CN204337961U - Liquid steel refining dry vacuum system electricity consumption-bag complex filter - Google Patents

Liquid steel refining dry vacuum system electricity consumption-bag complex filter Download PDF

Info

Publication number
CN204337961U
CN204337961U CN201420810522.3U CN201420810522U CN204337961U CN 204337961 U CN204337961 U CN 204337961U CN 201420810522 U CN201420810522 U CN 201420810522U CN 204337961 U CN204337961 U CN 204337961U
Authority
CN
China
Prior art keywords
bag
dust
flue
filter
filtration
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
CN201420810522.3U
Other languages
Chinese (zh)
Inventor
何秀明
张佩
雷波
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.)
Co Ltd Of Design Inst Chongqing Iron & Steel Group
Original Assignee
Co Ltd Of Design Inst Chongqing Iron & Steel Group
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 Co Ltd Of Design Inst Chongqing Iron & Steel Group filed Critical Co Ltd Of Design Inst Chongqing Iron & Steel Group
Priority to CN201420810522.3U priority Critical patent/CN204337961U/en
Application granted granted Critical
Publication of CN204337961U publication Critical patent/CN204337961U/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Abstract

The utility model discloses a kind of liquid steel refining dry vacuum system electricity consumption-bag complex filter, comprise electric filtration barrel body and bag filtration cylindrical shell, described electric filtration barrel body and bag filtration cylinder body bottom correspondence are provided with flue-dust retainer, top correspondence is provided with gas feed and gas vent, is provided with the communicating pipe be connected by two cylindrical shells above two flue-dust retainers; Described electric filtration barrel body center is provided with electrostatic filter device, and described bag filtration cylindrical shell center is provided with bag type filter device; Described gas feed is arranged on above electrostatic filter device, and described gas vent is arranged on above bag type filter device; This device realizes first order dedusting by electrostatic filter device, the part dust in dusty gas can be removed, and flue-gas temperature is obviously reduced, dusty gas after primary dust removing is again through bag type filter device, realize second level dedusting, not only good dedusting effect, also effectively reduces the live load of filter bag and dust granules to the souring of filter bag, extends cleaning cycle and life of bag filter.

Description

Liquid steel refining dry vacuum system electricity consumption-bag complex filter
Technical field
The utility model belongs to liquid steel refining dry vacuum system art of filters, is specifically related to a kind of liquid steel refining dry vacuum system electricity consumption-bag complex filter.
Background technology
In field of metallurgy, dry vacuum system is the emerging application of one in molten steel furnace external refining, and it adopts dry-type mechanical pump to substitute traditional wet type steam jet pump as pumping equipment.Molten steel is carried out in the process of the outer vacuum refining of stove; the a large amount of dust produced from molten steel can enter vacuum pipe along with process gas; for the oil-sealed rotary pump in protection dry vacuum system, need filter be set before oil-sealed rotary pump process gas is purified.
The process gas composition of liquid steel refining is more complicated, and containing hydrogen, oxygen, nitrogen, argon gas, carbon monoxide, carbon dioxide etc., particularly in molten steel decarbonizing process, carbon monoxide content is higher, once leakage can cause personnel poisoning or produce blast danger.And flue dust grit temperature in process gas is higher, its main component is manganese oxide, iron oxide and other metal oxides (Al, Zn, K, Na, Pb etc.), and flue dust particle diameter is 0.4 μm ~ 100+ μm, meets air and there will be spontaneous combustion and Mars phenomenon.
Traditional typical filter device form has electrostatic filter and bag filter etc.
Electrostatic filter utilizes electrostatic force to remove dust granules from process gas, and it is primarily of compositions such as body, DC high-voltage power supply, deashing devices.Metal dust collecting electrode (positive plate) that be arranged with One's name is legion in body, that keep a determining deviation and corona discharge electrode (cathode line), in order to produce corona, trapping dust.The advantage of electrostatic filter: efficiency of dust collection is high, can reach about 99% (many electric fields); Bulk density loss is little, and under normal pressure, (or tiny structure) is generally 160 ~ 300Pa; Energy consumption is low, and process 1000m3/h flue gas about needs 0.2 ~ 0.6kWh; Smoke treatment amount is large; Heat resistance is good, generally can work at 350 ~ 400 DEG C.But its shortcoming also clearly, and main manifestations is: complex structure, steel consume many, and one-time investment is high; Making and installation required precision is high; Responsive to Dust Characteristics, optimum dust specific resistance scope 104 ~ 5 × 1010 Ω cm, if outside this scope, even if adopt the electric field of more than 4, its concentration of emission also cannot reach below 100mg/m3.
Traditional bag filter is a kind of cleaner utilizing the bag-like filter element of porous (filtrate) to collect dust from dusty gas, primarily of filter and deashing device composition.When dusty gas is by filtrate, main rely on filter media fibre sieving, interception, collision, diffusion and electrostatic attraction effect, by dust detention on filtrate.When the dust of filter bag surface sediment reaches certain thickness, the pressure loss of equipment increases, disposal ability reduces, and must carry out deashing, to ensure the gas permeability needed for filter bag continuous firing by deashing device to filter bag.Relative to electrostatic filter, the shortcoming of bag filter: be not suitable for running work at high operating temperatures, Long-term service temperature is no more than 200 DEG C, the limit of working temperature is no more than 260 DEG C (in short-term); Drag losses is comparatively large, and under normal pressure, (or tiny structure) is generally 800 ~ 1200Pa.
The casing of conventional electrostatic formula and bag filter is generally square, when working under negative pressure, often produce the situation that wallboard caves in due to housing insufficient rigidity, the wallboard resilience when system is pressed again, make equipment produce the larger sound and vibrations, the security of operation of equipment time serious, can be affected.
Conventional electrostatic formula and bag filter all allow certain leakage rate (air leak rate of air curtain), but in liquid steel refining dry vacuum system, due to the impact of smoke components and Dust Characteristics, once enter air in systems in which, not only reduce the vacuum of system, affect the effect of liquid steel refining, and dust spontaneous combustion, scaling loss filter bag can be made, make dust granules be entered oil-sealed rotary pump, damage is caused to vavuum pump.
Summary of the invention
In view of this, the purpose of this utility model is to provide that a kind of structure is simple, good filtration effect, can bears the liquid steel refining dry vacuum system electricity consumption-bag complex filter of larger negative pressure and explosion-proof performance.。
For achieving the above object, the utility model provides following technical scheme: a kind of liquid steel refining dry vacuum system electricity consumption-bag complex filter, comprise electric filtration barrel body and bag filtration cylindrical shell, described electric filtration barrel body and bag filtration cylinder body bottom correspondence are provided with flue-dust retainer, top correspondence is provided with gas feed and gas vent, is provided with the communicating pipe be connected by two cylindrical shells above two flue-dust retainers; Described electric filtration barrel body center is provided with electrostatic filter device, and described bag filtration cylindrical shell center is provided with bag type filter device; Described gas feed is arranged on above electrostatic filter device, and described gas vent is arranged on above bag type filter device.
Further, also comprise self sealss automatic pressure releasing mechanism, urgent nitrogen fill valve, ash-discharging device and PLC control system, described self sealss automatic pressure releasing mechanism correspondence is arranged on the top of electric filtration barrel body and bag filtration cylindrical shell, described urgent nitrogen fill valve is arranged on the top of bag filtration cylindrical shell, and described ash-discharging device correspondence is arranged on bottom flue-dust retainer.
Further, described electrostatic filter device comprises air distribution plate I, is arranged on the DC high-voltage power supply on electric filtration barrel body sidewall, the positive plate be crisscross arranged and cathode line, for the anode vibration body of vibration dust-cleaning and cathode rapping mechanism, control anode rapping transmission and the cathode rapping transmission of vibration body for correspondence, described air distribution plate I is arranged on above positive plate and cathode line.
Further, described bag type filter device comprises card, filter bag, cage, air distribution plate II and deashing device, and described card is fixed on bag filtration cylindrical shell, and described filter bag and cage are arranged on card, and described air distribution plate II is arranged on below filter bag and cage; Described deashing device is primarily of Venturi tube and blowing device composition, and described Venturi tube is arranged on cage upper end, and described blowing device is arranged on above Venturi tube.
Further, also comprise flow apron, described flow apron is arranged on communicating pipe, and flue-dust retainer lower center place bottom electric filtration barrel body is partial in the direction of blocking of flow apron.
Further, described flue-dust retainer is provided with rapping apparatus; Gear ash-pan is provided with in flue-dust retainer.
The beneficial effects of the utility model are:
1. this device sets advantage of electrostatic filter and bag filter, first order dedusting is realized by electrostatic filter device, the part dust in dusty gas can be removed, and flue-gas temperature is obviously reduced, dusty gas after primary dust removing, again through bag type filter device, realizes second level dedusting, not only good dedusting effect, also effectively reduce the live load of filter bag and dust granules to the souring of filter bag, extend cleaning cycle and life of bag filter;
2. adopt vacuum system container self sealss automatic pressure releasing mechanism, effectively can prevent that equipment internal gas pressure is too high causes the security incidents such as blast, and can effective sealing under vacuo, enhance the safety and reliability of equipment;
3. automaticity is high, and each several part, by PLC system Real-Time Monitoring, is not only easy to control, more improves the safety and reliability of equipment, decrease staffing, saved cost input.
Accompanying drawing explanation
In order to make the purpose of this utility model, technical scheme and beneficial effect clearly, the utility model provides following accompanying drawing to be described:
Fig. 1 is structural representation of the present utility model;
Fig. 2 is A-A sectional view in Fig. 1;
Fig. 3 is B-B sectional view in Fig. 1.
Detailed description of the invention
Below in conjunction with accompanying drawing, preferred embodiment of the present utility model is described in detail.
As shown in the figure, liquid steel refining dry vacuum system electricity consumption-bag complex filter in the present embodiment, comprise electric filtration barrel body 1 and bag filtration cylindrical shell 2, bottom described electric filtration barrel body 1 and bag filtration cylindrical shell 2, correspondence is provided with flue-dust retainer 3, top correspondence is provided with above gas feed 4 and gas vent 5, two flue-dust retainer 3 and is provided with the communicating pipe 6 be connected by two cylindrical shells; Described electric filtration barrel body 1 center is provided with electrostatic filter device, and described bag filtration cylindrical shell 2 center is provided with bag type filter device; Described gas feed 4 is arranged on above electrostatic filter device, and described gas vent 5 is arranged on above bag type filter device.
Also comprise in the present embodiment and also comprise self sealss automatic pressure releasing mechanism 7, urgent nitrogen fill valve 8, ash-discharging device and PLC control system 9, described self sealss automatic pressure releasing mechanism 7 correspondence is arranged on the top of electric filtration barrel body 1 and bag filtration cylindrical shell 2, described urgent nitrogen fill valve 8 is arranged on the top of bag filtration cylindrical shell 2, and described ash-discharging device correspondence is arranged on bottom flue-dust retainer 3.
Concrete, electrostatic filter device in the present embodiment comprises air distribution plate I 10, the DC high-voltage power supply 11 be arranged on electric filtration barrel body 1 sidewall, the positive plate 12 that is crisscross arranged and cathode line 13, anode vibration body 14 and cathode rapping mechanism 15 for vibration dust-cleaning, control anode rapping transmission 16 and the cathode rapping transmission 17 of vibration body for correspondence, described air distribution plate I 10 is arranged on above positive plate 12 and cathode line 13.
Bag type filter device in the present embodiment comprises card 18, filter bag 19, cage 20, air distribution plate II 21 and deashing device, described card 18 is fixed on bag filtration cylindrical shell 2, described filter bag 19 and cage 20 are arranged on card 18, and described air distribution plate II 21 is arranged on below filter bag 19 and cage 20; Described deashing device forms primarily of Venturi tube 22 and blowing device 23, and described Venturi tube 22 is arranged on cage 20 upper end, and described blowing device 23 is arranged on above Venturi tube 22.
In the present embodiment, electrostatic filter device and bag type filter device are separately positioned on the middle part of electric filtration barrel body 1 and bag filtration cylindrical shell 2, electricity filtration barrel body 1 and each self-forming in bag filtration cylindrical shell 2 top one have the cavity of a constant volume, and this cavity is the inlet plenum 24 of side, electric district and the discharge chamber 25 of side, bag district.After dusty gas enters inlet plenum 24 from gas feed 4, after being uniformly distributed of air distribution plate I 10, enter the electric field region between multiple positive plate 12 from top to bottom; Under the effect of high electric-field intensity, gas ionization produces a large amount of electric charge, when gas is by electric field, electric charge is attached on dust granules, makes dust charged, under the effect of electric field force, Charged shifts to positive plate 12 (dust collecting electrode), realizes first order dedusting.
When dusty gas arrives bottom electric field region, enter bag type filter device through communicating pipe 6.In dusty gas uphill process, first by air distribution plate II 21, then enter a bag district uniformly.Under the effect of the sieving of filter bag 19, interception, collision, diffusion and electrostatic attraction, realize second level dedusting.The grit detention of dusty gas is on filter bag 19, and last clean gas enters in discharge chamber 25, discharges from gas vent 5.
Through the first order dust removal process in electric district, the part dust in dusty gas can be removed, and flue-gas temperature is obviously reduced (in process gas, contained high temperature grit carries amount of heat), thus effectively reduce the live load of filter bag 19 and dust granules to the souring of filter bag 19, effectively increase cleaning cycle and life-span of the filter bag.
In the present embodiment, self sealss automatic pressure releasing mechanism 7 adopts vacuum system container self sealss automatic pressure releasing mechanism, effectively can prevent that equipment internal gas pressure is too high causes the security incidents such as blast, and can effective sealing under vacuo, enhances the safety and reliability of equipment.Ash-discharging device comprises discharge valve 26 and vacuum isolating valve 27, and described vacuum isolating valve 27 is arranged between discharge valve 26 and flue-dust retainer 3; Vacuum isolating valve 27 ensures equipment positiver sealing unload ash uniformly under condition under vacuo, prevents from, because air enters a bag district when unloading ash, causing the dust spontaneous combustion of accumulation on filter bag 19 simultaneously, thus scaling loss filter bag 19.PLC system comprises material-level detection system 28, system for detecting temperature (grey side thermometer 29, bag side thermometer 30) and differential pressure measuring system 31; Wherein, described material-level detection system 28 can the ash quantity of measuring set ash bucket 3, and described system for detecting temperature can measure the temperature of bag side and grey side, and described differential pressure measuring system 31 can measure pressure reduction before and after filter bag 19.
Be provided with independently electric filtration barrel body 1, bag filtration cylindrical shell 2 and flue-dust retainer 3, two in the present embodiment to be connected by communicating pipe 6 between cylindrical shell; Two cylindrical shells are cylindrical, flue-dust retainer 3 and are inversed taper platform shape, and electric filtration barrel body 1, bag filtration cylindrical shell 2 and flue-dust retainer 3 outer wall place are equipped with reinforcement, can guarantee that apparatus casing is indeformable under high vacuum environment.
In the present embodiment, be equipped with deashing device in bag type filter device, deashing device forms primarily of Venturi tube 22 and blowing device 23; Wherein, blowing device 23 comprises correspondence and is arranged on some injection tubes 32 above filter bag 19 and nozzle 33, each injection tube 32 is connected with winding-up collector 34, the corresponding pulse valve 35 be provided with for controlling each injection tube 32 flow on winding-up collector 34, and pulse valve 35 is controlled by PLC system 9; This deashing device can realize timing deashing or utilize pressure differential detection result to determine deashing opportunity, and automaticity is high, is easy to control.
As the further improvement of such scheme, also comprise flow apron 36 in the present embodiment, described flow apron 36 is arranged on communicating pipe 6, and flue-dust retainer 3 lower center place bottom electric filtration barrel body 1 is partial in the direction of blocking of flow apron 36.
Further, described flue-dust retainer is provided with rapping apparatus; Gear ash-pan is provided with in flue-dust retainer.Supporting steel frame, in order to supporting filter equipment, and facilitates equipment routing inspection and unloads ash; The dustiness of the gas of communicating pipe 6 can be decreased through, improve fume recovery rate.
In the present embodiment, for ease of deashing, flue-dust retainer 3 is provided with rapping apparatus 37, meanwhile, is also provided with gear ash-pan 38, to reduce the reentrainment of dust caused due to gas shock in flue-dust retainer 3.
In the present embodiment, the negative electrode of electrostatic filter device shakes transmission 17, anode shakes transmission 16 and adopts vacuum seal axle sleeve 39 to be connected with electric filtration barrel body 1 junction, guarantees No leakage under vaccum working condition.
In the present embodiment, electric filtration barrel body 1 and bag filtration cylindrical shell 2 are arranged on support 40.
What finally illustrate is, above preferred embodiment is only in order to illustrate the technical solution of the utility model and unrestricted, although be described in detail the utility model by above preferred embodiment, but those skilled in the art are to be understood that, various change can be made to it in the form and details, and not depart from the utility model claims limited range.

Claims (6)

1. liquid steel refining dry vacuum system electricity consumption-bag complex filter, it is characterized in that: comprise electric filtration barrel body and bag filtration cylindrical shell, described electric filtration barrel body and bag filtration cylinder body bottom correspondence are provided with flue-dust retainer, top correspondence is provided with gas feed and gas vent, is provided with the communicating pipe be connected by two cylindrical shells above two flue-dust retainers; Described electric filtration barrel body center is provided with electrostatic filter device, and described bag filtration cylindrical shell center is provided with bag type filter device; Described gas feed is arranged on above electrostatic filter device, and described gas vent is arranged on above bag type filter device.
2. liquid steel refining dry vacuum system electricity consumption-bag complex filter according to claim 1, it is characterized in that: also comprise self sealss automatic pressure releasing mechanism, urgent nitrogen fill valve, ash-discharging device and PLC control system, described self sealss automatic pressure releasing mechanism correspondence is arranged on the top of electric filtration barrel body and bag filtration cylindrical shell, described urgent nitrogen fill valve is arranged on the top of bag filtration cylindrical shell, and described ash-discharging device correspondence is arranged on bottom flue-dust retainer.
3. liquid steel refining dry vacuum system electricity consumption-bag complex filter according to claim 1, it is characterized in that: described electrostatic filter device comprises air distribution plate I, is arranged on the DC high-voltage power supply on electric filtration barrel body sidewall, the positive plate be crisscross arranged and cathode line, for the anode vibration body of vibration dust-cleaning and cathode rapping mechanism, control anode rapping transmission and the cathode rapping transmission of vibration body for correspondence, described air distribution plate I is arranged on above positive plate and cathode line.
4. liquid steel refining dry vacuum system electricity consumption-bag complex filter according to claim 1, it is characterized in that: described bag type filter device comprises card, filter bag, cage, air distribution plate II and deashing device, described card is fixed on bag filtration cylindrical shell, described filter bag and cage are arranged on card, and described air distribution plate II is arranged on below filter bag and cage; Described deashing device is primarily of Venturi tube and blowing device composition, and described Venturi tube is arranged on cage upper end, and described blowing device is arranged on above Venturi tube.
5. liquid steel refining dry vacuum system electricity consumption-bag complex filter according to claim 1, it is characterized in that: also comprise flow apron, described flow apron is arranged on communicating pipe, and flue-dust retainer lower center place bottom electric filtration barrel body is partial in the direction of blocking of flow apron.
6. liquid steel refining dry vacuum system electricity consumption-bag complex filter according to claim 1, is characterized in that: described flue-dust retainer is provided with rapping apparatus; Gear ash-pan is provided with in flue-dust retainer.
CN201420810522.3U 2014-12-19 2014-12-19 Liquid steel refining dry vacuum system electricity consumption-bag complex filter Active CN204337961U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201420810522.3U CN204337961U (en) 2014-12-19 2014-12-19 Liquid steel refining dry vacuum system electricity consumption-bag complex filter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201420810522.3U CN204337961U (en) 2014-12-19 2014-12-19 Liquid steel refining dry vacuum system electricity consumption-bag complex filter

Publications (1)

Publication Number Publication Date
CN204337961U true CN204337961U (en) 2015-05-20

Family

ID=53221265

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201420810522.3U Active CN204337961U (en) 2014-12-19 2014-12-19 Liquid steel refining dry vacuum system electricity consumption-bag complex filter

Country Status (1)

Country Link
CN (1) CN204337961U (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105727643A (en) * 2016-03-07 2016-07-06 苏州保酚环境科技有限公司 Filter bag dust collector with quick change type filter bag cage shelf combinations
CN106975285A (en) * 2017-05-11 2017-07-25 南通普瑞特机械有限公司 A kind of industrial smoke sack cleaner
CN107520049A (en) * 2017-08-19 2017-12-29 安徽卓煌机械设备有限公司 A kind of multistage combined mesh electrode coal dust dust-precipitator
CN108554088A (en) * 2018-05-07 2018-09-21 李冰霜 A kind of efficient two-stage dust-extraction unit of silicon PU productions
CN113230808A (en) * 2021-06-03 2021-08-10 濮阳职业技术学院 Road dust absorbing device for civil engineering

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105727643A (en) * 2016-03-07 2016-07-06 苏州保酚环境科技有限公司 Filter bag dust collector with quick change type filter bag cage shelf combinations
CN105727643B (en) * 2016-03-07 2018-09-25 苏州保酚环境科技有限公司 A kind of bag dust collector of quick-changing type filter bag cage combination
CN106975285A (en) * 2017-05-11 2017-07-25 南通普瑞特机械有限公司 A kind of industrial smoke sack cleaner
CN107520049A (en) * 2017-08-19 2017-12-29 安徽卓煌机械设备有限公司 A kind of multistage combined mesh electrode coal dust dust-precipitator
CN107520049B (en) * 2017-08-19 2019-06-14 盐城吉达机械设备有限公司 A kind of multistage combined mesh electrode coal dust dust-precipitator
CN108554088A (en) * 2018-05-07 2018-09-21 李冰霜 A kind of efficient two-stage dust-extraction unit of silicon PU productions
CN113230808A (en) * 2021-06-03 2021-08-10 濮阳职业技术学院 Road dust absorbing device for civil engineering

Similar Documents

Publication Publication Date Title
CN204337961U (en) Liquid steel refining dry vacuum system electricity consumption-bag complex filter
CN204337960U (en) Liquid steel refining dry vacuum system whirlwind-cloth bag complex filter
CN203842445U (en) Industrial smoke pipe harmless efficient treatment device
CN204337962U (en) Liquid steel refining dry vacuum system electricity consumption-bag integral filter
CN103736604A (en) Cyclone wet type electrostatic dust collector
CN204684863U (en) A kind of simple liquid absorption type dust arrester
CN208320288U (en) A kind of zinc fume collecting device
CN106178739A (en) A kind of horizontally loaded type hot precipitator
CN101402012A (en) Crystal cotton frameless pulse precipitation apparatus
CN101602951A (en) The side-mounted coke furnace flue gas integration dust-removal process that discharges of the coke of coalingging
CN204411933U (en) A kind of high-effective dust-removing equipment
CN202724958U (en) Pulse bag-type dust collector
CN102071281A (en) Converter gas dry method bag type recovering and purifying system and process
CN204469482U (en) A kind of dust arrester for MOCVD board
CN201404749Y (en) High temperature-resistant dust cleaner
CN208541962U (en) A kind of online dust pelletizing system of converter
CN208599359U (en) A kind of bag filter
CN206304488U (en) A kind of high-effective dust-removing cleaning equipment
CN104911373A (en) Closed heating lead smelting system
CN204874691U (en) Seal and add plumbous system of heat refining
CN202105544U (en) High-temperature resistant dust remover
CN108236816A (en) Using compressed air as the bag-type dust collector and dust removal method of deashing power
CN204799019U (en) Handle negative pressure formula low pressure pulse sack dust collector of boiler flue gas
CN204933181U (en) Automatic temperature-control tier-framework building smoke eliminator
CN204502699U (en) A kind of pulse dust collector

Legal Events

Date Code Title Description
C14 Grant of patent or utility model
GR01 Patent grant