[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

CN102288064B - Protection method for joint stop of air cooling island and unit - Google Patents

Protection method for joint stop of air cooling island and unit Download PDF

Info

Publication number
CN102288064B
CN102288064B CN 201110163913 CN201110163913A CN102288064B CN 102288064 B CN102288064 B CN 102288064B CN 201110163913 CN201110163913 CN 201110163913 CN 201110163913 A CN201110163913 A CN 201110163913A CN 102288064 B CN102288064 B CN 102288064B
Authority
CN
China
Prior art keywords
air
precerving liquid
filling
unit
filling apparatus
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.)
Active
Application number
CN 201110163913
Other languages
Chinese (zh)
Other versions
CN102288064A (en
Inventor
刘克成
龙潇
何彩燕
桑俊珍
孙小军
莫宗保
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
State Grid Corp of China SGCC
Electric Power Research Institute of State Grid Hebei Electric Power Co Ltd
Hebei Electric Power Construction Adjustment Test Institute
Original Assignee
State Grid Corp of China SGCC
Electric Power Research Institute of State Grid Hebei Electric Power Co Ltd
Hebei Electric Power Construction Adjustment Test Institute
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by State Grid Corp of China SGCC, Electric Power Research Institute of State Grid Hebei Electric Power Co Ltd, Hebei Electric Power Construction Adjustment Test Institute filed Critical State Grid Corp of China SGCC
Priority to CN 201110163913 priority Critical patent/CN102288064B/en
Publication of CN102288064A publication Critical patent/CN102288064A/en
Application granted granted Critical
Publication of CN102288064B publication Critical patent/CN102288064B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Examining Or Testing Airtightness (AREA)

Abstract

The invention discloses a protection method for joint stop of an air cooling island and a unit. The method comprises the following steps of: 1) adjusting parameters before the air cooling unit is stopped; 2) injecting maintenance solution; 3) stopping the unit; and 4) draining. The method has the advantages that: octadecylamine is vaporized at the temperature of more than 450 DEG C, the gaseous octadecylamine enters a unit thermodynamic system and an air cooling system along with steam together to form a layer of hydrophobic protective film on the metal surface, and air is isolated from the metal after the unit is stopped, so that air is prevented from oxidizing and corroding the metal surface in relatively damp environment, a great amount of water is not required to be used for rinsing a system in the process of restarting the unit, the qualification time of iron content in circulating water during starting is effectively shortened, and the using amount of fuel oil or fuel coal is saved during starting.

Description

A kind of Air-Cooling Island and Air-cooled Unit associating Shut-down Protection method
Technical field
The present invention relates to a kind of Air-Cooling Island and the unit method of stopping using, particularly a kind of Air-Cooling Island and Air-cooled Unit associating Shut-down Protection method.
Background technology
The steam of discharging after the steam turbine acting in the thermal power plant mainly adopts dual mode to carry out cooling and reclaims its condensate water, i.e. water cooling (water-cooled) and air cooling (air cooling).The most of Water Cooling Technology that adopts in existing thermal power plant, due to the water evaporation loss, need to consume a large amount of water, along with expanding economy, water resource day by day in short supply, the water intaking price rises year by year, directly causes the thermal power plant cost to increase, and the environmental issue that the while moisture contamination is brought is also more and more outstanding.Therefore traditional Water Cooling Technology more and more has been not suitable with the requirement in epoch, and air cooling technique is developed and used in countries in the world gradually, comprises indirectly coolingly and directly cooling, and application at present is Direct Air-Cooling Technology comparatively generally.
Adopt the cooling system of Direct Air-Cooling Technology to be called Direct Air-cooled Unit, the Air-Cooling Island of Direct Air-cooled Unit is a huge metal heat sink, its material major part is carbon steel, it is generally acknowledged that the corrosion of carbon steel is take electrochemical corrosion as main, and chemical attack is take the oxygen uptake corrosion as main, and Air-Cooling Island is during stopping transport, and internal environment is moist, relative humidity is close to saturated, so the oxygen uptake serious corrosion.
Air cooling island of direct air cooling unit is huge, and vapour, liquid phase coexist, and gas flow process complexity is various.Present Domestic does not also have ripe technology and research to Direct Air-cooled Unit and Air-Cooling Island maintenance outage, can not solve preferably the corrosion during Air-Cooling Island is stopped transport; When causing unit starting, iron content for a long time can not be qualified, wastes a large amount of wash waters; Extend the unit starting time, the waste great amount of fuel oil.The technical barrier such as the conventional rack shutdown maintaining method has that medicament dissolution is poor, phase skewness, maintenance effect are poor.
Summary of the invention
Technical problem to be solved by this invention is to provide a kind of Air-Cooling Island and Air-cooled Unit associating Shut-down Protection method, can effectively save flushing water, capable of saving fuel oil, and the qualified time of iron in circulating content can greatly shorten unit starting the time.
For solving the problems of the technologies described above, the technical solution used in the present invention is: a kind of Air-Cooling Island and Air-cooled Unit associating Shut-down Protection method, and described Air-cooled Unit comprises superheater, drum, economizer, pre feedwater pump, oxygen-eliminating device, condensate pump, diamine filling apparatus, phosphate filling apparatus and exhaust apparatus; Also comprise respectively the special-purpose Precerving liquid filling apparatus that docks with Air-Cooling Island input pipe and efferent duct and exhaust apparatus efferent duct; Described special-purpose Precerving liquid filling apparatus comprises Precerving liquid case and dispenser pump; Described exhaust apparatus docks with Air-Cooling Island; Its associating Shut-down Protection method comprises the following steps:
One) the Air-cooled Unit cunning is stopped front parameter adjustment; 1) dissolve respectively the furnace stopping maintenance liquid of desired concn in special-purpose Precerving liquid filling apparatus, diamine filling apparatus, phosphate filling apparatus; 2) the Air-cooled Unit cunning is stopped in front 3 hours, strengthen the feedwater ammonia residual, improve stove water water sample pH value to 9.5-10, the diamine filling apparatus of the condensate water of stopping transport subsequently and feedwater, Lu Shui stop adding phosphate, and carry out blow-off of boiler water, make that in stove water, phosphate content remains on below 0.5mg/L; Boiler feedwater flow remains on 600t/h, and steam water-level is closed continuous blowdown system of boiler lower than ordinary water level 10-100mm; 3) on-line chemical monitoring instrument the electrical conductivity table is stopped transport and closes isolating door before pH table, hydrogen post;
Two) filling Precerving liquid; The unit cunning stop to rated load 50% the time, and keep stable operation of unit, adjust the capacity of Air-cooled Unit secondary bypass, keeping the delivery temperature in exhaust apparatus exit is 60 ℃-70 ℃;
1) pass through special-purpose Precerving liquid filling apparatus to exhaust apparatus efferent duct filling Precerving liquid 700-800 kilogram;
2) when the superheated steam temperature during less than 450 ℃, by special-purpose Precerving liquid filling apparatus to the first condensate pump and the second condensate pump entrance filling Precerving liquid, start simultaneously the diamine filling apparatus to water supply preposition pump intake filling Precerving liquid, start the phosphate filling apparatus Precerving liquid of annotating in the drum; The above-mentioned Precerving liquid filling time is the 2-3 left and right, and during the Precerving liquid filling, superheat steam temperature should remain on 350 ℃-450 ℃;
Three) shut down; After the Precerving liquid filling was complete, the operational factor when Direct Air-cooled Unit is annotated according to Precerving liquid continued stable operation one hour; And continue sliding stopping, when superheater pressure was 2.0-2.4MPa, boiler is with pressure to discharge water, and residual heat drying;
Four) draining; With the hydrophobic discharge in Direct Air-cooled Unit.
Described Precerving liquid is octadecylamine.
the beneficial effect that adopts technique scheme to produce is: the Direct Air-cooled Unit cunning is stopped in process at system's a plurality of position filling octadecylamine, octadecylamine is in vaporization more than 450 ℃, the octadecylamine of gaseous state is along with steam enters unit thermodynamic system and air cooling system, form the layer of hydrophobic diaphragm in the metal surface, after shutting down, that air and metal is isolated, thereby prevent that air in relative wet environment is to the oxide etch of metal surface, need not to use a large amount of flushing waters that system is rinsed in the unit restart procedure, effectively shorten the qualified time of iron in circulating content when starting, save fuel oil or coal-fired use amount when starting.
Description of drawings
Fig. 1 is Air-Cooling Island and Air-cooled Unit structural representation.
In the accompanying drawings: 1, superheater; 2, stove water sampling mouth; 3, drum; 4, the first Precerving liquid filling point; 5, the second Precerving liquid filling point; 6, Air-Cooling Island; 7, the 3rd Precerving liquid filling point; 8, exhaust apparatus; 9, the 4th Precerving liquid filling point; 10, the first condensate pump; 11, the second condensate pump; 12, special-purpose Precerving liquid filling apparatus; 13, condensed water sampling point; 14, oxygen-eliminating device; 15, pre feedwater pump; 16, the 5th Precerving liquid filling point; 17, main feedwater sample point; 18, economizer; 19, sampler; 20, main steam sample point.
Further the present invention is described in detail below in conjunction with accompanying drawing.
The specific embodiment
A kind of Air-Cooling Island and Air-cooled Unit associating Shut-down Protection method, described Air-cooled Unit comprises superheater 1, drum 3, economizer 18, pre feedwater pump 15, oxygen-eliminating device 14, the first condensate pump 10, the second condensate pump 11, diamine filling apparatus, phosphate filling apparatus and exhaust apparatus 8; Also comprise respectively the special-purpose Precerving liquid filling apparatus 12 that docks with Air-Cooling Island 6 input pipes and efferent duct and exhaust apparatus 8 input pipes; Described special-purpose Precerving liquid filling apparatus 12 comprises Precerving liquid case and dispenser pump; Described exhaust apparatus 8 docks (referring to accompanying drawing 1) with Air-Cooling Island 6; Its key improvements is, unites the Shut-down Protection method and comprises the following steps:
One) the Air-cooled Unit cunning is stopped front parameter adjustment; 1) dissolve respectively the furnace stopping maintenance liquid of desired concn in special-purpose Precerving liquid filling apparatus 12, diamine filling apparatus, phosphate filling apparatus; 2) the Air-cooled Unit cunning is stopped in front 3 hours, strengthen the feedwater ammonia residual, improve stove water water sample pH value to 9.5-10, the diamine filling apparatus of the condensate water of stopping transport subsequently and feedwater, Lu Shui stop adding phosphate, and carry out blow-off of boiler water, make that in stove water, phosphate content remains on below 0.5mg/L; Boiler feedwater flow remains on 600t/h, and drum 3 water levels are closed continuous blowdown system of boiler lower than ordinary water level 10-100mm; 3) on-line chemical monitoring instrument the electrical conductivity table is stopped transport and closes isolating door before pH table, hydrogen post; At sliding stopped transport in first three hour diamine filling apparatus and the phosphate filling apparatus of stopping, and special-purpose Precerving liquid filling apparatus arranges three outlets, three outlet respectively with the second Precerving liquid filling points, the 3rd Precerving liquid filling point and the 4th Precerving liquid filling points are communicated with, wherein the second Precerving liquid filling point and the 3rd Precerving liquid filling point are located at respectively on the discharge duct of exhaust apparatus, and the 4th Precerving liquid filling point is located at the first condensate pump and the second condensate pump porch; And diamine filling apparatus and phosphate filling apparatus invariant position, the diamine filling apparatus is communicated with the water supply preposition pump intake, and phosphate filling apparatus and drum are communicated with; Before the filling Precerving liquid, dissolve the Precerving liquid of desired concn, i.e. octadecylamine in the Precerving liquid storage bin of diamine filling apparatus, special-purpose Precerving liquid filling apparatus and in the phosphate filling apparatus according to the standard that can make stove water water sample PH reach 9.5-10;
Two) filling Precerving liquid; The unit cunning stop to rated load 50% the time, can slide and stop to 300MW such as the rated load unit that is 600MW, keep stable operation of unit, adjust the capacity of Air-cooled Unit secondary bypass, keeping the delivery temperature in exhaust apparatus exit is 60 ℃-70 ℃;
1) by special-purpose Precerving liquid filling apparatus 12 to exhaust apparatus 8 efferent ducts filling Precerving liquid 700-800 kilograms, namely at the octadecylamine of the second Precerving liquid filling point and the 3rd Precerving liquid filling point filling 700-800 kilogram;
2) when the superheated steam temperature during less than 450 ℃, by special-purpose Precerving liquid filling apparatus 12 to the first condensate pump 10 and the second condensate pump 11 entrances filling Precerving liquids, start simultaneously the diamine filling apparatus to pre feedwater pump 15 entrance filling Precerving liquids, start the phosphate filling apparatus to the interior filling Precerving liquid of drum 3, the above-mentioned Precerving liquid filling time is 2-3 hour, and during the Precerving liquid filling, superheat steam temperature should remain on 350 ℃-450 ℃, the detection of taking a sample of the water that circulates at any time to unit in the Precerving liquid filling process or steam, for easy to detect, one cover sampler 19 and four sample points are set, four sample points comprise the stove water sampling point 2 of being located on drum 3, be located at the main steam sample point 20 on main steam line, be located at condensed water sampling point 13 and the main feedwater sample point 17 of being located at pre feedwater pump 15 outputs in the first condensate pump 10 and the second condensate pump 11 outlets, during Precerving liquid filling by sampler to main steam, main feedwater, condensate water and stove water sampling are analyzed, wherein pH value and electrical conductivity detected once in every ten minutes, the per half an hour detection of iron-holder and octadecylamine content once, when detected parameters exceeds allowed band, adjust Precerving liquid adding amount and filling speed according to relevant regulations,
Three) shut down; After the Precerving liquid filling was complete, the operational factor when Direct Air-cooled Unit is annotated according to Precerving liquid continued stable operation one hour; And continue sliding stopping, when superheater pressure was 2.0-2.4MPa, boiler is with pressure to discharge water, and residual heat drying;
Four) draining; With the hydrophobic discharge in Direct Air-cooled Unit, mainly get rid of oxygen-eliminating device, condenser hotwell, high-pressure heater vapour side and low-pressure heater vapour side are hydrophobic etc. should in time drain.
Described Precerving liquid is octadecylamine; octadecylamine is in vaporization more than 450 ℃; the octadecylamine of gaseous state is along with steam enters unit thermodynamic system and air cooling system; form the layer of hydrophobic diaphragm in the metal surface; after shutting down, that air and metal is isolated; thereby prevent that air in relative wet environment is to the oxide etch of metal surface; need not to use a large amount of flushing waters that system is rinsed in the unit restart procedure; effectively shorten the qualified time of iron in circulating content when starting, save fuel oil or coal-fired use amount when starting.

Claims (2)

1. an Air-Cooling Island and Air-cooled Unit associating Shut-down Protection method, described Air-cooled Unit comprises superheater (1), drum (3), economizer (18), pre feedwater pump (15), oxygen-eliminating device (14), the first condensate pump (10), the second condensate pump (11), diamine filling apparatus, phosphate filling apparatus and exhaust apparatus (8); Also comprise respectively the special-purpose Precerving liquid filling apparatus (12) that docks with Air-Cooling Island (6) input pipe and efferent duct and exhaust apparatus (8) efferent duct; Described special-purpose Precerving liquid filling apparatus (12) comprises Precerving liquid case and dispenser pump; Described exhaust apparatus (8) docks with Air-Cooling Island (6); It is characterized in that, associating Shut-down Protection method comprises the following steps:
One) the Air-cooled Unit cunning is stopped front parameter adjustment; 1) dissolve respectively the furnace stopping maintenance liquid of desired concn in special-purpose Precerving liquid filling apparatus (12), diamine filling apparatus, phosphate filling apparatus; 2) the Air-cooled Unit cunning is stopped in front 3 hours, strengthen the feedwater ammonia residual, improve stove water water sample pH value to 9.5-10, the diamine filling apparatus of the condensate water of stopping transport subsequently and feedwater, Lu Shui stop adding phosphate, and carry out blow-off of boiler water, make that in stove water, phosphate content remains on below 0.5mg/L; Boiler feedwater flow remains on 600t/h, and drum (3) water level is closed continuous blowdown system of boiler lower than ordinary water level 10-100mm; 3) on-line chemical monitoring instrument the electrical conductivity table is stopped transport and closes isolating door before pH table, hydrogen post;
Two) filling Precerving liquid; The unit cunning stop to rated load 50% the time, keep stable operation of unit, adjust the capacity of Air-cooled Unit secondary bypass, keeping the delivery temperature in exhaust apparatus exit is 60 ℃-70 ℃;
1) pass through special-purpose Precerving liquid filling apparatus (12) to exhaust apparatus (8) efferent duct filling Precerving liquid 700-800 kilogram;
2) when the superheated steam temperature during less than 450 ℃, by special-purpose Precerving liquid filling apparatus (12) to the first condensate pump (10) and the second condensate pump (11) entrance filling Precerving liquid, start simultaneously the diamine filling apparatus to pre feedwater pump (15) entrance filling Precerving liquid, start the phosphate filling apparatus to the interior filling of drum (3) Precerving liquid; The above-mentioned Precerving liquid filling time is 2-3 hour, and during the Precerving liquid filling, superheat steam temperature should remain on 350 ℃-450 ℃;
Three) shut down; After the Precerving liquid filling was complete, the operational factor when Direct Air-cooled Unit is annotated according to Precerving liquid continued stable operation one hour; And continue sliding stopping, when superheater pressure was 2.0-2.4MPa, boiler is with pressure to discharge water, and residual heat drying;
Four) draining; With the hydrophobic discharge in Direct Air-cooled Unit.
2. a kind of Air-Cooling Island according to claim 1 and Air-cooled Unit are united the Shut-down Protection method, and it is characterized in that: described Precerving liquid is octadecylamine.
CN 201110163913 2011-06-17 2011-06-17 Protection method for joint stop of air cooling island and unit Active CN102288064B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN 201110163913 CN102288064B (en) 2011-06-17 2011-06-17 Protection method for joint stop of air cooling island and unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN 201110163913 CN102288064B (en) 2011-06-17 2011-06-17 Protection method for joint stop of air cooling island and unit

Publications (2)

Publication Number Publication Date
CN102288064A CN102288064A (en) 2011-12-21
CN102288064B true CN102288064B (en) 2013-06-12

Family

ID=45334695

Family Applications (1)

Application Number Title Priority Date Filing Date
CN 201110163913 Active CN102288064B (en) 2011-06-17 2011-06-17 Protection method for joint stop of air cooling island and unit

Country Status (1)

Country Link
CN (1) CN102288064B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103423728A (en) * 2013-08-13 2013-12-04 南京钢铁股份有限公司 Boiler thermal state sliding-parameter shutdown method

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102818398B (en) * 2012-07-25 2015-01-07 北京冶联科技有限公司 Intelligent air cooling island and control method thereof
CN103322828A (en) * 2013-05-23 2013-09-25 西安热工研究院有限公司 Shutdown protection device of direct air cooled condenser of thermal power plant
CN105220136B (en) * 2014-06-11 2018-02-09 北京京桥热电有限责任公司 A kind of blowing out anti-corrosion guard method of waste heat boiler unit
CN110686230A (en) * 2019-10-10 2020-01-14 王彦淳 Method for adjusting pH value of boiler feed water
CN110819996A (en) * 2019-11-15 2020-02-21 广州珠江天然气发电有限公司 High-temperature film forming maintenance method for gas-steam combined cycle unit
CN112984613A (en) * 2021-03-02 2021-06-18 华能山东石岛湾核电有限公司 Maintenance method for nuclear power plant heating system during shutdown period

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100436938C (en) * 2006-10-12 2008-11-26 山西省电力公司电力科学研究院 Method for directly treating air cooling drum boiler unit water supply
CN100432612C (en) * 2007-01-23 2008-11-12 西安利能科技有限责任公司 Shutdown maintaining method for directly air cooling system
JP2008249275A (en) * 2007-03-30 2008-10-16 Aquas Corp Injection method of water treatment agent
CN101655335B (en) * 2008-08-19 2011-08-03 华北电力科学研究院有限责任公司 Device and method for thermal cleaning of direct air cooling system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103423728A (en) * 2013-08-13 2013-12-04 南京钢铁股份有限公司 Boiler thermal state sliding-parameter shutdown method
CN103423728B (en) * 2013-08-13 2014-12-31 南京钢铁股份有限公司 Boiler thermal state sliding-parameter shutdown method

Also Published As

Publication number Publication date
CN102288064A (en) 2011-12-21

Similar Documents

Publication Publication Date Title
CN102288064B (en) Protection method for joint stop of air cooling island and unit
CN106016230B (en) A kind of Start-up Systems for Direct-through Boilers and method
CN106122929B (en) A add medicine and sampling system for combined cycle generating set multi-pressure exhaust-heat boiler
CN102997215A (en) Quick start method and system of combined cycle unit
CN206369204U (en) A kind of pipeline for gas flue gas waste heat recovery system
CN108644016A (en) Gas-steam combined cycle set therrmodynamic system stops spare corrosion protection technique
CN206018578U (en) A add medicine and sampling system for combined cycle generating set multi-pressure exhaust-heat boiler
RU2403320C2 (en) Method for anti-corrosion protection of steam and water circuits of power plants
CN206267892U (en) Turbo-generator Set steam circulation
CN204153755U (en) Energy-saving fuel steam boiler system
CN216813788U (en) Liquid corrosion inhibitor gasification equipment
RU96283U1 (en) PASSIVE HEAT REMOVAL SYSTEM THROUGH A STEAM GENERATOR
CN105220136B (en) A kind of blowing out anti-corrosion guard method of waste heat boiler unit
CN106524106B (en) The heat pump system of steam is generated using low-grade heat source
CN114171218B (en) Nuclear power plant condenser leakage detection system
CN115773492A (en) Wet nitrogen charging maintenance method for quick start of waste heat boiler of gas turbine
Ruqing et al. Cycle and Harm of Main Pollutants in Thermal System of Gas Turbiner
CN207501129U (en) One kind is used for steam power plant's steam heat recovery system
CN101403574B (en) Dual-function non-condensing gas cleaner
CN207716941U (en) A kind of gas fired-boiler graphite condenser
CN207351239U (en) Gas utilization unit steam condensate (SC) energy-saving recovery device
CN217584388U (en) High temperature gas cooled reactor steam generator secondary side hot dry air maintenance system
CN205679104U (en) Super heat-conductive pipe quick-replaceable flue gas waste heat recoverer
CN215893933U (en) Simple low-temperature economizer leakage detection device
CN205038970U (en) Nuclear power station seawater desalination and residual heat removal system

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
ASS Succession or assignment of patent right

Owner name: STATE ELECTRIC NET CROP. HEBEI ELECTRIC POWER CORP

Effective date: 20130105

C41 Transfer of patent application or patent right or utility model
COR Change of bibliographic data

Free format text: CORRECT: ADDRESS; FROM: 050021 SHIJIAZHUANG, HEBEI PROVINCE TO: 050091 SHIJIAZHUANG, HEBEI PROVINCE

TA01 Transfer of patent application right

Effective date of registration: 20130105

Address after: 050091 Hebei high tech District of Shijiazhuang City Xinshi North Road, No. 86

Applicant after: Hebei Electric Power Construction & Adjustment Research Institute

Applicant after: State Grid Corporation of China

Applicant after: Electric Power Research Institute of Hebei Electric Power Corporation

Address before: 050021 No. 238 South Sports street, Hebei, Shijiazhuang

Applicant before: Hebei Electric Power Construction & Adjustment Research Institute

C14 Grant of patent or utility model
GR01 Patent grant