JPS6023794A - Heat exchange device - Google Patents

Abstract

PURPOSE:To prevent scale from adhering to a heat transfer tube or a fluid carrying pipe by a method wherein a supersonic transducer is provided so as to contact with one of fluid near a heat transfer body having two kinds of different flow paths and an alternative electric power is supplied to the transducer. CONSTITUTION:The fluid 11 enters from an inlet port 2 and flows out of a discharging port 3. Another fluid 12 enters from the inlet port 4 and flows out of the discharging port 5. The supersonic transducer 7 is provided on the outer tube 6 near the heat transfer tube 1 so as to contact with the fluid 12 and high- frequency electric power is supplied continuously or intermittently to the transducer from an oscillating amplifier 10 through terminals 8, 9. Electric energy from the oscillating amplifier 10 oscillates the fluid 12 as a supersonic wave. The oscillated fluid 12 causes the supersonic vibration of the heat transfer tube 1 and the fluid 11 in the heat transfer tube 1 is oscillated by the propagation of the supersonic vibration, then, the supersonic vibration of all tubular body walls, such as the outer tube or the like, which are contacting with the fluid 12, are caused. According to the vibration, the scale of the heat transfer tube elutes out into the fluid as sludge without adhering to the heat transfer tube or the vicinity thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heating/cooling device for hot spring water, underground water, seawater, tap water, etc. (hereinafter referred to as fluid).

Conventional structure and its problems Problems that prevent stable operation of heating and cooling equipment used for industrial or general purposes include scale adhesion to heat transfer tubes or transfer tubes, resulting in an increase in fluid transfer resistance, and a decrease in heat exchange efficiency. There are problems with deterioration and corrosion of the can body. These scale deposits significantly impede the thermal economy in equipment operation, so countermeasures are an important issue. In particular, scale in the heat exchange parts of heating and cooling equipment causes a significant drop in heat exchange efficiency.Furthermore, heat exchangers have complicated shapes to increase the heat transfer area, and once scale has adhered, it is difficult to remove it. However, regular maintenance and costs such as chemical or physical methods are required. Conventional methods for preventing scale deposition include adding acid to precipitate and remove scale components, adjusting the pH of raw water to change the limit point of scale precipitation, or adding an inhibitor to remove scale components. There are methods such as maintaining supersaturation, turning the components into sludge, or adding seed crystals and using them as nuclei to precipitate scale components. However, all of these methods involve dripping or mixing a relatively large amount of medicinal materials into water, which requires a large amount of mechanical means and consumables. Against this background, the problem of scale has become a bottleneck in the development of systems intended to reduce fossil energy by using hot spring hot water to heat buildings and agricultural facilities, and maintenance is labor-intensive. There is an urgent need to develop a method that does not require additional costs and does not incur regular consumable costs.

Purpose of the Invention The present invention has been developed based on the above-mentioned background.
It is intended to provide a heating and cooling system that prevents scaling on heat transfer tubes or fluid transfer tubes in a cooling system without incurring routine maintenance effort and consumables costs.

Structure of the Invention The present invention excites the fluid flowing through a heat exchanger tube or a conveyor tube with ultrasonic energy, changes the supersaturation conditions of scale components in the fluid, and reduces the saturation degree of the fluid due to cooling of the fluid by the tube. In addition, scale components can be removed by the combined effect of ultrasonic excitation, such as promoting scale precipitation by ultrasonic excitation, and preventing scale precipitation on the pipe body using sonic energy 1-1, or peeling off scale that has already adhered to the pipe body. This heating and cooling device is characterized by depositing sludge in a fluid without adhering to the body, and removing the sludge as a precipitate.

Description of examples An embodiment of the present invention will be described in detail below.

The figure is a schematic diagram of a heating and cooling device for a heat exchanger, which is an embodiment of the present invention. The heat exchanger has a plurality of heat exchanger tubes 1, and a fluid 11 to be heat exchanged is introduced from an inlet 2 and passes through the heat exchanger tubes 1.
After heat exchange is performed, the water is discharged from the discharge port 3. - The fluid 12 is introduced from the inlet 4 without mixing with the power fluid 11, and after exchanging heat with heat transfer #1, it is discharged from the outlet 5. One method is the outer tube near the heat tube 1. 6, an ultrasonic transducer 7 is installed in contact with the fluid 12.High frequency power is continuously or intermittently supplied to the transducer 7 from an oscillation amplifier 10 through terminals 8.9. The transducer 7 consists of a vibrator that generates ultrasonic vibrations using high-frequency power and a diaphragm bonded to the vibrator.
The electrical energy from the oscillation amplifier 1o is converted into ultrasonic waves,
Excite fluid 2. The excited fluid 2 further causes the heat exchanger tube 1 to vibrate ultrasonically, which propagates to excite the fluid 2 inside the heat exchanger tube 1, and also causes all tube walls such as the outer tube that come into contact with the fluid 2 to vibrate ultrasonically. The vibrator is preferably a ferroelectric material such as barium titanate or lead zirconate titanate, or a ferrite magnetostrictive element.

Using these ultrasonic energies, for example, when hot spring water is used as the fluid 11 and water is used as the fluid 12, the scale that is normally deposited on the tube walls that are in contact with the heat exchanger tube 1 and other fluids 11 is peeled off, or the scale that is deposited in the fluid is removed. Let it precipitate. The scale deposited in these fluids is discharged as sludge from the discharge port 3, and a settling tank can be installed and removed as necessary. In this manner, according to the present invention, the scale of the heat exchanger tube, which is extremely difficult to remove once precipitated, can be washed away as sludge in the fluid without adhering to the vicinity of the heat exchanger tube.

On the other hand, the principle of preventing scale adhesion is the same when hot spring water is used as fluid 12 and water is used as fluids 11 and 1 to 1. However, in this case, fluid 2, which has a large scale component, is in direct contact with the transducer 7. The effect is noticeable in four ways. These effects are not limited to hot spring water, but also apply to fluids such as groundwater and heated seawater.

Hereinafter, specific effects of the present invention will be described in Examples.

In the example, the alkalinity is about 1600m! 17/e
Approximately 70° of calcium hardness of approximately 1,000 UJjj/l
10 m5/hour of hot spring water of C was used as the fluid of a fixed length tube plate type heat exchanger whose principle configuration is shown in the figure, and a static flow of water of M- was used as fluid 12. Heat exchanger tube 1 has an outer diameter of approximately 25111 Ja
36 of them were installed in front of the row having a diameter of about 400 mm. On the other hand, two transducers with an ultrasonic output of 1.5 KW are installed on the inner wall of the outer tube surrounding the heat exchanger tube 1 near the inlet and outlet of the outer tube, respectively, and the oscillation amplifier 10 generates a frequency of about 30 KHz. It was designed to supply high frequency power. Under these installation conditions, hot spring water was continuously supplied and the effectiveness of the device of the present invention was evaluated by observing the degree of scale adhesion to the heat transfer tubes when the device of the present invention was used and in the conventional case where the device of the present invention was not used. can be evaluated.

In the example, the fluid 1
We checked the static pressure loss and heat exchange rate due to the diameter reduction in the heat transfer tube due to the scale of 2 (hot spring water). As a result, in about 16 days under conventional operating conditions, the heat exchange rate drastically decreased compared to the initial level due to scale adhesion, and due to an increase in static pressure loss resistance,
It no longer functions as a heat exchanger. - Under the operating conditions of the device invented by Rikiki, no significant drop in heat exchange rate or static pressure loss was observed even 16 days after the start of operation, and the function of the heat exchanger was continuously demonstrated even after long-term operation. The remarkable effects of the present invention were recognized.

The above example uses hot spring water that has a relatively large scale component, but for fluids that have a lower scale component than hot springs, such as groundwater and industrial water, it is necessary to reduce the ultrasonic output or apply ultrasonic excitation. By setting the time interval longer, it is possible to further reduce equipment costs and reduce operating power. Furthermore, although this embodiment has been described with reference to a fixed multi-tube and plate type heat exchanger, it is clear that the effects of the present invention can be exerted when used in plate-fin type heat exchangers and other heat exchangers.

Effects of the Invention As described above, the present invention arranges a heat transfer body so that the fluids flowing through two different flow paths exchange heat with each other without mixing with each other, and when one of the fluids near the heat transfer body This is a heat exchange device in which an ultrasonic transducer is installed in contact with the ultrasonic transducer and alternating power is supplied to the ultrasonic transducer. It can prevent scale from adhering to heat pipes and conveying pipes, prevent energy loss due to a decrease in heat exchange rate mainly caused by scale, and increase in fluid conveyance power due to increased static pressure loss, and prevent the use of everyday chemicals. Since scale adhesion can be prevented without using consumables, equipment costs, daily maintenance costs, and consumables costs required for scale prevention can be greatly reduced. It has remarkable effects on the effective use of water and hot spring water as energy, as well as on improving efficiency and reducing costs in seawater desalination equipment, and has not only economic effects but also social effects in terms of energy saving technology. .

[Brief explanation of drawings]

The figure is a sectional view showing an embodiment of a heat exchange device according to the present invention. 1... Heat exchanger tube, 2.4... Inlet, 3.6
... Mountain discharge port, 6 ... Heat exchanger outer tube, 7 ...
... Ultrasonic transducer, 8, 9... Mountain terminal,
1o...Oscillation amplifier, 11.12° mountain fluid.

Claims (1)

[Claims] (G) A heat transfer body is arranged so that two types of fluids having different flow paths can exchange heat with each other without being mixed with each other,
A heat exchange device characterized in that an ultrasonic transducer is installed in contact with one of the fluids near the heat transfer body, and alternating power is supplied to the ultrasonic transducer. (2) The heat exchange device according to claim 1, wherein the ultrasonic transducer is a ferroelectric vibrator. (3) The heat exchange device according to claim 1, wherein the ultrasonic transducer is a ferromagnetic vibrator. (4) The heat exchange device according to claim 1, wherein alternating power is supplied intermittently.