JPH07127996A - Cleaning device for heat exchanger - Google Patents

Abstract

PURPOSE:To reduce cost of a cleaning device for a heat exchanger by a method wherein the cleaning operation is carried out under a state in which an operation of a Diesel engine having a high consumption energy is being stopped. CONSTITUTION:In the case that a cleaning operation for removing obstacles adhered to a surface of a heat transfer pipe device 6 in a heat exchanger in which the heat transfer pipe device 6 for passing cooling water W1 of a Diesel engine 1 is installed within a discharging pipe 5 passing pumped-up water W2 is required, an operation of the Diesel engine 1 is stopped, flowing of the pumped-up water W2 is shut off, circulating passage forming valves 13, 14 are closed, a changing-over valve 12 is opened to cause a heater 10 and a pump 11 to be operated, thereby a heating operation is carried out while the cooling water W1 present within the heat transfer pipe device 6 is being circulated. Then, the obstacles adhered to the surface of the heat transfer pipe device 6 are dried, and the obstacles are automatically peeled off due to a difference in expansion between the heat transfer pipe device 6 and the obstacles.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a heat exchanger cleaning device.

[0002]

2. Description of the Related Art An example of use of this type of heat exchanger is shown in FIG. That is, the diesel engine 1 has a vertical shaft pump 3 which is rotationally driven via a speed reducer 2. The vertical shaft pump 3 drains water containing sludge and the like in a water absorption tank 4 through a discharge pipe 5 and a discharge pipe. 5, a heat transfer tube unit 6 is arranged at a predetermined position, a cooling water circulation pipe 7 of the diesel engine 1 is connected to an inlet and an outlet of the heat transfer tube unit 6, and cooling is performed by a circulation pump 8 provided in the cooling water circulation pipe 7. By circulating the water, the cooling water of the diesel engine 1 passing through the heat transfer tube unit 6 and the pumping water passing through the discharge pipe 5 are indirectly heat-exchanged to cool the heated cooling water of the diesel engine 1. ing.

However, if foreign matter contained in the pumped water passing through the discharge pipe 5 adheres to the surface of a large number of heat transfer tube groups 6A constituting the heat transfer tube unit 6, the flow resistance of the pumped water and the film thermal resistance. And the like, which is a factor that significantly reduces the heat exchange efficiency. Therefore, a cleaning operation is required to remove foreign matter adhering to the surface of the heat transfer tube group 6A or the like regularly or as needed. However, in the conventional cleaning method, the heat exchanger must be disassembled, that is, the heat transfer tube unit 6 must be disassembled.
There was a drawback that cleaning work was troublesome. Therefore, the applicant of the present invention has provided a cleaning method capable of cleaning the heat exchanger (heat transfer tube unit 6) without disassembling it (Japanese Patent Publication No. 2-44000).

According to this cleaning method, cleaning can be performed without disassembling the heat exchanger, so that the cleaning workability can be greatly improved. However, since the large number of heat transfer tube groups 6A are heated by the heated cooling water of the diesel engine 1, the foreign substances adhering to the surface of the heat transfer tube groups 6A are dried to form the heat transfer tube groups 6A. The diesel engine 1 which consumes a large amount of energy must be continuously operated until it is naturally peeled off due to the difference in thermal expansion. Therefore, the cost required for cleaning is high.

[0005]

The problem to be solved is that the cooling water (first fluid) heated by the heat transfer tube unit while the diesel engine (driving source) which consumes a large amount of energy is continuously operated. Since it must be passed through, the cost of cleaning is high.

[0006]

According to the present invention, a heat transfer tube unit that allows a first fluid to pass therethrough is disposed in a second fluid passage that allows a second fluid to pass therethrough. In a cleaning device for a heat exchanger in which a second fluid is heat-exchanged, a communication pipe that connects an inlet upstream position and an outlet downstream position of the heat transfer pipe unit is provided, and the communication pipe has a heating means, a circulation means, and the communication pipe. In addition to providing a switching valve for controlling the fluid circulation / stop of the above, a circulation path forming valve is provided at each of the upstream side of the inlet upstream position and the downstream side of the outlet downstream position. The purpose of reducing the cost was achieved by cleaning with the drive source of large energy consumption stopped.

[0007]

According to the present invention, the operation of the drive source is stopped and the second
Of the fluid in the second fluid passage is closed, the circulation passage forming valve is closed, and the switching valve is opened to operate the heating means and the circulation means to circulate the first fluid in the heat transfer tube unit. While heating, the foreign matter adhering to the surface of the heat transfer tube unit is dried, and the foreign matter can be naturally peeled off due to the difference in thermal expansion between the heat transfer tube unit and the foreign matter.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram showing an embodiment of the present invention.
It should be noted that the same or corresponding parts as those in the conventional example of FIG. In FIG. 1, a heat transfer tube unit 6 for passing heated cooling water W1 of a diesel engine 1 is arranged at a predetermined position in a discharge pipe 5 for passing pumped water W2 sucked from a water absorption tank 4 by a vertical shaft pump 3. . The heat transfer tube unit 6 is, as shown in FIG.
It is equipped with a large number of heat transfer tube groups 6A and a pair of left and right headers 6B1 and 6B2 bridging the heat transfer tube groups 6A. The cooling water circulation pipe 7 is connected.

On the other hand, in the vicinity of the inlet of the upstream header 6B1 in the cooling water circulation pipe 7, that is, the upstream header 6B.
1 upstream position P1 and the outlet of the downstream header-6B2 in the cooling water circulation pipe 7, that is, the downstream header-6.
A communication pipe 9 for communicating the downstream position P2 of B2 is provided,
A heater 10, a pump 11, and a switching valve 1 are connected to the communication pipe 9.
2 is installed. In addition, circulation path forming valves 13 and 14 are provided on the upstream side of the upstream position P1 and the downstream side of the downstream position P2 in the cooling water circulation pipe 7, respectively.

With such a structure, the vertical shaft pump 3 is rotationally driven by the operation of the diesel engine 1 via the speed reducer 2, and the water containing sludge in the water absorption tank 4 is drained through the discharge pipe 5. , The switching valve 12 is closed, the circulation passage forming valves 13 and 14 are opened, and the heater 10 and the pump 1
In the state where the operation of No. 1 is stopped, the cooling water W1 of the diesel engine 1 is circulated by the operation of the circulation pump 8 so that the cooling water of the diesel engine 1 passing through the heat transfer tube unit 6 and the pumping water W2 passing through the discharge pipe 5 are provided. Indirect heat exchange can be performed to cool the heated cooling water of the diesel engine 1.

On the other hand, when a large amount of foreign matter contained in the pumped water W2 adheres to the surface of a large number of heat transfer tube groups 6A constituting the heat transfer tube unit 6 over time and cleaning is required to remove the foreign matter. By stopping the operation of the diesel engine 1 and stopping the vertical shaft pump 3, the flow of the pumped water W2 in the discharge pipe 5 is shut off, the circulation passage forming valves 13 and 14 are closed, and the switching valve 12 is opened to open the heater 10 and the pump 11. Is operated to heat the circulating cooling water W1 in the heat transfer tube unit 6 to dry foreign matter adhering to the surface of a large number of heat transfer tube groups 6A and the like. 6
Due to the difference in thermal expansion between A and the foreign matter, the foreign matter can be naturally peeled off and removed from the surface of the large number of heat transfer tube groups 6A and the like.

As described above, since it is possible to perform cleaning while the diesel engine 1 which consumes a large amount of energy is stopped, compared with the conventional cleaning method in which cleaning is performed while the diesel engine 1 is continuously operated. Therefore, the cost can be reduced.

FIG. 3 shows a modification of the present invention, in which the same or corresponding parts as those of the embodiment of FIG. In FIG. 2, the upstream header-6
The intake / exhaust pipe 16 provided with the atmosphere opening valve 15 at B1 is continued, and the heater 10, the blower 11, and the switching valve 1 are provided at the communication pipe 9.
2 and 12, a drain pipe 18 having a drain valve 17 is branched from a connection position P1 between the communication pipe 9 and the cooling water circulation pipe 7 and the circulation passage forming valve 13.

Therefore, when cleaning for removing foreign matters is required, the operation of the diesel engine 1 is stopped and the vertical shaft pump 3 is stopped to shut off the flow of the pumped water W2 in the discharge pipe 5 and to form the circulation path forming valve. After closing 13 and 14, the atmosphere release valve 15 and the drain valve 17 are opened to discharge the warmed cooling water W1 in the heat transfer tube unit 6 from the drain tube 18 to the outside and to inject air from the intake / exhaust tube 16. It is introduced and the inside of the heat transfer tube unit 6 is replaced with air, and the atmosphere release valve 1
5 and the drain valve 17 are closed. After that, switching valve 1
2 and 12 are opened to operate the heater 10 and the blower 11 to heat the air E in the heat transfer tube unit 6 while circulating it, and to dry the foreign matter adhering to the surface of the large number of heat transfer tube groups 6A and the like. The heat transfer tube group 6A and the foreign matter are removed by a large difference in thermal expansion between the heat transfer tube group 6A and the foreign matter, and a large number of heat transfer tube groups 6
It can be removed from the surface such as A. In other words, since it is designed to heat air, which has a smaller specific heat than water,
The energy for heating can be suppressed smaller than when circulating the cooling water W1.

[0015]

As described above, according to the present invention, the operation of the drive source is stopped to shut off the flow of the second fluid in the second fluid passage, the circulation passage forming valve is closed, and the switching valve is opened. By operating the heating means and the circulation means by heating, the first fluid in the heat transfer tube unit is circulated and heated, and the foreign matter adhering to the surface of the heat transfer tube unit is dried, and the heat transfer tube unit and the foreign matter are dried. Since the foreign material can be naturally peeled off due to the difference in thermal expansion between and, the cost can be reduced as compared with the conventional cleaning method.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part.

FIG. 3 is an enlarged view showing a modified example of the present invention.

FIG. 4 is a system diagram of a conventional example.

[Explanation of symbols]

 5 Discharge pipe (second fluid passage) 6 Heat transfer pipe unit 9 Communication pipe 10 Heater (heating means) 11 Pump or blower (circulation means) 12 Switching valve 13 Circulation passage formation valve 14 Circulation passage formation valve E Air (first Fluid) P1 Heat transfer tube unit inlet upstream position P2 Heat transfer tube unit outlet downstream position W1 Cooling water (first fluid) W2 Pumping water (second fluid)

Claims (1)

[Claims] 1. A heat transfer tube unit for passing a first fluid is a second
In a cleaning device for a heat exchanger, which is arranged in a second fluid passage through which the fluid flows, and in which heat is exchanged between the first fluid and the second fluid via the heat transfer tube unit, an inlet upstream position of the heat transfer tube unit. And a communication pipe that connects the downstream position of the outlet with
A heating unit, a circulation unit, and a switching valve for switching and controlling fluid circulation / stop of the communication pipe are provided in the communication pipe, and circulation is performed on each of the upstream side of the inlet upstream position and the downstream side of the outlet downstream position. A heat exchanger cleaning device characterized in that a passage forming valve is provided.