CN112944804A - Method for supplying oxygen and nitrogen with small flow for air separation device - Google Patents
Method for supplying oxygen and nitrogen with small flow for air separation device Download PDFInfo
- Publication number
- CN112944804A CN112944804A CN202110157832.4A CN202110157832A CN112944804A CN 112944804 A CN112944804 A CN 112944804A CN 202110157832 A CN202110157832 A CN 202110157832A CN 112944804 A CN112944804 A CN 112944804A
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- Prior art keywords
- oxygen
- nitrogen
- small
- liquid
- pump
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- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 title claims abstract description 176
- 229910052757 nitrogen Inorganic materials 0.000 title claims abstract description 88
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 title claims abstract description 42
- 239000001301 oxygen Substances 0.000 title claims abstract description 42
- 229910052760 oxygen Inorganic materials 0.000 title claims abstract description 42
- 238000000926 separation method Methods 0.000 title claims abstract description 29
- 238000000034 method Methods 0.000 title claims abstract description 14
- 238000002309 gasification Methods 0.000 claims abstract description 11
- 238000012423 maintenance Methods 0.000 claims abstract description 9
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 55
- 239000007788 liquid Substances 0.000 claims description 51
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 21
- 239000006200 vaporizer Substances 0.000 claims description 19
- 238000009834 vaporization Methods 0.000 claims description 3
- 230000008016 vaporization Effects 0.000 claims description 3
- 230000009466 transformation Effects 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000003245 coal Substances 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000005086 pumping Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 239000008400 supply water Substances 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
- F25J3/04521—Coupling of the air fractionation unit to an air gas-consuming unit, so-called integrated processes
- F25J3/04527—Integration with an oxygen consuming unit, e.g. glass facility, waste incineration or oxygen based processes in general
- F25J3/04539—Integration with an oxygen consuming unit, e.g. glass facility, waste incineration or oxygen based processes in general for the H2/CO synthesis by partial oxidation or oxygen consuming reforming processes of fuels
- F25J3/04545—Integration with an oxygen consuming unit, e.g. glass facility, waste incineration or oxygen based processes in general for the H2/CO synthesis by partial oxidation or oxygen consuming reforming processes of fuels for the gasification of solid or heavy liquid fuels, e.g. integrated gasification combined cycle [IGCC]
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
- C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
- C10J3/46—Gasification of granular or pulverulent flues in suspension
- C10J3/48—Apparatus; Plants
- C10J3/50—Fuel charging devices
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Combustion & Propulsion (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Separation By Low-Temperature Treatments (AREA)
Abstract
The invention discloses a method for supplying oxygen and nitrogen with small flow for an air separation device, which comprises the following steps: supplying oxygen at a small flow rate, and debugging and using a burner of the gasification furnace; the small flow supplies nitrogen for equipment maintenance. The oxygen and nitrogen supply method can provide small flow of oxygen and nitrogen through technical transformation of the existing equipment without starting an air separation device, meets the debugging and shutdown maintenance of the burner of the gasification furnace, saves the great cost and improves the economic benefit.
Description
Technical Field
The invention relates to the technical field of IGCC power stations, in particular to a method for supplying oxygen and nitrogen with small flow rate by an air separation device.
Background
IGCC power plants, i.e., integrated gasification combined cycle power generation systems, are advanced power systems that combine coal gasification technology with efficient combined cycles. Pure oxygen and pulverized coal produced by a cryogenic air separation device are subjected to incomplete combustion reaction in a gasification furnace to generate synthesis gas, the synthesis gas is combusted in a gas turbine to do work to drive a generator, high-temperature gas after combustion enters a waste heat boiler to supply water and heat to generate steam, and the steam turbine does work to drive the generator.
The oxygen and nitrogen yields of the air separation plant of the IGCC power station are all 50000Nm3About/h, the oxygen production can be operated in the range of 75-105% of the designed oxygen production variable load working condition (no air and product emptying). However, the air separation plant cannot supply oxygen and nitrogen in an off-stream state, which results in the need to start up the entire air separation system if the gasification plant needs a small amount of medium-pressure oxygen to debug the burner or a small amount of nitrogen is supplied to each system for nitrogen charging maintenance. The condition of emptying a large amount of oxygen and nitrogen occurs, which causes a large amount of power consumption and improves the production cost.
Disclosure of Invention
In view of the above-mentioned drawbacks and deficiencies of the prior art, it is desirable to provide a method for supplying oxygen and nitrogen at a small flow rate for an air separation plant, which can save a great cost and improve economic efficiency by technically modifying the existing plant without starting the air separation plant.
The invention provides a method for supplying oxygen and nitrogen with small flow for an air separation device, which comprises the following steps:
supplying oxygen at a small flow rate, wherein an external liquid oxygen storage tank is communicated with a liquid oxygen storage tank at the output end of an air separation device, a small-flow liquid oxygen pump is communicated with the liquid oxygen storage tank, a liquid oxygen water bath type vaporizer is arranged at the output end of the small-flow liquid oxygen pump, low-pressure steam is introduced into a water bath of the liquid oxygen water bath type vaporizer to control the temperature of oxygen, the oxygen enters the liquid oxygen water bath type vaporizer to be heated and vaporized after being pressurized by the small-flow liquid oxygen pump, and the vaporized oxygen enters a medium-pressure oxygen pipe network to be used for debugging a burner of a gasification furnace;
and the small-flow liquid nitrogen supply device supplies nitrogen at a small flow rate, an external liquid nitrogen storage tank is communicated with a liquid nitrogen storage tank at the output end of the air separation device, a small-flow liquid nitrogen pump is communicated with the liquid nitrogen storage tank, a liquid nitrogen water bath type vaporizer is arranged at the output end of the small-flow liquid nitrogen pump, and nitrogen enters the liquid nitrogen water bath type vaporizer for vaporization after being pressurized by the small-flow liquid nitrogen pump and then enters a high-pressure nitrogen pipe network for maintenance of gas supply equipment.
Preferably, the small-flow liquid oxygen pump is electrically connected with a first speed change device, and the small-flow liquid nitrogen pump is electrically connected with a second speed change device.
Preferably, a liquid oxygen sending valve is arranged between the liquid oxygen storage tank and the small-flow liquid oxygen pump; and a liquid nitrogen delivery valve is arranged between the liquid nitrogen storage tank and the small-flow liquid nitrogen pump.
Compared with the prior art, the invention has the beneficial effects that:
the method provided by the invention is used for reconstructing a backup system on the basis of the existing air separation plant, and is additionally provided with the small-flow liquid oxygen pump, the small-flow liquid nitrogen pump, the liquid oxygen water bath vaporizer, the liquid nitrogen water bath vaporizer, the related pipeline and the valve, so that the method is a simple and economic way for enabling the backup system of the air separation plant to be safer and more complete, can meet the requirements of small-flow oxygen supply for debugging a burner of a gasification furnace, small-flow nitrogen supply for daily maintenance during the shutdown period of the air separation plant and the like, saves the economic cost, and has the advantages of adjustable margin size and high adjusting speed.
It should be understood that the statements herein reciting aspects are not intended to limit the critical or essential features of any embodiment of the invention, nor are they intended to limit the scope of the invention. Other features of the present invention will become apparent from the following description.
Drawings
Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments made with reference to the following drawings:
FIG. 1 is a flow diagram of small flow oxygen supply;
FIG. 2 is a flow diagram of a small flow nitrogen supply.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not restrictive of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings.
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.
Referring to fig. 1 to fig. 2, an embodiment of the present invention provides a method for generating oxygen and nitrogen with a small flow rate for an air separation plant, including the following steps:
supplying oxygen at a small flow rate, wherein an external liquid oxygen storage tank is communicated with a liquid oxygen storage tank at the output end of an air separation device, a small-flow liquid oxygen pump is communicated with the liquid oxygen storage tank, a liquid oxygen water bath type vaporizer is arranged at the output end of the small-flow liquid oxygen pump, low-pressure steam is introduced into a water bath of the liquid oxygen water bath type vaporizer to control the temperature of oxygen, the oxygen enters the liquid oxygen water bath type vaporizer to be heated and vaporized after being pressurized by the small-flow liquid oxygen pump, and the vaporized oxygen enters a medium-pressure oxygen pipe network and is used for debugging a burner of a gasifier;
and (2) supplying nitrogen at a small flow, namely communicating an external liquid nitrogen storage tank with a liquid nitrogen storage tank at the output end of the air separation device, communicating a small-flow liquid nitrogen pump with the liquid nitrogen storage tank, installing a liquid nitrogen water bath type vaporizer at the output end of the small-flow liquid nitrogen pump, pressurizing the nitrogen by the small-flow liquid nitrogen pump, then feeding the nitrogen into the liquid nitrogen water bath type vaporizer for vaporization, and then feeding the nitrogen into a high-pressure nitrogen pipe network for maintenance of gas supply equipment.
In this embodiment, the method of the present application modifies a backup system on the basis of an existing air separation plant. A small-flow liquid oxygen pump and a liquid oxygen water bath vaporizer are added behind the liquid oxygen storage tank; a small flow liquid nitrogen pump and a liquid nitrogen bath vaporizer are added after the liquid nitrogen storage tank. An external liquid oxygen storage tank is adopted to supply liquid oxygen into the liquid oxygen storage tank, and a small-flow liquid oxygen pump is used for pumping oxygen from the liquid oxygen storage tank to pressurize; an external liquid nitrogen storage tank is adopted to supply liquid nitrogen into the liquid nitrogen storage tank, and a small-flow liquid nitrogen pump is used for pumping nitrogen from the liquid nitrogen storage tank to pressurize. The air separation device is not required to be started, so that small-flow oxygen and small-flow nitrogen can be provided, and the burner of the gasifier can be debugged and stopped for maintenance.
The backup system of the air separation unit is safer and more complete through a simple and economic mode, the requirements of small-flow oxygen supply for debugging a burner of a gasification furnace, small-flow nitrogen supply for daily maintenance during shutdown of the air separation unit and the like can be met, and the economic cost is saved.
In a preferred embodiment, the low flow liquid oxygen pump is electrically connected to the first transmission and the low flow liquid nitrogen pump is electrically connected to the second transmission. The speed change device can be a frequency converter, the rotating speed of the small-flow liquid oxygen pump or the small-flow liquid nitrogen pump can be adjusted through the speed change device according to user requirements, the pressure of oxygen or nitrogen can be controlled, the allowance size can be adjusted, and the adjusting speed is high.
In a preferred embodiment, a liquid oxygen sending valve is arranged between the liquid oxygen storage tank and the small-flow liquid oxygen pump; a liquid nitrogen sending valve is arranged between the liquid nitrogen storage tank and the small-flow liquid nitrogen pump. And during the normal operation of the IGCC unit, closing the liquid oxygen delivery valve and the liquid nitrogen delivery valve, and not operating the small-flow oxygen supply system and the small-flow nitrogen supply system. During the standby period of the IGCC unit, the liquid oxygen delivery valve is opened, the small-flow liquid oxygen pump is started to output small-flow oxygen, and the small-flow liquid oxygen is used for debugging a burner of a gasification furnace; and opening a liquid nitrogen delivery valve, starting a small-flow liquid nitrogen pump, and outputting small-flow nitrogen for the unit to be standby and maintained.
In the description of the present specification, the terms "connect", "mount", "fix", and the like are to be understood in a broad sense, for example, "connect" may be a fixed connection, a detachable connection, or an integral connection; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.
In the description of the present application, the description of the terms "one embodiment," "some embodiments," etc. means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (3)
1. A method for supplying oxygen and nitrogen with small flow for an air separation plant is characterized by comprising the following steps:
supplying oxygen at a small flow rate, wherein an external liquid oxygen storage tank is communicated with a liquid oxygen storage tank at the output end of an air separation device, a small-flow liquid oxygen pump is communicated with the liquid oxygen storage tank, a liquid oxygen water bath type vaporizer is arranged at the output end of the small-flow liquid oxygen pump, low-pressure steam is introduced into a water bath of the liquid oxygen water bath type vaporizer to control the temperature of oxygen, the oxygen enters the liquid oxygen water bath type vaporizer to be heated and vaporized after being pressurized by the small-flow liquid oxygen pump, and the vaporized oxygen enters a medium-pressure oxygen pipe network to be used for debugging a burner of a gasification furnace;
and supplying nitrogen at a small flow rate, wherein an external liquid nitrogen storage tank is communicated with a liquid nitrogen storage tank at the output end of the air separation device, a small-flow liquid nitrogen pump is communicated with the liquid nitrogen storage tank, a liquid nitrogen water bath type vaporizer is arranged at the output end of the small-flow liquid nitrogen pump, and nitrogen enters the liquid nitrogen water bath type vaporizer for vaporization after being pressurized by the small-flow liquid nitrogen pump and then enters a high-pressure nitrogen pipe network for equipment maintenance.
2. The method for air separation plant small flow oxygen feed and nitrogen of claim 1 wherein the small flow liquid oxygen pump is electrically connected to a first variable speed device and the small flow liquid nitrogen pump is electrically connected to a second variable speed device.
3. The method for supplying oxygen and nitrogen at a small flow rate of an air separation plant according to claim 2, characterized in that a liquid oxygen sending valve is arranged between the liquid oxygen storage tank and the liquid oxygen pump at a small flow rate; and a liquid nitrogen delivery valve is arranged between the liquid nitrogen storage tank and the small-flow liquid nitrogen pump.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110157832.4A CN112944804A (en) | 2021-02-04 | 2021-02-04 | Method for supplying oxygen and nitrogen with small flow for air separation device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110157832.4A CN112944804A (en) | 2021-02-04 | 2021-02-04 | Method for supplying oxygen and nitrogen with small flow for air separation device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112944804A true CN112944804A (en) | 2021-06-11 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110157832.4A Pending CN112944804A (en) | 2021-02-04 | 2021-02-04 | Method for supplying oxygen and nitrogen with small flow for air separation device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112944804A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113606868A (en) * | 2021-08-20 | 2021-11-05 | 中国联合重型燃气轮机技术有限公司 | IGCC, IGCC control method, and air separation system for IGCC |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103322411A (en) * | 2013-07-16 | 2013-09-25 | 兖矿集团有限公司 | Chemical system stoppage protective device |
| CN204594093U (en) * | 2015-03-19 | 2015-08-26 | 中化重庆涪陵化工有限公司 | The follow-up safeguards system of synthetic ammonia air separation unit |
| CN205316814U (en) * | 2016-01-08 | 2016-06-15 | 上海穗杉实业有限公司 | Fleet's oxygen suppliment, confession nitrogen support system |
| CN206814713U (en) * | 2017-06-20 | 2017-12-29 | 新疆心连心能源化工有限公司 | A kind of gasification furnace online fall stove oxygen ensuring equipment |
| US20200333070A1 (en) * | 2017-12-26 | 2020-10-22 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | System and method for supplying backup production in air separation device |
-
2021
- 2021-02-04 CN CN202110157832.4A patent/CN112944804A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103322411A (en) * | 2013-07-16 | 2013-09-25 | 兖矿集团有限公司 | Chemical system stoppage protective device |
| CN204594093U (en) * | 2015-03-19 | 2015-08-26 | 中化重庆涪陵化工有限公司 | The follow-up safeguards system of synthetic ammonia air separation unit |
| CN205316814U (en) * | 2016-01-08 | 2016-06-15 | 上海穗杉实业有限公司 | Fleet's oxygen suppliment, confession nitrogen support system |
| CN206814713U (en) * | 2017-06-20 | 2017-12-29 | 新疆心连心能源化工有限公司 | A kind of gasification furnace online fall stove oxygen ensuring equipment |
| US20200333070A1 (en) * | 2017-12-26 | 2020-10-22 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | System and method for supplying backup production in air separation device |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113606868A (en) * | 2021-08-20 | 2021-11-05 | 中国联合重型燃气轮机技术有限公司 | IGCC, IGCC control method, and air separation system for IGCC |
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Application publication date: 20210611 |