A foam elimination control system and control method thereof

Abstract

The present invention discloses a foam elimination control system and a control method thereof, and relates to the technical field of foam elimination control. The technical solution of the present invention includes a radar level gauge, a differential pressure level gauge, a control terminal and a defoaming device. The radar level gauge measures the height of the alkali solution foam in the circulation tank to obtain a first height, and the differential pressure level gauge measures the level of the cleaning alkali solution in the circulation tank to obtain a second height; the amount of alkali solution foam generated is accurately obtained according to the difference between the first height and the second height; when the amount of generation is greater than a preset value, it indicates that there is a risk of the alkali solution foam overflowing the circulation tank, and a defoaming signal is output to the defoaming device to control the defoaming device to deliver a defoaming agent to the circulation tank, so that the alkali solution foam is eliminated in time. The technical solution of the embodiment of the present invention can pump the defoaming agent based on the accurate amount of alkali solution foam generated, thereby effectively preventing the cleaning alkali solution from overflowing from the top of the circulation tank.

Description

Technical Field

[0001] The present invention relates to the technical field of foam elimination control, and in particular to a foam elimination control system and a control method thereof. Background Art

[0002] The main function of the cold rolling decarburization annealing unit is to anneal and coat oriented silicon steel. The cleaning section is the strip cleaning process section in front of the annealing production line. It uses an efficient water-saving degreasing device and combines physical and chemical methods to clean the strip surface, remove oil and other impurities, and ensure the strip surface is clean. The cleaning effect directly affects the surface quality of silicon steel and the formation of oxide film, and is a very important link in the silicon steel production process.

[0003] A large amount of foam will be generated in the circulation process of washing strip steel with cleaning alkali solution (or flushing liquid). The foam will gradually accumulate in the circulation tank and eventually overflow from the top of the tank with a large amount of cleaning alkali solution, resulting in a huge waste of cleaning alkali solution. Summary of the invention

[0004] In order to solve the technical problem of how to prevent the cleaning alkali solution from overflowing from the top of the circulation tank, the present invention provides a foam elimination control system and a control method thereof, which can pump defoaming agent based on the accurate amount of alkali solution foam generated, thereby effectively preventing the cleaning alkali solution from overflowing from the top of the circulation tank.

[0005] The embodiment of the present invention provides the following solution:

[0006] In a first aspect, an embodiment of the present invention provides a foam elimination control system, the system comprising:

[0007] A radar level gauge is arranged on the top of a circulation tank containing cleaning alkali solution, and is used to measure the height of alkali solution foam in the circulation tank and output a first height;

[0008] The differential pressure level gauge is arranged inside the circulation tank, and is used to measure the level of the cleaning alkali solution in the circulation tank and output a second height;

[0009] A control terminal is connected to the radar level gauge and the differential pressure level gauge, and the control terminal is used to obtain the first height and the second height; determine the amount of alkali liquid foam generated according to the difference between the first height and the second height, and output a defoaming signal when the amount of foam generated is greater than a preset value;

[0010] The defoaming device is connected to the control terminal. When receiving the defoaming signal, the defoaming device is used to deliver the defoaming agent to the circulation tank so that the alkali solution foam is eliminated in time.

[0011] In an optional embodiment, the defoaming device comprises:

[0012] The atomizing assembly has an inlet connected to a storage tank containing a defoaming agent, and an outlet connected to a circulation tank. The atomizing assembly is used to atomize the defoaming agent output from the storage tank.

[0013] In an optional embodiment, the atomization assembly includes:

[0014] Atomizing nozzle;

[0015] The first pipe has one end connected to the storage tank and the other end equipped with an atomizing nozzle;

[0016] A first valve is installed on the first pipeline, and the first valve is used to control the flow state of the defoaming agent in the first pipeline;

[0017] A second pipeline, one end of which is connected to the compressed air network, and the other end of which is connected to the atomizing nozzle;

[0018] The second valve is installed on the second pipeline, and the second valve is used to control the flow state of compressed air in the second pipeline.

[0019] In an optional embodiment, the system further includes:

[0020] The tank level gauge is connected to the control terminal. The tank level gauge is used to measure the liquid level of the defoaming agent in the tank and output the third height to the processing terminal.

[0021] In an optional embodiment, the system further includes:

[0022] The nozzle is arranged on the side of the radar level gauge;

[0023] A third pipeline, one end of which is connected to the compressed air network and the other end of which is connected to the nozzle;

[0024] The solenoid valve is installed on the third pipeline, and is used to open when the surface of the radar level meter needs to be defogged to deliver compressed air to the nozzle.

[0025] In a second aspect, an embodiment of the present invention further provides a control method for a foam elimination control system, the system comprising a radar level gauge, a differential pressure level gauge, a control terminal and a defoaming device, the radar level gauge is arranged on the top of a circulation tank containing cleaning alkali solution, the differential pressure level gauge is arranged inside the circulation tank, the radar level gauge, the differential pressure level gauge and the defoaming device are all connected to the control terminal; the method comprises:

[0026] Obtaining a first height at which a radar level meter measures the height of alkali solution foam in a circulation tank, and a second height at which a differential pressure level meter measures the level of cleaning alkali solution in the circulation tank;

[0027] Determining the amount of alkali solution foam generated according to the difference between the first height and the second height;

[0028] When the generated amount is greater than a preset value, a defoaming signal is output to the defoaming device to control the defoaming device to deliver the defoaming agent to the circulation tank so that the alkali solution foam is eliminated in time.

[0029] In an optional embodiment, after outputting the defoaming signal to the defoaming device, the method further includes:

[0030] In a first time period, the defoaming device is controlled to quantitatively deliver the defoaming agent to the circulation tank according to a preset addition amount, and a first average consumption of the defoaming agent is obtained;

[0031] In the second period, the defoaming device is controlled to deliver a corresponding dose of defoaming agent to the circulation tank according to the generated amount, and a second average consumption of the defoaming agent is obtained;

[0032] The target delivery amount of the defoaming agent is determined according to the first average consumption and the second average consumption, wherein the target delivery amount is the minimum dosage of the defoaming agent to ensure that the alkali solution foam does not overflow the circulation tank.

[0033] In an optional embodiment, the method further includes:

[0034] Determine whether the cleaning alkali solution in the circulation tank is heated to a temperature exceeding a threshold value;

[0035] If so, a purge signal is output to control the solenoid valve to open, so that the nozzle connected to the solenoid valve purges the radar level gauge with compressed air for demisting.

[0036] In an optional embodiment, after outputting the defoaming signal to the defoaming device, the method further includes:

[0037] Opening a first valve on a first pipeline to a first opening, wherein the first pipeline is a pipeline on the defoaming device connecting an atomizing nozzle and a storage tank containing a defoaming agent;

[0038] The second valve on the second pipeline is opened to a second opening degree so that the defoaming agent delivered to the circulation tank is atomized to a target state, wherein the second pipeline is a pipeline connecting the compressed air and the atomizing nozzle.

[0039] In an optional embodiment, the method further includes:

[0040] Obtaining a third height for measuring the liquid level of the defoaming agent in the storage tank;

[0041] When the third height is lower than the height threshold, a liquid level alarm signal of the defoaming agent is output.

[0042] Compared with the prior art, the foam elimination control system and control method of the present invention have the following advantages:

[0043] The technical solution of the present invention includes a radar level gauge, a differential pressure level gauge, a control terminal and a defoaming device. The radar level gauge measures the height of the alkali solution foam in the circulation tank to obtain a first height, and the differential pressure level gauge measures the level of the cleaning alkali solution in the circulation tank to obtain a second height; the amount of alkali solution foam generated is accurately obtained according to the difference between the first height and the second height; when the amount generated is greater than a preset value, it indicates that there is a risk of the alkali solution foam overflowing the circulation tank, and a defoaming signal is output to the defoaming device to control the defoaming device to deliver the defoaming agent to the circulation tank, so that the alkali solution foam is eliminated in time. The technical solution of the embodiment of the present invention can pump the defoaming agent based on the accurate amount of alkali solution foam generated, thereby effectively preventing the cleaning alkali solution from overflowing from the top of the circulation tank. At the same time, precise control of the defoaming agent pumping is achieved, saving the amount of defoaming agent used. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A schematic structural diagram of a foam elimination control system provided in an embodiment of the present invention.

[0046] Figure 2 A composition layout diagram of a cleaning section device provided in an embodiment of the present invention;

[0047] Figure 3 A schematic diagram of the structure of an alkali spray and alkali brush device for a cleaning section provided in an embodiment of the present invention;

[0048] Figure 4 A schematic diagram of the height detection principle of alkali solution foam provided in an embodiment of the present invention;

[0049] Figure 5 A first structural schematic diagram of a defoaming device provided in an embodiment of the present invention;

[0050] Figure 6 A second structural schematic diagram of a defoaming device provided in an embodiment of the present invention;

[0051] Figure 7 A schematic diagram of the electrical structure of a foam elimination control system provided by an embodiment of the present invention;

[0052] Figure 8 A flow chart of a control method of a foam elimination control system provided by an embodiment of the present invention;

[0053] Fig. 9A control model distribution diagram of the foam elimination control system provided in an embodiment of the present invention.

[0054] Explanation of the accompanying drawings: 1- radar level gauge, 2- differential pressure level gauge, 3- control terminal, 4- defoaming device, 5- alkali spray tank, 6- alkali brush tank, 7- electrolytic cell, 8- water brush tank, 9- water washing tank, 10- drying equipment, 11- circulation tank, 12- brush roller, 13- spray beam, 14- squeeze roller, 15- strip steel, 16- alkali solution foam, 17- cleaning alkali solution, 18- storage tank, 19- atomizing nozzle, 20- first pipeline, 21- first valve, 22- second pipeline, 23- second valve, 24- compressed air pipeline network, 25- storage tank level gauge, 26- remote site, 27- PLC, 28- host computer. DETAILED DESCRIPTION

[0055] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the embodiments of the present invention.

[0056] In the entire cleaning section of the strip cleaning process, the alkaline brushing section and the electrolytic cleaning section are the most important parts of the cleaning section equipment, which directly affect the cleaning effect of the strip. Since these two sections use alkali solution as the main cleaning medium, a large amount of alkali solution foam and alkali vapor are inevitably generated during production. The supply and reflux of cleaning alkali solution are concentrated in the circulation tank for alkali brushing, so the foam generated is also mainly concentrated in the circulation tank. The method for dealing with alkali solution foam is to purchase a defoaming agent adding monomer equipment, install it in the cleaning section area, and lay a pipeline from the outlet of the pump group of this equipment to the circulation tank of the cleaning section. The pump group is used to extract the defoaming agent from the storage tank (or ton barrel), and the defoaming agent is transported to the circulation tank through the pipeline to add the defoaming agent to eliminate the foam. The effect after implementation is not ideal, which is mainly manifested in the following aspects:

[0057] (1)Since the silicon steel production line operates 24 hours a day, alkali foam is constantly generated in the cleaning section. In order to control this situation, a large amount of defoaming agent can only be added continuously, resulting in a significant increase in the cost per ton of steel.

[0058] (2) Alkali solution foam often overflows, resulting in a large amount of waste of cleaning alkali solution and increased costs.

[0059] (3) Pollute the surrounding environment and harm the health of workers.

[0060] (4) During the transportation, storage and addition of defoamers, not only the environment is polluted, but also special personnel are required to manage, which increases the labor input and the labor intensity. According to rough statistics, due to the consumption of defoamers, the waste of alkali solution, the replacement of spare parts caused by equipment corrosion and the input of personnel, nearly 500,000 yuan of funds are required each year, not including the cost of environmental pollution control. Therefore, it is urgent to solve the problem of defoaming alkali solution in the cleaning section. The following embodiments of the present invention will specifically explain how to solve the above problems.

[0061] See also Figure 1 , Figure 1 This is a structural schematic diagram of a foam elimination control system provided in an embodiment of the present invention. The control system includes a radar level gauge 1, a differential pressure level gauge 2, a control terminal 3 and a defoaming device 4.

[0062] The foam elimination control system can be installed in the cleaning section equipment to implement defoaming control. Figure 2 , Figure 2 This is the layout diagram of the cleaning section equipment. The cleaning section equipment mainly consists of an alkali spray tank 5, an alkali brush tank 6, an electrolytic tank 7, a water brush tank 8, a water washing tank 9 and a drying equipment 10. Please refer to Figure 3 The alkali brushing section includes an alkali spraying tank 5 and an alkali brushing tank 6. The alkali spraying tank 5 and the alkali brushing tank 6 are both connected to a circulation tank 11. The alkali spraying tank 5 and the alkali brushing tank 6 are also provided with a brush roller 12, a spray beam 13 and a squeeze roller 14. The strip steel 15 is cleaned by the brush roller 12 in the alkali spraying tank 5 and the alkali brushing tank 6, and at the same time, the cleaning alkali solution is sprayed by the spray beam 13.

[0063] The original equipment can only solve the problem of whether the defoaming agent can be added. In order to eliminate the foam, the defoaming agent is transported to the circulation tank 11 by a pump group. After the defoaming agent is added to the circulation tank 11, it reacts with the alkali solution foam to eliminate the foam, which can temporarily alleviate the excessive overflow of the alkali solution foam in the circulation tank 11. Because the amount of alkali solution foam generated in the circulation tank 11 cannot be detected, it is impossible to accurately control the required amount of defoaming agent to be added, resulting in excessive alkali solution foam in the circulation tank 11 carrying alkali solution and overflowing from the tank body, or excessive defoaming agent is added and mixed into the circulation system of the cleaning alkali solution; at the same time, the defoaming agent is directly introduced into the circulation tank through a pipeline, and the contact area with the alkali solution foam after flowing in is small, and the defoaming efficiency is low; this method of defoaming causes great cost waste.

[0064] The purpose of the present invention is to solve the problem of alkali liquid foam in the circulation tank of the alkali scrubbing section carrying alkali liquid overflow, adopt a stable and accurate method of detecting alkali liquid foam, and optimize the method of adding defoaming agent. After the system is modified, it can effectively eliminate the alkali liquid foam generated during the circulation process of the cleaning alkali liquid, and save the amount of defoaming agent, so as to suppress the overflow of the cleaning alkali liquid and alkali liquid foam with the minimum consumption of defoaming agent. The implementation scheme of the proposed foam elimination control system will be specifically described below.

[0065] See also Figure 4 , schematic diagram of height detection of alkali solution foam. The radar level meter 1 is arranged on the top of the circulation tank 11 containing the cleaning alkali solution, and its measuring range can be configured to be 0-5m. The radar level meter is used to measure the height of the alkali solution foam in the circulation tank and output a first height. The radar level meter 1 is a high-precision instrument for liquid level measurement using ultrasonic waves emitted by a radar. It determines the height of the liquid level by emitting ultrasonic waves and receiving the reflected signals. Due to the strong reflectivity of the foam surface, the ultrasonic wave is diffusely reflected on the foam surface, and the feedback signal received by the radar level meter is the liquid level height value H1 of the alkali solution foam and the cleaning alkali solution in the circulation tank.

[0066] The differential pressure level gauge 2 is arranged inside the circulation tank 11, and its measuring range can also be configured to be 0-5m. The differential pressure level gauge is an instrument that uses the static pressure difference of the fluid to measure the liquid level. It determines the liquid level by measuring the pressure difference between the upper and lower ends of the liquid. The differential pressure level gauge can be installed at the bottom of the circulation tank. The differential pressure level gauge is used to measure the liquid level of the cleaning alkali solution in the circulation tank and output a second height. Because the mass of the alkali solution foam is relatively light, the second height output by the differential pressure level gauge 2 is not affected by the alkali solution foam, and the measurement result of the differential pressure level gauge 2 is the liquid level height value H2 of the cleaning alkali solution.

[0067] The control terminal 3 is connected to the radar level gauge and the differential pressure level gauge, and the control terminal is used to obtain the first height and the second height; the amount of alkali solution foam generated is determined according to the difference between the first height and the second height. It can be understood that the first height is the height of the alkali solution foam, and the second height is the height of the cleaning alkali solution, so the actual height value H3 of the alkali solution foam can be obtained by using the difference between the two level gauges, which can objectively reflect the amount of alkali solution foam generated in the circulation tank, that is, H3 = H1-H2. When the amount generated is greater than the preset value, it means that the alkali solution foam is large and there is a risk of overflowing the circulation tank, and then a defoaming signal is output to the defoaming device 4.

[0068] The defoaming device 4 is connected to the control terminal. When receiving the defoaming signal, the defoaming device is used to deliver the defoaming agent to the circulation tank so that the alkali solution foam is eliminated in time. Figure 5 , Figure 5 The defoaming device 4 may include a pump group, the inlet of the pump group is connected to the storage tank containing the defoaming agent, and the outlet is connected to the circulation tank. After the defoaming agent is transported to the circulation tank by the defoaming device, the defoaming agent can be eliminated in time to prevent it from overflowing the circulation tank. The pump group includes a pump, a control valve and a first pipeline. The first pipeline connects the storage tank and the circulation tank. The horizontal height of the storage tank is greater than the horizontal height of the circulation tank. The control valve is installed on the first pipeline. When the defoaming signal is received, the control valve and the pump are opened, and the defoaming agent in the storage tank is pumped into the circulation tank for defoaming.

[0069] In practical applications, when the defoaming agent is directly pumped to the circulation tank, the contact area between the defoaming agent and the alkali solution foam is small, resulting in low defoaming efficiency. Based on this, in a specific embodiment, the defoaming device includes an atomizing component.

[0070] The atomizing assembly includes a pump group and an atomizing nozzle. The inlet of the pump group is connected to a storage tank containing a defoaming agent. The inlet of the atomizing nozzle is connected to the outlet of the pump group, and the outlet of the atomizing nozzle is connected to a circulation tank. The atomizing nozzle is used to atomize the defoaming agent pumped by the pump group. The defoaming agent is atomized by the atomizing nozzle to increase the contact area between the defoaming agent and the alkali solution foam and improve the defoaming efficiency. Of course, a moving assembly can also be set on the top of the circulation tank, and the atomizing nozzle is installed on the moving assembly. When implementing atomizing defoaming, the moving assembly is controlled to move back and forth periodically to further increase the contact area between the defoaming agent and the alkali solution foam.

[0071] In practical applications, due to the high viscosity of the defoamer itself, the defoamer load is large when pumped by a pump group, and the pump group needs to be frequently started and stopped to transport the defoamer, which can easily cause damage to the pump group and high equipment consumption. Based on this, the embodiment of the present invention provides another method for adding the defoamer, please refer to Figure 6 , Figure 6 It is a schematic diagram of the structure of the atomizing assembly. The atomizing assembly includes an atomizing nozzle 19, a first pipe 20, a first valve 21, a second pipe 22, and a second valve 23. The atomizing nozzle can be configured as a mixer, the first valve can be configured as a pneumatic flap valve, the second valve can be configured as a pneumatic ball valve, one end of the first pipe is connected to a storage tank containing a defoaming agent, and the other end is equipped with an atomizing nozzle. The first valve is installed on the first pipe, and the first valve is used to control the flow state of the defoaming agent in the first pipe. One end of the second pipe is connected to the compressed air network 24, and the other end is connected to the atomizing nozzle 19; the second valve is installed on the second pipe, and the second valve is used to control the flow state of compressed air in the second pipe. The inlet of the first pipeline is connected to the storage tank containing the defoamer, and the storage tank is placed at a high place so that the horizontal height of the storage tank is greater than the horizontal height of the circulation tank. When the defoamer is added, the first valve 21 and the second valve 23 are opened. After the second valve 23 is opened, the compressed air flows to the atomizing nozzle 19, and the defoamer can be driven to flow into the circulation tank under the action of the compressed air; at the same time, the defoamer is atomized by compressed air, and the atomized particles with a diameter of 200 microns are sprayed at a high speed, and the contact area with the alkali solution foam is increased, and the defoamer is quickly defoamed. Since the introduction of compressed air can make the diameter of the defoamer atomized smaller, the second defoamer addition method is preferred.

[0072] It should be noted that the compressed air can cause the defoaming agent to flow into the circulation tank, thereby reducing the configuration of the pump, eliminating the need to frequently start and stop the pump group, and improving the stability and reliability of the defoaming device operation.

[0073] The defoaming control system also includes a tank level gauge 25 with a range of 0-5m. The tank level gauge 25 can be set as a differential pressure level gauge or a radar level gauge, which can measure the defoaming agent level in the tank. The tank level gauge 25 is connected to the control terminal, and is used to measure the defoaming agent level in the tank and output the third height to the processing terminal. When the tank is configured as a ton barrel, it is preferred that a radar level gauge is used to measure the defoaming agent level.

[0074] In practical applications, the radar level meter is affected by the humidity of the environment during operation, and condensation usually occurs at the detection probe, which affects its measurement accuracy. Based on this, in a specific embodiment, the control system also includes a nozzle, a third pipe and a solenoid valve. The nozzle is arranged on the side of the radar level meter; one end of the third pipe is connected to the compressed air network, and the other end is connected to the nozzle; the solenoid valve is installed on the third pipe, and the solenoid valve is used to open when the surface of the radar level meter needs to be defogged to deliver compressed air to the nozzle. The blowing surface of the nozzle covers the entire detection probe of the radar level meter, which is connected to 5 bar compressed air and automatically controlled by a solenoid valve. Similar to the defoaming agent timing addition device, the time for opening and closing the compressed air is set, and the air knife formed by high-speed and high-pressure air is used to quickly blow away the water mist that is about to condense, prevent the condensation of water vapor on the radar level meter probe, and ensure the stability and reliability of the monitoring of the amount of alkali foam generated.

[0075] See also Figure 7 , Figure 7The electrical structure diagram of the foam elimination control system. The control terminal 3 includes a remote station 26, a PLC 27 and a host computer 28 connected in sequence to realize remote control of the control system. The following is an overall description of the work flow of strip cleaning. After the strip enters the cleaning section, it first enters the alkali brush tank. The alkali brush circulation pump sprays the alkali solution with a temperature of 60°C and a pressure of 0.25MPa onto the upper and lower surfaces of the strip. The brush roller scrubs to clean the oil, dust and other impurities on the surface of the strip. Then the squeeze roller squeezes out the cleaning alkali solution. The strip enters the electrolytic tank for electrolytic cleaning. The excess alkali solution flows back to the circulation tank containing the alkali solution through the reflux pipe at the bottom of the alkali brush tank. The alkali solution in the alkali brush circulation tank is circulated internally by the filter circulation pump and the magnetic filter circulation pump to filter out the oil, iron powder and impurities. The alkali pump transports the alkali solution in the concentrated alkali tank to the circulation tank to ensure the concentration of the cleaning alkali solution. The defoamer pump group pumps the defoamer into the alkali brush circulation tank for defoaming. The alkali solution in the electrolytic cell is also pumped in by the alkali pump. The two electrodes electrolyze the cleaning alkali solution to clean the oil, dust and impurities attached to the surface of the strip, and then the strip enters the water brush tank. The excess alkali solution flows to the suction port of the alkali brush circulation pump through the reflux pipe and continues to participate in the circulation. The strip enters the water brush tank, and the water brush circulation pump sprays water through the nozzle to the upper and lower surfaces of the strip. The brush roller scrubs to clean the residual alkali solution and impurities on the surface of the strip, and the squeeze roller squeezes out the water on the surface of the strip. The strip enters the water washing section, and the excess water flows back to the water brush circulation tank. The strip enters the water washing tank, and the front and rear cleaning pumps spray water through the nozzle to the upper and lower surfaces of the strip, and pump it into the water washing tank for circulation. The high-pressure flushing pump pumps water into the nozzle for the final high-pressure flushing. The squeeze roller squeezes out the water on the surface of the strip, and the strip enters the drying box. The exhaust fan discharges the alkali vapor in the alkali brush tank, electrolytic cell, and alkali brush circulation tank and the water vapor in the water brush tank and water washing tank out of the factory.

[0076] Based on the same technical concept as the control system, the present invention also provides a control method for the foam elimination control system, see Figure 8 , Figure 8 is a flow chart of the control method. The control system includes a radar level gauge, a differential pressure level gauge, a control terminal and a defoaming device. The radar level gauge is arranged on the top of a circulation tank containing cleaning alkali solution, and the differential pressure level gauge is arranged inside the circulation tank. The radar level gauge, the differential pressure level gauge and the defoaming device are all connected to the control terminal. The control method can be applied to the control terminal to implement defoaming control of alkali solution foam. The control method includes:

[0077] S11, obtaining a first height at which the radar level meter measures the height of the alkali solution foam in the circulation tank, and a second height at which the differential pressure level meter measures the level of the cleaning alkali solution in the circulation tank.

[0078] Specifically, the first height and the second height can be obtained through a preset period, and the first height and the second height are filtered based on the configured preset interval. If the first height and the second height are both in their corresponding preset intervals, it means that the data collection is correct; otherwise, re-collection is performed to determine whether the first height and the second height obtained are accurate. The first height and the second height can be obtained by configuring corresponding variables, the first height is recorded as H1, and the second height is recorded as H2. After obtaining the first height and the second height, step S12 is entered.

[0079] S12, determining the amount of alkali solution foam generated according to the difference between the first height and the second height.

[0080] Specifically, the amount of alkali liquid foam can be directly represented by the height value, H3 = H1-H2, H3 is the amount of alkali liquid foam generated; it can also be represented by volume, the inner diameter of the circulation tank can be measured, and the amount of alkali liquid foam generated can be obtained based on its inner diameter and height value H3. After determining the amount of alkali liquid foam generated, step S13 is entered.

[0081] S13, when the generated amount is greater than a preset value, a defoaming signal is output to the defoaming device to control the defoaming device to deliver the defoaming agent to the circulation tank, so that the alkali solution foam is eliminated in time.

[0082] Specifically, the preset value can be set based on actual needs, for example, the alkali solution foam approaches the height of 0.2-0.4m of the filling port of the circulation tank. When the generated amount is greater than the preset value, it indicates that the alkali solution foam is at risk of overflowing the circulation tank, and a defoaming signal is output to the defoaming device. When the defoaming device receives the defoaming signal, the defoaming agent can be transported to the circulation tank through the pump group to eliminate the alkali solution foam in the circulation tank in time.

[0083] In actual applications, if the amount of defoamer added is too large, the alkali solution foam in the circulation tank is well eliminated. However, due to the pollution of the cleaning alkali solution by adding excessive defoamer, the cleaning effect of the steel strip is poor, and the residue cannot form a good oxide film during annealing in the furnace, resulting in product quality defects. At the same time, excessive consumption of defoamer will increase the unit cost of the steel strip and reduce the profitability of the enterprise. If the amount of defoamer added is small, the foam generated by the alkali solution circulation cannot be eliminated in time, and the foam will carry a large amount of alkali solution to overflow, increasing the pressure of environmental protection indicators and wasting alkali solution. Based on this, in a specific embodiment, after outputting the defoaming signal to the defoaming device, the method also includes:

[0084] S14. In the first time period, the defoaming device is controlled to quantitatively deliver the defoaming agent to the circulation tank according to the preset addition amount, and the first average consumption of the defoaming agent is obtained. The first average consumption is the consumption of the defoaming agent generated by the quantitative delivery of the defoaming agent per unit time. The total amount of quantitative delivery of the defoaming agent in the first time period can be measured and divided by the duration of the first time period to obtain the first average consumption. It can be understood that the delivery amount of the defoaming agent can be controlled by the pump group, for example, by controlling the single operation time of the pump group through a time relay, which will not be described in detail here.

[0085] S15. In the second period, the defoaming device is controlled to deliver a corresponding dose of defoaming agent to the circulation tank according to the generated amount, and a second average consumption of the defoaming agent is obtained. Based on the corresponding relationship between the generated amount and the corresponding dose of the defoaming agent delivered, the current dose can be determined in the corresponding relationship based on the current generated amount, and the defoaming agent can be delivered to the circulation tank based on the current dose.

[0086] S16. Determine the target delivery amount of the defoamer according to the first average consumption and the second average consumption, wherein the target delivery amount is the minimum dosage of the defoamer to ensure that the alkali solution foam does not overflow the circulation tank. The first average consumption is the consumption of the defoamer added regularly and quantitatively; the second average consumption is the consumption added based on the amount of alkali solution foam generated. Through multiple parameter optimizations, the best parameters suitable for the production of this unit are found. The first average consumption and the second average consumption can be input into the dosage optimization model, and the target delivery amount of the defoamer can be obtained based on the output result of the model.

[0087] In order to further improve the metering accuracy of the generated amount, the control method also includes:

[0088] Determine whether the cleaning alkali solution in the circulation tank is heated to exceed the temperature threshold. When the cleaning alkali solution is heated to exceed the temperature threshold, it means that the steam evaporating upward from the cleaning alkali solution may cover the surface of the radar level meter, and then the purge signal is output to control the solenoid valve to open, so that the nozzle connected to the solenoid valve purges the radar level meter with compressed air for defog. On the contrary, when the cleaning alkali solution is not heated to exceed the temperature threshold, it is monitored and a thermometer can be set in the circulation tank for monitoring.

[0089] The conventional method of delivering the defoaming agent to the circulation tank results in a small contact area between the defoaming agent and the alkali solution foam, resulting in a low defoaming efficiency. Based on this, in a specific embodiment, after outputting the defoaming signal to the defoaming device, the method further includes:

[0090] The first valve on the first pipe is opened to the first opening, wherein the first pipe is a pipe on the defoaming device connecting the atomizing nozzle and the storage tank containing the defoaming agent; the second valve on the second pipe is opened to the second opening, so that the defoaming agent delivered to the circulation tank is atomized to the target state, wherein the second pipe is a pipe connecting the compressed air and the atomizing nozzle. The target state is a state where the defoaming agent is atomized to a diameter below the preset diameter, and the atomization effect of the defoaming agent can be improved by compressed air, thereby improving the defoaming efficiency.

[0091] In order to further monitor the defoaming agent, the control method also includes: obtaining the third height for level measurement of the defoaming agent in the storage tank; the height threshold can be set based on actual needs, and when the third height is greater than or equal to the height threshold, it means that the defoaming agent is sufficient. On the contrary, when the third height is lower than the height threshold, it means that the defoaming agent needs to be replenished in time, and the defoaming agent liquid level alarm signal is output. The liquid level alarm signal can remind on-site personnel to replenish the defoaming agent to the storage tank or replace the ton barrel.

[0092] See also Fig. 9 , Fig. 9 This is a control model distribution diagram of the foam elimination control system. The foam detection liquid level, alkali solution detection liquid level, defoamer liquid level and the set defoamer addition time are obtained, and the obtained data are input into the defoamer addition judgment model. Based on the judgment model, it is determined whether the defoamer needs to be added to the circulation tank. When the defoamer needs to be added, the second valve (or pneumatic valve) of the defoamer device is controlled to open.

[0093] The technical solution provided in the embodiments of the present invention has at least the following technical effects or advantages:

[0094] 1. The technical solution includes a radar level gauge, a differential pressure level gauge, a control terminal and a defoaming device. The radar level gauge measures the height of the alkali solution foam in the circulation tank to obtain a first height, and the differential pressure level gauge measures the level of the cleaning alkali solution in the circulation tank to obtain a second height; the amount of alkali solution foam generated is accurately obtained according to the difference between the first height and the second height; when the amount generated is greater than a preset value, it indicates that there is a risk of the alkali solution foam overflowing the circulation tank, and a defoaming signal is output to the defoaming device to control the defoaming device to deliver the defoaming agent to the circulation tank, so that the alkali solution foam is eliminated in time. The technical solution of the embodiment of the present invention can pump the defoaming agent based on the accurate amount of alkali solution foam generated, thereby effectively preventing the cleaning alkali solution from overflowing from the top of the circulation tank. At the same time, precise control of the defoaming agent pumping is achieved, saving the amount of defoaming agent used.

[0095] 2. The control system has high stability and precise control, which can achieve optimal control of defoamer consumption, effectively eliminate the foam generated during the circulation of alkali solution, and save the amount of defoamer and flushing liquid. The technical solution of foam detection and elimination in the circulation tank can reduce the consumption of cleaning alkali solution and generate benefits of 6.547 million yuan per year, of which the control model accounts for about 10% of the entire project, that is, an annual benefit of 654,700 yuan, so it is conducive to large-scale industrial application.

[0096] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0097] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (modules, systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0098] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0099] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0100] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0101] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A foam elimination control system, characterized in that: The system comprises: A radar level gauge is disposed on the top of a circulation tank containing cleaning alkali solution, and is used to measure the height of alkali solution foam in the circulation tank and output a first height; A differential pressure level gauge is arranged inside the circulation tank, and is used to measure the level of the cleaning alkali solution in the circulation tank and output a second height; a control terminal connected to the radar level gauge and the differential pressure level gauge, the control terminal being used to obtain the first height and the second height; determining the amount of alkali solution foam generated according to the difference between the first height and the second height, and outputting a defoaming signal when the amount of foam generated is greater than a preset value; A defoaming device is connected to the control terminal and is used to deliver a defoaming agent to the circulation tank when receiving the defoaming signal, so that the alkali solution foam is eliminated in time.

2. The foam elimination control system according to claim 1, characterized in that: The defoaming device comprises: An atomizing assembly, wherein the inlet of the atomizing assembly is connected to a storage tank containing a defoaming agent, and the outlet of the atomizing assembly is connected to the circulation tank. The atomizing assembly is used to atomize the defoaming agent output from the storage tank.

3. The foam elimination control system according to claim 2, characterized in that: The atomizing assembly comprises: Atomizing nozzle; A first pipe, one end of which is connected to the storage tank and the other end of which is equipped with the atomizing nozzle; A first valve, installed on the first pipeline, the first valve is used to control the flow state of the defoaming agent in the first pipeline; A second pipeline, one end of which is connected to the compressed air network, and the other end of which is connected to the atomizing nozzle; The second valve is installed on the second pipeline, and the second valve is used to control the flow state of compressed air in the second pipeline.

4. The foam elimination control system according to claim 1, characterized in that: The system further comprises: A tank level gauge is connected to the control terminal, and is used to measure the level of the defoaming agent in the tank and output a third height to the processing terminal.

5. The foam elimination control system according to claim 1, characterized in that: The system further comprises: A nozzle, arranged on the side of the radar level gauge; A third pipeline, one end of which is connected to the compressed air network and the other end of which is connected to the nozzle; A solenoid valve is installed on the third pipeline, and the solenoid valve is used to open when it is necessary to defog the surface of the radar level gauge to deliver compressed air to the nozzle.

6. A control method for a foam elimination control system, characterized in that: The system comprises a radar level gauge, a differential pressure level gauge, a control terminal and a defoaming device, wherein the radar level gauge is arranged on the top of a circulation tank containing cleaning alkali solution, the differential pressure level gauge is arranged inside the circulation tank, and the radar level gauge, the differential pressure level gauge and the defoaming device are all connected to the control terminal; the method comprises: Acquire a first height at which the radar level gauge measures the height of the alkali solution foam in the circulation tank, and a second height at which the differential pressure level gauge measures the level of the cleaning alkali solution in the circulation tank; determining the amount of the alkali solution foam generated according to the difference between the first height and the second height; When the generated amount is greater than a preset value, a defoaming signal is output to the defoaming device to control the defoaming device to transport the defoaming agent to the circulation tank, so that the alkali solution foam is eliminated in time.

7. The control method of the foam elimination control system according to claim 6, characterized in that: After outputting the defoaming signal to the defoaming device, the method further includes: In a first time period, the defoaming device is controlled to quantitatively deliver the defoaming agent to the circulation tank according to a preset addition amount, and a first average consumption of the defoaming agent is obtained; In a second time period, the defoaming device is controlled to deliver a corresponding dose of defoaming agent to the circulation tank according to the generated amount, and a second average consumption of the defoaming agent is obtained; The target delivery amount of the defoaming agent is determined according to the first average consumption and the second average consumption, wherein the target delivery amount is the minimum dosage of the defoaming agent to ensure that the alkali solution foam does not overflow the circulation tank.

8. The control method of the foam elimination control system according to claim 6, characterized in that: The method further comprises: Determining whether the cleaning alkali solution in the circulation tank is heated to a temperature exceeding a threshold value; If so, a purge signal is output to control the solenoid valve to open, so that the nozzle connected to the solenoid valve purges the radar level gauge with compressed air to defog.

9. The control method of the foam elimination control system according to claim 6, characterized in that: After outputting the defoaming signal to the defoaming device, the method further includes: Opening a first valve on a first pipeline to a first opening, wherein the first pipeline is a pipeline on the defoaming device connecting an atomizing nozzle and a storage tank containing a defoaming agent; The second valve on the second pipeline is opened to a second opening degree so that the defoaming agent delivered to the circulation tank is atomized to a target state, wherein the second pipeline is a pipeline connecting the compressed air and the atomizing nozzle.

10. The control method of the foam elimination control system according to claim 6, characterized in that: The method further comprises: Obtaining a third height for measuring the liquid level of the defoaming agent in the storage tank; When the third height is lower than a height threshold, a liquid level alarm signal of the defoaming agent is output.

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