CN111197593A - Air separation unit air compressor surge-proof blow-down valve control method - Google Patents
Air separation unit air compressor surge-proof blow-down valve control method Download PDFInfo
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- CN111197593A CN111197593A CN201811374959.6A CN201811374959A CN111197593A CN 111197593 A CN111197593 A CN 111197593A CN 201811374959 A CN201811374959 A CN 201811374959A CN 111197593 A CN111197593 A CN 111197593A
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- valve
- air compressor
- emptying valve
- logic mode
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/02—Surge control
- F04D27/0207—Surge control by bleeding, bypassing or recycling fluids
- F04D27/0215—Arrangements therefor, e.g. bleed or by-pass valves
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/001—Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Control Of Positive-Displacement Air Blowers (AREA)
Abstract
The invention discloses an anti-surge vent valve control method for an air compressor of an air separation device, which comprises a vent valve control logic mode and a vent valve test logic mode associated with the vent valve control logic mode, wherein when the vent valve test logic mode is selected on an OIS operation station, a D0 digital quantity output function block and an A0 analog quantity output function block which outputs to a valve positioner for controlling the opening degree of a valve are both arranged in the vent valve test logic mode, when the vent valve is in the vent valve test logic mode, the D0 digital quantity output function block outputs to an electromagnetic valve for power on or power off, when the electromagnetic valve is in the power on state, the A0 analog quantity output function block can be changed by inputting numerical values to output corresponding output signals to the positioner, and the vent valve can move to reach the corresponding opening degree through the positioner. The invention avoids the negative effects caused by the forced halt treatment of the air compressor halfway in the normal operation process of starting the air compressor, namely meaningless energy consumption and the influence on the production rhythm and the productivity of a user.
Description
Technical Field
The invention relates to control of a vent valve of a centrifugal air compressor of an air separation device, in particular to a method for controlling the anti-surge vent valve of the air compressor of the air separation device.
Background
In the air separation type oxygen production industry, an air compressor is a main raw material (namely air) supply device and is responsible for sucking the atmosphere with mechanical particles, impurities and dust filtered by a front-end air filter, compressing and boosting the pressure to a certain pressure for the use of the next procedure.
According to the air separation process characteristics and the requirement of capacity, the air compressor is generally a centrifugal compressor, and the centrifugal compressor has the possibility of surging in the working process. Surge is a phenomenon peculiar to a centrifugal compressor, and when discharge flow rate decreases to a certain interval due to increase of outlet pressure, the compressor enters a surge region, and when surge occurs, airflow flows back and forth in the compressor, the flow rate fluctuates greatly, a unit vibrates violently, and the compressor is damaged extremely by long-time surge, so that anti-surge control is required.
According to the performance curve of the compressor under different working conditions, the compressor can work normally only by controlling the minimum flow corresponding to the outlet pressure of the compressor in a working area. The control object of the anti-surge of the air compressor is the emptying valve, and the emptying valve is automatically opened when the pressure at the outlet of the air compressor rises and the flow rate drops to be close to the surge area, so that the flow rate of gas flowing through the air compressor is increased, and the working condition of the compressor is pulled back to the normal working area. Simultaneously, the atmospheric valve still plays the effect of adjusting air compressor machine outlet pressure to match the demand of follow-up process.
In the process of starting the air separation device for several times, when the starting process of the air compressor is completed, after the sweeping and replacement of the rear pipeline and equipment are completed, when the increment adjustment is carried out on the air compressor, the surge phenomenon of the air compressor occurs, the production cannot be continued, and the air compressor can only be stopped to check. The field inspection finds that the phenomenon of surging occurs because the control signal from the DCS control system to the valve cannot be correctly executed because the air compressor blow-down valve is inflexible in action, jammed, not in place and the like. The reason was analyzed as follows:
the air compressor matched with the air separation device, and the control object of the anti-surge is an emptying valve PCV 1143. The valve is a regulator valve equipped with a solenoid valve and a valve positioner. The DCS for controlling the production process has 2 paths of output signals to control the action of the emptying valve. One path of digital quantity is output to a relay to control the solenoid valve to be powered on or powered off. One path of 4-20mA analog quantity is output to a valve positioner to control the opening of the valve. After the electromagnetic valve is electrified to open the output gas circuit of the valve positioner, the valve positioner controlled by 4-20mA analog quantity can output air pressure to enter the actuating mechanism cylinder of the emptying valve, and the valve is pushed to move to reach the required control opening degree of the DCS. When the electromagnetic valve is powered off, the air pressure of an actuating mechanism cylinder for pushing the emptying valve is released, and the emptying valve is always in a full-open position under the action of the spring of the actuating mechanism.
At present, if the air compressor is started to operate for a period of time, the air release valve is required to be involved to perform anti-surge regulation, and the air release valve is abnormal in action and can only be stopped forcibly. And (4) after the machine is stopped, carrying out rust loosening and lubricating treatment on the rotary jamming part of the valve, and starting the machine again after the machine is recovered to the state. Before the machine is forced to stop, the air compressor consumes a large amount of electric energy and does useless work. Moreover, production operators and equipment maintenance personnel are very passive, and the production rhythm and the yield of users are influenced because required gas cannot be supplied to the main production line in time.
As shown in figure 1, when any one of the conditions of high outlet pressure of the air compressor, the stop state of the air compressor, heavy fault of the air compressor and process interlocking is met, the DCS sends a cutting signal to the digital quantity output block PCV-1143-E1 for controlling the action of the electromagnetic valve through the OR gate logic, and the electromagnetic valve cuts off the valve positioner to output an air path, so that the emptying valve is forced to be fully opened.
When the outlet pressure of the air compressor is high, the air compressor is in a stop state, the air compressor has a heavy fault, and the process interlocking conditions are normal, the electromagnetic valve is switched on. The emptying valve acts according to an anti-surge control logic, namely, the output signals of the manual operator HIC-1143, the pressure regulator PICS-1143 and the flow regulator FRCAS-1101 are subjected to high selection, the result is correspondingly 4-20mA through the analog quantity output block PCV-1143-AO, and the valve positioner is driven by the 4-20mA to reach the specified opening degree.
Wherein, the set value SV of the pressure regulator PICS-1143 is manually set by an operator of an OIS operator interface station, and the measured value PV is from an on-site air compressor outlet pressure transmitter PT-1143.
The flow regulator FRCAS-1101 set value SV is calculated according to the outlet pressure PT-1143 of the air compressor and the characteristic curve function of the air compressor, namely the corresponding required minimum flow under the pressure PT-1143. The measured value PV is an on-site air compressor outlet flow transmitter FT-1101.
It can be seen from the original schematic diagram of the control logic of the air compressor, that in the operating state of the air compressor, the control of the air compressor is performed, an operator only sets the set value SV of the air compressor outlet pressure regulator PICS-1143 through an OIS operator interface station, and limits the closing function of the air compressor through the output value of the manual operator HIC-1143, and the control of other air compressors is automatically completed by the DCS control system. And when the air compressor is in a stop state, the air release valve cannot act in the whole process due to the power failure of the electromagnetic valve.
In the prior patent application, a valve control system and method thereof, as disclosed in application No. 201110402270.1, includes a step motor capable of controlling the rotation of a valve and a step motor controller for controlling the step motor, wherein the step motor controller includes a central processing unit, a step motor driving unit connected to the central processing unit via a serial bus, a PC control unit, a PLC control unit and an alarm information module; the PLC control unit can be connected with a PLC computer, and the valve is controlled by the PLC computer; the PC control unit can be connected with a personal computer, and the personal computer controls the valve. The valve control system of the invention can have two control modes, can control a plurality of valves and has high integration level. The invention relates to a control method for an electric valve which takes a stepping motor as an actuating mechanism and is formed by a control loop formed by hardware such as a personal computer, a PLC, the stepping motor and the like.
Also, as disclosed in application No. 201210114488.1, a surge control method of a centrifugal compressor apparatus establishes a method of calculating a theoretical surge power of a fan based on a reference surge power in a reference state and comprehensively considering the influence of a fan rotation speed, an inlet pressure and an inlet temperature on the fan surge power, compares actual power actually measured under any condition with the theoretical surge power calculated under the same condition by a surge protection device, and sends an instruction by the surge protection device when the actual power is close to the surge power, so as to realize surge protection of the fan. The surge protection method can implement all-weather all-condition intelligent surge protection, thereby preventing equipment from being damaged due to surge and avoiding the loss of air volume adjusting range caused by inaccurate surge prediction in the traditional technology. The centrifugal compressor device related to the patent is a fan, detects power as a parameter of surge, and adopts inlet pressure and temperature to assist in detecting whether surge occurs, and mainly relates to a method for judging whether surge occurs and control.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide an anti-surge blow-down valve control method for an air compressor of an air separation device, which avoids the negative influence caused by the forced halt treatment of the air compressor halfway in the normal running process of starting the air compressor, namely, the influence of meaningless energy consumption on the production rhythm and capacity of a user.
In order to achieve the purpose, the invention adopts the following technical scheme:
a method for controlling an emptying valve of an air compressor of an air separation device for preventing surge comprises the following steps: the emptying valve control logic mode further comprises the following steps: and testing a logic mode of the emptying valve associated with the control logic mode of the emptying valve, and selecting a switching mode through the OIS operating station, wherein the method comprises the following steps:
when an air discharge valve control logic mode is selected on the OIS operation station, the control logic of the air discharge valve is executed according to the original anti-surge automatic control logic and is used in the normal operation state of the air compressor;
when an emptying valve test logic mode is selected on an OIS operation station, a D0 digital quantity output function block for controlling an emptying valve electromagnetic valve and an A0 analog quantity output function block for outputting to a valve positioner to control the opening degree of the valve are all arranged in the emptying valve test logic mode, when the emptying valve is in the emptying valve test logic mode, the D0 digital quantity output function block outputs to the electromagnetic valve to be powered on or powered off, when the electromagnetic valve is in a powered on state, the A0 analog quantity output function block can be changed through inputting numerical values to output corresponding output signals to the positioner, the emptying valve is enabled to move to reach the corresponding opening degree through the positioner for testing and checking the movement condition of the emptying valve, so that whether the emptying valve is normal or not is determined, whether the air compressor can be started or not is determined, if the emptying valve is abnormal, the emptying valve needs to be processed first, and then the air compressor is started after the processing is finished;
and after the test is finished, the emptying valve test logic mode needs to be switched to the emptying valve control logic mode through the OIS operation station.
The D0 digital quantity output function block and the A0 analog quantity output function block are both related to an air compressor running state signal, and a blow-down valve control logic mode can be selected on the OIS operation station only when the air compressor is in a stop state.
And the OIS operation station is provided with an air compressor operation man-machine interface for inputting instructions.
In the technical scheme, the air release valve control method for preventing the surge of the air compressor of the air separation device, provided by the invention, has the following beneficial effects:
1) when the air compressor is stopped for a long time, the air release valve test logic mode is adopted, and the DCS operator station is used for opening and closing the air release valve, so that the jamming fault phenomenon of the air release valve is avoided and delayed;
2) before the air separation device is started and the air compressor is started, the emptying valve action performance is tested and checked by using the emptying valve test logic mode, problems can be timely treated, the phenomenon that the air separation device is forced to stop after being started is avoided, and a large amount of energy waste is saved;
3) the invention ensures the perfect function of the emptying valve in the anti-surge control of the air compressor and avoids the damage of surge to the air compressor.
Drawings
FIG. 1 is a diagram of existing flare valve control logic;
FIG. 2 is a logic diagram for the vent valve test of the present invention;
FIG. 3 is a correlation diagram of a flare valve control logic pattern with a flare valve test logic pattern in accordance with the present invention;
FIG. 4 is a schematic view of an air compressor operating human-machine interface according to the present invention;
FIG. 5 is a schematic diagram of the vent valve test logic mode callout and shutoff according to the present invention.
Detailed Description
The technical scheme of the invention is further explained by combining the drawings and the embodiment.
Referring to fig. 2 to 5, the method for controlling a purge valve of an air compressor of an air separation plant according to the present invention includes: the control logic mode of the emptying valve (namely the existing automatic control logic for preventing surge) also comprises the following steps: and the air release valve test logic mode is associated with the air release valve control logic mode, and the selection switching mode is carried out through an OIS (oil in air) operating station, wherein the OIS operating station is provided with an air compressor operation human-computer interface, and the method specifically comprises the following steps:
an entrance button (shown in fig. 4) of an air compressor operation man-machine interface for testing "PCV-1143-TEST" is added, the button is clicked to pop out a specific TEST picture, and 6 controls are arranged on the picture, wherein 5 are click buttons, and 1 is a numerical value input box.
The MANUL button and the AUTO button are control mode buttons of the emptying valve, switching is realized by clicking the corresponding buttons, and when the air compressor is in the AUTO mode, the control logic of the emptying valve is executed according to the original anti-surge automatic control logic and is used for the air compressor in a normal operation state;
when the air valve is in the air valve test logic mode, the D0 digital quantity output function block for controlling the solenoid valve of the air valve and the A0 analog quantity output function block for controlling the valve opening degree of the valve positioner are all placed in the air valve test logic mode, when the air valve is in the air valve test logic mode, the D0 digital quantity output function block (PCV-1143-E1) is enabled to output power to the solenoid valve through clicking an 'ON/OFF' button, namely, when clicking 'ON', the D0 output signal of the PCV-1143-E1 in the air valve control logic is set to be '1', the solenoid valve is enabled, and when clicking 'OFF', the D0 output signal of the PCV-1143-E1 in the air valve control logic is set to be '0', and the solenoid valve is de-powered.
When the electromagnetic valve is in a power-on state, the output signal of the A0 analog output function block can be changed to be output to the positioner by inputting the numerical value in the numerical value input box, the vent valve is enabled to move to reach the corresponding opening degree through the positioner, the movement condition of the vent valve is tested and checked, whether the movement of the vent valve is normal is confirmed, whether the air compressor can be started is determined, if the movement of the vent valve is abnormal, the vent valve needs to be processed firstly, and the air compressor is started after the processing is finished.
The emptying valve test logic mode is additionally arranged for testing the action condition of the emptying valve under the shutdown state of the air compressor, and under the running state of the air compressor, the emptying valve is never allowed to be in the emptying valve test logic mode for protecting the equipment safety of the air compressor. Therefore, the PCV-1143-TEST inlet button in the air compressor operation human-machine interface is associated with an air compressor operation state signal, and the button is displayed in the air compressor operation human-machine interface only in the stop state of the air compressor and is not displayed in the operation state. Namely, the emptying valve always executes the anti-surge automatic control logic under the running state, and the control of the emptying valve cannot be manually interfered.
In order to prevent the failure of the anti-surge control function of the air vent valve after the next start of the air compressor caused by the fact that the test of the air vent valve test logic mode is finished and the mode is not switched to the air vent valve control logic mode in time. In an air compressor operation man-machine interface, a current test mode of an emptying valve is associated with an image EXIT button 'EXIT', and when the emptying valve control mode is in an emptying valve test logic mode of 'MANUL', the 'EXIT' button is hidden and cannot be clicked to EXIT. And the picture can be clicked to exit only after clicking to switch to the emptying valve control logic mode of 'AUTO', so that the control safety of the whole air compressor is ensured.
As shown in figure 5, the protection of the self safety of the equipment of the air compressor is a primary target at any time, and the damage to the air compressor body is prevented by the runaway of the anti-surge automatic regulating function of the emptying valve due to the misoperation of an operator. Therefore, the invention also designs the calling-out of the test mode on the OIS station picture, and the closing function is logically associated after the test is finished. Namely, the valve test is not allowed to be called under the running state of the air compressor, and after the test is finished, the automatic surge prevention control state is switched to, and the test function can be closed and quit. The possibility of out-of-control of the anti-surge control function of the emptying valve is avoided.
In summary, the invention adds the function of testing and checking the operation state of the vent valve by modifying the control logic of the vent valve on the premise of not influencing the anti-surge automatic control function of the vent valve, so that the working state and the output value of the PCV-1143-E1 digital output DO functional module and the PCV-1143 analog output AO functional module can be controlled by the DCS operator interface station when the air compressor is in the shutdown state, that is, the automatic output of the DO and AO selection anti-surge control or the manual output of the operator at the OIS operator interface station can be changed, and corresponding operation control buttons and picture configurations are added on the picture of the OIS station to complete the execution of the control logic.
It should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that changes and modifications to the above described embodiments are within the scope of the claims of the present invention as long as they are within the spirit and scope of the present invention.
Claims (3)
1. A method for controlling an emptying valve of an air compressor of an air separation device for preventing surge comprises the following steps: the emptying valve control logic mode is characterized by further comprising the following steps: and testing a logic mode of the emptying valve associated with the control logic mode of the emptying valve, and selecting a switching mode through the OIS operating station, wherein the method comprises the following steps:
when an air discharge valve control logic mode is selected on the OIS operation station, the control logic of the air discharge valve is executed according to the original anti-surge automatic control logic and is used in the normal operation state of the air compressor;
when an emptying valve test logic mode is selected on an OIS operation station, a D0 digital quantity output function block for controlling an emptying valve electromagnetic valve and an A0 analog quantity output function block for outputting to a valve positioner to control the opening degree of the valve are all arranged in the emptying valve test logic mode, when the emptying valve is in the emptying valve test logic mode, the D0 digital quantity output function block outputs to the electromagnetic valve to be powered on or powered off, when the electromagnetic valve is in a powered on state, the A0 analog quantity output function block can be changed through inputting numerical values to output corresponding output signals to the positioner, the emptying valve is enabled to move to reach the corresponding opening degree through the positioner for testing and checking the movement condition of the emptying valve, so that whether the emptying valve is normal or not is determined, whether the air compressor can be started or not is determined, if the emptying valve is abnormal, the emptying valve needs to be processed first, and then the air compressor is started after the processing is finished;
and after the test is finished, the emptying valve test logic mode needs to be switched to the emptying valve control logic mode through the OIS operation station.
2. The air separation plant air compressor surge-proof blow-down valve control method as claimed in claim 1, characterized in that: the D0 digital quantity output function block and the A0 analog quantity output function block are both related to an air compressor running state signal, and a blow-down valve control logic mode can be selected on the OIS operation station only when the air compressor is in a stop state.
3. The air separation plant air compressor surge-proof blow-down valve control method as claimed in claim 1, characterized in that: and the OIS operation station is provided with an air compressor operation man-machine interface for inputting instructions.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811374959.6A CN111197593A (en) | 2018-11-19 | 2018-11-19 | Air separation unit air compressor surge-proof blow-down valve control method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811374959.6A CN111197593A (en) | 2018-11-19 | 2018-11-19 | Air separation unit air compressor surge-proof blow-down valve control method |
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| CN111197593A true CN111197593A (en) | 2020-05-26 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113819086A (en) * | 2021-11-09 | 2021-12-21 | 大连鼎力交通轨道设备有限公司 | Method for testing air volume change value of traction fan |
| CN116221191A (en) * | 2023-05-06 | 2023-06-06 | 西门子能源有限公司 | Fluid compression system and method of controlling a fluid compression system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11294380A (en) * | 1998-04-10 | 1999-10-26 | Mitsubishi Heavy Ind Ltd | Gas compression unit |
| CN102607826A (en) * | 2011-12-31 | 2012-07-25 | 杭州哲达科技股份有限公司 | Anti-surging valve performance testing table based on PLC (Programmable Logic Controller) and testing method |
| CN103852245A (en) * | 2012-12-04 | 2014-06-11 | 华东理工大学 | Test device and test method for testing heat-state mechanical performance of safety valve |
| CN105864086A (en) * | 2016-05-05 | 2016-08-17 | 沈阳鼓风机集团股份有限公司 | Fully automatic starting control system for high-speed centrifugal blower |
| CN105864087A (en) * | 2016-05-05 | 2016-08-17 | 沈阳鼓风机集团股份有限公司 | Fully automatic starting control method for high-speed centrifugal blower |
-
2018
- 2018-11-19 CN CN201811374959.6A patent/CN111197593A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11294380A (en) * | 1998-04-10 | 1999-10-26 | Mitsubishi Heavy Ind Ltd | Gas compression unit |
| CN102607826A (en) * | 2011-12-31 | 2012-07-25 | 杭州哲达科技股份有限公司 | Anti-surging valve performance testing table based on PLC (Programmable Logic Controller) and testing method |
| CN103852245A (en) * | 2012-12-04 | 2014-06-11 | 华东理工大学 | Test device and test method for testing heat-state mechanical performance of safety valve |
| CN105864086A (en) * | 2016-05-05 | 2016-08-17 | 沈阳鼓风机集团股份有限公司 | Fully automatic starting control system for high-speed centrifugal blower |
| CN105864087A (en) * | 2016-05-05 | 2016-08-17 | 沈阳鼓风机集团股份有限公司 | Fully automatic starting control method for high-speed centrifugal blower |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113819086A (en) * | 2021-11-09 | 2021-12-21 | 大连鼎力交通轨道设备有限公司 | Method for testing air volume change value of traction fan |
| CN116221191A (en) * | 2023-05-06 | 2023-06-06 | 西门子能源有限公司 | Fluid compression system and method of controlling a fluid compression system |
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Application publication date: 20200526 |