A system and method for automatically adding an anti-foaming agent to a phosphate ester fire-resistant oil system

Abstract

The present invention provides a system and method for automatically adding an antifoaming agent to a phosphate ester fire-resistant oil system, belonging to the technical field of phosphate ester fire-resistant oils. The system includes an antifoaming agent adding device, an antifoaming agent sampling device, a displacement testing device, and an antifoaming agent adding control system. The antifoaming agent adding device is fixed to the upper part of the return oil pipe on the return oil side of the oil tank. The bottom of the antifoaming agent adding device is no more than 1 cm away from the oil flow position of the return oil pipe. A filter screen is arranged at the bottom outlet of the antifoaming agent adding device. The first inlet of the antifoaming agent adding device is hermetically connected to the outlet of the antifoaming agent sampling device, and the second inlet of the antifoaming agent adding device is hermetically connected to the outlet of the pressurizing device. The displacement testing device floats on the liquid surface of the antifoaming agent in the antifoaming agent adding device. The antifoaming agent adding control system is connected to the antifoaming agent sampling device, the pressurizing device, and the displacement testing device. The present invention solves the problem that the antifoaming agent cannot form a stable and uniform dispersion system in the oil product, and cannot achieve the antifoaming effect or the effect is poor.

Description

Technical Field

[0001] The present invention belongs to the technical field of phosphate ester fire-resistant oil, and particularly relates to a system and method for automatically adding an anti-foaming agent to a phosphate ester fire-resistant oil system. Background Art

[0002] The main component of phosphate ester fire-resistant oil is triaryl phosphate fire-resistant oil, which has excellent heat resistance, fire prevention and lubrication properties. With the continuous increase of the power of generator sets, the oil pressure of the steam turbine governing system also increases accordingly. To prevent fires caused by high-pressure oil leakage, phosphate ester fire-resistant oil has been widely used as the control fluid for steam turbine governing systems. The foam characteristic is an important index of phosphate ester fire-resistant oil, which is used to evaluate the tendency and stability of phosphate ester fire-resistant oil to form foam. At present, the phenomenon of excessive foam characteristics of phosphate ester fire-resistant oil in power plants is serious. According to statistics, in the current supervision of phosphate ester fire-resistant oil in power plants, the qualified rate of the foam characteristics of phosphate ester fire-resistant oil is only 39.2%, and the unqualified rate reaches 60.8%. If the tendency is greater than 400 ml, it is defined as seriously unqualified, and the seriously unqualified rate reaches 15.4%. The problem of unqualified foam characteristics of phosphate ester fire-resistant oil has caused great troubles to many users of phosphate ester fire-resistant oil.

[0003] Among the current treatment measures for excessive foam characteristics of oil products, the most common one is to add an anti-foaming agent. The common type of anti-foaming agent is silicone oil. Compared with oil products, silicone oil has a very high viscosity and will affect the air release performance of oil products. The method of adding an anti-foaming agent is to take 5L - 10L of oil from the oil system, stir it with the anti-foaming agent to form a mother liquor, and then add it to the fuel tank for defoaming. However, due to the high viscosity of the anti-foaming agent and the obvious difference in molecular structure from oil products, it is not easy to form a uniform dispersion system in the oil. Moreover, during the operation of the oil system, part of the anti-foaming agent is prone to agglomeration and floats on the upper part of the phosphate ester fire-resistant oil fuel tank. Part of the anti-foaming agent in the pipeline, due to agglomeration, has a very high viscosity and cannot pass through the filter element of the oil system, but adheres to the filter element wall, increasing the resistance of the filter element and resulting in a filter element differential pressure alarm. With the replacement of the filter element, the agglomerated anti-foaming agent leaves the oil system. Eventually, the result is that the anti-foaming agent agglomerated on the top of the fuel tank cannot be dispersed into the oil and cannot play a defoaming effect. The anti-foaming agent that enters the system circulation and agglomerates leaves the oil system with the replacement of the filter element, resulting in poor or even no effect after the anti-foaming agent is added to the system.

[0004] For phosphate ester fire-resistant oil, when the foam characteristics exceed the standard, on the one hand, more air can be entrapped into the system, accelerating the deterioration of the oil product. On the other hand, the good stability of the foam will also lead to poor air release value of the oil product, resulting in unqualified air release value index. After a large number of air bubbles enter the system, as the pressure of the phosphate ester fire-resistant oil system continues to increase, when the pressure increases, the air bubbles in the oil will burst, generating a large amount of heat and energy, accelerating the deterioration of the oil product, and can damage the metal surface, thereby accelerating the corrosion of the servo valve. There is also a large amount of oil containing air entering the oil pump, resulting in vibration of the pump and affecting the output capacity of the pump.

[0005] Therefore, it is of great significance to study the defoamer applicable to phosphate ester fire-resistant oil and its addition system. Summary of the Invention

[0006] In order to overcome the problems in the prior art that the defoamer in phosphate ester fire-resistant oil is added in the form of mother liquor, and due to its own characteristics, the defoamer is prone to agglomeration, and then gradually follows the filter element replacement or floats on the top of the oil tank, and cannot form a stable and uniform dispersion system in the oil product, and cannot achieve the defoaming effect or the effect is poor, the present invention provides a system and method for automatically adding defoamer to a phosphate ester fire-resistant oil system.

[0007] To achieve the above object, the present invention provides the following technical solutions: A system for automatically adding defoamer to a phosphate ester fire-resistant oil system, including a defoamer adding device, a defoamer sampling device, a displacement testing device and a defoamer adding control system, wherein:

[0008] The defoamer adding device is fixed on the upper part of the return oil pipe on the return oil side of the oil tank. The bottom of the defoamer adding device is not more than 1 cm away from the oil flow position of the return oil pipe. A filter screen is arranged at the bottom outlet of the defoamer adding device. The first inlet of the defoamer adding device is hermetically connected to the outlet of the defoamer sampling device. The second inlet of the defoamer adding device is hermetically connected to the outlet of the pressurizing device. The displacement testing device floats on the liquid surface of the defoamer in the defoamer adding device;

[0009] The defoamer adding control system is connected to the defoamer sampling device for controlling the opening and closing of the defoamer sampling device and the sampling amount of the defoamer;

[0010] The defoamer adding control system is connected to the pressurizing device for controlling the opening and closing of the pressurizing device and the pressure applied by the pressurizing device to the liquid surface of the defoamer;

[0011] The defoamer adding control system is connected to the displacement testing device for controlling the opening and closing of the displacement testing device.

[0012] Further, the aperture of the filter screen arranged at the bottom outlet of the defoamer adding device is 0.5 μm - 3 μm.

[0013] Further, the defoamer adding device is a container surrounded by stainless steel plates arranged around, a sealable lid at the top, and a stainless steel sintered filter screen with a bottom aperture of 0.5 μm - 3 μm. The first inlet and the second inlet of the defoamer adding device are arranged on the sealable lid at the top of the defoamer adding device.

[0014] Further, the displacement testing device is connected to the defoamer adding control system wirelessly or by wire; when it is a wired connection, the connection line passes through the third inlet of the defoamer adding device and is sealed at the third inlet. The third inlet is arranged on the sealable lid at the top of the defoamer adding device.

[0015] Further, the defoamer injection device includes a defoamer storage device. The outlet of the defoamer storage device is connected to the first inlet of the defoamer addition device through a pipeline. A micro liquid pump, a first solenoid valve, and a flow sensor are arranged on the pipeline. The micro liquid pump, the first solenoid valve, and the flow sensor are all connected to the defoamer addition control system.

[0016] Further, the pressurizing device includes a micro compressed air pump. The outlet of the micro compressed air pump is connected to the second inlet of the defoamer addition device through a pipeline. A second solenoid valve and a pressure sensor are arranged on the pipeline. The second solenoid valve and the pressure sensor are all connected to the defoamer addition control system.

[0017] Further, the displacement testing device is a displacement sensor, and the displacement sensor is connected to the defoamer addition control system.

[0018] Further, the defoamer is a silicone defoamer. Based on the weight of the phosphate ester fire-resistant oil in the fuel tank, the addition dosage of the silicone defoamer is 10 mg / kg - 30 mg / kg.

[0019] The present invention also provides a method for automatically adding a defoamer to a phosphate ester fire-resistant oil system. Using the above-mentioned system for automatically adding a defoamer to a phosphate ester fire-resistant oil system, the specific steps of the method are as follows:

[0020] S1. The defoamer addition control system starts the defoamer injection device. The defoamer injection device adds a defoamer with a quantitative volume into the defoamer addition device, and the defoamer addition control system closes the defoamer injection device.

[0021] S2. The defoamer addition control system starts the pressurizing device. The pressurizing device pressurizes the liquid level of the defoamer in the defoamer addition device to 300 kPa ± 50 kPa and keeps the pressure constant during the defoamer addition process.

[0022] S3. Under the pressurizing action of the pressurizing device, all the defoamer in the defoamer addition device is pressed into the fuel tank through the bottom filter screen. When the displacement of the displacement testing device along with the liquid level drop of the defoamer reaches the height of the defoamer in the defoamer addition device, the defoamer addition control system controls the pressurizing device to relieve pressure and close.

[0023] S4. The defoamer addition control system determines whether it is necessary to add defoamer to the defoamer addition device again according to the set number of times of releasing the defoamer by the defoamer addition device. If necessary, repeat S1 - S4. If not, close the defoamer addition control system.

[0024] Furthermore, the height of the defoamer in the defoamer addition device is calculated based on the density of the defoamer, the bottom area of the defoamer addition device, and the mass of the defoamer added to the defoamer addition device each time. The specific calculation method is as follows:

[0025] l = m / ( ρ · s )

[0026] Wherein, l is the displacement distance of the displacement test device; ρ is the density of the defoamer; s is the bottom area of the defoamer addition device; m is the mass of the defoamer.

[0027] Compared with the prior art, the present invention has at least the following beneficial effects:

[0028] The present invention provides a system for automatically adding a defoamer to a phosphate ester fire-resistant oil system. The system integrates a defoamer addition device, a defoamer sampling device, a pressurizing device, a displacement test device, and a defoamer addition control system, realizing the automatic addition and uniform dispersion of the defoamer. The defoamer addition control system precisely controls the sampling amount, pressurizing pressure, and addition process of the defoamer, ensuring the effective distribution of the defoamer in the oil system, and at the same time avoiding the cumbersome and error of manual operation. The present invention fixes the defoamer addition device on the return oil side inside the fuel tank, which can ensure that the defoamer particles quickly diffuse to the entire fuel tank along with the return oil, improving the defoaming efficiency. At the same time, the bottom of the defoamer addition device is relatively close to the oil flow position on the return oil side inside the fuel tank, which helps to increase the defoamer concentration gradient and promote the uniform distribution of the defoamer particles, solving the problem that after the defoamer is added to the oil system in the form of a mother liquor, the defoamer is prone to agglomeration due to its own characteristics, and then gradually follows the filter element replacement or floats on the top of the fuel tank, unable to form a stable and uniform dispersion system in the oil product, and unable to achieve the defoaming effect or the effect is poor.

[0029] Preferably, the defoamer adding device is a container composed of a stainless steel plate and a stainless steel sintered filter screen, ensuring the corrosion resistance and sealing performance of the device. The aperture of the bottom stainless steel sintered filter screen is selected to be 0.5μm - 3μm, enabling the defoamer particles to enter the oil system evenly and stably. This particle size control is crucial for the dispersion and effectiveness of the defoamer in the oil. Smaller particles can be more evenly distributed in the oil, forming a more stable colloid, thereby improving the defoaming effect. Brownian motion indicates that particles smaller than a certain particle size will move randomly in the solution. The defoamer particles of the present invention can perform effective Brownian motion in the oil, form a stable colloid, and quickly diffuse throughout the oil system. This diffusion ability helps the defoamer to be evenly distributed in the oil and improve the defoaming efficiency. Moreover, the concentration of the defoamer added to the oil system is usually relatively low, such as 10mg / kg - 30mg / kg. The defoamer particles within this concentration range are not prone to agglomeration after being dispersed in the oil. At the same time, the particle size of 0.5μm - 3μm also helps to maintain the stability of the particles and prevent them from aggregating with each other to form larger particles.

[0030] Preferably, the defoamer injection device realizes precise injection and flow control of the defoamer through the combination of a micro liquid pump, a solenoid valve, and a flow sensor. The connection of these components to the defoamer adding control system enables the injection process to be automated without manual intervention.

[0031] Preferably, the pressurizing device is a combination of a micro-compressed air pump, a three-way solenoid valve, and a pressure sensor, which realizes precise pressurization and pressure control of the defoamer liquid level. By maintaining a constant pressure, the diffusion of defoamer particles in the oil system can be accelerated, improving the defoaming effect.

[0032] Preferably, the displacement test device is connected to the defoamer adding control system. Whether it is a wireless or wired connection, it ensures that the displacement test device can accurately and real-time transmit the information on the change of the defoamer liquid level to the defoamer adding control system, thereby precisely controlling the defoamer adding process. The wired connection is sealed through the third inlet, ensuring the overall sealing performance of the system. The displacement test device is a displacement sensor, which can accurately measure the change of the defoamer liquid level and transmit this information to the defoamer adding control system in real time. This design ensures the accuracy and timeliness of defoamer addition, avoiding problems such as over-addition or under-addition.

[0033] Preferably, the defoamer used is a silicone-based defoamer. The silicone-based defoamer has excellent defoaming effect and stability, and has no impact on the air release value of phosphate ester fire-resistant oil, overcoming the problem in the prior art that the addition of a defoamer to phosphate ester fire-resistant oil affects the air release value of the oil product. At the same time, the present invention gives a reasonable dosage range, such as 10mg / kg - 30mg / kg, ensuring the defoaming effect while avoiding waste and pollution.

[0034] The present invention also provides a method for automatically adding an antifoaming agent to a phosphate ester fire-resistant oil system. This method details the specific steps of automatic antifoaming agent addition, including processes such as sample injection, pressurization, detection, and judgment. By precisely controlling the parameters and conditions of each step, the accuracy and effectiveness of antifoaming agent addition are ensured. At the same time, this method also considers the judgment of the number of antifoaming agent additions, realizing the continuous replenishment of the antifoaming agent and the long-term stable operation of the oil system.

[0035] Preferably, the present invention calculates the height of the antifoaming agent in the addition device based on parameters such as the density of the antifoaming agent, providing an accurate basis for the displacement distance of the displacement sensor. This design enables the antifoaming agent addition control system to more precisely control the addition amount of the antifoaming agent, avoiding problems of over-addition or under-addition. At the same time, it also improves the automation level and intelligent level of the system. Brief Description of the Drawings

[0036] Figure 1 It is a schematic structural diagram of a system for automatically adding an antifoaming agent to a phosphate ester fire-resistant oil system according to the present invention.

[0037] Figure 2 It is a schematic diagram of a filter screen.

[0038] In the figure, 1 is an antifoaming agent addition device; 2 is an antifoaming agent addition area; 3 is a displacement sensor; 4 is a flow sensor; 5 is a first solenoid valve; 6 is a micro liquid pump; 7 is an antifoaming agent storage device; 8 is a pressure sensor; 9 is a second solenoid valve; 10 is a micro air compressor; 11 is an air filter; 12 is an antifoaming agent addition control system; 13 is a fuel tank; 14 is a return pipe; 15 is a filter screen. Detailed Embodiments

[0039] The present invention will be further described below in conjunction with the drawings and detailed embodiments.

[0040] As Figure 1 shown, the present invention provides a system for automatically adding an antifoaming agent to a phosphate ester fire-resistant oil system, including an antifoaming agent addition device 1, an antifoaming agent sample injection device, a pressurization device, a displacement testing device, and an antifoaming agent addition control system 12. The antifoaming agent addition control system 12 is connected to the antifoaming agent sample injection device, the pressurization device, and the displacement testing device, wherein:

[0041] The defoamer is filled in the defoamer addition area 2 of the defoamer addition device 1. The defoamer addition device 1 is placed in the oil tank 13, fixed on the oil return side of the oil tank 13, and located above the oil return pipe 14. The distance from the bottom of the defoamer addition device 1 to the oil flow position of the oil return pipe 14 does not exceed 1 cm. The outlet of the defoamer addition device 1 is set at the bottom. The oil flow rate on the oil return side of the oil tank 13 is high. After the defoamer in the defoamer addition device 1 enters the oil system from the bottom outlet, it will quickly migrate to other areas of the oil tank 13 along with the oil flow on the oil return side. There is an obvious concentration difference between the bottom area of the defoamer addition device 1 and the nearby areas, which is convenient for the diffusion of the defoamer.

[0042] The first inlet of the defoamer addition device 1 is hermetically connected to the outlet of the defoamer sampling device for introducing a set mass of defoamer into the defoamer addition device 1 under the control of the defoamer addition control system 12.

[0043] The second inlet of the defoamer addition device 1 is hermetically connected to the outlet of the pressurizing device for pressurizing the upper liquid level of the defoamer under the control of the defoamer addition control system 12 to accelerate the diffusion of the defoamer into the oil system.

[0044] The displacement test device floats on the liquid surface of the defoamer in the defoamer addition device 1 for transmitting a signal indicating the completion of defoamer addition to the defoamer addition control system 12 through displacement testing. The displacement test device and the defoamer addition control system 12 can be connected wirelessly or by wire. When connected by wire, the connecting wire passes through the third inlet of the defoamer addition device 1 and is sealed at the third inlet.

[0045] As Figure 2 shown, a filter screen 15 is provided at the bottom outlet of the defoamer addition device 1. The aperture of the filter screen 15 is 0.5 μm - 3 μm for dispersing the defoamer into fine particles and entering the oil system. The defoamer fine particles with a particle size of 0.5 μm - 3 μm will perform random Brownian motion in the oil system to form a stable colloid. The smaller the colloid particles, the larger the diffusion coefficient, and the stronger the diffusion ability of the defoamer fine particles, and the less likely they are to agglomerate.

[0046] Preferably, the defoamer addition device 1 is a cylindrical container with stainless steel plates on all sides, a sealable lid on the top, and a stainless steel sintered filter screen with an aperture of 0.5 μm - 3 μm at the bottom. The first inlet, second inlet, and third inlet of the defoamer addition device 1 are provided on the top lid of the defoamer addition device 1. There is a fixing ring in the middle outside the four sides of the defoamer addition device 1. A 10 cm long fixing nut is welded on one side of the fixing ring. The defoamer addition device 1 is fixed at the outlet of the oil return side pipeline of the phosphate ester fire-resistant oil tank 13 through this nut.

[0047] Preferably, the defoamer feeding device includes a defoamer storage device 7. The outlet of the defoamer storage device 7 is connected to the first inlet of the defoamer adding device 1 through a pipeline. A micro liquid pump 6, a first electromagnetic valve 5 and a flow sensor 4 are arranged on the pipeline. The micro liquid pump 6, the first electromagnetic valve 5 and the flow sensor 4 are all connected to the defoamer adding control system 12.

[0048] Preferably, the pressurizing device includes a micro air compressor 10. The inlet of the micro air compressor 10 is connected to the atmosphere. The outlet of the micro air compressor 10 is connected to the second inlet of the defoamer adding device 1 through a pipeline for introducing air into the defoamer adding device 1 to apply pressure to the upper liquid level of the defoamer. A second electromagnetic valve 9 and a pressure sensor 8 are arranged on the pipeline. The second electromagnetic valve 9 and the pressure sensor 8 are all connected to the defoamer adding control system 12.

[0049] Preferably, the second electromagnetic valve 9 is a three-way electromagnetic valve. One opening of the three-way electromagnetic valve is connected to the atmosphere, and after adding a fixed amount of defoamer, the air in the defoamer adding device 1 can be released into the atmosphere.

[0050] Preferably, an air filter 11 is further arranged in front of the micro air compressor 10. The inlet of the air filter 11 is communicated with the atmosphere, and the outlet of the air filter 11 is communicated with the inlet of the micro air compressor 10 for filtering air.

[0051] Preferably, the displacement test device is a displacement sensor 3. The displacement sensor 3 floats on the defoamer liquid level. The displacement sensor 3 is connected to the defoamer adding control system 12.

[0052] Preferably, the defoamer is a silicone defoamer of model XPJ990 sold by Jiangsu Saiou Xinyue Defoamer Co., Ltd. or a silicone defoamer of model DJ-288 sold by Zhoushan Tiande New Materials Co., Ltd. Based on the weight of the phosphate ester fire-resistant oil in the fuel tank 13, the dosage of the silicone defoamer is 10mg / kg - 30mg / kg. After adding this defoamer to the phosphate ester fire-resistant oil, it not only has good defoaming effect, but also has no impact on the air release value of the phosphate ester fire-resistant oil.

[0053] When adding defoamer to the fuel tank 13 by using the above system for automatically adding defoamer to the phosphate ester fire-resistant oil system, the specific steps are as follows:

[0054] S1, start the defoamer adding control system 12, and set the liquid level pressure of the defoamer in the defoamer adding device 1, the density of the defoamer, the total mass of the defoamer to be added to the fuel tank 13, the mass of the defoamer added to the defoamer adding device 1 each time, the number of times of adding defoamer to the defoamer adding device 1, the bottom area of the defoamer adding device 1, and the displacement calculation formula of the displacement sensor 3.

[0055] In S2, the defoamer addition control system 12 starts the micro liquid pump 6, the first solenoid valve 5 and the flow sensor 4. According to the signal fed back by the flow sensor 4 to the defoamer addition control system 12, and the preset defoamer density and the mass of the defoamer to be added in S1, the volume of the defoamer to be added is obtained. After automatically adding the defoamer into the defoamer addition device 1, the defoamer addition control system 12 closes the micro liquid pump 6 and the first solenoid valve 5;

[0056] In S3, the defoamer addition control system 12 starts the pressure sensor 8, the second solenoid valve 9, and the micro air compressor 10. The micro air compressor 10 feeds air into the defoamer addition device 1 to reach the set liquid level pressure of the defoamer, and maintains the set pressure throughout the process of adding the defoamer;

[0057] Preferably, the set pressure is 300 kPa ± 50 kPa, which can not only ensure that the defoamer with extremely high viscosity can pass through the microporous filter smoothly, but also ensure that the processing technology of the defoamer addition device 1 is easy to implement;

[0058] In S4, the displacement sensor 3 feeds back the displacement of the defoamer liquid level drop to the defoamer addition control system 12. The system obtains the defoamer height according to the mass of the defoamer added each time, the bottom area of the defoamer addition device 1 and the displacement calculation formula (1). When the fed-back displacement reaches the calculated defoamer height, the defoamer addition control system 12 closes the micro air compressor 10 and opens the second solenoid valve 9 in the evacuation direction to discharge the air in the defoamer addition device 1;

[0059] The displacement calculation formula (1) is specifically as follows:

[0060] l = m / ( ρ · s )(1)

[0061] Wherein, l — is the displacement distance of the displacement sensor 3; ρ — is the density of the defoamer; s — is the bottom area of the defoamer addition device 1; m is the mass of the defoamer.

[0062] In S5, the defoamer addition control system 12 determines whether it is necessary to add defoamer to the defoamer addition device 1 again according to the set number of times of releasing the defoamer by the defoamer addition device 1. If necessary, repeat S1 - S5. If not, close the defoamer addition control system 12.

[0063] Example 1

[0064] In the system for automatically adding defoamer to the phosphate ester fire-resistant oil system, the aperture of the stainless steel sintered filter screen at the outlet of the defoamer adding device 1 is 0.5 μm, and the dosage of silicone defoamer is 10 mg / kg;

[0065] When using the system for automatically adding defoamer to the phosphate ester fire-resistant oil system of the present invention to add defoamer to the oil tank 13, the specific steps are as follows:

[0066] S1. Start the defoamer adding control system 12, and set the liquid level pressure of the defoamer in the defoamer adding device 1 to 250 kPa, the density of the defoamer to 1.030 g / cm 3 , the total amount of oil in the oil system to 1000 kg, the total mass of the defoamer to be added to the oil tank 13 to 10 g, the mass of the defoamer added to the defoamer adding device 1 each time to 10 g, the number of times of adding the defoamer to the defoamer adding device 1 to 1, and the bottom area of the defoamer adding device 1 to 4.7 cm 2 , the displacement calculation formula of the displacement sensor 3 l = m / ( ρ · s ) = 2.06 cm;

[0067] S2. The defoamer adding control system 12 starts the micro liquid pump 6, the first solenoid valve 5 and the flow sensor 4. According to the signal fed back by the flow sensor 4 to the defoamer adding control system 12, and the preset defoamer density and the mass of the defoamer to be added in S1, the volume of the defoamer to be added is obtained as 9.7 mL. After automatically adding the defoamer to the defoamer adding device 1, the defoamer adding control system 12 closes the micro liquid pump 6 and the first solenoid valve 5;

[0068] S3. The defoamer adding control system 12 starts the pressure sensor 8, the second solenoid valve 9 and the micro air compressor 10, applies a pressure of 250 kPa to the liquid level of the defoamer in the defoamer adding device 1, and maintains the set pressure throughout the defoamer adding process;

[0069] S4. The displacement sensor 3 feeds back the displacement of the liquid level of the defoamer dropping to the defoamer adding control system 12. The system obtains the height of the defoamer according to the mass of the defoamer added each time, the bottom area of the defoamer adding device 1 and the displacement calculation formula (1). When the fed-back displacement reaches the calculated height of the defoamer of 2.06 cm, the defoamer adding control system 12 closes the micro air compressor 10 and opens the drain direction of the second solenoid valve 9 to discharge the air in the defoamer adding device 1;

[0070] S5. The defoamer adding control system 12 determines that there is no need to add defoamer to the defoamer adding device 1 again according to the set number of times of releasing the defoamer from the defoamer adding device 1, and closes the defoamer adding control system 12.

[0071] Example 2

[0072] In the system for automatically adding defoamer to the phosphate ester fire-resistant oil system of the present invention, the aperture of the stainless steel sintered filter screen is 1.5 μm at the outlet of the defoamer adding device 1, and the adding dosage of the silicone defoamer is 20 mg / kg;

[0073] When using the system for automatically adding defoamer to the phosphate ester fire-resistant oil system of the present invention to add defoamer to the oil tank 13, the specific steps are as follows:

[0074] S1. Start the defoamer adding control system 12, and set the liquid level pressure of the defoamer in the defoamer adding device 1 to 350 kPa, the density of the defoamer to 1.00 g / cm 3 , the total oil volume of the oil system is 1500 kg, the total mass of the defoamer to be added to the oil tank 13 is 30 g, the mass of the defoamer added to the defoamer adding device 1 each time is 15 g, the number of times of adding the defoamer to the defoamer adding device 1 is 2, the bottom area of the defoamer adding device 1 is 4.7 cm 2 , and the displacement calculation formula of the displacement sensor 3 l = m / ( ρ · s ) = 3.19 cm;

[0075] S2. The defoamer adding control system 12 starts the micro liquid pump 6, the first solenoid valve 5 and the flow sensor 4. According to the signal fed back by the flow sensor 4 to the defoamer adding control system 12, and the preset defoamer density and the mass of the defoamer to be added in S1, the volume of the defoamer to be added is obtained as 15 mL. After automatically adding the defoamer to the defoamer adding device 1, the defoamer adding control system 12 closes the micro liquid pump 6 and the first solenoid valve 5;

[0076] S3. The defoamer adding control system 12 starts the pressure sensor 8, the second solenoid valve 9 and the micro air compressor 10, applies a pressure of 350 kPa to the liquid level of the defoamer in the defoamer adding device 1, and maintains the set pressure during the whole defoamer adding process;

[0077] S4. The displacement sensor 3 feeds back the displacement of the liquid level drop of the defoamer to the defoamer adding control system 12. The system obtains the defoamer height according to the mass of the defoamer added each time, the bottom area of the defoamer adding device 1 and the displacement calculation formula (1). When the fed-back displacement reaches the calculated defoamer height of 3.19 cm, the defoamer adding control system 12 closes the micro air compressor 10, opens the drain direction of the second solenoid valve 9, and discharges the air in the defoamer adding device 1;

[0078] S5. The defoamer addition control system 12 determines that the defoamer needs to be added to the defoamer addition device 1 again according to the number of times the defoamer addition device 1 releases the defoamer as set, and repeats S1 - S5 once.

[0079] Example 3

[0080] In the system for automatically adding defoamer to the phosphate ester fire-resistant oil system of the present invention, the aperture of the stainless steel sintered filter screen at the outlet of the defoamer addition device 1 is 3.0 μm, and the addition dosage of the silicone defoamer is 30 mg / kg.

[0081] When using the system for automatically adding defoamer to the phosphate ester fire-resistant oil system of the present invention to add defoamer to the fuel tank 13, the specific steps are as follows:

[0082] S1. Start the defoamer addition control system 12, and set the liquid level pressure of the defoamer in the defoamer addition device 1 to 300 kPa, the density of the defoamer to 0.990 g / cm 3 , the total amount of oil in the oil system to 1500 kg, the total mass of the defoamer to be added to the fuel tank 13 to 45 g, the mass of the defoamer added to the defoamer addition device 1 each time to 22.5 g, the number of times of adding the defoamer to the defoamer addition device 1 to 2, the bottom area of the defoamer addition device 1 to 7.1 cm 2 , and the displacement calculation formula of the displacement sensor 3 l = m / ( ρ · s ) = 3.17 cm;

[0083] S2. The defoamer addition control system 12 starts the micro liquid pump 6, the first solenoid valve 5 and the flow sensor 4. According to the signal fed back by the flow sensor 4 to the defoamer addition control system 12, and the preset defoamer density and the mass of the defoamer to be added in S1, the volume of the defoamer to be added is obtained as 23 ml. After automatically adding the defoamer to the defoamer addition device 1, the defoamer addition control system 12 closes the micro liquid pump 6 and the first solenoid valve 5.

[0084] S3. The defoamer addition control system 12 starts the pressure sensor 8, the second solenoid valve 9 and the micro air compressor 10, applies a pressure of 300 kPa to the liquid level of the defoamer in the defoamer addition device 1, and maintains the set pressure throughout the defoamer addition process.

[0085] S4. The displacement sensor 3 feeds back the displacement that decreases with the decline of the defoamer liquid level to the defoamer addition control system 12. The system obtains the defoamer height based on the mass of the defoamer added each time, the bottom area of the defoamer addition device 1, and the displacement calculation formula (1). When the feedback displacement reaches the calculated defoamer height of 3.17 cm, the defoamer addition control system 12 shuts down the micro-compressed air pump 10, opens the drain direction of the second solenoid valve 9, and discharges the air in the defoamer addition device 1;

[0086] S5. The defoamer addition control system 12 determines whether it is necessary to add defoamer to the defoamer addition device 1 again according to the set number of times for the defoamer addition device 1 to release defoamer, and repeats S1 - S5 once.

[0087] Analysis of the application results of the embodiment: During the implementation process, the smaller the pore size of the stainless steel sintered filter screen, the smaller the air pressure at the upper part, and the relatively slower the speed of the defoamer dispersing into the oil system. However, the defoamer droplets formed have a small particle size and good stability when dispersed in the oil. Within the above-mentioned pressure range and the pore size range of the stainless steel sintered filter screen, it can be ensured that the defoamer addition device 1 is easy to process and a stable colloidal solution is formed after the defoamer is dispersed, meeting the requirement that the droplet particle size of the defoamer in the phosphate ester fire-resistant oil is less than 4 μm, and it can perform Brownian motion in the phosphate ester fire-resistant oil to form a stable colloidal solution. When the pore size of the stainless steel sintered filter screen is 1.5 μm, the pressure is 350 kPa, and at the same time the area of the stainless steel sintered filter screen is 5 cm 2 ~7 cm 2 When it is, it can ensure that a stable colloid is formed after the defoamer is dispersed and a relatively fast addition speed can also be obtained. When this parameter is used in this addition system, the effect is optimal.

[0088] As an additive for phosphate ester fire-resistant oil, the defoamer should be used in the minimum amount under the condition of meeting the performance requirements. If the addition amount is too large, the concentration in the oil increases, which will reduce the stability of the formed colloidal solution, and too large an amount will reduce the autoignition point of the phosphate ester fire-resistant oil. If the pressure is too small, it will lead to too low a defoamer addition speed, and if the pressure is too large, it will increase the processing difficulty of the defoamer addition device.

[0089] The present invention screens the addition amount of the defoamer, detects the foam characteristics of the phosphate ester fire-resistant oil used in the power plant before and after adding defoamers with different addition amounts, and the change data of the air release value of the base oil before and after adding the defoamer. The detection results are shown in Table 1:

[0090] Table 1 Test results of oil samples before and after adding the defoamer alone

[0091]

[0092] Remarks: The main components of the phosphate ester fire-resistant oil and the base oil used in the 2# machine of the power plant are both tris(dimethylphenyl) phosphate, and the base oil is new phosphate ester fire-resistant oil;

[0093] It can be seen from Table 1 that the addition amount of 10 mg / kg of silicone defoamer can make the phosphate ester antiwear hydraulic oil for Power Plant No. 2 with seriously exceeding foam characteristics reach the qualified level; to judge whether the additive has an impact on the air release value of the phosphate ester antiwear hydraulic oil, silicone defoamer was added to the base oil with an air release value of 0.7 min, and the addition amount was 30 mg / kg. After the addition, the air release value of the base oil was detected again, and the detection result was 0.7 min, indicating that the defoamer not only has good defoaming effect, but also has no impact on the air release value of the phosphate ester antiwear hydraulic oil.

[0094] The present invention explores the influence of the defoamer on the key item stability of the phosphate ester antiwear hydraulic oil, and the specific detection process is as follows:

[0095] The base oil and the base oil containing additives were selected. After adjusting their moisture contents to the same level, a closed-cup aging test was carried out. During the aging test, samples were taken regularly to detect key items, analyze the change trend, and judge the influence of the additive.

[0096] Since the moisture content of the phosphate ester antiwear hydraulic oil is mostly stable at about 200 mg / L during the actual operation process, the moisture content in the closed-cup aging test conditions here is designed to be 200 mg / L ± 50 mg / L. The other conditions are the same as the standard requirements of DL / T1705-2017 "Determination Method for Closed-Cup Aging of Phosphate Ester Antiwear Hydraulic Oil". The key items detected regularly during the aging test for the phosphate ester antiwear hydraulic oil specifically include acid value, resistivity, and sludge precipitation detection.

[0097] The specifications of the copper wire catalyst used in the test are: Copper T1, with a purity of not less than 99.95%, a diameter of 1.03 mm, and a length of 330 mm, spun into a spiral shape with an outer diameter of 19 mm and a length of 38 mm.

[0098] The detection results are shown in Tables 2 to 4:

[0099] Table 2 Acid value detection results of the base oil with 30 mg / kg of silicone defoamer added during the 115 °C closed-cup aging test

[0100]

[0101] Table 3 Resistivity detection results of the base oil with 30 mg / kg of silicone defoamer added during the 115 °C closed-cup aging test

[0102]

[0103] Table 4 Sludge precipitation detection results of the base oil with 30 mg / kg of silicone defoamer added during the 115 °C closed-cup aging test

[0104]

[0105] Tables 2 to 4 show the changes in the acid value, resistivity, and sludge precipitation of the base oil after adding 30 mg / kg of silicone defoamer during aging. The results show that after adding 30 mg / kg of silicone defoamer, there is no impact on the stability of the base oil.

[0106] Combined with Tables 2 to 4, it can be seen that 30 mg / kg of silicone defoamer has no impact on the stability of phosphate ester fire-resistant oil. The dosage of the defoamer follows the principle of small dosage. Table 1 shows that the addition amount of 10 mg / kg of silicone defoamer can make the fire-resistant oil sample with seriously exceeding foam characteristics reach the qualified level, indicating that the addition dosage of 10 mg / kg can achieve the defoaming effect. The addition amount of 30 mg / kg does not affect the stability of phosphate ester fire-resistant oil, which can prove that the addition amount of 10 mg / kg will not affect the stability of phosphate ester fire-resistant oil either.

[0107] In summary, for the system and method for automatically adding defoamer to the phosphate ester fire-resistant oil system of the present invention, the defoamer adding device 1 is fixed at the pipeline outlet on the oil return side of the phosphate ester fire-resistant oil tank 13. Through the pressurizing device, the defoamer in the defoamer adding device 1 can be evenly dispersed in the phosphate ester fire-resistant oil system in the form of particles smaller than 3 μm, forming a stable colloid, achieving a good defoaming effect. At the same time, there is no need to prepare the mother liquor. Only the total amount of defoamer required needs to be calculated according to the total oil volume of the system, the calculated defoamer is put into the device, and then the device is directly placed near the oil return side outlet of the tank 13. The operation is simple and the defoaming effect is good.

Claims

1. A system for automatically adding a defoaming agent to a phosphate ester fire-resistant oil system, characterized in that: It comprises a defoaming agent adding device (1), a defoaming agent sampling device, a displacement testing device and a defoaming agent adding control system (12), wherein: The defoamer adding device (1) is placed in the oil tank (13) and fixed to the upper part of the oil return pipe (14) on the oil return side. The bottom of the defoamer adding device (1) is no more than 1 cm away from the oil flow position of the oil return pipe (14). A filter screen (15) is provided at the bottom outlet of the defoamer adding device (1). The first inlet of the defoamer adding device (1) is sealedly connected to the outlet of the defoamer injection device. The second inlet of the defoamer adding device (1) is sealedly connected to the outlet of the pressurizing device. The displacement test device floats on the liquid surface of the defoamer in the defoamer adding device (1). The defoamer addition control system (12) is connected to the defoamer injection device to control the opening and closing of the defoamer injection device and control the injection amount of the defoamer; The defoamer addition control system (12) is connected to the pressurizing device and is used to control the opening and closing of the pressurizing device and control the pressurizing device to apply pressure to the liquid surface of the defoamer. The pressurizing device pressurizes the defoamer liquid surface in the defoamer addition device (1) to 300 kPa±50 kPa and maintains a constant pressure during the defoamer addition process. The defoaming agent addition control system (12) is connected to the displacement testing device and is used to control the opening and closing of the displacement testing device; The filter screen (15) with a pore size of 0.5 μm to 3 μm is arranged at the bottom outlet of the defoamer adding device (1) to disperse the defoamer into particles and enter the oil system. The defoamer particles with a particle size of 0.5 μm to 3 μm will perform irregular Brownian motion in the oil system to form a stable colloid. The defoamer adding device (1) is a container surrounded by stainless steel plates arranged on all sides, a sealable cover on the top, and a stainless steel sintered filter screen with a pore size of 0.5 μm to 3 μm at the bottom. The first inlet and the second inlet of the defoamer adding device (1) are arranged on the sealable cover on the top of the defoamer adding device (1); The defoaming agent is a silicone defoaming agent, and the added amount of the silicone defoaming agent is 10 mg / kg based on the weight of the phosphate fire-resistant oil in the oil tank (13).

2. A system for automatically adding a defoaming agent to a phosphate ester fire-resistant oil system according to claim 1, characterized in that: The displacement test device and the defoamer adding control system (12) are connected wirelessly or by wire. In the case of a wired connection, the connection line passes through the third inlet of the defoamer adding device (1) and is sealed at the third inlet. The third inlet is arranged on a sealable cover at the top of the defoamer adding device (1).

3. A system for automatically adding a defoaming agent to a phosphate ester fire-resistant oil system according to claim 1, characterized in that: The defoaming agent injection device comprises a defoaming agent storage device (7), the outlet of the defoaming agent storage device (7) is connected to a first inlet of a defoaming agent adding device (1) through a pipeline, a micro liquid pump (6), a first electromagnetic valve (5) and a flow sensor (4) are arranged on the pipeline, and the micro liquid pump (6), the first electromagnetic valve (5) and the flow sensor (4) are all connected to a defoaming agent adding control system (12).

4. A system for automatically adding a defoaming agent to a phosphate ester fire-resistant oil system according to claim 1, characterized in that: The pressurizing device comprises a micro air pump (10), the outlet of the micro air pump (10) being connected to a second inlet of the defoaming agent adding device (1) via a pipeline, a second solenoid valve (9) and a pressure sensor (8) being provided on the pipeline, and the second solenoid valve (9) and the pressure sensor (8) being connected to a defoaming agent adding control system (12).

5. The system for automatically adding a defoaming agent to a phosphate ester fire-resistant oil system according to claim 1, characterized in that: The displacement testing device is a displacement sensor (3), and the displacement sensor (3) is connected to the defoaming agent addition control system (12).

6. A method for automatically adding a defoaming agent to a phosphate ester fire-resistant oil system, characterized in that: A system for automatically adding a defoaming agent to a phosphate fire-resistant oil system according to any one of claims 1 to 5 is used, wherein the specific steps of the method are as follows: S1, the defoamer addition control system (12) starts the defoamer injection device, the defoamer injection device adds a quantitative volume of defoamer into the defoamer addition device (1), and the defoamer addition control system (12) closes the defoamer injection device; S2, the defoamer addition control system (12) starts the pressurizing device, which pressurizes the defoamer liquid level in the defoamer addition device (1) to 300 kPa±50 kPa, and keeps the pressure constant during the defoamer addition process; S3, under the pressure of the pressurizing device, the defoamer in the defoamer adding device (1) is completely pressed into the oil tank (13) through the bottom filter (15), and when the displacement of the displacement testing device as the defoamer liquid level drops reaches the height of the defoamer in the defoamer adding device (1), the defoamer adding control system (12) controls the pressurizing device to release pressure and close; S4, the defoamer adding control system (12) determines whether it is necessary to add defoamer to the defoamer adding device (1) again according to the set number of times the defoamer adding device (1) releases the defoamer. If necessary, S1 to S4 are repeated. If not, the defoamer adding control system (12) is closed.

7. A method for automatically adding a defoaming agent to a phosphate ester fire-resistant oil system according to claim 6, characterized in that: The height of the defoamer in the defoamer adding device (1) is calculated based on the density of the defoamer, the bottom area of ​​the defoamer adding device (1) and the mass of the defoamer added to the defoamer adding device (1) each time. The specific calculation method is as follows: l = m / （ ρ · s ） in, l is the displacement distance of the displacement test device; ρ is the density of the defoamer; s is the bottom area of ​​the defoaming agent adding device (1); m The quality of the defoamer.

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