KR20030009698A - apparatus for removing scale using ultrasonic wave and method for removing thereof - Google Patents

Abstract

PURPOSE: An apparatus for removing scale using ultrasonic waves and removing method of the same are provided to reduce man-power and time needed for removing scale. CONSTITUTION: An apparatus comprises an input power supply part(10) receiving direct current power for driving each part of a circuit; a constant voltage circuit part(11) making voltage impressed by the input power supply part constant; a micro controller part(12) receiving input power from the constant voltage circuit part to constantly and repeatedly output digital signal square waves; an output terminal part(17) converting square wave pulse generated by the micro controller part into sine wave and controlling power discharged directly from a power supply device to discharge output higher than input value; a display part(14) displaying frequency and working condition to allow to select frequency output through the micro controller part; and a magnetism generation and output part(18) comprising a pipe with a coil wounded thereon to output ultrasonic waves for removing scale and preventing the scale from attaching again by exerting strong force on ion particles or water molecules in water flowing in a pipe by digital signal output by the micro controller part.

Description

Apparatus for removing scale using ultrasonic wave and method for removing

The present invention relates to a scale removing device and a method for removing the same, and more particularly, to a scale removing device for removing a scale formed in a tube such as a heat exchanger using ultrasonic waves, and a method for removing the scale.

Ultrasound has been used in human life since the 1920s. Although initially developed for military purposes, it has been used in industry since the late 1940s, and has since been widely applied to various fields such as medicine.

On the other hand, the ultrasonic wave has an impact force, and has been widely used in a washing apparatus for removing a substance attached to a solid surface. In the 1970s, as ultrasonic cleaners, mainly magnets, were imported and sold, interest in ultrasonics became higher. These ultrasonic cleaners were initially applied to the descaling formed in the pipe, and the system was developed mainly for the purpose of preventing the scale of the building, but the performance was not as expected.

The scale is a solidified substance formed on the heat exchange tube tube wall due to the solid deposits of ozone oxygen, heavy metal ions and impurities in the water, depending on the boiler water used in the heat exchange tube and tube wall of industrial and heating boilers. Means.

U. S. Patent No. 5,074, 998 and Korean Patent No. 98-18625 also disclose an apparatus for removing scale generated on the exchange tube tube wall. This scale not only reduces the diameter inside the pipe, but also causes the thermal efficiency to decrease by reducing the thermal conductivity. For example, if the scale thickness is 0.5mm, the fuel loss rate increases by 0.2%, and when the scale thickness is 1mm, the fuel loss rate reaches 2.3%. As such, since the heat transfer is interrupted when the scale is attached, the amount of heat transferred to the pipe is reduced. Therefore, in order to maintain the same amount of heat generation, more heat must be applied, which can lead to an increase in energy consumption as well as overheating. In order to solve such a conventional problem, a cleansing agent and a chemical cleansing agent were also used to remove the scale, but this caused a problem in that manpower and time were wasted and water quality was contaminated due to interruption of operation.

Therefore, in order to solve the above problems such as water pollution, recently, in this field, a PWM driving method using a magnetostrictive oscillator, which is one of the non-chemical scale processing methods, has been introduced, but it is commercialized due to the problems of noise pollution and high cost. I am having a hard time.

It is therefore an object of the present invention to provide an improved scale removing apparatus and a method for removing the same, which can solve the above-mentioned conventional objects.

It is another object of the present invention to provide an improved scale removing apparatus and a method for removing the same, which are not concerned about waste of manpower and time.

Another object of the present invention is to provide an improved scale removing apparatus and a method for removing the same, which can solve the water pollution problem.

Another object of the present invention is to provide an improved scale removing apparatus and a method for removing the same, which can solve the noise problem.

Another object of the present invention is to provide an improved scale removing apparatus and its removal method which can be distributed not only to the industry but also to general households at a much more economical price than commercial products.

In order to achieve the above objects, the present invention provides an input power supply unit for inputting a DC power source for driving each part of the circuit; A constant voltage circuit unit for causing a constant voltage to be applied from the input power supply unit; A micro controller unit receiving input power from the constant voltage circuit unit to continuously output a digital signal square wave continuously; An output terminal unit for outputting an output value higher than an input by controlling a supply power directly coming from a power supply device by changing a square wave pulse generated by the microcontroller into a sine wave waveform; A display unit for displaying a frequency display and an operating state to select a frequency value output through the microcontroller unit; And an ultrasonic wave to remove scale and prevent adhesion again by applying a powerful force to the ion particles or water molecules in the water flowing in the pipe tube by the digital signal output from the microcontroller unit. Provided is a descaling device comprising a magnetic field generating output.

In addition, in order to achieve the above object, the present invention comprises the steps of generating an ultrasonic wave by a digital signal using a micro-controller and firing it on the boiler tube is generated scale; Contracting and expanding due to negative pressure in the internal water by the emitted ultrasonic waves, causing waves to propagate in the water to generate and extinguish tens of millions of fine air bubbles; Providing a scale removing method comprising the step of separating and removing the scale generated on the surface of the boiler tube by the strong energy generated during the bursting of the air bubbles and preventing the new scale from adhering to the surface. do.

1 is a principle configuration diagram for explaining the principle of descaling using ultrasonic waves according to an embodiment of the present invention.

2 and 3 are graphs showing the relationship between cavitation, pressure, and cavitation sound intensity and frequency, respectively.

4 is a schematic system configuration diagram of a scale removing apparatus according to an embodiment of the present invention.

FIG. 5 is a circuit diagram of FIG. 4.

6 is a flowchart of a frequency conversion control circuit for obtaining a digital waveform.

7 is a flowchart related to a timer interrupt.

8 is a flowchart related to timer 0.

9 is a flowchart related to timer 1. FIG.

<Brief Description of Drawings>

10: input power supply unit 11: constant voltage circuit unit

12: microcontroller portion 13: switching circuit portion

14: display unit 15: RL series circuit unit

16: mixer section 17: output terminal section (oscillation drive section)

18: magnetic field generating section

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a principle configuration diagram for explaining the principle of descaling using ultrasonic waves applied to an embodiment of the present invention.

When ultrasonic waves are fired into the boiler tube, the contraction and expansion caused by negative pressure alternately occur in the water, causing waves to propagate in the water, generating and destroying tens of millions of minute air bubbles. This phenomenon, in which fine air bubbles are repeatedly generated and dissipated, is called a cavitation phenomenon. This cavitation phenomenon generates strong energy when an air bubble bursts, separating the scale generated on the surface of the boiler tube and attaching a new scale to the surface. To prevent. That is, the vibration 2 of the bubble is generated by the cavitation 1 phenomenon, which causes the micro vortices 3 to be generated. This micro vortex 3 causes the water present in the boiler tube to be stirred 4. On the other hand, the cavitation (1) phenomenon raises the pressure of the bubbles (9), thereby raising the temperature of the bubbles (10), thereby causing the bubbles to break (6). Disruption (7) occurs due to the broken bubbles, which causes the water particles to be crushed (8). In addition, the micro-thermal action 11 is caused by the temperature rise 10 of the bubble, and the micro-thermal action 11 also pulverizes the water particles. The dispersing action 7 removes the deposit in the boiler tube 12 and thus removes the scale so that the scale is removed 5. The scale in the boiler tube is also removed by the crushed water particles.

In general, ultrasonic waves are delivered in the order of metal, liquid, and gas, and the materials constituting the installation are mostly metal, so vibration is transmitted to the entire installation through the metal. When ultrasonic waves are delivered to the water through the surface of the metal, numerous bubbles are generated and dissipated in the water, absorbing gaseous bodies in the water, repeating the explosion, and pulverizing the particles of the water. When it explodes, it releases tens of thousands of degrees of temperature, but the size of the air bubbles is so small that the temperature rise is very small.

On the other hand, the amount of air bubbles generated depends on the temperature and frequency of the water, the cavitation phenomenon will vary under the same frequency conditions, depending on the structure, thickness of the installation. When the particles in the water are pulverized by ultrasonic waves, the surface area of the particles is increased, the particles are bonded to the increased surface again, and the pulverization is repeated, and the particles are pulverized finely. In addition, when the ultrasonic wave is transmitted to the water through the metal, minute waves are generated between the water and the surface of the metal, thereby preventing the particles and the gas body from adhering to the surface of the installation and improving heat transfer by convection. When a wave propagates, energy is also propagated, and the rate of energy transfer is expressed as energy per unit area per unit time, which is called wave intensity.

For example, in the case of a three-dimensional wave, at any moment, the energy passing through a cross section per unit time becomes a unit of uniformity, which is divided by the cross section through the cross section, which is the intensity of the wave. In the case of two-dimensional waves, the unit length is calculated as passing through the unit length. In the case of one-dimensional waves, the cross section is only a point, and the energy per unit time defines the intensity of the wave.

In the case of sound as well as other three-dimensional wave can be represented as shown in the following equation (1).

Accordingly, the intensity of sound is expressed in units of W / m ² .

For waves that originate from a point and spread radially evenly, the distance occupied by the wave source increases and the space occupied by the wave becomes larger in proportion to the square of the distance. Therefore, the intensity I of the wave is inversely proportional to the square of the distance as shown in Equation 2 below.

Where P is the energy released per unit time in the wave source, and 4πR ₂ is the surface area of the sphere where the wave energy is stretched. Accordingly, the intensity of the wave at the point where the distance from the wave source is R ₁ and R ₂ is squared of the distance as shown in Equation 3 below.

As a rule, there are always cracks on the scale attached to the surface of the tube or metal. This is due to the difference in the coefficient of thermal expansion between the metal and the scale, and since the heat and boiler equipment is always accompanied by a change in temperature, a gap occurs in the process of repeated expansion and contraction.

In the process of ultrasonic waves being transferred to the water through the metal, the cavitation phenomenon discussed above affects the removal of the scale. The scale is crushed by the force of the bubbles exploding on the scale surface and moved by the flow of water or falls to the bottom of the plant.

2 and 3 show the relationship between the cavitation and pressure and the intensity and frequency of the cavitation sound pressure, respectively.

Referring to FIG. 2, it can be seen that bubbles are repeatedly generated and disappeared according to pressure. And, referring to Figure 3, the change in the intensity of the sound pressure does not appear in the frequency of 10 ^-2 to 1KHz, it can be seen that the sound intensity rapidly increases at 1KHz to 10 ³ KHz. In addition, it can be seen that the intensity of sound pressure is rapidly increased even if the frequency is not increased above 10 ³ KHz.

4 is a system configuration diagram of a scale removing apparatus according to an exemplary embodiment of the present invention, and FIG. 5 is a circuit configuration diagram of FIG. 4.

Referring to the drawings, the scale removing device includes an input power supply unit 10, a constant voltage circuit unit 11, a microcontroller unit 12, a switching circuit unit 13, a display unit 14, an RL series circuit unit 15, and a mixer unit ( 16), a magnetic field generating output section 18 consisting of an output terminal section (oscillation driving section) 17 and a coil wound pipe.

The input power of the input power supply unit 10 is supplied to the microcontroller unit 12 through the constant voltage circuit unit 11. The display unit 14 is controlled by the microcontroller unit 12 to select a desired frequency and output the digital signal. The transistor is driven using the digital signal, and as a result, a switching action and a transient phenomenon of RL are caused to output a desired ultrasonic output through the magnetic field generating output unit 18.

The input power supply unit 10 typically supplies 12V DC power, and the constant voltage circuit unit 11 configures a circuit using the constant voltage IC to supply the 12V voltage supplied from the input power supply unit 10 to the microcontroller unit 12. To supply.

In the control unit of the microcomputer, the oscillation unit, that is, the output terminal unit 17 and the display unit 14 are controlled using the microcontroller unit 12. The microcontroller unit 12 operates by oscillation of a 16 MHz crystal, and a simple reset circuit is formed by a combination of a switch and an electrolytic capacitor.

Single-frequency ultrasonic descaling devices vary greatly in power, depending on factors affecting resonance conditions, tube thickness, and water temperature. In order to solve this problem, the simultaneous multi-frequency, that is, to generate the ultrasonic waves of various frequencies of various bands. The low frequency has a strong cavitation strength, so that strong scale removal is possible, and the high frequency has a high penetration force, so that the scale of the curved surface such as the bent portion of the boiler tube can be effectively removed, thereby varying the output of the microcontroller unit 12. The ability to remove scale can be enhanced. In addition, the digital signal square wave is more excellent than the conventional analog system.

In addition, the output terminal portion (oscillation drive portion) 17 is to convert the square wave pulse generated by the micro-controller portion 12 into a sinusoidal waveform to control the power supply coming directly from the power supply device to output an output value higher than the input. In addition, in the present invention, by implementing the switching circuit section 13 and the RL series circuit section 15 to obtain a high output voltage, the switching action of the transistor and the transient phenomenon of the RL are applied.

The display unit 14 is configured with an LCD, and when selecting a frequency value, it is possible to visually check the frequency display and the operation state.

The magnetic field generating output unit 18 is manufactured by using the specific resistance value of the choke coil, and the length and the winding direction of the coil are important factors for determining the efficiency of the present invention. In general, the magnetic field generating output winds the coil of N turns in the magnetic circuit and passes the current of I [A] to H [AT / m] in the magnetic circuit and d [m to the minute line vector in the magnetic field. ] According to Ampere's law of weekly integral,

∮C · dℓ = NI [AT]

Is established. In this equation, the NI magnetic flux in the magnetic circuit

φ = BS = μHS [Wb]

Generates.

The current flowing through the coil is sinusoidal and varies from hundreds to thousands every second. Therefore, a large electromagnetic force can be obtained as compared with the magnetic force alone, and a strong force is applied to ion particles or water molecules in the water flowing inside the pipe.

6 is a flowchart of a frequency conversion control circuit for obtaining the digital waveform, which is programmed in the microcontroller unit 12.

Referring to FIG. 6, in step 100, a register and a port are initialized. In step 102, the repetition frequency of the output frequency and the repetition frequency of the output routine are set, and in step 104, the TMR0 interrupt is set. Subsequently, step 106 sets a conversion time of the LED, and in step 108, as an LED flickering step according to the output state, when it is not flickered, the process returns to the step 106.

7 is a flowchart related to a timer interrupt.

Referring to FIG. 7, in step 200, it is determined whether the start is 0, and the routine TMR0 routine of step 202 or the TMR1 routine of step 204 is performed. After performing step 202 or step 204, the process proceeds to step 206 to complete the interrupt, and proceeds to step 208 to return to the main routine.

8 is a flowchart related to timer 0.

Referring to FIG. 8, a pulse is output in step 300 and a frequency is changed in step 302. Subsequently, in step 304, it is checked whether the duty is increased, and if it is increased, the process proceeds to step 306 to increase the duty, and then, in step 308, the number of repetitions is detected. However, if it is not increased, the process proceeds to step 310 and the duty is reduced, and then the process proceeds to step 308.

If the number of repetitions in step 308 is three or more times, the process proceeds to step 312 and ends after setting the start select to 1, and ends if the number of repetitions is not three or more times.

9 is a flowchart related to timer 1. FIG.

Referring to FIG. 9, in operation 400, a pulse is output, and in operation 402, if the duty is increased, the operation proceeds to operation 404, increases to duty 10, and proceeds to operation 406. The number of repetitive outputs is detected. On the other hand, if the duty is not increased, the process proceeds to step 408 and decreases to duty 10, and then proceeds to step 406. In the case of 50 repeating outputs in step 406, the process proceeds to step 410 and ends after changing the group frequency.

As described above, in the present invention, by using a micro-controller to continuously output a digital signal square wave having a better performance than the conventional analog method, and by outputting ultrasonic waves from the magnetic field generating output unit by such a digital signal, It removes the scale formed inside the pipe of the heat exchanger more effectively. The result is a reduction in manpower and time wasted for descaling and a significant reduction in resource waste.

In addition, since the descaling apparatus according to the present invention is capable of various frequency conversion, there is an advantage that the scale can be removed according to the pipe thickness and hot water state and flow rate.

In addition, in the descaling device according to the present invention, by using the transient phenomenon of the switching circuit and the RL, it is possible to produce a large amount of expensive products using a conventional magnetostrictive oscillator at a low cost, water pollution due to the use of the cleansing agent and chemical customs agent There is an advantage that can solve the problem and noise problem.

Claims (4)

An input power supply unit to which a DC power source for driving each part of the circuit is input; A constant voltage circuit unit for causing a constant voltage to be applied from the input power supply unit; A microcontroller unit receiving input power from the constant voltage circuit unit to continuously output a digital signal square wave continuously; An output terminal unit for outputting an output value higher than an input by controlling a supply power directly coming from a power supply device by converting a square wave pulse generated by the microcontroller into a sine wave waveform; A display unit for displaying a frequency display and an operating state to select a frequency value outputted through the microcontroller unit; And The coil wound pipe outputs ultrasonic waves to remove scale and prevent adhesion again by applying powerful force to ion particles or water molecules in the water flowing inside the pipe by the digital signal output from the microcontroller. Descaler characterized in that it comprises a magnetic field generating output. The descaling device of claim 1, further comprising a switching circuit portion and an RL series circuit portion for high output voltage and various frequency changes. Generating an ultrasonic wave by a digital signal using a microcontroller and firing the ultrasonic wave on a boiler tube in which a scale is generated; Contracting and expanding by sound pressure alternately in the water from the emitted ultrasonic wave, causing waves to propagate in the water to generate and extinguish tens of millions of fine air bubbles; And separating and removing the scale generated on the surface of the boiler tube by the strong energy generated during the bursting of the air bubbles and preventing the new scale from adhering to the surface. The method of claim 3, wherein the digital waveform, Initializing registers and ports of the microcontroller; Setting a repetition frequency of an output frequency and a repetition frequency of an output routine; Setting a TMR0 interrupt and setting a conversion time of the LED; A method of descaling, characterized in that obtained by the step of checking the blinking LED according to the output state.