A heat exchanger automatic detection anti-scaling and descaling cleaning system and cleaning method thereof

Abstract

The present invention provides a heat exchanger automatic detection anti-scaling and descaling cleaning system and a cleaning method thereof. The heat exchanger automatic detection anti-scaling and descaling cleaning system comprises a heat exchanger, wherein a heat exchange tube is arranged inside the heat exchanger, and a water inlet pipe and a water outlet pipe are connected to the two ends of the heat exchange tube, respectively. In addition, the heat exchanger automatic detection anti-scaling and descaling cleaning system also comprises an anti-scaling mechanism, a descaling mechanism, a scale collecting mechanism and a tube wall thickness detection mechanism. The heat exchanger automatic detection anti-scaling and descaling cleaning system integrates automatic real-time detection, anti-scaling and descaling, and cleaning, has a high degree of automation, is easy to use, and has a good heat exchange effect. By sterilizing the external water and reducing the hardness, the intensity of scaling is essentially reduced to prevent scaling, and the anti-scaling and descaling effect is good. At the same time, the heat exchanger is descaled online without delaying the work of the heat exchanger. The heat exchange work efficiency is high, and the hot water exchange and cleaning water resources are recycled to reduce the waste of water resources.

Description

Technical Field

[0001] The invention relates to a circulating water descaling technology, and in particular to a heat exchanger automatic detection anti-scaling and descaling cleaning system and a cleaning method thereof. Background Art

[0002] Evaporator is a device that transfers part of the heat of hot fluid to cold fluid, also known as heat exchanger. Evaporator plays an important role in chemical, petroleum, power, food and many other industrial production. In chemical production, evaporator can be used as heater, cooler, condenser, evaporator and reboiler, etc., and is widely used. However, the circulating water in the evaporator water system is prone to retain sediment and form scale in the pipeline and other parts during operation. On the one hand, scaling will reduce the heat transfer wall area of ​​the pipeline, reduce the heat transfer, and cause fuel waste; on the other hand, the scale layer has a small thermal conductivity and has a significant heat insulation effect, which greatly increases the temperature of the scale part, causing local overheating of the pipeline, damage to the pipeline, and even cause overheating and bursting of the pipe; at the same time, the formation of scale will reduce the flow section of the water system, and even block the pipeline, which will have a serious impact on the circulation of the water system. In short, the formation of scale will greatly reduce the heat exchange performance of the evaporator, increase energy consumption, and shorten the life. Therefore, the anti-scaling and descaling of the evaporator has become a very important energy-saving topic. At present, the commonly used circulating water descaling and anti-scaling methods are: ion exchange method, chemical reagent method, chemical cleaning method, magnetic treatment method and electrochemical method, but these methods all have certain defects.

[0003] Chinese Patent No. 201620429575.X discloses an automatic descaling system for heat exchangers, which uses a combination of chemical and physical methods to descale the heat exchanger, and has a good descaling effect. However, the material of the heat exchanger plate is stainless steel or other metals, and the chemical reaction will produce a certain corrosion effect on the plate. The longer the time, the more serious the corrosion, and the greater the damage to the heat exchanger. Chinese Patent No. 201520818772.6 discloses an ultrasonic descaling device for a volumetric heat exchanger, which includes an external ultrasonic heat exchanger arranged on the heat exchanger shell, which is used to ultrasonically descale the shell and the heat exchange tube. Ultrasonic waves can indeed achieve the effect of anti-scaling and descaling, but in this invention, its external ultrasonic transducer is in a state of continuous excitation vibration, which is easy to cause mechanical damage to the equipment and will damage the life of the ultrasonic transducer, which is not conducive to long-term work. Summary of the invention

[0004] In view of the above problems, the present invention aims to provide an automatic detection, anti-scaling and descaling cleaning system for a heat exchanger which has high anti-scaling and descaling efficiency, is pollution-free to the environment and is highly safe.

[0005] To achieve the above-mentioned purpose, the present invention provides a heat exchanger automatic detection anti-scaling and descaling cleaning system, which includes a heat exchanger, wherein a heat exchange tube is arranged in the heat exchanger, and a water inlet pipe and a water outlet pipe are connected to the two ends of the heat exchange tube respectively. In addition, the heat exchanger automatic detection anti-scaling and descaling cleaning system also includes: an anti-scaling mechanism, which includes a water inlet tank, a water storage tank and a water production tank, a sterilization device is arranged in the water inlet tank, a spray head is arranged above the water storage tank, and a nanofiltration membrane is arranged in the water storage tank. The water inlet tank, the water storage tank and the heat exchanger are connected in sequence through pipelines to form an anti-scaling water circulation system, and the water production tank is connected to the water outlet pipe and the water inlet pipe through two or three-way regulating valves; a descaling mechanism, which includes a water inlet tank, a water storage tank and a water production tank, a sterilization device is arranged in the water inlet tank, a spray head is arranged above the water storage tank, and a nanofiltration membrane is arranged in the water storage tank. The water inlet tank, the water storage tank and the heat exchanger are connected in sequence through pipelines to form an anti-scaling water circulation system. The water production tank is connected to the water outlet pipe and the water inlet pipe through two or three-way regulating valves; a descaling mechanism, which includes The invention discloses an ultrasonic pipe descaling device, which comprises an ultrasonic power supply and a predetermined number of ultrasonic transducers connected to the ultrasonic power supply, wherein each of the ultrasonic transducers is arranged on the heat exchange tube and each pipe; a scale collecting mechanism, which comprises a connecting pipe, wherein one end of the connecting pipe passes through the water storage tank and is connected to a scale box, wherein the scale box is connected to a vacuum pump, and one end of the connecting pipe away from the scale box is connected to a rotating cleaning mechanism, wherein the rotating cleaning mechanism is connected to a motor; and a pipe wall thickness detecting mechanism, which comprises a main controller, a receiver and a pipe wall thickness measuring device connected to the receiver, wherein the main controller is connected to the receiver, the ultrasonic power supply, the three-way regulating valve and the motor.

[0006] Further preferably, a slide rail is provided on the heat exchange tube, a slider is slidably provided on the slide rail, and the tube wall thickness measuring device is provided on the slider.

[0007] Further preferably, a first liquid inlet pipe is provided on the water inlet tank, a second liquid inlet pipe is provided on the water storage tank, a water pump and a flow regulating electric valve are provided on the first liquid inlet pipe, the second liquid inlet pipe, the water inlet pipe and the water outlet pipe, the water pump and the flow regulating electric valve are connected to the receiver, two ends of the second liquid inlet pipe are respectively connected to the sprinkler head and the water inlet tank, and an impurity filtering device is provided in the first liquid inlet pipe.

[0008] Further preferably, a pressure sensor is disposed on the nanofiltration membrane, and a liquid level sensor is disposed below the nanofiltration membrane, and both the pressure sensor and the liquid level sensor are connected to the receiver.

[0009] Further preferably, a dirt filter is provided in the dirt storage box to prevent non-gas from entering the vacuum pump.

[0010] Further preferably, the water tank is of a cylindrical structure, and is further provided with an air inlet pipe, and an air inlet solenoid valve is provided on the air inlet pipe, and the air inlet pipe is provided at a height on the water tank higher than the height of the nanofiltration membrane.

[0011] Further preferably, the rotating cleaning mechanism includes a rotating fixed disk and a rotating cleaning brush, the rotating fixed disk is connected to a telescopic rod, the end of the telescopic rod away from the rotating fixed disk is connected to the upper end of the water tank, the rotating fixed disk is in the shape of a "flat spiral", the spacing between each "spiral" is adapted to the size of the spray head, and a spiral groove consistent with the extension direction of the rotating fixed disk is provided on the side of the rotating fixed disk away from the connecting tube, the rotating cleaning brush includes a trumpet-shaped brush handle, an end with a smaller diameter is connected to the connecting tube, and the corresponding other end is provided with soft bristles, the end of the rotating cleaning brush connected to the connecting tube is slidably arranged in the spiral groove via a slider, and the diameter of the end of the brush handle away from the connecting tube corresponds to the center distance of each "spiral".

[0012] Further preferably, a groove matching the spiral groove is provided on the upper end surface of the water storage tank, and the connecting pipe passes through the groove and is connected to the brush handle.

[0013] Further preferably, a movable soft plate is movably provided in the groove, an opening is provided on the movable soft plate, a diameter of the opening is matched with an outer diameter of the connecting tube, and the connecting tube passes through the opening and is connected to the brush handle.

[0014] The present invention also provides a cleaning method of a heat exchanger automatic detection anti-scaling and descaling cleaning system, which is implemented by the above-mentioned heat exchanger automatic detection anti-scaling and descaling cleaning system, and includes the following steps:

[0015] 1) Preparation before work: install the ultrasonic transducer on the pipeline connecting the anti-scaling water circulation and the water production circulation in a manner of surrounding the outer wall of the pipeline, and connect it to the ultrasonic power supply, and proceed to step 2);

[0016] 2) Anti-scaling start: turn on the main controller, the heat exchanger, the pressure sensor, the first liquid inlet pipe, the second liquid inlet pipe, the water inlet pipe and the water pump and the flow regulating electric valve on the water outlet pipe, and the channel between the heat exchange pipe and the water inlet tank in the three-way regulating valve is opened. After water enters the water inlet tank from the first liquid inlet pipe for sterilization, it enters through the spray head and is sprayed onto the nanofiltration membrane. The nanofiltration membrane intercepts calcium and magnesium ions in the water, reduces the hardness of the water, and then enters the heat exchanger for heat exchange, and then returns to the water inlet tank to form an anti-scaling water cycle;

[0017] 3) Liquid level monitoring: The liquid level sensor monitors the liquid level in the water tank in real time, and compares the liquid level detection value L with the set liquid level setting value L1. If L≤L1, repeat step 2); if L>L1, proceed to step 3);

[0018] 4) Water inlet stop: The water pump and flow regulating electric valve on the first water inlet pipe are closed, and step 4) is entered;

[0019] 5) Cleaning of impurity filtration device: Remove the impurity filtration device and clean it;

[0020] 6) Nanofiltration membrane pressure detection: The pressure sensor monitors the pressure on the nanofiltration membrane in real time, and compares the pressure detection value P with the pressure set values P1 and P2. If P1 ≤ P ≤ P2, step 6) is repeated. If P < P1, the power of the water pump in the pipeline between the water inlet tank and the water storage tank is increased, and the flow regulating valve on the same pipeline adjusts the flow rate to increase. If P2 < P, the power of the water pump in the pipeline between the water inlet tank and the water storage tank is decreased, and the flow regulating valve on the same pipeline adjusts the flow rate to decrease;

[0021] 7) Pipe wall thickness detection: Turn on the pipe wall thickness detection mechanism, monitor the pipe wall thickness of each pipeline and the heat exchange pipe in real time, and compare the pipe wall thickness detection value X with the wall thickness set value X1. If X < X1, step 7) is repeated; if X ≥ X1, step 8) is entered;

[0022] 8) Scale removal start: The ultrasonic power supply is turned on to perform ultrasonic cleaning on the scale in each pipeline and the heat exchange pipe, and at the same time step 7) is performed. If X ≥ X1, step 8) is repeated. If X < X1, step 9) is entered;

[0023] 9) Scale removal stop: The ultrasonic power supply is turned off to stop scale removal, and step 10) is entered, and at the same time step 7) is performed;

[0024] 10) Scale collection start: The intake solenoid valve on the intake pipe is turned on, the pressure sensor is turned off, the channels from the outlet pipe to the product water tank and from the product water tank to the water inlet pipe among the two three-way regulating valves are opened. After the liquid level in the water storage tank is below the nanofiltration membrane, the scale collection mechanism is turned on. The telescopic rod is adjusted so that the soft hair contacts the nanofiltration membrane, the motor drives the rotary cleaning brush to rotate, and the nanofiltration membrane is cleaned. The vacuum pump creates a low pressure in the scale accumulation tank, so that the scale and other impurities on the nanofiltration membrane enter the scale accumulation tank through the connecting pipe, and the nanofiltration membrane is cleaned. After a certain period of time, step 11) is entered;

[0025] 11) Scale collection end: The motor and the vacuum pump are turned off, and the telescopic rod is adjusted to drive the rotary cleaning mechanism to reach the highest point of the water storage tank, and step 12) is entered;

[0026] 12) Anti-scaling water circulation is turned on: the channel from the water outlet pipe to the water production tank in the two three-way regulating valves is closed, and the channel from the water outlet pipe to the water inlet tank in the three-way regulating valve is opened. After a certain period of time, the channel from the water production tank to the water inlet tank is closed, and the channel from the water storage tank to the water inlet pipe is opened, and the process goes to step 6).

[0027] The beneficial effects of the present invention are as follows: the heat exchanger automatic detection, anti-scaling, descaling and cleaning system provided by the present invention integrates automatic real-time detection, anti-scaling, descaling and cleaning, has a high degree of automation, is easy to use, has a wide range of applications, and is accurate and reliable;

[0028] The slider drives the tube wall thickness measuring device to move along the heat exchange tube, so as to monitor the tube wall thickness at different positions of the heat exchange tube, thereby avoiding the influence of scaling on the heat exchange effect of the heat exchanger to the greatest extent, achieving good heat exchange effect, saving energy and reducing resource waste;

[0029] By sterilizing the external water and reducing the hardness, the scaling force is essentially reduced, scaling is prevented, the descaling interval is extended, and the descaling intensity is reduced. The problem of mechanical damage to the pipeline caused by continuous vibration descaling in ultrasonic descaling is solved, and the damage to the life of the heat exchanger by ultrasonic descaling is reduced, and the anti-scaling and descaling effect is good;

[0030] Anti-scaling water circulation and water production circulation are set up. When the scale collection and cleaning is started, the heat exchange of the heat exchanger uses the water production circulation, so that the heat exchange of the heat exchanger is uninterrupted, and the online descaling of the heat exchanger is realized without delaying the work of the heat exchanger. The heat exchange efficiency is high, and at the same time, the hot water and cleaning water resources are recycled to reduce the waste of water resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of a heat exchanger automatic detection, anti-scaling, descaling and cleaning system provided by a first embodiment of the present invention;

[0032] Figure 2 1 is a schematic diagram of the structure of the heat exchange tube portion of the heat exchanger automatic detection anti-scaling and descaling cleaning system provided by the first embodiment of the present invention;

[0033] Figure 3 2 is a schematic diagram of the structure of a rotary cleaning mechanism of a heat exchanger automatic detection anti-scaling and descaling cleaning system provided in the first embodiment of the present invention;

[0034] Figure 4 It is a partial structural schematic diagram of a water storage tank in the heat exchanger automatic detection anti-scaling and descaling cleaning system provided by the first embodiment of the present invention;

[0035] Figure 5 It is a flow chart of a cleaning method of a heat exchanger automatic detection anti-scaling and descaling cleaning system provided in the first embodiment of the present invention. DETAILED DESCRIPTION

[0036] The embodiments described below are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Example 1

[0038] See also Figure 1 The present embodiment provides a heat exchanger automatic detection anti-scaling, descaling and cleaning system, which includes a heat exchanger 1, wherein a heat exchange tube 11 is arranged in the heat exchanger 1, and an inlet pipe 12 and an outlet pipe 13 are respectively connected to the two ends of the heat exchange tube 11. The heat exchanger automatic detection anti-scaling, descaling and cleaning system also includes an anti-scaling mechanism 2, a descaling mechanism 3, a scale collecting mechanism 4 and a tube wall thickness detection mechanism.

[0039] The anti-scaling mechanism 2 includes a water inlet tank 21, a water storage tank 22 and a water production tank 23. The water storage tank 22 is a cylindrical structure. An air inlet pipe 221 is also provided on the water storage tank 22. An air inlet solenoid valve d is provided on the air inlet pipe 221. The water inlet tank 21 is provided with a first liquid inlet pipe 211, and the first liquid inlet pipe 211 is provided with an impurity filtering device 212. The impurity filtering device 212 is detachably connected to the first liquid inlet pipe 211, and is used to filter impurities such as mud, dead grass, etc. in the exogenous water. The water inlet tank 21 is provided with a sterilizing device 213, and is used to sterilize the exogenous water entering the water inlet tank 21. The sterilizing device 213 can be a sterilizing bag containing sterilizing drugs. The water storage tank 22 is provided with a nanofiltration membrane 223, and the nanofiltration membrane 223 is connected to the side wall of the water storage tank 22, and is used to separate calcium and magnesium ions in the exogenous water, reduce the hardness of the exogenous water, and make the pipeline less prone to scaling. A pressure sensor 224 is provided above the nanofiltration membrane 223, and the detection point of the pressure sensor 224 is at the position of the nanofiltration membrane 223. The operating pressure of the nanofiltration membrane 223 is generally 3.5 to 30 bar. The pressure sensor 224 is used to detect the nanofiltration membrane 223. The pressure to be borne ensures that the pressure borne by the nanofiltration membrane 223 meets its operating pressure. A liquid level sensor 227 is arranged below the nanofiltration membrane to monitor the liquid level in the water storage tank 22. A spray head 225 is arranged above the water storage tank 22. The spray head 225 is connected to a second liquid inlet pipe 226 arranged outside the water storage tank 22. A three-way regulating valve e, e, and f are respectively arranged on the water inlet pipe 12 and the water outlet pipe 13. f, the end of the second liquid inlet pipe 226 away from the water storage tank 22 is connected to the water inlet tank 21, the water storage tank 22 and the water production tank 23 are both connected to the water inlet pipe 12 through the three-way regulating valve e on the water inlet pipe 12, the water inlet tank 21 and the water production tank 23 are both connected to the water outlet pipe 13 through the three-way regulating valve f of the water outlet pipe 13, the water inlet tank 21, the water storage tank 22 and the heat exchanger 1 constitute an anti-scaling water circulation system, the water production tank 23 and the heat exchanger 1 constitute a water production circulation system, the first liquid inlet pipe 211, the second liquid inlet pipe 226, the water inlet pipe 12 and the water outlet pipe 13 are all provided with a flow regulating electric valve a and a water pump b, the water pump b and the flow regulating electric valve a on the first liquid inlet pipe 211 are arranged behind the water circulation direction of the impurity filtering device 212.

[0040] See also Figure 1 and Figure 2The descaling mechanism 3 includes an ultrasonic pipe descaling device, which includes an ultrasonic power supply (not shown) and a predetermined number of ultrasonic transducers c connected to the ultrasonic power supply. The ultrasonic transducer c is arranged on the heat exchange tube 11 in a welding manner. The ultrasonic transducer c is arranged on the first liquid inlet pipe 211, the second liquid inlet pipe 226, the water inlet pipe 12 and the water outlet pipe 13 in a manner of embracing the outer wall of the pipe. A slide rail 111 is arranged on the heat exchange tube 11, and the slide rail 111 extends in the same direction as the heat exchange tube 11. A slider 112 is arranged on the slide rail, and a driving motor is arranged in the slider 112 for driving the slider 112.

[0041] See also Figure 1 , Figure 3 and Figure 4The scale collecting mechanism 4 includes a connecting pipe 41, one end of which passes through the water storage tank 22 and is connected to a scale box 42. The scale box 42 is connected to a vacuum pump 43. A scale filter 421 is provided between the scale box 42 and the vacuum pump 43 to prevent non-gas from entering the vacuum pump 43. One end of the connecting pipe 41 away from the scale box 42 is connected to a rotating cleaning mechanism 44, and the rotating cleaning mechanism 44 is connected to a motor (not shown). The rotating cleaning mechanism 44 includes a rotating fixed disk 441 and a rotating cleaning brush 442. The rotating fixed disk 441 is connected to a telescopic rod 443. The end of the telescopic rod 443 away from the rotating fixed disk 441 is connected to the upper end of the water tank 22. The rotating fixed disk 441 is in the shape of a "flat spiral". The spacing between each "flat spiral" is adapted to the size of the spray head 225. When the spray head 225 is working, the telescopic rod 443 drives the rotating cleaning mechanism 44 to the uppermost end of the water tank 22. The spray head 225 extends from the "flat spiral" of the fixed rotating disk, so that the rotating cleaning mechanism 44 does not affect the spray head 225 to evenly spray water onto the nanofiltration membrane 223, thereby ensuring that the pressure on the nanofiltration membrane 223 is uniform. The rotating fixed disk 441 is provided with a spiral groove 444 which is consistent with the extension direction of the "plane spiral". The rotating cleaning brush 442 includes a trumpet-shaped brush handle, the end with a smaller diameter is connected to the connecting tube 41, and the other corresponding end is provided with soft bristles. The end of the rotating cleaning brush 442 connected to the connecting tube 41 is slidably arranged in the spiral groove 444 via a slider, and the diameter of the end of the rotating cleaning brush 442 away from the connecting tube corresponds to the center distance of each "plane spiral".The top surface of the water storage tank 22 is provided with a groove 445 corresponding to the spiral groove 444, the outer diameter of the groove 445 extends to the outside of the water storage tank 22, a movable soft plate 446 is movably provided in the groove 445, and an opening 447 adapted to the outer diameter of the connecting pipe 41 is provided on the movable soft plate 446, the connecting pipe 41 passes through the opening 447 and is connected to the brush handle, when the rotary cleaning mechanism 44 is working, the motor drives the rotary cleaning brush 442 The scale and other impurities on the nanofiltration membrane 223 are cleaned by rotation. The vacuum pump 43 forms a low pressure in the scale box 42, and the scale and other impurities on the nanofiltration membrane 223 are sucked into the scale box 42 through the connecting pipe 41. When the rotating cleaning brush 442 moves from the inside to the outside along the spiral groove 444 to clean the nanofiltration membrane 223, the connecting pipe 41 cooperates with the rotating cleaning brush 442 to move in the slot 445. The movable soft plate 446 moves out of the slot 445 as the connecting pipe 41 moves. When the rotating cleaning brush 442 returns to the origin, the movable soft plate 446 also returns to its original position, so that the water storage tank 22 returns to a sealed state.

[0042] A pipe wall thickness detection mechanism includes a main controller (not shown), a receiver and a pipe wall thickness measuring device 51 connected to the receiver. The pipe wall thickness measuring device 51 is arranged on the slider 112. The pipe wall thickness measuring device can be a pipe wall thickness gauge. The main controller is connected to the receiver, the ultrasonic power supply, the vacuum pump 43 and the motor. The receiver is connected to the pressure sensor 224, the three-way regulating electric valves e and f, the pipe wall thickness measuring device 51, the ultrasonic transducer c, the water pump b and each of the flow regulating electric valves a. The receiver receives the detection signal of the pipe wall thickness measuring device 51, and the receiver transmits the received detection signal to the main controller. After being processed by the main controller, the pipe wall thickness is obtained, and the pipe wall thickness is monitored, so as to determine whether the pipe wall is scaled.

[0043] See also Figure 5 The present invention also provides a cleaning method of a heat exchanger automatic detection anti-scaling and descaling cleaning system, which is implemented using the above-mentioned heat exchanger automatic detection anti-scaling and descaling cleaning system, and includes the following steps:

[0044] 1) Preparation before work: install the ultrasonic transducer c on the pipeline connecting the anti-scaling water circulation and the water production circulation in a manner of surrounding the outer wall of the pipeline, and connect it to the ultrasonic power supply to proceed to step 2);

[0045] 2) Anti-scaling start: Turn on the main controller, the heat exchanger 11 and the pressure sensor 224 are turned on, the water pumps b and the flow regulating electric valves a on the first liquid inlet pipe 211, the second liquid inlet pipe 226, the water inlet pipe 12 and the water outlet pipe 13 are turned on, and the channel between the heat exchange pipe 11 and the water inlet tank 21 in the three-way regulating valve e on the water inlet pipe 12 is opened. After the external source water enters the water inlet tank 21 from the first liquid inlet pipe 211 for sterilization, it enters through the spray head 225 and is sprayed onto the nanofiltration membrane 223. The nanofiltration membrane 223 intercepts calcium and magnesium ions in the water, reduces the hardness of the water, and then enters the heat exchanger 1 for heat exchange work, and then returns to the water inlet tank 21 to form an anti-scaling water cycle;

[0046] 3) Liquid level monitoring: The liquid level sensor 227 monitors the liquid level in the water storage tank 22 in real time, compares the liquid level detection value L with the set liquid level set value L1. If L ≤ L1, repeat step 2). If L > L1, enter step 3);

[0047] 4) Water inlet stop: The water pump b and the flow regulating electric valve a on the first water inlet pipe 12 are closed, and enter step 4);

[0048] 5) Cleaning of the impurity filtering device 212: Remove the impurity filtering device 212 and clean it;

[0049] 6) Pressure detection of the nanofiltration membrane 223: The pressure sensor 224 monitors the pressure received by the nanofiltration membrane 223 in real time, and compares the pressure detection value P with the pressure set values P1 and P2. If P1 ≤ P ≤ P2, repeat step 6). If P < P1, the power of the water pump b on the pipeline between the water inlet tank 21 and the water storage tank 22 increases, and the flow regulating electric valve a on the same pipeline adjusts the flow rate to increase. If P2 < P, the power of the water pump b on the pipeline between the water inlet tank 21 and the water storage tank 22 decreases, and the flow regulating electric valve a on the same pipeline adjusts the flow rate to decrease;

[0050] 7) Online cleaning preparation:

[0051] 8) Pipe wall thickness detection: Turn on the pipe wall thickness detection mechanism, monitor the pipe wall thickness of each pipeline and the heat exchange pipe 11 in real time, compare the pipe wall thickness detection value X with the wall thickness set value X1. If X < X1, repeat step 7); If X ≥ X1, enter step 8);

[0052] 9) Anti-scaling start: Turn on the ultrasonic power supply, perform ultrasonic cleaning on the scale in each pipeline and the heat exchange pipe 11, and at the same time perform step 7). If X ≥ X1, repeat step 8). If X < X1, enter step 9);

[0053] 10) Descaling stops: the ultrasonic power is turned off, descaling stops, and the process goes to step 10), and step 7) is performed at the same time;

[0054] 11) Scale collection and cleaning is turned on: the air intake solenoid valve d on the air intake pipe 221 is turned on, the pressure sensor 224 is turned off, the channels between the outlet pipe 13 and the water production tank 23 and between the water production tank 23 and the water inlet pipe 12 in the two three-way regulating valves e and f are turned on, and when the liquid level in the water storage tank 22 is below the nanofiltration membrane 223, the scale collection mechanism 4 is turned on, the telescopic rod 443 is adjusted to the point where the soft hair contacts the nanofiltration membrane 223, the motor drives the rotating cleaning brush 442 to rotate, and the nanofiltration membrane 223 is cleaned. The vacuum pump 43 forms a low pressure in the scale box 42, so that the scale and other impurities on the nanofiltration membrane 223 enter the scale box 42 from the connecting pipe 41, and the nanofiltration membrane 223 is cleaned. After a certain period of time, the process proceeds to step 11);

[0055] 12) Scale collection and cleaning is finished: turn off the motor and the vacuum pump 43, adjust the telescopic rod 443 to drive the rotating cleaning mechanism 44 to reach the highest point of the water storage tank 22, and proceed to step 12);

[0056] 13) Anti-scaling water circulation is turned on: the channel from the outlet pipe 13 to the water production tank 23 in the two three-way regulating valves is closed, and the channel from the outlet pipe 13 to the water inlet tank 21 in the three-way regulating valve is opened. After a certain period of time, the channel from the water production tank 23 to the water inlet tank 21 is closed, and the channel from the water storage tank 22 to the water inlet pipe 12 is opened, and the process goes to step 6).

[0057] The heat exchanger automatic detection, anti-scaling, descaling and cleaning system provided in this embodiment integrates automatic real-time detection, anti-scaling, descaling and cleaning, with a high degree of automation, easy use, wide application range, accuracy and reliability; the slider 112 drives the tube wall thickness measuring device 51 to move along the heat exchange tube 11 to monitor the tube wall thickness at different positions of the heat exchange tube 11, thereby avoiding the influence of scaling on the heat exchange effect of the heat exchanger 1 to the greatest extent, achieving good heat exchange effect, saving energy and reducing resource waste; by sterilizing the external water and reducing the hardness, the scaling force is essentially reduced, scaling is prevented, the descaling interval time is extended and the descaling intensity is reduced, the problem of mechanical damage to the pipeline caused by continuous vibration descaling in ultrasonic descaling is solved, the damage to the life of the heat exchanger caused by ultrasonic descaling is reduced, and the anti-scaling and descaling effect is good; an anti-scaling water cycle and a water production cycle are set, and when the scale collection and cleaning is started, the heat exchange work of the heat exchanger uses the water production cycle, so that the heat exchange work of the heat exchanger is uninterrupted, and the online descaling of the heat exchanger is realized, the work of the heat exchanger is not delayed, and the heat exchange work efficiency is high.

[0058] The above disclosures are only several preferred embodiments of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention are still within the scope covered by the present invention.

Claims

1. A heat exchanger automatic detection anti-scaling and descaling cleaning system, comprising a heat exchanger, wherein a heat exchange tube is arranged in the heat exchanger, and a water inlet pipe and a water outlet pipe are connected to the two ends of the heat exchange tube, respectively, characterized in that: The heat exchanger automatic detection anti-scaling and descaling cleaning system also includes: An anti-scaling mechanism, comprising a water inlet tank, a water storage tank and a water production tank, wherein a sterilizing device is arranged in the water inlet tank, a spray head is arranged above the water storage tank, a nanofiltration membrane is arranged in the water storage tank, the water inlet tank, the water storage tank and the heat exchanger are connected in sequence through pipelines to form an anti-scaling water circulation system, the water production tank is connected to the water outlet pipe and the water inlet pipe through two or three-way regulating valves, and the water production tank and the heat exchanger form a water production circulation; A descaling mechanism, comprising an ultrasonic pipeline descaling device, the ultrasonic pipeline descaling device comprising an ultrasonic power supply and a predetermined number of ultrasonic transducers connected to the ultrasonic power supply, each of the ultrasonic transducers being arranged on the heat exchange tube and each pipeline; A scale collecting mechanism, comprising a connecting pipe, one end of which passes through the water storage tank and is connected to a scale box, the scale box is connected to a vacuum pump, one end of the connecting pipe away from the scale box is connected to a rotating cleaning mechanism, the rotating cleaning mechanism is connected to a motor, and a scale filter is arranged in the scale box to prevent non-gas from entering the vacuum pump; A pipe wall thickness detection mechanism comprises a main controller, a receiver and a pipe wall thickness measuring device connected to the receiver, wherein the main controller is connected to the receiver, the ultrasonic power supply, the three-way regulating valve and the motor, wherein a slide rail is arranged on the heat exchange tube, a slider is slidably arranged on the slide rail, and the pipe wall thickness measuring device is arranged on the slider.

2. The heat exchanger automatic detection anti-scaling and descaling cleaning system according to claim 1, characterized in that: A first liquid inlet pipe is arranged on the water inlet tank, a second liquid inlet pipe is arranged on the water storage tank, a water pump and a flow regulating electric valve are arranged on the first liquid inlet pipe, the second liquid inlet pipe, the water inlet pipe and the water outlet pipe, the water pump and the flow regulating electric valve are connected to the receiver, two ends of the second liquid inlet pipe are respectively connected to the sprinkler head and the water inlet tank, and an impurity filtering device is arranged in the first liquid inlet pipe.

3. The heat exchanger automatic detection anti-scaling and descaling cleaning system according to claim 2, characterized in that: A pressure sensor is arranged on the nanofiltration membrane, and a liquid level sensor is arranged below the nanofiltration membrane. Both the pressure sensor and the liquid level sensor are connected to the receiver.

4. The heat exchanger automatic detection anti-scaling and descaling cleaning system according to claim 3 is characterized in that: The water storage tank is of a cylindrical structure, and is also provided with an air intake pipe, on which is provided an air intake solenoid valve. The air intake pipe is provided at a height on the water storage tank that is higher than the height of the nanofiltration membrane.

5. The heat exchanger automatic detection anti-scaling and descaling cleaning system according to claim 4, characterized in that: The rotary cleaning mechanism includes a rotary fixed disk and a rotary cleaning brush. The rotary fixed disk is connected to a telescopic rod, and one end of the telescopic rod away from the rotary fixed disk is connected to the upper end surface of the water storage tank. The rotary fixed disk is in the shape of a "plane spiral", and the spacing of each "plane spiral" is adapted to the size of the spray head. A spiral groove consistent with the extending direction of the rotary fixed disk is arranged on one side of the rotary fixed disk away from the connecting pipe. The rotary cleaning brush includes a horn-shaped brush handle, the smaller-diameter end of which is connected to the connecting pipe, and soft hairs are arranged at the corresponding other end. One end of the rotary cleaning brush connected to the connecting pipe is slidably arranged in the spiral groove through a slider, and the diameter of the end of the brush handle away from the connecting pipe corresponds to the center distance of each "plane spiral".

6. The heat exchanger automatic detection anti-scaling and descaling cleaning system according to claim 5, characterized in that: A slot matching the spiral groove is arranged on the upper end surface of the water storage tank, and the connecting pipe passes through the slot and is connected to the brush handle.

7. The heat exchanger automatic detection anti-scaling and descaling cleaning system according to claim 6, characterized in that: A movable soft plate is movably arranged in the slot, and an opening is formed on the movable soft plate. The diameter of the opening is adapted to the outer diameter of the connecting pipe, and the connecting pipe penetrates through the opening and is connected to the brush handle.

8. A cleaning method for a heat exchanger automatic detection anti-scaling and descaling cleaning system, characterized in that: It is realized by the heat exchanger automatic detection, scale prevention and cleaning system according to any one of claims 5 to 7, and includes the following steps: 1) Preparation before work: Install the ultrasonic transducer on the pipeline connecting the scale prevention water circulation and the product water circulation in a way of surrounding the outer wall of the pipeline, and connect it to the ultrasonic power supply, then enter step 2); 2) Scale prevention start: Turn on the main controller, turn on the heat exchanger and the pressure sensor, turn on the water pumps and the flow regulating electric valves on the first liquid inlet pipe, the second liquid inlet pipe, the water inlet pipe and the water outlet pipe, open the channel between the heat exchange pipe and the water inlet tank in the three-way regulating valve. After water enters the water inlet tank from the first liquid inlet pipe for sterilization, it enters the spray head and is sprayed onto the nanofiltration membrane. The nanofiltration membrane intercepts calcium and magnesium ions in the water, reduces the hardness of the water and then enters the heat exchanger for heat exchange work, and then returns to the water inlet tank to form a scale prevention water circulation; 3) Liquid level monitoring: The liquid level sensor monitors the liquid level in the water storage tank in real time, compares the liquid level detection value L with the set liquid level set value L1. If L≤L1, then repeat step 3). If L>L1, then enter step 4); 4) Water inlet stop: Close the water pump and the flow regulating electric valve on the water inlet pipe, and enter step 5); 5) Cleaning of the impurity filtering device: Remove the impurity filtering device and clean it; 6) Pressure detection of the nanofiltration membrane: The pressure sensor monitors the pressure received by the nanofiltration membrane in real time, and compares the pressure detection value P with the pressure set values P1 and P2 (P1<P2). If P1≤P≤P2, then repeat step 6). If P<P1, then increase the power of the water pump on the pipeline between the water inlet tank and the water storage tank, and adjust the flow rate to become larger by the flow regulating valve on the same pipeline. If P2<P, then reduce the power of the water pump on the pipeline between the water inlet tank and the water storage tank, and adjust the flow rate to become smaller by the flow regulating valve on the same pipeline; 7) Wall thickness detection: Activate the wall thickness detection mechanism to continuously monitor the wall thickness of each pipeline and the heat exchange tubes. Compare the detected wall thickness value X with the set wall thickness value X1. If X < X1, repeat step 7); if X ≥ X1, proceed to step 8). 8) Scaling removal start: Turn on the ultrasonic power supply to perform ultrasonic cleaning on the scale in each pipeline and the heat exchange tubes. At the same time, perform step 7). If X ≥ X1, repeat step 8); if X < X1, proceed to step 9). 9) Scaling removal stop: Turn off the ultrasonic power supply to stop scaling removal, and proceed to step 10). At the same time, perform step 7). 10) Scaling collection start: Open the intake solenoid valve on the intake pipe, close the pressure sensor, and open the channels between the outlet pipe and the production water tank and between the production water tank and the inlet pipe among the two three-way regulating valves. After the liquid level in the storage tank is below the nanofiltration membrane, activate the scaling collection mechanism. Adjust the telescopic rod so that the soft brush contacts the nanofiltration membrane, and drive the rotary cleaning brush to rotate with the motor to clean the nanofiltration membrane. The vacuum pump creates a low pressure in the scale collection tank, causing the scale and other impurities on the nanofiltration membrane to enter the scale collection tank through the connecting pipe to clean the nanofiltration membrane. After a certain period of time, proceed to step 11). 11) Scaling collection end: Turn off the motor and the vacuum pump, and adjust the telescopic rod to drive the rotary cleaning mechanism to reach the highest point of the storage tank, then proceed to step 12). 12) Anti-scaling water circulation start: Close the channel between the outlet pipe and the production water tank among the two three-way regulating valves, and open the channel between the outlet pipe and the inlet water tank. After a certain period of time, close the channel between the production water tank and the inlet water tank, and open the channel between the storage tank and the inlet pipe, then proceed to step 6).

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