CN111023700A - Method for identifying and processing pseudo nitrogen plug of crude argon system to improve argon yield - Google Patents
Method for identifying and processing pseudo nitrogen plug of crude argon system to improve argon yield Download PDFInfo
- Publication number
- CN111023700A CN111023700A CN201911400888.7A CN201911400888A CN111023700A CN 111023700 A CN111023700 A CN 111023700A CN 201911400888 A CN201911400888 A CN 201911400888A CN 111023700 A CN111023700 A CN 111023700A
- Authority
- CN
- China
- Prior art keywords
- argon
- crude argon
- yield
- value
- crude
- 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.)
- Pending
Links
Images
Classifications
-
- 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
- F25J3/04642—Recovering noble gases from air
- F25J3/04648—Recovering noble gases from air argon
- F25J3/04654—Producing crude argon in a crude argon column
-
- 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
- F25J3/04642—Recovering noble gases from air
- F25J3/04648—Recovering noble gases from air argon
- F25J3/04654—Producing crude argon in a crude argon column
- F25J3/04666—Producing crude argon in a crude argon column as a parallel working rectification column of the low pressure column in a dual pressure main column system
- F25J3/04672—Producing crude argon in a crude argon column as a parallel working rectification column of the low pressure column in a dual pressure main column system having a top condenser
- F25J3/04678—Producing crude argon in a crude argon column as a parallel working rectification column of the low pressure column in a dual pressure main column system having a top condenser cooled by oxygen enriched liquid from high pressure column bottoms
-
- 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
- F25J3/04642—Recovering noble gases from air
- F25J3/04648—Recovering noble gases from air argon
- F25J3/04654—Producing crude argon in a crude argon column
- F25J3/04666—Producing crude argon in a crude argon column as a parallel working rectification column of the low pressure column in a dual pressure main column system
- F25J3/04672—Producing crude argon in a crude argon column as a parallel working rectification column of the low pressure column in a dual pressure main column system having a top condenser
- F25J3/04703—Producing crude argon in a crude argon column as a parallel working rectification column of the low pressure column in a dual pressure main column system having a top condenser being arranged in more than one vessel
-
- 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
- F25J3/04763—Start-up or control of the process; Details of the apparatus used
- F25J3/04769—Operation, control and regulation of the process; Instrumentation within the process
- F25J3/04793—Rectification, e.g. columns; Reboiler-condenser
- F25J3/048—Argon recovery
-
- 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
- F25J2235/00—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams
- F25J2235/58—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams the fluid being argon or crude argon
-
- 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
- F25J2245/00—Processes or apparatus involving steps for recycling of process streams
- F25J2245/58—Processes or apparatus involving steps for recycling of process streams the recycled stream being argon or crude argon
Landscapes
- Engineering & Computer Science (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 identifying and processing a pseudo nitrogen plug of a crude argon system to improve argon yield. The method comprises the following steps: 1) and calculating the corresponding crude argon yield of the argon fraction fluctuation interval according to a theoretical calculation method. 2) When the argon fraction is reduced for some reason (or not adjusted in time), the crude argon yield should be reduced in time, and the value of the argon fraction is adjusted to be increased to the interval of 8-10%. 3) When the working condition of the main tower is normal, the resistance, the flow and the temperature of the crude argon system are not obviously changed, only the purity of the crude argon is reduced, the yield of the crude argon is reduced, and the argon fraction is improved. The decrease in crude argon purity is not due to the high nitrogen content "nitrogen races", so this incorrect judgment is called "false nitrogen races". The reason for the sudden drop in crude argon purity under normal operating conditions is that the crude argon yield is greater than the corresponding feed gas amount.
Description
Technical Field
The invention relates to a method for identifying and processing a pseudo nitrogen plug of a crude argon system to improve argon yield.
Background
The argon production from an air separation unit is limited by various factors and the argon production is severely affected by the "nitrogen plug" in the crude argon column. The method is characterized in that the abnormal phenomenon that the purity of crude argon is suddenly reduced frequently occurs in the operation period of a unit, all parameters of an argon system are in a controllable range before abnormality, the value of argon fraction is 6.5-8.5%, when the value of argon fraction is increased from low to high, the purity of the crude argon is reduced from normal 99.6% Ar frequently, the reduction limit value is different every time, operators consider that a crude argon tower contains high nitrogen and consider that the nitrogen is a nitrogen match phenomenon, the yield of the argon is amplified so as to discharge nitrogen components of the nitrogen match in the crude argon tower, the current situation is called a 'pseudo nitrogen plug', and if the 'pseudo nitrogen plug' is not effectively processed, the working condition of the argon system and the working condition of a main tower are deteriorated, so that the yield of the argon is reduced. In the prior art, the adjustment is to judge whether a nitrogen plug exists according to the change of the argon fraction value, the liquid level and the flow of the crude argon condenser, and the method has poor effectiveness, is not timely and has no data theory support. And secondly, obtaining the nitrogen content by using the oxygen content value of the argon fraction, and adjusting the nitrogen content when the nitrogen content is increased when the argon fraction value is increased from low to high, so that the crude argon purity is not reduced.
Disclosure of Invention
The invention aims to provide a method for identifying and processing a pseudo nitrogen plug of a crude argon system to improve argon yield, which can solve the problems of sudden reduction of crude argon purity of an air separation system, nitrogen plugs of a crude argon tower and the pseudo nitrogen plug, solve the problem that the crude argon system is low in argon yield due to frequent nitrogen plugs, keep working condition steady operation and achieve the purpose of improving argon yield.
The object of the invention is achieved by a method for identifying a pseudo nitrogen plug in a crude argon system for improving argon production,
1) calculating the corresponding crude argon yield of the argon fraction fluctuation interval according to a theoretical calculation method;
2) when the argon fraction is lowered for some reason or not adjusted in time, the crude argon yield should be reduced in time, and the value of the argon fraction is adjusted to be increased to the interval of 8-10 percent;
3) when the working condition of the main tower is normal, the resistance, the flow and the temperature of the crude argon system are not obviously changed, only the purity of the crude argon is reduced, the yield of the crude argon is reduced, and the argon fraction is improved;
4) calculating the operating value of FIC702 according to the value of AIA701 and the value of FIA701 in a process diagram of an air separation crude argon system, thereby ensuring that the value of AIA705 is more than 95 percent, solving the problem of the purity reduction of the AIA705 crude argon and ensuring that the yield of FIC702 crude argon is not influenced by the purity reduction;
5) the opening degree of a V701 valve in a process diagram of the air separation crude argon system is matched with the liquid level of liquid and air of a crude argon condenser;
6) in the process diagram of the air separation crude argon system, a V701 valve is closed down to reduce nitrogen components in reflux liquid in a crude argon liquid-air condenser and then the nitrogen components are extracted by argon fraction, then the value of the argon fraction is increased to reach the highest value, if the value is not at the highest value, nitrogen blockage occurs, the V701 valve is continuously closed down until the argon fraction value does not occur when the highest value operates, the opening degree of the V701 valve is proper, and at the moment, the argon yield is calculated according to the argon fraction value.
6.5-8.5% of argon fraction; crude argon fraction 48000m 3/h;
the purity of the crude argon is 99.65%; crude argon yield 1250m3/h
A. When the argon fraction is at 6.5%, the theoretical yield of crude argon is: 48000 × 6.5%/3.3=945m3/h
B. When the argon fraction is at 8.5%, the theoretical yield of crude argon is: 48000 × 8.5%/3.3=1236m3/h
C. From theoretical calculations, it can be seen that the crude argon yield of the argon fraction at 6.5% is 945m3/h, the crude argon yield at 8.5% is 1236m3/h, but the crude argon yield is 1250m3/h in actual operation, the material imbalance of the argon component, the process argon of 945m3/h can be produced by the argon fraction at 6.5%, but the crude argon yield is far greater than the theoretical yield in actual operation, so the crude argon purity is reduced, and the degree and the time of the reduction depend on the recovery time of the value of the argon fraction.
From the above calculations and analyses, it was found that the reduction in crude argon purity was not due to the high nitrogen content "nitrogen races", so this incorrect judgment was called "false nitrogen races". The reason for the sudden drop in crude argon purity under normal operating conditions is that the crude argon yield is greater than the corresponding feed gas amount.
The treatment method comprises the following steps:
in view of the above analysis, the following approach can be taken to deal with the crude argon purity reduction:
1) and calculating the corresponding crude argon yield of the argon fraction fluctuation interval according to a theoretical calculation method.
2) When the argon fraction is reduced for some reason (or not adjusted in time), the crude argon yield should be reduced in time, and the value of the argon fraction is adjusted to be increased to the interval of 8-10%.
3) When the working condition of the main tower is normal, the resistance, the flow and the temperature of the crude argon system are not obviously changed, only the purity of the crude argon is reduced, the yield of the crude argon is reduced, and the argon fraction is improved. The crude argon yield is amplified instead, and the control value of the argon fraction is intentionally reduced, so that the purity of the crude argon is accelerated to be reduced, and finally the nitrogen match is caused.
The problem that the yield of argon is low due to frequent nitrogen blockage of a crude argon system is solved;
1) as shown in the process diagram of the air separation crude argon system, the operating value of the 3-point FIC702 is calculated according to the value of the 1-point AIA701 and the value of the 2-point FIA701 in the diagram, so that the value of the 4-point AIA705 is ensured to be more than 95 percent. The method solves the problem of the purity reduction of the crude argon of the AIA705, and ensures that the yield of the crude argon of the FIC702 is not influenced by the purity reduction.
2) The opening degree of a V701 valve in a point 5 in a process diagram of an air separation crude argon system is not easy to be overlarge, and the opening degree is matched with the liquid level of liquid air of a crude argon condenser, so that the nitrogen content in crude argon is controllable, and the purpose of increasing yield is achieved.
3) The V701 valve is turned down in the process diagram of the air separation crude argon system, so that nitrogen components in reflux liquid in the crude argon liquid-air condenser can be reduced and extracted by argon fractions, then the argon fraction value is increased to the highest value, if the nitrogen plug does not occur at the highest value, the V701 valve is turned down continuously until the nitrogen plug does not occur when the argon fraction value operates at the highest value, the opening degree of the V701 valve is optimal, the argon yield can be calculated according to the argon fraction value at the moment, the argon fraction and the argon yield are kept to the maximum, and if the working condition is not abnormal, the design value can be exceeded, so that the purpose of increasing the argon yield is achieved.
After the technology is implemented, the crude argon system has no problem of sudden reduction of crude argon purity, the argon fraction can be stabilized at a higher level, and the argon yield is 1250m3The/h is stabilized at 1400m3The crude argon yield is improved by 10 percent, 4.6m3/d of liquid argon can be produced more every day, and the economic income is increased by 9200 yuan/day. The psychological condition that operators are afraid of the nitrogen match is eliminated, the working condition forms virtuous circle, the operating intensity of the operators is reduced, and the occurrence of operating accidents is avoided.
Drawings
The present invention will be described in further detail below with reference to the accompanying drawings.
FIG. 1 is a process diagram of the air separation crude argon system in the invention.
Detailed Description
A method for identifying and processing a pseudo nitrogen plug of a crude argon system to improve argon yield,
1) calculating the corresponding crude argon yield of the argon fraction fluctuation interval according to a theoretical calculation method;
2) when the argon fraction is lowered for some reason or not adjusted in time, the crude argon yield should be reduced in time, and the value of the argon fraction is adjusted to be increased to the interval of 8-10 percent;
3) when the working condition of the main tower is normal, the resistance, the flow and the temperature of the crude argon system are not obviously changed, only the purity of the crude argon is reduced, the yield of the crude argon is reduced, and the argon fraction is improved;
4) calculating the operating value of FIC702 at the 3 points according to the numerical value of AIA701 at the 1 point and the numerical value of FIA701 at the 2 points in FIG. 1, thereby ensuring that the numerical value of AIA705 at the 4 points is more than 95 percent, solving the problem of the reduction of the purity of the crude argon of AIA705 and ensuring that the yield of the crude argon of FIC702 is not influenced by the reduction of the purity;
5) the opening degree of a V701 valve at the 5 point in the figure 1 is matched with the liquid-air level of the crude argon condenser;
6) in FIG. 1, a 5-point V701 valve is closed to reduce nitrogen components in reflux liquid in a crude argon liquid-air condenser, the nitrogen components are extracted by argon fraction, then the value of the argon fraction is increased to the maximum value, if the value is not at the maximum value, a nitrogen plug appears, the V701 valve is continuously closed until the value of the argon fraction does not appear when the value is at the maximum value, the opening degree of the V701 valve is proper, and the argon yield is calculated according to the value of the argon fraction.
Claims (1)
1. A method for identifying and processing a pseudo nitrogen plug of a crude argon system to improve argon yield is characterized by comprising the following steps:
1) calculating the corresponding crude argon yield of the argon fraction fluctuation interval according to a theoretical calculation method;
2) when the argon fraction is lowered for some reason or not adjusted in time, the crude argon yield should be reduced in time, and the value of the argon fraction is adjusted to be increased to the interval of 8-10 percent;
3) when the working condition of the main tower is normal, the resistance, the flow and the temperature of the crude argon system are not obviously changed, only the purity of the crude argon is reduced, the yield of the crude argon is reduced, and the argon fraction is improved;
4) calculating the operating value of FIC702 according to the value of AIA701 and the value of FIA701 in a process diagram of an air separation crude argon system, thereby ensuring that the value of AIA705 is more than 95 percent, solving the problem of the purity reduction of the AIA705 crude argon and ensuring that the yield of FIC702 crude argon is not influenced by the purity reduction;
5) the opening degree of a V701 valve in a process diagram of the air separation crude argon system is matched with the liquid level of liquid and air of a crude argon condenser;
6) in the process diagram of the air separation crude argon system, a V701 valve is closed down to reduce nitrogen components in reflux liquid in a crude argon liquid-air condenser and then the nitrogen components are extracted by argon fraction, then the value of the argon fraction is increased to reach the highest value, if the value is not at the highest value, nitrogen blockage occurs, the V701 valve is continuously closed down until the argon fraction value does not occur when the highest value operates, the opening degree of the V701 valve is proper, and at the moment, the argon yield is calculated according to the argon fraction value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911400888.7A CN111023700A (en) | 2019-12-31 | 2019-12-31 | Method for identifying and processing pseudo nitrogen plug of crude argon system to improve argon yield |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911400888.7A CN111023700A (en) | 2019-12-31 | 2019-12-31 | Method for identifying and processing pseudo nitrogen plug of crude argon system to improve argon yield |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111023700A true CN111023700A (en) | 2020-04-17 |
Family
ID=70196277
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911400888.7A Pending CN111023700A (en) | 2019-12-31 | 2019-12-31 | Method for identifying and processing pseudo nitrogen plug of crude argon system to improve argon yield |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111023700A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20040045315A1 (en) * | 2002-07-01 | 2004-03-11 | Tomoyoshi Kamoshita | Method and device for producing oxygen |
| JP2004345881A (en) * | 2003-05-21 | 2004-12-09 | Nippon Sanso Corp | Argon purification apparatus and its operation method |
| CN101634837A (en) * | 2009-08-17 | 2010-01-27 | 浙江大学 | Method for preventing and controlling nitrogen blockage of argon preparation system of space division device |
| CN106225422A (en) * | 2016-07-27 | 2016-12-14 | 杭州杭氧股份有限公司 | A kind of Automatic load change optimal control method for interior compression strap argon air separation plant |
| CN109973412A (en) * | 2017-12-27 | 2019-07-05 | 沈阳自动化研究所(昆山)智能装备研究院 | One kind being used for external compression air separation unit oxygen compressor anti-asthma method of slight |
-
2019
- 2019-12-31 CN CN201911400888.7A patent/CN111023700A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20040045315A1 (en) * | 2002-07-01 | 2004-03-11 | Tomoyoshi Kamoshita | Method and device for producing oxygen |
| JP2004345881A (en) * | 2003-05-21 | 2004-12-09 | Nippon Sanso Corp | Argon purification apparatus and its operation method |
| CN101634837A (en) * | 2009-08-17 | 2010-01-27 | 浙江大学 | Method for preventing and controlling nitrogen blockage of argon preparation system of space division device |
| CN106225422A (en) * | 2016-07-27 | 2016-12-14 | 杭州杭氧股份有限公司 | A kind of Automatic load change optimal control method for interior compression strap argon air separation plant |
| CN109973412A (en) * | 2017-12-27 | 2019-07-05 | 沈阳自动化研究所(昆山)智能装备研究院 | One kind being used for external compression air separation unit oxygen compressor anti-asthma method of slight |
Non-Patent Citations (1)
| Title |
|---|
| 李化治: "《制氧技术》", 31 August 2009, 冶金工业出版社 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE112013001671B4 (en) | Method and apparatus for safety operation of a steam extraction turbine, which is used for a power plant | |
| CN105219899B (en) | A kind of method for early warning judging Blast Furnace Abnormal Conditions Judgement according to differential static pressure | |
| CN111023700A (en) | Method for identifying and processing pseudo nitrogen plug of crude argon system to improve argon yield | |
| CN101658913B (en) | Variable water ratio control method of secondary cooling of billet caster | |
| CN107096795A (en) | A kind of manufacture method for reducing edge defects of hot rolled strip steel | |
| CN110307212B (en) | Oil leakage monitoring method for hydraulic servo system | |
| CN109609832A (en) | A kind of smelting process of the vacuum consumable remelting production containing manganese steel | |
| CN106468879B (en) | A kind of liquid level-flow nonlinear area control method | |
| CN110307213B (en) | Oil leakage monitoring method for hydraulic conventional system | |
| CN113094896B (en) | Power plant heat supply unit optimization control method | |
| CN102517428B (en) | Method for producing low compression ratio crack detection thick plate | |
| CN109491416B (en) | Grouting stage boosting control method | |
| CN106988803A (en) | A kind of low pressure (LP) cylinder linear leaf cooling system and method based on extraction opening | |
| CN106312682A (en) | Adjustable high-pressure cooling device for high-temperature alloy turning | |
| CN106642072B (en) | Fired power generating unit desuperheating water tune valve discharge characteristic linearity correction and control method | |
| CN106929616A (en) | Blast furnace TRT system top pressure control methods | |
| CN108279101A (en) | A kind of liquid level variation tendency oil leak method for early warning | |
| CN106924986A (en) | Rectifying column top pressure stabilising arrangement | |
| CN109764638B (en) | Load-variable method for argon system of large oxygen generator set | |
| CN208364835U (en) | A kind of pair of stamp multilevel decompression ball valve core | |
| CN104950847B (en) | The computational methods of the self-optimizing controlled variable of forced-circulation evaporation control process in alkali liquor concentration production technology | |
| CN107723482A (en) | The method for controlling vanadium slag calcification baking clinker sulfuric acid leaching technological parameter | |
| CN203018866U (en) | Forming extrusion screw tap with multi-edge surface | |
| CN112914147A (en) | Method for stabilizing stem rejection rate of cut tobacco on-site air separation machine | |
| CN110090867A (en) | A method of piling of steel between edger roll and plain-barreled roll when plain-barreled roll being prevented to sting steel |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20200417 |
|
| WD01 | Invention patent application deemed withdrawn after publication |