CN106321041A - Later development method for reservoir production - Google Patents
Later development method for reservoir production Download PDFInfo
- Publication number
- CN106321041A CN106321041A CN201510364418.5A CN201510364418A CN106321041A CN 106321041 A CN106321041 A CN 106321041A CN 201510364418 A CN201510364418 A CN 201510364418A CN 106321041 A CN106321041 A CN 106321041A
- Authority
- CN
- China
- Prior art keywords
- oil
- formation
- perforated interval
- target locations
- development method
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/70—Combining sequestration of CO2 and exploitation of hydrocarbons by injecting CO2 or carbonated water in oil wells
Landscapes
- Earth Drilling (AREA)
Abstract
The invention relates to a later development method for reservoir production. The later development method for reservoir production comprises the steps that a plurality of drilling tools are arranged in a target stratum at intervals; all the drilling tools are placed to the oil-water interface in the target stratum by deepening a drill well; and first perforation sections on the drilling tools are blocked with blocking tools, and liquid is injected into the drilling tools so as to supplement oil displacement energy of the target stratum. The method has the advantage that energy supplementation for relatively independent crack units can be achieved.
Description
Technical field
The present invention relates to technical field of petroleum extraction, particularly relate to a kind of later development side for oil reservoir exploitation
Method.
Background technology
The exploitation of oil reservoir uses the mode of blowdown mostly.The mode of this blowdown is particularly well-suited to split
Seam type oil reservoir.In the later stage of blowdown, carrying out renwing stratum energy frequently with a method taken out, the method is
A kind of passive energy supplement method.Research shows, Fractured reservoir has relatively independent Crack Element and UNICOM to split
Seam unit, the Crack Element of UNICOM has the energy supplement in the external world, yield higher, independent Crack Element, water body energy
Measuring weak, the supplementary deficiency of outside energy, particularly in production cycle, aqueous change is little so that field output is relatively
Low.
As can be seen here, the exploitation for the relatively independent Crack Element in Fractured reservoir needs to provide one to be used for
The later development method of oil reservoir exploitation, to solve the displacement of reservoir oil that the relatively independent Crack Element in Fractured reservoir exists
The problem that energy is not enough.
Summary of the invention
For the problems referred to above, propose a kind of later development method for oil reservoir exploitation according to the present invention, including:
It is provided with multiple drilling tool by compartment in formation at target locations；By deepening drilling well so that each described spudder
Tool enters down at the oil-water interfaces to described formation at target locations；Blocked on each described drilling tool by capping tools
The first perforated interval, and in each described drilling tool, inject liquid respectively, to supplement the driving of described formation at target locations
Oil energy.So, when injecting liquid at the second perforated interval, liquid can penetrate into through the crack of formation at target locations
In rock, play the effect of moistening rock.Meanwhile, the substrate in formation at target locations is also improved to formation at target locations
In the efficiency of the crack displacement of reservoir oil.
It is also preferred that the left after the first perforated interval blocked on each described drilling tool, need to be at the oil of described formation at target locations
Close to perforation at the substrate of described oil-water interfaces bottom Ceng or bottom described oil reservoir, to drive in described formation at target locations
Crude oil permeate in the crack of described formation at target locations.
It is also preferred that the left described formation at target locations is configured with substrate oil storage unit body, described substrate oil storage unit body in order to
Accommodate described crude oil and liquid, between described crude oil and described liquid, form described oil-water interfaces.
It is also preferred that the left described first perforated interval is original oil recovery perforated interval.
It is also preferred that the left deepening after drilling well, need to be on each described drilling tool and close to the position of described oil-water interfaces
It is provided with the second perforated interval, blocks each described first perforated interval, and in each described second perforated interval, inject institute respectively
State liquid.So, just so that the liquid being injected in this drilling tool can be direct through this second perforated interval
Flowing underneath towards oil-water interfaces.
It is also preferred that the left described method is additionally included in the described liquid of injection cannot meet the displacement of reservoir oil energy of described formation at target locations
Time, by blocking after each described second perforated interval, open each described first perforated interval respectively, and each described the
In described substrate oil storage unit body, gas is injected, to supplement the displacement of reservoir oil energy of described formation at target locations at one perforated interval
Amount.
It is also preferred that the left described gas is upwards migrated along the crack of described formation at target locations, thus can be in described substrate oil storage
The pneumatic jack space having described gas is formed on the top of cell cube.So, owing to gas having elastic energy,
This elastic energy is utilized to carry out the displacement of reservoir oil energy on supplementary target stratum.
It is also preferred that the left described method is additionally included in the described liquid of injection or described gas cannot meet described formation at target locations
The displacement of reservoir oil energy time, by blocking each described second perforated interval, and to described base at each described first perforated interval
Matter oil storage unit body injects steam to heat the temperature of described crude oil.
It is also preferred that the left described capping tools is bridging plug.In this manner it is ensured that the first perforated interval on this drilling tool
Or second plugging effect of perforated interval, it is to avoid operationally, there is leakage of oil, leak or leak in above-mentioned each drilling tool
The phenomenon of gas.
It is also preferred that the left described gas is nitrogen, carbon dioxide or natural gas.
According to the present invention, the method has energy supplement problem excellent that can solve the problem that relatively independent Crack Element
Point, and also there is the advantage utilizing energy that the elastic energy of gas quickly improves substrate oil storage unit body.
It addition, the method also has by injecting steam, and come heating in crude oil, fall by the own temperature of steam
Low viscosity of crude, thus improve original mobility and the advantage improving recovery ratio.
Accompanying drawing explanation
Hereinafter based on embodiment reference accompanying drawing, the present invention will be described in more detail.In the drawings:
Fig. 1 is the steps flow chart schematic diagram of the later development method that the present invention exploits for oil reservoir.
Fig. 2 is the schematic diagram of the embodiment one of the later development method that the present invention exploits for oil reservoir.
Fig. 3 is the schematic diagram of the embodiment two of the later development method that the present invention exploits for oil reservoir.
In the accompanying drawings, identical parts use identical reference.Accompanying drawing is not according to actual scaling.
Detailed description of the invention
Below in conjunction with accompanying drawing, the invention will be further described.
As it is shown in figure 1, method of the invention is particularly suitable for solving substrate slit formation carbonate stone heavy crude reservoir phase
Energy supplement problem to independent Crack Element.
In embodiments herein, the method includes:
Step S410, is provided with multiple drilling tool by compartment in formation at target locations.It is increase oil production,
Multiple drilling tool can be set up in formation at target locations, and each drilling tool is worked simultaneously, thus improve and adopt
Oil mass, raising work efficiency.
In embodiments herein, this drilling tool can be sleeve pipe or oil pipe.
Step S420, the current location being in formation at target locations based on drilling tool, by the method deepening drilling well
Each drilling tool is made to enter down at the oil-water interfaces to formation at target locations.So, the end of each drilling tool can be made
End is respectively positioned on or close at oil-water interfaces.
Step S430, blocks the first perforated interval on each drilling tool by capping tools, and respectively to each drilling well
Instrument injects liquid, to supplement the displacement of reservoir oil energy of this formation at target locations.Specifically, owing to each drilling tool is not
Under when entering at the oil-water interfaces to formation at target locations, the first perforation can be offered in the corresponding position of each drilling tool
Section.After above-mentioned each drilling tool enters at the oil-water interfaces to formation at target locations down, need at each drilling tool
On the perisporium of the bottom at oil-water interfaces, offer the second perforated interval as described below.So, from ground to
When injecting liquid in this drilling tool, liquid can flow out at this second perforated interval along the inwall of this drilling tool,
And under the self gravitation effect of liquid, towards the water body flow below oil-water interfaces.Thus, due to liquid
Increase, oil-water interfaces can be made to raise, further, also improve the interface of crude oil, thus serve supplementary
The effect of the displacement of reservoir oil energy of this formation at target locations.
In embodiments herein, this liquid can be water or contain oil displacement assistant liquid etc..
As shown in Figures 2 and 3, in a preferred embodiment, after above-mentioned steps S430, i.e. exist
After blocking the first perforated interval 3 on each drilling tool 2, need to be bottom the oil reservoir of formation at target locations 1 or bottom oil reservoir
Perforation at the substrate of oil-water interfaces 5, thus drive crude oil the splitting to formation at target locations in this formation at target locations 1
Seam permeates.So, when injecting liquid at the second perforated interval 4, liquid can be through the crack of formation at target locations 1
And penetrate in rock, play the effect of moistening rock.Meanwhile, also improve substrate in formation at target locations 1 to
The efficiency of the crack displacement of reservoir oil in formation at target locations 1.Wherein, this formation at target locations 1 can be Fractured reservoir independence crack
Unit.
As in figure 2 it is shown, in embodiments herein, be provided with valve 21 at the upper port of this drilling tool 2.
The setting of this valve 21, can play the effect opened or closed controlling drilling tool 2.I.e. adopt when needs
During oil, by opening valve 21, thus realize opening of this drilling tool 2.When need not recover the oil, can lead to
The valve closing that reaches a standard door 21, thus realize the closedown of this drilling tool 2.
As shown in Figures 2 and 3, in a preferred embodiment, this formation at target locations 1 is configured with substrate storage
Oil cell cube 8, this substrate oil storage unit body 8 is in order to accommodate crude oil 6 and liquid 7, at crude oil 6 and liquid 7
Between formed oil-water interfaces 5.Specifically, this crude oil 8 is positioned at the top of liquid 7.
In a preferred embodiment, this first perforated interval 3 is original oil recovery perforated interval.This original oil recovery is penetrated
Hole segment distance oil-water interfaces 5 are farther out.
In a preferred embodiment, in above-mentioned steps S420, i.e. after deepening drilling well, need to be at each brill
It is provided with the second perforated interval 4 on well tool 2 and close to the position of these oil-water interfaces 5, blocks each first perforated interval 3,
And in each second perforated interval 4, inject liquid 7 respectively.So can play the displacement of reservoir oil of this formation at target locations 1 supplementary
The effect of energy.This second perforated interval 4 can be fluid injection perforated interval or water filling steam perforated interval.Specifically, this
Two perforated intervals 4 are located adjacent to the position of oil-water interfaces 5, so, just so that be injected into this drilling tool 2
In liquid can be through this second perforated interval 4 directly towards the flowing underneath of oil-water interfaces 5.Further, due to
Liquid below oil-water interfaces 5 is on the increase, thus improves the position of oil-water interfaces 5.
As it is shown on figure 3, in a preferred embodiment, the method is additionally included in this liquid 7 of injection cannot expire
During the displacement of reservoir oil energy of this formation at target locations 1 of foot, by blocking after each second perforated interval 4, open each first respectively and penetrate
Hole section 3, and the substrate oil storage unit body 8 in formation at target locations 1 injects at each first perforated interval 3 gas,
Displacement of reservoir oil energy with supplementary target stratum 1.
In a preferred embodiment, this gas is upwards migrated along the crack of formation at target locations 1, thus can be at base
The pneumatic jack space 81 having gas is formed on the top of matter oil storage unit body 8.
Specifically, when realizing recovering the oil by the way of fluid injection, along with substantial oil is along each drilling tool 2 towards ground
While returning on face, substantial amounts of gas can be taken away, it is thereby possible to cause formation at target locations 1 exists asking of degassing
Topic.Now, can be by injecting gas respectively in each drilling tool 2 so that gas is from this first perforated interval 3
Place flows out.Effluent air upwards can be migrated along the crack of formation at target locations 1 because of the effect of Gravity Separation, and migrates
Pneumatic jack space 81 to substrate oil storage unit body 8.So, owing to gas having elastic energy, this bullet is utilized
Performance carrys out the displacement of reservoir oil energy on supplementary target stratum 1.I.e. when having gas in pneumatic jack space 81, meeting exists
This pneumatic jack space 81 produces certain air pressure.Under the effect of gas pressure so that the interface of oil and gas moves down.
But, owing to the space of substrate oil storage unit body 8 is certain, occupy certain sky at the above-mentioned gas being injected into
Between (pneumatic jack space 81) time, pneumatic jack energy can be made to improve, thus for formation at target locations 1 the displacement of reservoir oil provide the displacement of reservoir oil
Energy.
After having injected liquid or gas injection in above-mentioned formation at target locations 1, crude oil can constantly on return, return upper
Meanwhile, certain liquids and gases can be taken away.In that way it is possible to the pressure balance that can affect in formation at target locations 1.
It is then desired to close each drilling tool 2 a period of time, with the pressure in balancing objective stratum 1.Avoid due to
Inject liquid or gas is too fast, cause generation water breakthrough or the drawback of has channeling.
In a preferred embodiment, the gas of above-mentioned injection can be nitrogen, carbon dioxide or natural gas etc..
As it is shown on figure 3, in a preferred embodiment, the method is additionally included in injection liquid or gas cannot
When meeting the displacement of reservoir oil energy of this formation at target locations 1, by blocking each second perforated interval 4, and at each first perforated interval
In substrate oil storage unit body 8, steam is injected, with the temperature of heating in crude oil at 3.Specifically, when crude oil not
Disconnected from this drilling tool 2 on when returning to ground, part crude oil may exist on the inwall of drilling tool 2 or
It is in the crack remaining in formation at target locations 1.It is thereby possible to because the toughness of crude oil is relatively big, cause the crude oil that slows down
The drawback of mobility.Therefore can be at the first perforated interval 3 in the substrate oil storage unit body 8 in formation at target locations 1
Inject steam.Steam self owing to being injected into has certain heat, therefore, it can play heating in crude oil
Effect.After crude oil is heated, owing to temperature raises, the viscosity of this crude oil is reduced, thus improve
The mobility of crude oil.Further, facilitate crude oil production, improve crude oil yield.
In embodiments herein, the temperature range of described steam is more than or equal to 100 degree and to be less than or equal to
320 degree.So, the effect of preferably heating in crude oil can just be played.Meanwhile, also avoid due to steam
Temperature is too high, causes so that crude oil occurs rotten drawback.
In embodiments herein, this capping tools can be bridging plug.In this manner it is ensured that this drilling tool 2
On the first perforated interval 3 or plugging effect of the second perforated interval 4, it is to avoid above-mentioned each drilling tool 2 operationally,
Phenomenon leakage of oil occurs, leaking or leaking gas.
In sum, the method in the present invention has the energy supplement problem that can solve the problem that relatively independent Crack Element
Advantage, and also there is the excellent of the energy that utilizes the elastic energy of gas quickly to improve substrate oil storage unit body
Point.It addition, the method also has by injecting steam, and heat thickness by self heat energy of steam
Crude oil, thus improve original mobility and improve recovery ratio advantage.
Although by reference to preferred embodiment, invention has been described, but without departing from the scope of the present invention
In the case of, it can be carried out various improvement and parts therein can be replaced with equivalent.Especially, only
Otherwise there is structural hazard, the every technical characteristic being previously mentioned in each embodiment all can combine in any way
Come.The invention is not limited in specific embodiment disclosed herein, but include falling within the scope of the appended claims
All technical schemes.
Claims (10)
1. for a later development method for oil reservoir exploitation, including:
It is provided with multiple drilling tool by compartment in formation at target locations；
By deepening drilling well so that each described drilling tool enters down the oil-water interfaces to described formation at target locations
Place；
The first perforated interval on each described drilling tool is blocked by capping tools, and respectively to each described spudder
Tool injects liquid, to supplement the displacement of reservoir oil energy of described formation at target locations.
Later development method for oil reservoir exploitation the most according to claim 1, it is characterised in that in envelope
After the first perforated interval on stifled each described drilling tool, need to be bottom the oil reservoir of described formation at target locations or described oil reservoir
Bottom is close to perforation at the substrate of described oil-water interfaces, to drive the crude oil in described formation at target locations to described target
The crack on stratum is permeated.
Later development method for oil reservoir exploitation the most according to claim 2, it is characterised in that described
Being configured with substrate oil storage unit body in formation at target locations, described substrate oil storage unit body is in order to accommodate described crude oil and liquid
Body, forms described oil-water interfaces between described crude oil and described liquid.
Later development method for oil reservoir exploitation the most according to claim 1, it is characterised in that described
First perforated interval is original oil recovery perforated interval.
Later development method for oil reservoir exploitation the most according to claim 3, it is characterised in that adding
After deep drilling well, the second perforated interval need to be provided with on each described drilling tool and close to the position of described oil-water interfaces,
Block each described first perforated interval, and in each described second perforated interval, inject described liquid respectively.
Later development method for oil reservoir exploitation the most according to claim 5, it is characterised in that described
When method is additionally included in the displacement of reservoir oil energy that the described liquid of injection cannot meet described formation at target locations, by blocking each institute
After stating the second perforated interval, open each described first perforated interval respectively, and to described at each described first perforated interval
Substrate oil storage unit body injects gas, to supplement the displacement of reservoir oil energy of described formation at target locations.
Later development method for oil reservoir exploitation the most according to claim 6, it is characterised in that described
Gas is upwards migrated along the crack of described formation at target locations, thus can be formed at the top of described substrate oil storage unit body
There is the pneumatic jack space of described gas.
Later development method for oil reservoir exploitation the most according to claim 6, it is characterised in that described
Method is additionally included in when injecting displacement of reservoir oil energy that described liquid or described gas cannot meet described formation at target locations, logical
Cross and block each described second perforated interval, and note in described substrate oil storage unit body at each described first perforated interval
Enter steam to heat the temperature of described crude oil.
Later development method for oil reservoir exploitation the most according to claim 1, it is characterised in that described
Capping tools is bridging plug.
Later development method for oil reservoir exploitation the most according to claim 6, it is characterised in that institute
Stating gas is nitrogen, carbon dioxide or natural gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510364418.5A CN106321041B (en) | 2015-06-26 | 2015-06-26 | A kind of later development method for oil reservoir exploitation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510364418.5A CN106321041B (en) | 2015-06-26 | 2015-06-26 | A kind of later development method for oil reservoir exploitation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106321041A true CN106321041A (en) | 2017-01-11 |
| CN106321041B CN106321041B (en) | 2019-02-01 |
Family
ID=57721431
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510364418.5A Active CN106321041B (en) | 2015-06-26 | 2015-06-26 | A kind of later development method for oil reservoir exploitation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106321041B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1834403A (en) * | 2006-04-17 | 2006-09-20 | 尤尼斯油气技术（中国）有限公司 | Hot air filling balance oil recovery technique 'zhanqian' mountain oil reservoir |
| CN101793138A (en) * | 2010-03-10 | 2010-08-04 | 大庆油田有限责任公司 | Hydrocyclone and screw pump combined downhole oil-water separation method |
| CN101942984A (en) * | 2010-01-27 | 2011-01-12 | 中国石油化工股份有限公司 | Fracture-cave type carbonate reservoir waterflooding oil replacement recovery method |
| RU2431744C1 (en) * | 2010-04-16 | 2011-10-20 | Открытое акционерное общество "Татнефть" имени В.Д. Шашина | Procedure for extraction of high viscous oil and bitumen with application of horizontal producing and horizontal-inclined wells |
| CN103742124A (en) * | 2013-12-28 | 2014-04-23 | 中国石油天然气股份有限公司 | Method for re-separating produced liquid of underground oil-water separation co-well injection and production well |
-
2015
- 2015-06-26 CN CN201510364418.5A patent/CN106321041B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1834403A (en) * | 2006-04-17 | 2006-09-20 | 尤尼斯油气技术（中国）有限公司 | Hot air filling balance oil recovery technique 'zhanqian' mountain oil reservoir |
| CN101942984A (en) * | 2010-01-27 | 2011-01-12 | 中国石油化工股份有限公司 | Fracture-cave type carbonate reservoir waterflooding oil replacement recovery method |
| CN101793138A (en) * | 2010-03-10 | 2010-08-04 | 大庆油田有限责任公司 | Hydrocyclone and screw pump combined downhole oil-water separation method |
| RU2431744C1 (en) * | 2010-04-16 | 2011-10-20 | Открытое акционерное общество "Татнефть" имени В.Д. Шашина | Procedure for extraction of high viscous oil and bitumen with application of horizontal producing and horizontal-inclined wells |
| CN103742124A (en) * | 2013-12-28 | 2014-04-23 | 中国石油天然气股份有限公司 | Method for re-separating produced liquid of underground oil-water separation co-well injection and production well |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106321041B (en) | 2019-02-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105114048B (en) | A kind of staged fracturing of horizontal well single-well injection-production oil production method | |
| CN104563990B (en) | One kind bores blanking integration and heat injection cooperative reinforcing coal bed gas extraction method | |
| CN103422838B (en) | Carbon dioxide huff and puff enhanced oil production method | |
| CN100398779C (en) | Hot air filling balance oil recovery technique 'zhanqian' mountain oil reservoir | |
| CN107100605A (en) | A kind of method that dual horizontal well circulation supercritical carbon dioxide develops hot dry rock | |
| CN103939071B (en) | A kind of horizontal well steam flooding well web frame and steam drive method | |
| CN101942984A (en) | Fracture-cave type carbonate reservoir waterflooding oil replacement recovery method | |
| CN105138029B (en) | The compress control method of note nitrogen volume increase coal bed gas | |
| CN105756634A (en) | Method for achieving interval waterflood swallowing-spitting oil exploitation among multi-stage fractured horizontal well cracks | |
| CN104895537A (en) | Water-injection oil-replacement mining method applicable to fracture-cavity type carbonatite condensate gas reservoirs | |
| CN105822276A (en) | Inter-crack space synchronous water injection-oil extraction method of multistage fracturing horizontal well | |
| CN105003235A (en) | Method for improving condensate oil recovery ratio through injecting water into fracture-cave type carbonate condensate gas reservoir | |
| CN104895541A (en) | Method for breaking interlayer in oil layer during double horizontal well SAGD exploitation | |
| CN104847322A (en) | Method for improving recovery efficiency for deep common thickened oil water drive-converting into-steam flooding | |
| CN106884637A (en) | Shale gas thermal process and system | |
| CN105863581A (en) | Oil extraction method for water controlling and oil increasing of buried hill oil reservoir high-water-cut oil-producing well | |
| CN106837277A (en) | Oil reservoir recovery method and device | |
| CN112983358A (en) | Method for exploiting coal bed gas by injecting carbon dioxide between same well seams of horizontal well | |
| CN206249778U (en) | A kind of straight well-horizontal well SAGD draining principle test devices | |
| CN102606123B (en) | Steam flooding assisted gravity drainage oil extracting method | |
| CN109025940B (en) | CO for tight oil reservoir2Fracturing oil displacement integrated oil extraction method | |
| CN106321041A (en) | Later development method for reservoir production | |
| CN104271878B (en) | The anti-coning of steam/coning technology means to save the situation | |
| CN201972681U (en) | Heat injection and mechanical oil extraction integrated device | |
| CN204252886U (en) | A kind of Multilateral Wells pressure break tieback releasing tool |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |