CN214456840U - CO conversion device for producing hydrogen by gasifying coal water slurry - Google Patents

CO conversion device for producing hydrogen by gasifying coal water slurry Download PDF

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CN214456840U
CN214456840U CN202022764421.5U CN202022764421U CN214456840U CN 214456840 U CN214456840 U CN 214456840U CN 202022764421 U CN202022764421 U CN 202022764421U CN 214456840 U CN214456840 U CN 214456840U
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gas
shift
medium
shift converter
liquid separator
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兰荣亮
汪根宝
马炯
谢东升
王靓
蒋燕
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Sinopec Engineering Group Co Ltd
Sinopec Nanjing Engineering Co Ltd
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Sinopec Engineering Group Co Ltd
Sinopec Nanjing Engineering Co Ltd
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    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30Hydrogen technology
    • Y02E60/36Hydrogen production from non-carbon containing sources, e.g. by water electrolysis

Abstract

The utility model belongs to the technical field of coal chemical plant CO transform technology, and relates to a coal water slurry gasification hydrogen production CO transform device. And optimizing and building a process flow by combining the component characteristics of the crude synthesis gas from the coal water slurry gasification unit and utilizing an integrated design principle. The three-stage adiabatic shift process technology is adopted to meet the CO deep shift requirement of the coal hydrogen production device, in the process optimization design, the medium-pressure boiler feed water is preheated by two stages and then the byproduct steam is removed, a large amount of high-grade steam is obtained, the system heat exchange network is highly integrated, the process production requirement is met, the good energy utilization effect is obtained, the construction investment is saved, and the good operation benefit is obtained.

Description

CO conversion device for producing hydrogen by gasifying coal water slurry
Technical Field
The utility model belongs to the technical field of coal chemical plant CO transform technology, and relates to a coal water slurry gasification hydrogen production CO transform device.
Background
The coal hydrogen production is widely applied to the fields of coal-based chemicals, petroleum refining hydrogenation and the like, and occupies a leading position in hydrogen production in China. The coal hydrogen production device generally comprises units such as coal gasification, CO conversion (conversion for short), acid gas removal, hydrogen purification and the like. The coal gasification technology has many types and can be divided into different types such as coal water slurry gasification, pulverized coal gasification, crushed coal moving bed gasification, fluidized bed gasification and the like. Wherein, the coal water slurry gasification technology is a technology which is more suitable for the project of producing hydrogen from coal in an oil refinery. The most representative coal water slurry gasification technologies include the American GE coal water slurry pressure gasification technology, the two-stage coal water slurry gasification technology developed by Taoism chemical company, and the multi-nozzle coal water slurry gasification technology independently developed by China
The carbon monoxide conversion unit is used as the key technology of the main matching of the coal water slurry gasification hydrogen production device, and CO in the raw gas is converted into H through conversion reaction under the action of a catalyst2. The key equipment of the carbon monoxide shift unit is the shift converter, which is divided by the removal of the shift reaction heat, and the carbon monoxide shift technology can be divided into adiabatic shift and isothermal shift. The adiabatic shift is realized by arranging heat exchangers among 2 shift converters and removing reaction heat outside a reactor. Isothermal shift conversion is to arrange a heat exchange tube bundle in a shift converter and remove reaction heat in a byproduct steam mode. In the coal-to-hydrogen plant,the carbon monoxide isothermal transformation technology mainly has the following defects: (1) the equipment structure of the shift converter is complex, and the cost of single equipment is high; (2) the thermal stress between the heat exchange tube and the tube plate is difficult to eliminate, so that the leakage is easy to occur in the operation process of the equipment; (3) the steam which is a byproduct of isothermal transformation is usually saturated steam, and a steam superheater is additionally arranged to obtain superheated steam, so that the requirement of pipe network transportation is met; (4) the operation stability of the isothermal conversion furnace of the large-scale coal chemical device still needs to be verified for a long period.
Therefore, most of the carbon monoxide shift reaction in the current industrial production adopts a series process of multi-stage adiabatic reactors, thereby meeting the requirement of deep conversion of carbon monoxide in process gas. For a coal hydrogen production device, three shift converters are generally required to be arranged in series to meet the requirement of deep shift rate, and the high-efficiency utilization and recovery of reaction heat directly determine the energy efficiency of the coal hydrogen production device as the carbon monoxide shift reaction is a strong exothermic reaction process. In the coal hydrogen production device which is operated at home at present, part of devices adopt a carbon monoxide adiabatic transformation process, and the following defects mainly exist: a large amount of steam needs to be supplemented by the crude synthesis gas, the heat integration level of the system is not high, the amount of byproduct steam is less, the consumption of circulating water is high, the load of a condensate stripping system is large, and the like.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a weak point to prior art exists, and provide a coal slurry gasification hydrogen manufacturing CO conversion equipment, the process flow design has the operation stably, and system energy integration is effectual, and the high-grade steam volume of byproduct is big advantage such as.
The purpose of the utility model can be realized by the following technical scheme:
a CO conversion device for producing hydrogen by gasifying coal water slurry comprises a detoxification tank, a 1# conversion furnace, a 2# conversion furnace (7) and a 3# conversion furnace; the output pipeline of the crude synthesis gas is connected with a No. 1 gas-liquid separator, and the output end of the crude synthesis gas at the top of the No. 1 gas-liquid separator is sequentially connected with a feed gas steam heater, a detoxification tank and a No. 1 shift converter through pipelines;
the 1# shift converter export links to each other with feed gas steam heater, medium pressure steam generator, 2# middling pressure boiler feedwater preheater, 2# shift converter, low pressure steam superheater, well low pressure steam generator and 3# shift converter in proper order through the pipeline, 3# shift converter export links to each other with 1# middling pressure boiler feedwater preheater, low pressure steam generator and 2# vapour and liquid separator in proper order through the pipeline, and the transform gas at 2# vapour and liquid separator top is carried to waste heat recovery system.
In the above system: and the medium-pressure boiler feed water output pipeline from outside is sequentially connected with the No. 1 medium-pressure boiler feed water preheater, the No. 2 medium-pressure boiler feed water preheater, the medium-pressure steam generator and the feed gas steam heater.
In the above system: the internal part type of the No. 1 gas-liquid separator adopts a vane type or centrifugal tube bundle type high-efficiency separation structure or a wire mesh demister structure.
A method for realizing CO conversion of coal water slurry gasification hydrogen production by using the device comprises the following steps:
1) after the crude synthesis gas enters a No. 1 gas-liquid separator for gas-liquid separation, the top crude synthesis gas passes through a feed gas steam heater for temperature rise, then passes through a detoxification tank, enters a No. 1 shift converter for carbon monoxide shift reaction, after the temperature of the shift gas at the outlet of the No. 1 shift converter rises, is cooled by the feed gas steam heater, then enters a medium pressure steam generator for generating byproduct medium pressure saturated steam, the shift gas is further cooled, and then enters a No. 2 shift converter for continuous carbon monoxide shift reaction through a No. 2 medium pressure boiler feed water preheater;
2) after the temperature of the shift converter outlet of the No. 2 shift converter rises, the shift converter outlet enters a medium-low pressure steam generator through a low-pressure steam superheater to generate medium-low pressure saturated steam as a byproduct, and the shift converter outlet is cooled and then enters a No. 3 shift converter to continue to generate a carbon monoxide deep shift reaction;
3) and the 3# shift converter outlet shift gas sequentially passes through a 1# medium-pressure boiler feed water preheater, a low-pressure steam generator and a 2# gas-liquid separator and then is sent to a heat recovery system.
The method comprises the following steps: the inlet temperature of the # shift converter is controlled to be 260-300 ℃, the outlet temperature of the # 1 shift converter is controlled to be 410-435 ℃, and the conversion rate of the # 1 shift converter is 82-85%.
The method comprises the following steps: the inlet temperature of the 2# shift converter is controlled to be 220-250 ℃, the outlet temperature of the 2# shift converter is controlled to be 250-270 ℃, and the shift rate of the 2# shift converter is 80-85%.
The method comprises the following steps: the inlet temperature of the 3# shift converter is controlled to be 205-220 ℃, the outlet temperature of the 3# shift converter is controlled to be 210-225 ℃, and the shift rate of the 3# shift converter is 57-70%.
The utility model has the advantages that:
the CO conversion device and the CO conversion method for the coal water slurry gasification hydrogen production device are provided, and the process flow is optimized and established by utilizing the integrated design principle of energy and from the component characteristics of the crude synthesis gas of the coal water slurry gasification unit. The three-stage adiabatic shift process technology is adopted to meet the CO deep shift requirement of the coal hydrogen production device, in the process optimization design, the medium-pressure boiler feed water is preheated by two stages and then the byproduct steam is removed, a large amount of high-grade steam is obtained, the system heat exchange network is highly integrated, the process production requirement is met, the good energy utilization effect is obtained, the construction investment is saved, and the good operation benefit is obtained.
Drawings
Fig. 1 is a schematic view of the process of the present invention.
In the figure: the system comprises a 1-1# gas-liquid separator, a 2-raw gas steam heater, a 3-detoxification tank, a 4-1# shift converter, a 5-medium pressure steam generator, a 6-2# high pressure boiler feed water preheater, a 7-2# shift converter, an 8-low pressure steam superheater, a 9-medium and low pressure steam generator, a 10-3# shift converter, a 11-1# high pressure boiler feed water preheater, a 12-low pressure steam generator and a 13-2# gas-liquid separator.
Detailed Description
The present invention will be further explained with reference to the following embodiments, but the scope of the present invention is not limited thereto:
a CO conversion device for producing hydrogen by gasifying coal water slurry comprises a detoxification tank 3, a No. 1 shift converter 4, a No. 2 shift converter 7 and a No. 3 shift converter 10; the output pipeline of the crude synthesis gas is connected with a No. 1 gas-liquid separator 1, and the output end of the crude synthesis gas at the top of the No. 1 gas-liquid separator 1 is sequentially connected with a feed gas steam heater 2, a detoxification tank 3 and a No. 1 shift converter 4 through pipelines;
4 exports of 1# shift converter pass through the pipeline and link to each other with feed gas steam heater 2, medium pressure steam generator 5, 2# medium pressure boiler feedwater preheater 6, 2# shift converter 7, low pressure steam superheater 8, medium and low pressure steam generator 9 and 3# shift converter 10 in proper order, 10 exports of 3# shift converter pass through the pipeline and link to each other with 1# medium pressure boiler feedwater preheater 11, low pressure steam generator 12 and 2# vapour and liquid separator 13 in proper order, and the transform gas at 13 tops of 2# vapour and liquid separator is carried to heat recovery system.
And the medium-pressure boiler feed water output pipeline from the outside is sequentially connected with a 1# medium-pressure boiler feed water preheater 11, a 2# medium-pressure boiler feed water preheater 6, a medium-pressure steam generator 5 and a feed gas steam heater 2.
The internal part type of the No. 1 gas-liquid separator 1 adopts a vane type or centrifugal tube bundle type high-efficiency separation structure or a wire mesh demister structure.
Example 1
The raw synthesis gas from the upstream coal water slurry gasification unit has the flow of 278623kg/h, the CO content of 18.2 percent (wet basis), the temperature of 216 ℃, the pressure of 3.79MPa and the water-gas ratio of 1.41, after gas-liquid separation by a No. 1 gas-liquid separator, the top crude synthesis gas is heated to 260 ℃ by a feed gas steam heater, enters a 1# shift converter to generate a carbon monoxide shift reaction after passing through a detoxification tank, the inlet temperature of the 1# shift converter is 260 ℃, the CO content at the outlet of the 1# shift converter is 2.7% (wet basis), the shift rate is 85%, the temperature of the 1# shift converter outlet is raised to 410 ℃, is cooled to 350 ℃ by the feed gas steam heater, enters a medium-pressure steam generator to generate 28406kg/h medium-pressure saturated steam (the temperature is 254 ℃, the pressure is 4.3MPa), the shift gas is further cooled to 250 ℃, is cooled by a 2# medium-pressure boiler feed water preheater, enters a 2# shift converter to continuously generate the carbon monoxide shift reaction; the inlet temperature of the 2# shift converter is 220 ℃, the CO content at the outlet of the 2# shift converter is 0.5 percent (wet basis) conversion rate is 80 percent, the temperature of the 2# shift converter at the outlet is increased to 250 ℃, the shift gas passes through a low-pressure steam superheater and then enters a medium-low pressure steam generator to produce 6354kg/h of medium-low pressure saturated steam (the temperature is 200 ℃, the pressure is 1.6MPa), and the shift gas is cooled to 210 ℃ and then enters a 3# shift converter to continue to generate a carbon monoxide deep shift reaction; the inlet temperature of the 3# shift converter is 215 ℃, the CO content of the outlet of the 3# shift converter is 0.2 percent (wet basis), the shift rate is 67 percent, and the temperature of the outlet shift gas of the 3# shift converter is increased to 215 ℃, then the temperature sequentially passes through a 1# medium-pressure boiler feed water preheater, a low-pressure steam generator and a 2# gas-liquid separator and then is sent to a heat recovery system.
Example 2
The raw synthesis gas from the upstream coal water slurry gasification unit has the flow of 278623kg/h, the CO content of 18.2 percent (wet basis), the temperature of 216 ℃, the pressure of 3.79MPa and the water-gas ratio of 1.41, after gas-liquid separation by a No. 1 gas-liquid separator, the top crude synthesis gas is heated to 280 ℃ by a feed gas steam heater, enters a 1# shift converter to generate a carbon monoxide shift reaction after passing through a detoxification tank, the inlet temperature of the 1# shift converter is 280 ℃, the CO content at the outlet of the 1# shift converter is 2.8% (wet basis), the shift rate is 84%, the temperature of the shift gas at the outlet of the 1# shift converter is raised to 430 ℃, the top crude synthesis gas is cooled to 365 ℃ by the feed gas steam heater, enters a medium-pressure steam generator to generate 29208kg/h medium-pressure saturated steam (the temperature is 254 ℃, the pressure is 4.3MPa), the shift gas is further cooled to 245 ℃, and enters a 2# shift converter to continuously generate the carbon monoxide shift reaction after being cooled by a feed water preheater of the 2# medium-pressure boiler; the inlet temperature of the 2# shift converter is 238 ℃, the CO content at the outlet of the 2# shift converter is 0.4 percent (wet basis) shift rate is 85 percent, the temperature of the 2# shift converter at the outlet is increased to 260 ℃, the shift gas passes through a low-pressure steam superheater and then enters a medium-low pressure steam generator to produce 7812kg/h of medium-low pressure saturated steam (the temperature is 200 ℃ and the pressure is 1.6MPa), the shift gas is cooled to 220 ℃ and then enters a 3# shift converter to continue to generate carbon monoxide deep shift reaction; the inlet temperature of the 3# shift converter is 220 ℃, the CO content of the outlet of the 3# shift converter is 0.2% (wet basis), the shift rate is 57%, and the temperature of the outlet shift gas of the 3# shift converter is raised to 225 ℃, and then the gas passes through a 1# medium-pressure boiler feed water preheater, a low-pressure steam generator and a 2# gas-liquid separator in sequence and then is sent to a heat recovery system.
Example 3
The raw synthesis gas from the upstream coal water slurry gasification unit has the flow of 278623kg/h, the CO content of 18.2 percent (wet basis), the temperature of 216 ℃, the pressure of 3.79MPa and the water-gas ratio of 1.41, after gas-liquid separation by a No. 1 gas-liquid separator, the top crude synthesis gas is heated to 300 ℃ by a feed gas steam heater, then enters a No. 1 shift converter through a detoxification tank to generate a carbon monoxide shift reaction, the inlet temperature of the No. 1 shift converter is 300 ℃, the CO content at the outlet of the No. 1 shift converter is 3.2% (wet basis), the shift rate is 82%, the temperature of the change gas at the outlet of the No. 1 shift converter is raised to 435 ℃, the raw gas is cooled to 370 ℃ by the feed gas steam heater, then enters a medium-pressure steam generator to generate 30103kg/h of medium-pressure saturated steam (the temperature is 254 ℃, the pressure is 4.3MPa), the shift gas is further cooled to 255 ℃, and the raw gas enters a No. 2 shift converter to continuously generate the carbon monoxide shift reaction after being cooled by a feed water preheater of the No. 2 medium-pressure boiler; the inlet temperature of the 2# shift converter is 250 ℃, the CO content at the outlet of the 2# shift converter is 0.6 percent (wet basis) shift rate is 81 percent, the temperature of the shift gas at the outlet of the 2# shift converter is increased to 270 ℃, the shift gas passes through a low-pressure steam superheater and enters a medium-low pressure steam generator to produce 8765kg/h of medium-low pressure saturated steam (the temperature is 200 ℃ and the pressure is 1.6MPa), the shift gas is cooled to 205 ℃ and then enters a 3# shift converter to continue to generate carbon monoxide deep shift reaction; the inlet temperature of the 3# shift converter is 205 ℃, the CO content of the outlet of the 3# shift converter is 0.2 percent (wet basis), the shift rate is 70 percent, and the temperature of the outlet shift gas of the 3# shift converter is raised to 210 ℃, and then the temperature is sent to a heat recovery system after passing through a 1# medium-pressure boiler feed water preheater, a low-pressure steam generator and a 2# gas-liquid separator in sequence.
The foregoing embodiments and description only illustrate the principles of the present invention and do not limit the scope of the invention, and the present invention will be further modified without departing from the spirit and scope of the invention, which falls within the scope of the invention as claimed. The utility model discloses the part that does not relate to all is the same with prior art or can adopt prior art to realize.

Claims (3)

1. A CO conversion device for producing hydrogen by gasifying coal water slurry is characterized in that: the device comprises a detoxification tank (3), a 1# conversion furnace (4), a 2# conversion furnace (7) and a 3# conversion furnace (10); the output pipeline of the crude synthesis gas is connected with a No. 1 gas-liquid separator (1), and the output end of the crude synthesis gas at the top of the No. 1 gas-liquid separator (1) is sequentially connected with a feed gas steam heater (2), a detoxification groove (3) and a No. 1 shift converter (4) through pipelines;
the export of 1# shift converter (4) links to each other with feed gas steam heater (2), medium pressure steam generator (5), 2# medium pressure boiler feedwater preheater (6), 2# shift converter (7), low pressure steam superheater (8), well low pressure steam generator (9) and 3# shift converter (10) in proper order through the pipeline, 3# shift converter (10) export links to each other with 1# medium pressure boiler feedwater preheater (11), low pressure steam generator (12) and 2# vapour and liquid separator (13) in proper order through the pipeline, and the transform gas at 2# vapour and liquid separator (13) top is carried to waste heat recovery system.
2. The CO shift device for producing hydrogen by gasifying coal water slurry according to claim 1, characterized in that: the medium-pressure boiler feed water output pipeline from the outside is sequentially connected with a 1# medium-pressure boiler feed water preheater (11), a 2# medium-pressure boiler feed water preheater (6), a medium-pressure steam generator (5) and a feed gas steam heater (2).
3. The CO shift device for producing hydrogen by gasifying coal water slurry according to claim 1, characterized in that: the internal part type of the No. 1 gas-liquid separator (1) adopts a vane type or centrifugal tube bundle type high-efficiency separation structure or a wire mesh demister structure.
CN202022764421.5U 2020-11-25 2020-11-25 CO conversion device for producing hydrogen by gasifying coal water slurry Active CN214456840U (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112456439A (en) * 2020-11-25 2021-03-09 中石化南京工程有限公司 CO conversion device and method for producing hydrogen by gasifying coal water slurry

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112456439A (en) * 2020-11-25 2021-03-09 中石化南京工程有限公司 CO conversion device and method for producing hydrogen by gasifying coal water slurry

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