JP7045230B2 - How to operate the open rack heat exchanger and the open rack heat exchanger - Google Patents

Description

The techniques disclosed herein relate to an operating method of an open rack heat exchanger and an open rack heat exchanger.

Patent Document 1 describes an open rack type vaporizer as one of the open rack type heat exchangers. In the open rack type vaporizer, a plurality of heat transfer tubes made of aluminum alloy are arranged side by side to form a heat exchange panel, and liquefied natural gas is allowed to flow in each heat transfer tube, and seawater as a heat medium is allowed to flow down on the surface of the heat exchange panel. ..

In order to prevent corrosion of the heat transfer tube and the lower header tube to which the lower end of the heat transfer tube is connected, in the open rack type vaporizer of Patent Document 1, the heat transfer tube or the like is placed on the surface of the heat transfer tube or the surface of the lower header tube. It forms a sacrificial anode layer made of a more base metal. The sacrificial anode layer is formed, for example, by thermal spraying. Further, the sacrificial anode layer may be composed of a clad material that covers the outer periphery of the heat transfer tube.

Japanese Unexamined Patent Publication No. 2008-240070

However, the sacrificial anode layer formed in the heat transfer tube and lower header tube is mechanically worn (corroded) by sand, shells, etc. contained in seawater while the open rack heat exchanger is in operation. , It is worn out by being chemically corroded by contact with seawater. Furthermore, the combined action of erosion and corrosion may cause severe wear of the sacrificial anode layer.

When the sacrificial anode layer is worn, the sacrificial anode layer is repaired by thermal spraying. If the sacrificial anode layer is easily worn, the frequency of repairing the sacrificial anode layer increases, and the maintainability of the open rack heat exchanger deteriorates.

The technique disclosed herein has been made in view of this point, and an object thereof is to suppress wear of a sacrificial anode layer in an open rack heat exchanger.

The inventor of the present application causes the heat medium to not directly and continuously hit the sacrificial anode layer when ice is adhered to the surface of the heat exchange section while the open rack heat exchanger is in operation. We have found that it is possible to suppress layer wear, and have completed the technology disclosed here.

Specifically, the technique disclosed herein relates to an operation method of an open rack type heat exchange device including a heat exchange unit for heating a low temperature liquid or gas and a supply unit for supplying a heat medium to the heat exchange unit. ..

The heat exchange section includes a lower header tube through which a low-temperature liquid or gas flows, a plurality of heat transfer tubes whose lower ends are connected to the lower header tube, and a heat transfer medium flowing down along the surface thereof, and the heat transfer tube. The upper end is connected and has an upper header tube through which the heated fluid flows in the heat transfer tube, and the heat exchange section has a sacrificial anode layer formed on at least a part of the surface.

The operation method of the open rack heat exchange device includes a step of adjusting the supply amount of the low temperature liquid to the lower header tube and a heat exchange section so that ice adheres to the surface of the heat exchange section. It includes a step of adjusting the supply amount of the heat medium.

Here, the open rack heat exchanger may be a vaporizer that heats a low-temperature liquid to make it a gas, or may be a heater that raises the temperature of the low-temperature liquid or gas. Further, the sacrificial anode layer may be formed on the entire heat exchange portion, or may be formed at least on a portion that touches or may touch the heat medium.

If ice adheres to the surface of the heat exchange part, the heat medium (for example, seawater) flowing down along the heat transfer tube hits the surface of the ice because the ice is on the sacrificial anode layer, but the surface of the lower header tube. It becomes difficult for the heat medium to directly hit the sacrificial anode layer formed on the surface of the heat transfer tube. If ice adheres to the surface of the heat exchange section during the operation of the open rack heat exchange device, it is possible to prevent the sacrificial anode layer from being worn due to erosion or corrosion, or the combined action of erosion and corrosion. Will be done.

As an example, the thickness of the ice attached to the surface of the heat exchange portion may be 0.5 mm or more. According to the study of the inventor of the present application, if the thickness of the ice is 0.5 mm or more, the sacrificial anode layer can be effectively protected.

By adjusting the amount of heat medium supplied to the heat exchange section so that ice adheres to the surface of the heat exchange section, wear of the sacrificial anode layer is suppressed, so the frequency of repairing the sacrificial anode layer is reduced, and the open rack The maintainability of the type heat exchanger is improved.

In the operation method of the open rack type heat exchange device, when the ice on the surface of the heat exchange portion becomes a predetermined thickness or less, the ice adhering to the surface of the heat exchange portion increases, so that the heat exchange portion is subjected to the heat exchange portion. By reducing the supply of heat medium , the thickness of the ice is maintained at a predetermined thickness .

Conventionally, when ice adheres to the surface of the heat exchange part, the heat transfer area decreases and the heat transfer performance of the heat exchange part deteriorates. Therefore, the heat exchange part tends to have no ice attached to the surface of the heat exchange part. The amount of heat medium supplied to the heat transfer unit was adjusted, specifically, the amount of heat medium supplied to the heat exchange unit was increased.

On the contrary, in this configuration, when the ice on the surface of the heat exchange section becomes less than a predetermined thickness, the supply amount of the heat medium to the heat exchange section is reduced. The "predetermined thickness" may be, for example, zero. Further, the "predetermined thickness" may be 0.5 mm as described above. When there is no ice on the surface of the heat exchange section or the thickness of the ice is less than the predetermined thickness, the amount of heat input to the heat exchange section is reduced by reducing the amount of heat medium supplied to the heat exchange section. The temperature drops. As a result, ice can be attached to the surface of the heat exchange portion, or the ice attached to the surface can be thickened. By maintaining the state in which ice adheres to the surface of the heat exchange portion during the operation of the open rack heat exchange device, it is possible to effectively suppress the wear of the sacrificial anode layer.

In order to "increase the amount of ice adhering to the surface of the heat exchange part", when the ice does not adhere to the surface of the heat exchange part, the ice adheres and the ice adheres to the surface. Includes both thickening the ice when it is attached.

In the method of operating the open rack heat exchange device, the amount of heat medium supplied to the heat exchange unit may be adjusted so that ice adheres to the surface of the lower header tube.

Since the heat medium flowing down the heat transfer tube vigorously collides with the surface of the lower header tube to which the lower end of the heat transfer tube is connected, the sacrificial anode layer is easily worn. When ice adheres to the surface of the lower header tube, wear of the sacrificial anode layer provided on the surface of the lower header tube can be effectively suppressed.

More specifically, the amount of heat medium supplied to the heat exchange section may be adjusted so that ice adheres to the upper surface of the lower header tube. The upper portion of the lower header tube may be, for example, an upper semicircle in the cross section of the lower header tube. Since the upper part of the lower header tube is more easily exposed to the heat medium than the lower part of the lower header tube, the sacrificial anode layer is more easily worn than the lower part. By adhering ice to the upper surface of the lower header tube, it is possible to effectively protect the portion of the lower header tube where the sacrificial anode layer is likely to wear.

Further, in the open rack type heat exchange device, the low temperature liquid may be heated in the heat transfer tube in the heat exchange section, and the lower header tube does not greatly contribute to the heating of the low temperature liquid. Therefore, adhering ice to the surface of the lower header tube has little effect on the performance of the open rack heat exchanger. That is, in the open rack heat exchanger, it is acceptable for ice to adhere to the surface of the lower header tube.

Even if the amount of heat medium supplied to the heat exchange section is adjusted so that ice adheres to the connection portion between the heat transfer tube and the lower header tube in the operation method of the open rack type heat exchange device. good.

The heat medium flowing down along the surface of the heat transfer tube tends to collect at the connection portion between the heat transfer tube and the lower header tube, and the sacrificial anode layer is easily worn due to the turbulence of the flow. By adhering ice to the connecting portion, wear of the sacrificial anode layer provided on the connecting portion can be effectively suppressed.

Further, since the connection portion between the heat transfer tube and the lower header tube does not greatly contribute to the heating of the low temperature liquid, it is acceptable for ice to adhere to the connection portion in the open rack heat exchange device.

In the open rack heat exchange device having the above configuration, the low temperature liquid flows in the lower header tube and the heated fluid flows in the upper header tube, so that the lower part of the heat exchange section has a relatively low temperature, and the heat exchange section has a relatively low temperature. The upper part of is relatively hot. Ice tends to adhere to the lower header tube and / or the connection portion between the heat transfer tube and the lower header tube. The open rack heat exchange device having the above configuration is advantageous in preventing the portion where the sacrificial anode layer is easily worn by the ice adhering to the surface.

The heat transfer tube has a tubular main body and a plurality of heat radiation fins protruding outward from the outer peripheral surface of the main body, and in the operation method of the open rack heat exchange device, the heat radiation fins and the heat radiation fins are used. The amount of heat medium supplied to the heat exchange section may be adjusted so that ice adheres to the valley between the sections.

In a heat transfer tube having a plurality of heat transfer fins, the heat medium flowing down along the surface of the heat transfer tube tends to collect in the valley between the heat radiation fins, and as a result of the flow being disturbed, the sacrificial anode layer is worn. Cheap.

Therefore, by adhering ice to the valley portion of the heat transfer tube, it is possible to suppress the wear of the sacrificial anode layer in the valley portion.

In the open rack heat exchange device, the amount of heat medium supplied to the heat exchange section is adjusted so that the height of the ice adhering to the valley portion is 300 mm or more from the lower header tube. May be good.

Since the heat medium hits the lower part of the heat exchange part more vigorously than the upper part, the sacrificial anode layer is more likely to be worn at the lower part of the heat exchange part than at the upper part. By adhering ice to the valley portion at least up to a height of 300 mm from the lower header tube, wear of the sacrificial anode layer provided in the valley portion can be effectively suppressed.

As described above, since the lower part of the heat exchange part has a relatively low temperature and the upper part of the heat exchange part has a relatively high temperature, ice is more likely to adhere to the lower part even in the valley part of the heat transfer tube. Therefore, it is possible to efficiently suppress the wear of the sacrificial anode layer provided in the valley portion.

The open rack heat exchange device disclosed herein includes a heat exchange unit that heats a low-temperature liquid or gas, and a supply unit that supplies a heat medium to the heat exchange unit.

The heat exchange section includes a lower header tube through which a low-temperature liquid or gas flows, a plurality of heat transfer tubes whose lower ends are connected to the lower header tube, and a heat transfer medium flowing down along the surface thereof, and the heat transfer section. The upper end of the heat tube is connected and has an upper header tube through which the heated fluid flows in the heat transfer tube, and the heat exchange section has a sacrificial anode layer formed on at least a part of the surface. The supply unit is configured to adjust the amount of heat medium supplied to the heat exchange unit so that ice adheres to the surface of the heat exchange unit.

According to this configuration, similarly to the above, the ice adhering to the surface of the heat exchange portion protects the sacrificial anode layer, so that the sacrificial anode layer can be prevented from being worn.

The supply unit reduces the amount of heat medium supplied to the heat exchange unit so that the amount of ice adhering to the surface of the heat exchange unit increases when the ice on the surface of the heat exchange unit becomes less than a predetermined thickness. Keeps the thickness of the ice at a predetermined thickness .

The supply unit may adjust the supply amount of the heat medium to the heat exchange unit so that ice adheres to the surface of the lower header tube.

The supply unit may adjust the supply amount of the heat medium to the heat exchange unit so that ice adheres to the connection portion between the heat transfer tube and the lower header tube.

The heat transfer tube has a tubular main body and a plurality of heat radiation fins protruding outward from the outer peripheral surface of the main body, and the supply unit has ice in a valley portion between the heat radiation fins and the heat radiation fins. The amount of heat medium supplied to the heat exchange unit may be adjusted so that

The supply unit may adjust the supply amount of the heat medium to the heat exchange unit so that the height of the ice adhering to the valley portion is 300 mm or more from the lower header tube.

As described above, according to the operation method of the open rack type heat exchange device and the open rack type heat exchange device, it is possible to suppress the wear of the sacrificial anode layer.

FIG. 1 is a diagram simply showing the configuration of an open rack heat exchanger. FIG. 2 is an end view of the line II-II of FIG. 1, illustrating the configuration of the heat exchange panel. FIG. 3 is a cross-sectional view illustrating the configuration of the connection portion between the heat transfer tube and the lower header tube.

Hereinafter, the operation method of the open rack type heat exchanger and the open rack type heat exchanger disclosed herein will be described in detail with reference to the drawings. The following description is an example.

(Configuration of open rack heat exchanger)
FIG. 1 shows the overall configuration of an open rack vaporizer (ORV) 1 as one of the open rack heat exchangers. The ORV1 is a device that heats and vaporizes liquefied natural gas (LNG), which is a low-temperature liquid, with seawater as a heat medium. FIG. 1 shows a heat exchange panel 3 constituting a main part of the ORV 1 and equipment attached thereto. The ORV 1 includes a heat exchange panel 3 in which a plurality of heat transfer tubes 2 extending in the vertical direction are arranged side by side in the horizontal direction to form a panel. Although not shown, the ORV1 is configured by arranging a plurality of heat exchange panels 3 in parallel according to the specifications.

An upper header tube 4 extending horizontally is arranged on the upper side of the heat exchange panel 3. On the lower side of the heat exchange panel 3, a lower header pipe 5 extending horizontally is arranged so as to be parallel to the upper header pipe 4. The upper end of each heat transfer tube 2 is connected to the upper header tube 4, and the lower end thereof is connected to the lower header tube 5. The heat transfer tube 2 communicates the upper header tube 4 and the lower header tube 5 with each other.

The upper header pipe 4 communicates with the upper manifold 6. The lower header pipe 5 communicates with the lower manifold 7.

A trough 8 extending in the horizontal direction is arranged adjacent to the heat transfer tube 2 on the upper part of the heat exchange panel 3. A water pipe 81 is connected to the trough 8. Seawater is supplied to the trough 8 by operating the pump 91 connected to the water distribution pipe 81. The seawater overflowing from the trough 8 flows down along the surface of the heat exchange panel 3 (that is, the heat transfer tube 2).

LNG is supplied to the lower header tube 5 via the lower manifold 7 and flows into the heat transfer tube 2. The LNG that has flowed into the heat transfer tube 2 is vaporized by exchanging heat with the seawater that flows down along the surface of the heat exchange panel 3, becomes NG, and flows out from the upper end of the heat transfer tube 2 to the upper header tube 4. The NG flowing out to the upper header pipe 4 is sent out to the outside through the upper manifold 6.

As illustrated in FIG. 2, the heat transfer tube 2 includes a circular tubular main body 21 and a plurality of heat radiation fins 22 that radiate outward from the outer peripheral surface of the main body 21 in the radial direction. There is. Each heat radiation fin 22 is orthogonal to the outer peripheral surface of the main body 21. Each heat dissipation fin 22 extends in the vertical direction. As shown in FIG. 3, the heat radiation fin 22 is not provided at the lower end of the heat transfer tube 2. Similarly, although not shown, the heat radiation fin 22 is not provided at the upper end of the heat transfer tube 2. The heat transfer tubes 2 adjacent to each other in the horizontal direction are in contact with each other.

FIG. 3 illustrates a cross section of the lower header tube 5. The lower header tube 5 is formed in a circular tubular shape in the illustrated example. The lower header tube 5 is not limited to a circular tube. The lower header tube 5 may have, for example, an elliptical cross section. The lower header tube 5 is made of, for example, an aluminum alloy.

The upper header tube 4, the lower header tube 5, and the heat transfer tube 2 constitute a heat exchange section 11 for heating a low-temperature liquid.

Although not shown, a sacrificial anode layer is formed on the surface of the heat transfer tube 2 and the surface of the lower header tube 5. The sacrificial anode layer may be formed on the surface of the heat transfer tube 2 and the surface of the lower header tube 5 by, for example, thermal spraying. Further, the sacrificial anode layer may be formed by providing a clad material on the surface of the heat transfer tube 2 and the surface of the lower header tube 5. Further, the sacrificial anode layer formed by thermal spraying and the sacrificial anode layer made of a clad material may be appropriately selected for each part of the heat exchange unit 11.

As shown in FIG. 1, the ORV1 includes a controller 92 that controls the operation of the pump 91. Although the details will be described later, the controller 92 adjusts the amount of seawater supplied to the heat exchange unit 11 by changing the rotation speed of the pump 91, for example, based on the signal from the sensor 93. A trough 8, a water pipe 81, a pump 91, and a controller 92 constitute a supply unit 12 for supplying seawater to the heat exchange unit 11.

The sensor 93 is a sensor that detects the state of ice adhering to the surface of the heat exchange unit 11. The sensor 93 may be, for example, an infrared sensor that detects the temperature distribution of the heat exchange unit 11. The controller 92 can estimate whether or not ice is attached to the surface of the heat exchange unit 11 based on the temperature of the heat exchange unit 11. Further, the sensor 93 may be an image sensor that captures an image of the surface of the heat exchange panel 3. The controller 92 may estimate whether or not ice is attached to the surface of the heat exchange unit 11 based on the image information from the sensor 93. Further, the surface of the heat exchange unit 11 is coated with a paint whose color changes according to the temperature level, and the controller 92 controls the temperature of the heat exchange unit 11 based on the image obtained by capturing the surface of the heat exchange unit 11. It is also possible to grasp the state and estimate whether or not ice is attached to the surface.

(Operation of open rack heat exchanger)
The operation of the ORV1 detects the state of ice on the surface of the heat exchange unit 11 (detection means), and supplies seawater to the heat exchange unit 11 so that the ice adheres to the surface of the heat exchange unit 11. It is characterized in that the supply amount is adjusted (control means). That is, while the ORV1 is in operation, the supply amount of LNG to the lower header pipe 5 is adjusted according to the required amount (demand amount) of natural gas. Then, the controller 92 adjusts the amount of seawater supplied to the heat exchange unit 11 through the pump 91 so that ice adheres to the surface of the heat exchange unit 11 while the ORV1 is in operation.

More specifically, the controller 92 reduces the amount of seawater supplied to the heat exchange unit 11 when the ice on the surface of the heat exchange unit 11 becomes less than a predetermined thickness. By doing so, the amount of heat input to the heat exchange unit 11 is reduced, so that ice adheres to the surface of the heat exchange unit 11, or the ice attached to the surface of the heat exchange unit 11 becomes thicker. For example, since the temperature of seawater is relatively high in summer, if the amount of seawater supplied to the heat exchange unit 11 is set to the same level as in winter, ice does not adhere to or adheres to the surface of the heat exchange unit 11. The ice becomes thin. In that case, by reducing the amount of seawater supplied to the heat exchange unit 11, ice will adhere to the surface of the heat exchange unit 11, or the ice attached to the surface of the heat exchange unit 11 will become thicker.

During the operation of ORV1, ice is present on the sacrificial anode layer by adhering ice to the surface of the heat exchange unit 11. It is prevented that the seawater flowing down the surface of the heat exchange panel 3 directly hits the sacrificial anode layer of the heat transfer tube 2 and the lower header tube 5. If ice is maintained on the surface of the heat exchange section 11 during the operation of the ORV 1, it is possible to suppress the wear of the sacrificial anode layer formed on the heat transfer tube 2 and the lower header tube 5. When the sacrificial anode layer is worn, for example, the sacrificial anode layer must be repaired by thermal spraying, but the repair frequency can be reduced by suppressing the wear of the sacrificial anode layer. The maintainability of the ORV1 can be improved.

Here, in particular, the controller 92 may adjust the amount of seawater supplied to the heat exchange unit 11 so that ice adheres to the surface of the lower header tube 5 during the operation of the ORV1. Since the seawater flowing down the surface of the heat exchange panel 3 vigorously collides with the surface of the lower header tube 5, the sacrificial anode layer formed on the surface of the lower header tube 5 is easily worn. By adjusting the amount of seawater supplied to the heat exchange unit 11 so that ice adheres to the surface of the lower header tube 5, the wear of the sacrificial anode layer can be effectively suppressed. Among the surfaces of the lower header tube 5, ice may be attached to the upper part of the lower header tube 5. This is because the sacrificial anode layer is more easily worn in the upper portion of the lower header tube 5 than in the lower portion. The "upper part" referred to here may be an upper semicircular portion (that is, θ = 180 °) in the cross section of the lower header tube 5 shown by θ in FIG.

The lower header tube 5 is a portion that does not greatly contribute to the heating of LNG. Even if ice adheres to the surface of the lower header tube 5, it has almost no effect on the performance of ORV1.

The controller 92 may also adjust the amount of seawater supplied to the heat exchange section 11 so that ice adheres to the connection portion 24 between the heat transfer tube 2 and the lower header tube 5 while the ORV 1 is in operation. As shown in FIG. 3, the connection portion 24 between the heat transfer tube 2 and the lower header tube 5 is a connection portion between the lower end portion of the heat transfer tube 2 in which the heat dissipation fin 22 is not formed and the heat transfer tube 2 and the lower header tube 5. It may be a part containing and. The seawater flowing down the heat exchange panel 3 also collects at the connection portion 24 between the heat transfer tube 2 and the lower header tube 5 and the flow is disturbed, so that the sacrificial anode layer is easily worn by the turbulent flow of seawater. By adhering ice, wear of the sacrificial anode layer provided in the connecting portion 24 can be effectively suppressed.

Further, since the connecting portion 24 also does not greatly contribute to the heating of LNG, it is acceptable for ice to adhere to the connecting portion 24.

In the ORV1 having the configuration shown in FIG. 1, since low-temperature LNG flows in the lower header tube 5, the lower part of the heat exchange section 11 has a lower temperature and the upper part of the heat exchange section 11 has a higher temperature. Therefore, ice tends to adhere to the lower part of the heat exchange portion 11, that is, the lower header tube 5 and the connection portion 24 between the heat transfer tube 2 and the lower header tube 5. The ORV1 has an advantageous configuration in preventing wear of the sacrificial anode layer due to ice adhering to the surface.

The controller 92 also provides seawater to the heat exchange section 11 so that ice adheres to the valley portion 23 (see FIG. 2) between the heat dissipation fins 22 and the heat dissipation fins 22 in the heat transfer tube 2 during the operation of the ORV1. The supply may be adjusted. In FIG. 2, the reference numerals are omitted for some of the valley portions 23.

Seawater flowing down along the surface of the heat exchange panel 3 tends to collect in the valley portion 23 between the heat radiation fins 22 and the seawater flow is disturbed, and as a result, the sacrificial anode layer is likely to be worn. By adhering ice to the valley portion 23 of the heat transfer tube 2, it is possible to prevent the sacrificial anode layer from being worn in the valley portion 23.

The controller 92 adjusts the amount of seawater supplied to the heat exchange section so that the height H of ice adhering to the valley portion 23 (see FIG. 1) is 300 mm or more from the lower header pipe 5. good. In addition, "from the lower header tube 5" may be from the connection position between the lower header tube 5 and the heat transfer tube.

Since the lower part of the heat exchange unit 11 is hit by seawater more vigorously than the upper part, the sacrificial anode layer is more likely to be worn at the lower part of the heat exchange unit 11 than at the upper part. When ice is attached to the valley portion 23 from the lower header tube 5 to a height of at least 300 mm, the wear of the sacrificial anode layer provided in the valley portion 23 can be effectively suppressed. Further, as described above, since ice is more likely to adhere to the lower portion of the heat exchange portion 11, the lower portion where the sacrificial anode layer is likely to be worn can be effectively protected by ice even in the valley portion 23.

Here, as an example, the thickness of the ice attached to the surface of the heat exchange unit 11 may be 0.5 mm or more. According to the study of the inventor of the present application, if the thickness of the ice is 0.5 mm or more, the sacrificial anode layer can be effectively protected. Further, if the thickness of the ice provided in the valley portion 23 is too thick, the surface area of the heat transfer tube 2 will be reduced, and thus the heat transfer performance will be deteriorated. The thickness of the ice provided in the valley portion 23 may be limited to a predetermined thickness or less.

The detecting means may detect the state of ice in the heat exchange unit 11 (that is, the thickness of ice or the presence or absence of ice) at a height of 300 mm from the lower header tube 5, for example. Further, the detecting means may detect the state of ice in the heat exchange section 11, for example, at the lower end portion of the heat transfer tube 2 where the heat radiation fins 22 are not formed.

The controller 92 adjusts the supply amount of seawater to the heat exchange unit 11 by controlling the operation (that is, the rotation speed) of the pump 91, and the configuration for adjusting the supply amount of seawater is this configuration. Not limited to. For example, a valve may be provided between the pump 91 and the heat exchange unit 11, and the controller 92 may adjust the amount of seawater supplied to the heat exchange unit 11 by controlling the valve. Specifically, an opening degree adjusting valve is provided between the pump 91 and the heat exchange unit 11, and the controller 92 controls the opening degree of the opening degree adjusting valve to control the opening degree of the seawater to the heat exchange unit 11. The supply may be adjusted. Further, a bypass pipe that bypasses the heat exchange unit 11 is connected between the pump 91 and the heat exchange unit 11, and the controller 92 determines the supply ratio of seawater between the heat exchange unit 11 side and the bypass side. By adjusting by control, the amount of seawater supplied to the heat exchange unit 11 may be adjusted.

Further, in the above configuration, the controller 92 adjusts the amount of seawater supplied to the heat exchange unit 11 based on the signal from the sensor 93. For example, the operator causes ice to adhere to the surface of the heat exchange unit 11. The state may be confirmed and the amount of seawater supplied to the heat exchange unit 11 may be adjusted.

1 Open rack type vaporizer (open rack type heat exchanger)
11 Heat exchange section 12 Supply section 2 Heat transfer tube (heat exchange section)
21 Main body 22 Heat dissipation fin 23 Tani part 24 Connection part 4 Upper header pipe (heat exchange part)
5 Lower header pipe (heat exchange part)
8 Trough (Supply)
81 Water pipe (supply section)
91 Pump (supply unit)
92 Controller (supply unit)

Claims (10)

A method of operating an open rack heat exchange device including a heat exchange unit for heating a low-temperature liquid or gas and a supply unit for supplying a heat medium to the heat exchange unit.
The heat exchange unit is
The lower header tube through which cold liquid or gas flows,
A plurality of heat transfer tubes whose lower ends are connected to the lower header tube and whose heat medium flows down along the surface thereof.
It has an upper header tube to which the upper end of the heat transfer tube is connected and through which a heated fluid flows in the heat transfer tube.
The heat exchange portion has a sacrificial anode layer formed on at least a part of the surface thereof, and has a sacrificial anode layer.
The step of adjusting the supply amount of the low temperature liquid to the lower header pipe and
A step of adjusting the supply amount of the heat medium to the heat exchange unit so that ice adheres to the surface of the heat exchange unit is provided .
When the ice on the surface of the heat exchange section becomes less than a predetermined thickness, the thickness of the ice is reduced by reducing the supply amount of the heat medium to the heat exchange section so that the ice adhering to the surface of the heat exchange section increases. How to operate an open rack heat exchanger that maintains the specified thickness . In the operation method of the open rack heat exchanger according to claim 1 ,
A method for operating an open rack heat exchange device that adjusts the amount of heat medium supplied to the heat exchange unit so that ice adheres to the surface of the lower header tube. In the operation method of the open rack heat exchanger according to claim 1 or 2 .
A method for operating an open rack heat exchange device that adjusts the amount of heat medium supplied to the heat exchange section so that ice adheres to the connection portion between the heat transfer tube and the lower header tube. In the operation method of the open rack heat exchanger according to any one of claims 1 to 3 , the method of operating the open rack heat exchanger.
The heat transfer tube has a tubular main body and a plurality of heat radiation fins protruding outward from the outer peripheral surface of the main body.
A method for operating an open rack heat exchange device that adjusts the amount of heat medium supplied to the heat exchange unit so that ice adheres to the valley portion between the heat radiation fins. In the operation method of the open rack heat exchanger according to claim 4 ,
A method of operating an open rack heat exchange device that adjusts the amount of heat medium supplied to the heat exchange section so that the height of ice adhering to the valley is 300 mm or more from the lower header tube. A heat exchange unit that heats a low-temperature liquid or gas,
A supply unit that supplies a heat medium to the heat exchange unit is provided.
The heat exchange unit is
The lower header tube through which cold liquid or gas flows,
A plurality of heat transfer tubes whose lower ends are connected to the lower header tube and whose heat medium flows down along the surface thereof.
It has an upper header tube to which the upper end of the heat transfer tube is connected and through which a heated fluid flows in the heat transfer tube.
The heat exchange portion has a sacrificial anode layer formed on at least a part of the surface thereof, and has a sacrificial anode layer.
The supply unit is configured to adjust the supply amount of the heat medium to the heat exchange unit so that ice adheres to the surface of the heat exchange unit .
The supply unit reduces the amount of heat medium supplied to the heat exchange unit so that the amount of ice adhering to the surface of the heat exchange unit increases when the ice on the surface of the heat exchange unit becomes less than a predetermined thickness. An open rack heat exchanger that maintains the thickness of ice at a predetermined thickness . In the open rack heat exchange device according to claim 6 ,
The supply unit is an open rack heat exchange device that adjusts the amount of heat medium supplied to the heat exchange unit so that ice adheres to the surface of the lower header tube. In the open rack heat exchange device according to claim 6 or 7 .
The supply unit is an open rack type heat exchange device that adjusts the amount of heat medium supplied to the heat exchange unit so that ice adheres to the connection portion between the heat transfer tube and the lower header tube. The open rack heat exchanger according to any one of claims 6 to 8 .
The heat transfer tube has a tubular main body and a plurality of heat radiation fins protruding outward from the outer peripheral surface of the main body.
The supply unit is an open rack type heat exchange device that adjusts the amount of heat medium supplied to the heat exchange unit so that ice adheres to the valley portion between the heat radiation fins. In the open rack heat exchanger according to claim 9 ,
The supply section adjusts the supply amount of the heat medium to the heat exchange section so that the height of the ice adhering to the valley portion is 300 mm or more from the lower header tube. Device.

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