wells will
be cased but not necessarily cemented
, /== ,,,
e over the entire horizontal length as cement has lower thermal
.`"., conductivity than
reservoir fluids +-
.)
UJ 4-
0 kt
LT. A .
e
z a e-
o u #-
u m ,;
TRINDADE RESERVOIR SERVICES INC.
12
=
Date Recue/Date Received 2020-11-25
ru FIGURE 03: drilling of Lat02-01 from Well-02 to Well-01
E
8 '*=
= Lateral well LAT02-01 kicks off from the toe of WELL-02 and is
>.
c drilled ideally
perpendicular from WELL-02 toward WELL-01 in the
ca
c horizontal plane
=_
.,-_ -- = MWD and LWD will be
used to steer the LAT02-01 toward WELL-01,
z 0 ,
8 F 4,,õ and radiomagnetics
will be used in WELL-01 to guide the drillbit of
, ,
LAT02-01 to WELL-01
,
...., 4-
1-
, = Data from the
drilling of LAT01-01 is incorporated to increase the
z ,,,=-
,o
_ct _, accuracy of LAT02-
01
=_
VI
15 = õ
,,,, .7õ - , . = The use of MWD and LWD from each
lateral is incorporated into
= DRILL LAT02-01 FROM
0 the drilling
execution program for subsequent laterals, which
4. t. il WELL02 '0 WELL01 ,
Z i IiV t,
P $ increases the
probability of success of accurately hitting the
. 4D
,- ,.''- targeted trunkline
manifold well
4µ
st .
z g ._-
= By drilling laterals, starting from the toe of the trunkline and
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0 +s,
A'z'
working back to the heel of the trunkline, the risk of completely
ir. AP
z 00
losing a well is greatly reduced; any adverse result at the toe of the
0 N.
well does not put the rest of the well at risk: a bridgeplug would be
.,/,.., , V,....,, At= set to seal off the
toe of the well and the rest of the well can be
,
safely utilized
TRINDADE RESERVOIR SERVICES INC.
13
Date Recue/Date Received 2020-11-25
ru FIGURE 04: drilling of Lat01-02 from Well-01 to Well-02
E
8
>,. = Lateral well LAT01-
02 kicks off from the toe of WELL-01 and is
c
ca
- drilled ideally perpendicular
from WELL-01 toward WELL-02 in
-
c
=_ the horizontal plane
z 4-. --= e = MWD and LWD will be
used to steer the LAT01-02 toward
WELL-02, and radiomagnetics will be used in WELL-02 to guide
. .
the drillbit of LAT01-02 to WELL-02
=47, w== , _
,..,-
z EE
1:2 (- ,,,e 1 ,
=¨ ¨ = Data from the
drilling of LAT01-01 and LAT02-01 are
_ ,,õ,
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incorporated to increase the accuracy of LAT01-02
0 M
Z / µmippr Pu
= LAT 01-01 FROM 0
.:.; -' WELL01 TO WELL02 ...-(3..
o ti.
17: -J 4C
,
#
Z 'g
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In /sv.'
Li 1.9
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0 N
o
0 ,
.-
4,
TRINDADE RESERVOIR SERVICES INC.
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=
Date Recue/Date Received 2020-11-25
ru FIGURE 05: drilling of Lat02-02 from Well-02 to Well-01
E
8 '*=
>,. = Lateral well LAT02-
02 kicks off from the toe of WELL-02 and is
c
ca drilled ideally
perpendicular from WELL-02 toward WELL-01 in
c
=_ the horizontal plane
0 /
M 7't 4S _ = MWD and LWD will be
used to steer the LAT02-02 toward
WELL-01, and radiomagnetics will be used in WELL-01 to
4-
,, _..
., ,
guide the drillbit of LAT02-02 to WELL-01
=47, -
,
z + 4,
_ct , 0
,
1 '' - = Data from the
drilling of LAT01-01, LAT02-01 and LAT01-02 are
=_
I At. 4/.,., ,
+a ¨ C7`' .01,
(1) = N; ':- 40. incorporated to
increase the accuracy of LAT02-02
0 4 : 07 ,
PI
z ,
= = /9
..J
UJ
0 s,
LT.
4;"
19
+
Z CP
CD 1;
Sp
o
TRINDADE RESERVOIR SERVICES INC.
15
=
Date Recue/Date Received 2020-11-25
ru FIGURE 06: final well construction with 6 laterals
E
8 '*=
>,. = The final construction
of the multilateral thermal collection
c
ca system is illustrated
for a system with 6 laterals between the
c
=_ two trunkline manifold wells
0 / /
M 7't
4,, _____________________ = The construction is not limited to only 6
laterals, but can be
8 g s ,
.,,4.- feasibly extended to have less than or
more than 6 laterals as
,
e .
0 .7õ,, ' .)= ¨
/:1- determined by
technical and economic optimization
z +
-b1 = As an example of
the proliferation of multilateral wells,
=_
4,,,,
+a µc,
q Maximum Reservoir Contact ("fishbone") wells are drilled to
have 10 or more laterals; see FIGURE 08 for actual results of 8
Z ' k 4,,-õ,
= = laterals,
achieved over 15 years ago by Saudi Aramco
17: -.1 .'z' = The trunkline concept
allows any number of laterals for the
z *--
`g
w thermal collection
system, provided the trunkline manifolds
o s.
ir. IF. can be drilled long
enough, with no additional risk of adverse
z Ø
0 ,v drilling results
U
TRINDADE RESERVOIR SERVICES INC.
16
=
Date Recue/Date Received 2020-11-25
ru FIGURE 07: Operation=. flow direction of the system
E
8
>,. = The final
construction of the multilateral thermal collection
c
ra ts system in this
representation is illustrated with 6 laterals
C p
between the two trunkline manifold wells to help envision the
a; LI
0 . operation of the
system
z w
8 ! Shhil = The construction is not
limited to only 6 laterals, but can be
e 8
'42 ZI2 4 feasibly extended to
have many more than 6 laterals if required
z w :z. , 4 4 1 iii 047145 0
.0 0
=_ = As an example of
the proliferation of multilateral wells,
,..,_ .
ul 0 "fishbone" wells
drilled for maximum reservoir contact can have
o u, 10 or more laterals extending from a single trunkline, in the
.,
z -
.:.; 0 context of oil
production; see FIGURE 08 for actual result of 8
laterals, achieved over 15 years ago by Saudi Aramco
1:: 0
,
z d
UJ 10 = To drill each
lateral, there is one 90-degree turn at the heel of the
o
ir. vertical well as it
transits to the horizontal trunkline manifold,
z
0 and then one kick off
point; this reduces the number of 90
0
kdegree turns by half compared to the Eavor system
,
TRINDADE RESERVOIR SERVICES INC.
17
=
Date Recue/Date Received 2020-11-25
ru FIGURE 08: Maximum reservoir contact wells (fish bone)
= Reference: "Drilling Maximum-Reservoir-
Contact Wells in the Shaybah Field", Dennis
co
Denney, Society of Petroleum Technology,
=_
September 2004
z
= Laterals are drilled by kicking off using a
whipstock, with the first lateral drilled from the
far end ("toe") of the trunk well, and each
z
additional lateral kicking off form a position
_ct
=_
that progresses toward the near end ("heel") of
+a
VI
the trunk well
= These actual wells were drilled over 15 years
ago and include the incorporation of
completions with sensors and valve control
UJ
systems
o m
= The novel method contains the key difference
0 of
90-degree laterals from the trunkline that are
drilled to and connect the trunkline of a second
well, making a closed loop system
TRINDADE RESERVOIR SERVICES INC.
18
Date Recue/Date Received 2020-11-25
+a
Summary
1. A new design for a multilateral well system for closed loop well
system that is applied to the "Clean Energy from
Oil Reservoir" and/or conventional geothermal energy production system
= 2. The new design allows for many more laterals in the underground heat
collection system; analogous methods
used in Saudi Aramco for open system oil production wells have achieved at
least 14 laterals from a trunkline
z well
3. The new design allows for large diameter casing that will enhance
heat conduction by increased surface area
and increased working fluid residence time
z
_ct 4. The new design reduces risk of missing the target well by reducing
the offset distance between the two
=_
trunkline manifold wells and changing the target from a small disk (the radius
of the target wellbore) to a
+a
cylinder (increased target area)
z 5. The new design reduces the risk of adverse drilling results by
removing one of the 90 degree turns in the
wellbore, simplifying the drilling process by reducing friction drag
associated with 90-degree turns
6. The new design reduces the risk of catastrophic lose of the well due
to repeatedly kicking off additional laterals
UJ from the same region of the host well; instead, all kick off points
are distributed along the length of the host
trunkline manifolds in order to distribute the "wear and tear" on the well
0 7. The new design allows for better sensors and valve control systems, as
deployed using conventional
surveillance and control methods
TRINDADE RESERVOIR SERVICES INC.
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=
Date Recue/Date Received 2020-11-25
Summary
0
In one aspect of the present disclosure, a method for drilling an array of
lateral wells for a closed-loop multilateral thermal capture system comprises
the
t= steps of: a) drilling a first horizontal well comprising a first
horizontal trunkline having a toe and a heel and a second horizontal well
comprising a second
ea horizontal trunkline having a toe and a heel, wherein the said toes of
the first and second horizontal trunklines are spaced apart by a first offset
distance and
the heels of the first and second horizontal trunklines are spaced apart by a
second offset distance; b) drilling a first ateral well kicking off from a
first kickoff
^ position of the first horizontal trunkline toward the second horizontal
trunkline so as to intersect the second horizontal trunkline at a first
intersection point,
wherein the first kickoff position is adjacent the toe of the first horizontal
trunkline; c) drilling a second lateral well kicking off from a second kickoff
position
4/1 of the second horizontal trunkline, the second kickoff position located
between the first intersection point and the heel of the second horizontal
trunkline,
= the second lateral well extending toward the first horizontal trunkline
so as to intersect the first horizontal trunkline at a second intersection
point, wherein
" the second intersection point is located between the first kickoff
position and the heel of the first horizontal trunkline; and d) repeating
steps lo) and c) so as
0 to drill at least a third lateral well and at least a fourth lateral wel
so as to form an array of lateral wells extending between the first and second
horizontal
e trunklines, and wherein each lateral well of the array of lateral wells
does not intersect any other lateral well in the array. A volume of heat-
retentive fluid
O flows through the heel of the first horizontal trunkline at a first flow
rate and through the array of lateral wells at a second flow rate, and the
first flow rate is
^ greater than or equal to the second flow rate.
=c The steps of drilling the at least first, second, third and fourth
lateral wells, in the method described above, may further include steering the
drilling of the
.1-'411 said lateral wells using measurement while drilling ("MWD") and
logging while drilling ("LWD") techniques. In addition to the use of MWD and
LWD
= techniques, the steps of drilling all lateral horizontal wells (the
first, second, third, etc) further includes positioning a plurality of
radiomagnetic targeting tools
13 within each of the first and second horizontal trunklines so as to
assist with steering the drilling of all lateral horizontal wells (first,
second, third, etc) to
intersect the horizontal trunkline.
In another aspect of the method, the data set generated by the MWD and LWD
techniques during the drilling of the first lateral well may be used during
the
< drilling of the second lateral well so as to increase the accuracy of
steering the drilling of the said second lateral well. Similarly, the data set
may further
I¨ include data obtained from the MWD and LWD techniques during the
drilling of the second, third, fourth and any subsequent lateral wells, and
that data set
Z may be used during the drilling of the third, fourth and any subsequent
lateral wells so as to increase the accuracy of steering of the drilling of
the said third,
LIJ fourth and any subsequent lateral wells.
0
In another aspect of the method, in some embodiments the first offset distance
is equal to the second offset distance. In some embodiments, both the first
0 and second horizontal trunklines are in a same horizontal plane. In some
embodiments, the diameter of a wellbore of each of the first and second
horizontal
wells is equal to or less than one foot, and/or a diameter of a wellbore of
each lateral well in the array of lateral wells is equal to or less than one
foot. Some
embodiments may include an array of lateral wells having at least four lateral
wells. In some embodiments, each lateral well in the array of lateral wells is
at
least partially encased in steel.
TRINDADE RESERVOIR SERVICES INC.
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=
Date Recue/Date Received 2020-11-25
Summary
In another aspect of the present disclosure, a closed-loop multilateral
thermal capture system comprises a first horizontal well
c having a first horizontal trunkline well and a second horizontal well
having a second horizontal trunkline well, the first and second
co horizontal trunkline wells spaced apart by a offset distance and
parallel to one another; a plurality of lateral wells extending from
.E the first horizontal trunkline well to the second horizontal trunkline
well, wherein each lateral well of the plurality of lateral wells
intersects both the first horizontal trunkline well and the second horizontal
trunkline well and each lateral well of the plurality of
= lateral wells is perpendicular to the first and second horizontal
trunkline wells; surface pipeline and facilities to ensure that a
z
closed loop is formed that incorporates the first wellhead of the first
horizontal well and a second wellhead of a second horizontal
O well so as to form a closed loop. The surface facilities include the
process units required to receive heated water from the
e production wellhead, use the hot water to generate electricity, and return
cooled water to the injection wellhead to feed the said
O heat-retentive fluid back into the underground reservoir to capture more
heat energy by flowing through the plurality of lateral
g wells in the hot formation, prior to production back up to the first
producer wellhead of the closed loop. The system further
70 includes data surveillance instrumentation in communication with a
trunkline well selected from a group comprising: the first
trunkline well, the second trunkline well, wherein the data surveillance
instrumentation could be configured to monitor the
I pressure, temperature and flow rate of the heat-retentive fluid in the
closed loop; and also includes flow control instrumentation
in fluid communication with a trunkline well selected from a group comprising:
the first trunkline well, the second trunkline well,
z wherein the flow control instrumentation is configured to control the
flow rate of the heat-retentive fluid flowing through the
.. plurality of lateral wells.
Zit
In some embodiments, the heat-retentive fluid comprises water. In some
embodiments, the plurality of lateral wells includes at
z least four lateral wells. In some embodiments, the diameter of a wellbore
of each of the first and second horizontal wells may be
Ili equal to or less than one foot, and/or a diameter of a wellbore of each
lateral well of the plurality of lateral wells has a diameter
rz that may be equal to or less than one foot. In some embodiments, each
lateral well of the plurality of lateral wells is at least
z partially encased in steel. In some embodiments, the first horizontal
well is an injection well and the second horizontal well is a
0 production well, wherein the flow control instrumentation is in fluid
communication with the second trunkline well of the
U production well. In some embodiments, the data surveillance
instrumentation is adjacent the second wellhead of the production
well and in fluid communication with the second trunkline well.
TRINDADE RESERVOIR SERVICES INC.
21
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Date Recue/Date Received 2020-11-25