KR20160066453A - Heat exchanger - Google Patents

Abstract

The present invention relates to a heat exchanger and, more specifically, to a heat exchanger which can efficiently remove foreign substances and scale without decomposition of components or an operation stop of the device. The heat exchanger includes: a case having an inlet and an outlet on both sides in order for a first fluid to be heat-exchanged after the first fluid flows inside; an inner pipe enabling heat exchange between the first fluid and a second fluid by providing a flow path of the second fluid which has a different temperature property from the first fluid, wherein a linear pipe unit installed in the case is connected to a curve pipe unit protruding to the outside of the case; a scraper with a predetermined width, moving along the outer circumference of the linear pipe unit and moving a third fluid of a high pressure between the linear pipe units; and a driving unit moving the scraper along the outer circumference of the linear pipe unit.

Description

Heat Exchanger {HEAT EXCHANGER}

The present invention relates to a heat exchanger capable of effectively removing scales and foreign matter on the surface of a tube without stopping operation of the apparatus or disassembling parts.

Heat Exchanger is a device that conducts heat exchange between fluids by directly or indirectly contacting two low temperature and high temperature fluids with different temperature. It is widely used in industrial process, heating, hot water, cooling water heat exchange, do.

The heat exchanger is roughly divided into an indirect contact heat exchanger, a regenerative heat exchanger, and a direct contact heat exchanger according to a heat transfer method.

The indirect contact type heat exchanger is a system in which two fluids are indirectly transferred by fluid convection on the surface of the diaphragm while being separated from each other by a diaphragm or the like and the regenerative heat exchanger is a system in which heat is transferred by using a solid heat storage medium , And the direct contact type heat exchanger is a system in which two fluids are brought into direct contact and heated.

In the indirect heat exchanger of the heat exchanger, heat exchange is performed through a heat transfer surface, which is a heat exchange area between fluids, and a heat plate or metal tube having a generally excellent thermal conductivity is formed in a double or bundle shape on the heat transfer surface.

When the indirect contact type heat exchanger is used for a long time, microorganisms, dust, etc. in the atmosphere are deposited on the heat plate or the tube surface with scales and foreign substances. As a result, the cross-sectional area of the flow path of the pipe is reduced and the flow rate is reduced, so that the heat exchange and cooling efficiency are remarkably lowered and the mechanical life is shortened.

Therefore, it is essential to periodically clean the heat exchanger in order to remove scales and foreign substances deposited on the heat plate or the tube surface.

Korean Patent No. 467,791 discloses a heat exchanger in which a plurality of vertical heat transfer tubes are bundled in a cylindrical body and a mixed fluid composed of water and solid particles is sprayed on the surface of the vertical heat transfer tube to remove scales and foreign substances .

This technique requires stopping the operation of the apparatus in order to clean the heat exchanger, and since the water used as a cleaning means generally contains ionic substances such as dissolved oxygen, Ca, Mg, etc., which cause corrosion of the tubes, The inner temperature is lowered and the ion material is eluted, so that the phenomenon of being deposited on the surface of the tube occurs in scale.

In addition, although a technique of using a particulate material in which water and compressed air are mixed as the cleaning means has been disclosed, the particulate material is still present in the presence of an ionic material, so that deposition of scale and foreign matter still occurs.

Accordingly, in order to completely remove scales and foreign substances, the internal parts of the heat exchanger must be disassembled to clean the pipe. In this case, there is a disadvantage in that a large number of work forces are input and a working time is extremely long.

In order to solve the above problems, the present invention relates to a heat exchanger having improved working efficiency by effectively removing scales and foreign substances on the tube surface without stopping operation of the apparatus or disassembling internal parts.

In order to achieve the above object, according to the present invention, there is provided a refrigerator including: a case having an inlet and an outlet formed on both sides of the first fluid to be heat-exchanged after the first fluid flows therein; Wherein the bending portion is protruded to the outside of the case and the straight pipe portion is installed inside the case and provides a flow path of a second fluid having a temperature characteristic different from that of the first fluid to provide a flow path between the first fluid and the second fluid, An inner pipe allowing heat exchange to the inner pipe; A scraper of a predetermined width moving along an outer circumferential surface of the straight pipe portion and capable of moving a high pressure third fluid between the straight pipe portions; And driving means for moving the scraper along an outer circumferential surface of the straight pipe portion.

The driving means may include a chain fixed to both ends of the case and lifting the scrapers along the outer peripheral surface of the straight pipe portion.

The driving means may include an ejection pipe provided with a plurality of nozzles for ejecting a high-pressure third fluid to the scraper.

The heat exchanging device may further include a housing for receiving a bend portion protruding from the case.

The high-pressure third fluid may be high-pressure air.

The heat exchanger according to the present invention has an advantage that scale and foreign matter can be effectively removed on the tube surface without stopping the operation of the apparatus, thereby maximizing heat exchange and cooling efficiency.

Further, the heat exchanger according to the present invention has an advantage of reducing the scale and foreign matter on the surface without disassembling the internal parts, thereby shortening the working time, minimizing the work space, and reducing the maintenance cost due to the labor saving and removing work.

Further, the heat exchanger according to the present invention is capable of preventing a driving failure such as occurrence of additional cost due to deformation damage of a component during the process of disassembling, cleaning of a chemical tank, assembly after assembly, There is an advantage.

1 is a schematic view of a heat exchanger according to an embodiment of the present invention,
2 is a schematic view of a heat exchanger according to another embodiment of the present invention.

The present invention relates to a heat exchanger capable of effectively removing scales and foreign matter deposited on a tube surface and maximizing heat exchange and cooling efficiency.

Hereinafter, a heat exchanger according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic view of a heat exchanger according to an embodiment of the present invention.

1, a heat exchanger 10 according to the present invention is a tubular device for indirectly contacting two fluids to move heat between fluids, and includes a casing 20, an inner pipe 30, a scraper 40, (50).

More specifically, the heat exchanger (10) comprises a case (20) having an inlet (21) and an outlet (22) on both sides for heat exchange after the first fluid flows into the interior; The bending portion 32 is protruded to the outside of the case 20 and the straight pipe portion 31 is installed inside the case 20 and the first fluid 31 and the bending portion 32 are connected to each other, An inner tube (30) providing a flow path of a second fluid having a different temperature characteristic to enable heat exchange between the first fluid and the second fluid; A scraper 40 having a predetermined width that moves along the outer circumferential surface of the straight pipe portion 31 and is capable of moving a high pressure third fluid between the straight pipe portions 31; And driving means (50) for moving the scraper (40) along the outer peripheral surface of the straight pipe portion (31).

The first fluid and the second fluid that are heat-exchanged in the present invention can be applied without limitation to those commonly used in the art. For example, the first fluid is a high-temperature fluid such as hot water, steam, lubricant, May be a low temperature fluid having a relatively lower temperature than a high temperature fluid such as water, seawater, or refrigerant.

The case 20 constituting the heat exchanger 10 of the present invention is for protecting each component of the heat exchanger 10 and preferably has a closed structure in order to prevent foreign substances from being injected from the outside.

The shape of the case 20 can be changed according to the use and the space of the heat exchanger 10, and for example, the cross section may be a square or a circle.

The inlet (21) and the outlet (22) are formed on both sides of the case (20). The first fluid flows into the case 20 through the inlet 21 and flows along the inner tube 30 to be described later. Then, the first fluid is heat-exchanged with the second fluid and is discharged to the outlet 22.

An inner tube 30 is formed in the case 20. The inner tube 30 has a plurality of turns in a spiral shape in which the straight tube portion 31 and the bending portion 32 are repeatedly connected. At this time, a gap is formed between adjacent turns and turns, and the gap can be uniformly formed over the entire inner tube 30.

It is preferable that the width of the clearance is such that the scale of the scraper 40, which will be described later, and the removability of the foreign substances are easily made, and the heat exchange efficiency can be increased.

The bending portion 32 is protruded to the outside of the case 20 and the straight pipe portion 31 is installed inside the case 20 because the bending portion 32 is immersed in the surface of the inner pipe 30 only by vertical movement of the scraper 40 Scales, foreign substances, and the like.

Such an inner tube 30 provides a flow path of the second fluid having a temperature characteristic different from that of the first fluid.

Specifically, an inlet port 33 and an outlet port 34 are formed on both sides of the inner pipe 30, and the second fluid flows into the case 20 through the inlet port 33 and then flows into the outlet port 34 .

At this time, the inner tube 30 is made of at least one material selected from the group consisting of copper, iron and stainless steel having excellent thermal conductivity so that the heat of the second fluid flowing in the inner tube 30 can be efficiently discharged. .

Therefore, the first fluid flows through the inlet 21, flows along the inner tube 30, and is heat-exchanged with the heat of the second fluid flowing in the inner tube 30, thereby finally recovering thermal energy. The heat energy thus recovered is used as a cooling and heating device for boilers, wastewater treatment plants, dyeing plants, power plants, ships, incinerators, etc., which are heated by combustion gases.

However, the first fluid introduced into the case 20 during the heat exchange process contains scales and foreign substances, and such scales and foreign substances adhere to the surface of the inner pipe 30 and are deposited thereon. Accordingly, there is a problem that the heat released from the inner pipe 30 is blocked to lower the heat exchange and cooling efficiency.

In the present invention, in order to remove scales and foreign substances deposited on the surface of the inner tube 30, the inner tube 30 is moved in the heat exchanger 10 along the outer peripheral surface of the straight tube portion 31, And a scraper 40 having a predetermined width capable of moving the third fluid of the second fluid.

The scraper 40 vertically moves along the outer peripheral surface of the straight pipe portion 31 to scrape scale and foreign matter deposited on the surface of the straight pipe portion 31 and simultaneously move the high pressure third fluid into the scraper 40 To remove residual scale and foreign matter.

The scraper 40 is formed with a hollow portion having a predetermined width to receive the third fluid therein. At this time, the width and length of the scraper 40 can be appropriately changed according to the flow path width and length of the straight pipe portion 31.

The high-pressure third fluid is not particularly limited as long as it is a removal means commonly used in the art, but may be, for example, high-pressure air.

In order to prevent the temperature of the heat exchange between the first fluid and the second fluid from being lowered, it is preferable that the high-pressure air is preheated and supplied by using another air supply means before being blown into the scrapers 40. The preheating temperature is preferably controlled in a manner similar to the temperature of the incoming gas. For example, the preheating temperature may be 450 to 550 ° C for a coal-fired power plant.

The scraper 40 is moved along the outer peripheral surface of the straight pipe portion 31 by the driving means 50. The driving means 50 is fixed to both ends of the case 20, And a chain 53 for moving up and down the scraper 40 along the longitudinal direction.

More specifically, the drive means 50 has a frame 51 of a rectangular frame and a hydraulic motor 52 at one end of the frame 51. The shaft of the hydraulic motor 52 and the hydraulic motor 52 And the sprockets 53a and 53b are formed at the other ends of the unformed frame 51. The two structures may be fixed to both ends of the case 20. [

The sprockets 53a and 53b formed on the same shaft are wound by a chain 54. The scrapers 40 are fixed to the chain 54 so that the scrapers 40 are driven by the hydraulic motor 52, Is vertically moved along the outer circumferential surface of the straight pipe portion 31.

In addition, although not shown in the drawing, the driving means 50 may include an ejection pipe provided with a plurality of nozzles for ejecting a high-pressure third fluid to the scraper 40.

It is preferable that the ejection pipe has a nozzle shape, that is, the size of the hole decreases from the inside toward the outside, thereby improving the spraying force. Further, it is preferable that the ejection pipe is uniformly formed in the circumferential direction so that the third fluid is uniformly sprayed to the scraper 40.

2 is a schematic view of a heat exchanger according to another embodiment of the present invention.

As shown in FIG. 2, the heat exchanger 10 according to another embodiment of the present invention may further include a housing 60 that receives the bending portion 32 protruding from the case 20.

The housing 60 is not particularly limited as long as it has a shape and size capable of accommodating the bending portion 32. The shape and size of the housing 60 may be changed according to the case 20. [

As described above, the heat exchanger 10 according to the present invention includes a scraper 40 to scrape scales and foreign matter deposited on the surface of the straight pipe portion 31 of the inner pipe 30, and at the same time, 40), it is possible to effectively remove residual scale and foreign matter.

In addition, in the related art, it is necessary to stop the operation of the apparatus when the heat exchanger is cleaned. However, the heat exchanger according to the present invention can reduce scales and foreign substances during operation of the apparatus.

In addition, it is possible to remove the scales and foreign substances on the surface of the tube without disassembling the internal parts, so that it is possible to prevent deformation of components that may occur in the process of disassembling parts in the conventional heat exchanger cleaning method, And occurrence of leaking due to abnormality in connection after cleaning and washing can be prevented.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention. Such variations and modifications are intended to be within the scope of the appended claims.

Example  One

A case, a heat exchanger (in the case of a coal-fired power plant) of Fig. 1 including an inner pipe connected to the straight pipe portion and the bending portion, a scrapper moving along the outer peripheral surface of the straight pipe portion, and a driving means for moving the scrapper were prepared. In the case of the heat exchanger, combustion gas having a temperature of about 500 to 600 ° C was introduced into the case, and water having a temperature of about 15 ° C was introduced into the inner tube to repeatedly perform heat exchange between the combustion gas and water. Then, after 6 months passed, the scraper was moved along the outer circumferential surface of the straight pipe portion by the driving means to remove scale and foreign matter deposited on the surface of the straight pipe portion, and at the same time, the high pressure air was sprayed at a speed of 2 m / And the scale of the straight pipe portion and the foreign matter removal were performed for 30 minutes.

As a result of visually observing the removed state of the straight pipe portion, it was confirmed that the scale and foreign substances deposited on the surface of the straight pipe portion were almost completely removed. Therefore, it has been found that the heat exchanger according to the present invention improves the removal efficiency of scales and foreign substances by using scrapers and high-pressure air without stopping the operation of the apparatus or disassembling internal parts.

Comparative Example  One

The same procedure as in Example 1 was carried out except that water having a temperature of 15 ° C was sprayed at a high pressure without using a scraper and high-pressure air, and the straight pipe portion was cleaned for 30 minutes.

As a result of visually observing the cleaning state of the straight pipe portion, scale and foreign substances deposited on the surface of the straight pipe portion were partially desorbed, and it was confirmed that scale and foreign matters were more deposited on a part thereof. It can be seen that as the temperature is lowered, the ionic substance contained in the particulate matter is eluted to the outside and deposited on the surface of the straight pipe portion, thereby accelerating the deposition phenomenon.

10: Heat exchanger
20: Case
21: inlet of the first fluid
22: outlet of the first fluid
30: Inner pipe
31:
32:
33: inlet of the second fluid
34: outlet of the second fluid
40: scraper
50: driving means
51: frame
52: Hydraulic motor
53a, 53b: Sprocket
54: Chain
60: Housing

Claims (5)

A case having an inlet and an outlet formed on both sides of the first fluid to be heat-exchanged after the first fluid flows into the interior;
Wherein the bending portion is protruded to the outside of the case and the straight pipe portion is installed inside the case and provides a flow path of a second fluid having a temperature characteristic different from that of the first fluid to provide a flow path between the first fluid and the second fluid, An inner pipe allowing heat exchange to the inner pipe;
A scraper of a predetermined width moving along an outer circumferential surface of the straight pipe portion and capable of moving a high pressure third fluid between the straight pipe portions;
And driving means for moving the scraper along the outer peripheral surface of the straight pipe portion.
The heat exchanger according to claim 1, wherein the driving means includes a chain fixed to both ends of the case and lifting the scrapers along the outer peripheral surface of the straight pipe portion.
The heat exchanger according to claim 1, wherein the driving means includes an ejection pipe provided with a plurality of nozzles for ejecting a high-pressure third fluid to the scraper.
[Claim 4] The heat exchanger of claim 1, wherein the heat exchanger further comprises a housing accommodating a bend portion protruding from the case.
The heat exchanger according to any one of claims 1 to 4, wherein the high-pressure third fluid is high-pressure air.

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