JP3594804B2 - Ozone circulation cleaning equipment for plate heat exchanger - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ozone circulation cleaning device for a plate heat exchanger, and more particularly, to a plate heat exchanger suitable for reliably suppressing the growth and adhesion of microorganisms to the heat transfer surface of a heat exchange plate. The present invention relates to an ozone circulation cleaning device.
[0002]
[Prior art]
A conventional ozone circulation cleaning device for a plate heat exchanger is configured as shown in FIG. That is, the heat exchange unit 2 composed of an aggregate of the plurality of heat exchange plates 1 and 1 is inserted into the heat exchanger body 3 and the heat medium F is introduced into each heat exchange plate 1 and 1 from the inlet 2A of the heat exchange unit 2. The heat medium F is led out of the heat exchange unit 2 from the outlet 2B, and the water W such as sewage, river water, or seawater passes through the heat exchanger main body 3 and passes through the outlet 2B. Indirect heat exchange is performed between the water W and the heat medium F passing through each heat exchange plate 1, 1 via the heat transfer surface of each heat exchange plate 1, 1.
[0003]
A water supply pipe 4 is connected to an inlet 3A of the heat exchanger body 3, a drain pipe 5 is connected to an outlet 3B, a water cutoff valve 6 is interposed in the water supply pipe 4, and a water cutoff valve is connected to the drain pipe 5. 7 are interposed. The position of the water supply pipe 4 immediately downstream of the water cutoff valve 6 and the position of the drainage pipe 5 immediately upstream of the water cutoff valve 7 are in communication with each other via a communication pipe 8. The communication pipe 8 has a first circulation valve 9 and a second circulation valve 10 composed of a check valve that allows only the flow from the communication pipe 8 to the water supply pipe 4 and blocks the flow from the water supply pipe 4 to the communication pipe 8. Is interposed. Therefore, by closing the water cutoff valves 6 and 7 and opening the first circulation valve 9, the circulation loop 11 including the water supply pipe 4, the inside of the heat exchanger body 3, the drainage pipe 5, and the communication pipe 8 is formed. Can be configured. A circulation pump 12 is provided in the communication pipe 8.
[0004]
On the other hand, the ozone generation source 14 communicates with the inside of the communication pipe 8 via the ozone supply pipe 15 and the ozone injecting ejector 13. Therefore, by operating the circulation pump 12 and the ozone generation source 14 in the state where the circulation loop 11 is formed, ozone is injected (supplied) into the circulation loop 11 and the ozone-dissolved water can be circulated.
[0005]
On the other hand, by injecting ozone, the apparent volume in the circulation loop 11 increases, so that the discharge pipe 18 in which the expansion tank 16 and the ozone decomposer 17 filled with activated carbon are interposed in series from the communication pipe 8. The expansion tank 16 absorbs the increased volume, and the excess gas is guided to the ozone decomposer 17 from the top of the expansion tank 16 and discharged. With such a configuration, the circulation loop 11 is opened to the atmosphere.
[0006]
By the way, the water cutoff valves 6 and 7 are opened, the first circulation valve 9 is closed, and the water W such as sewage, river water, or seawater passes inside the heat exchanger body 3. When W and the heat medium F passing through the heat exchange plates 1 and 1 are indirectly heat-exchanged via the heat transfer surfaces of the heat exchange plates 1 and 1, the sewage, river water, seawater, or the like over time. Microorganisms contained in the water W may adhere to the surfaces of the heat exchange plates 1 and 1, that is, heat transfer surfaces, and proliferate to produce microbial dirt called slime. And the heat exchange efficiency decreases.
[0007]
Then, the water shutoff valves 6 and 7 are closed, the first circulation valve 9 is opened, and the circulation pump 12 and the ozone generation source 14 are operated, so that ozone is injected into the circulation loop 11 and ozone is injected. Ozone treatment for circulating dissolved water removes microbial dirt called slime and suppresses the attachment and growth of microorganisms on the heat transfer surface.
[0008]
According to the ozone circulation cleaning device of the plate type heat exchanger, it is relatively simple and requires less labor than disassembly cleaning, stationary cleaning using a chemical called CIP, or stationary cleaning using warm water. Microbial stains called slime can be removed, and adhesion and growth of microorganisms on the heat transfer surface can be suppressed.
[0009]
[Problems to be solved by the invention]
In this ozone circulation cleaning device, the water cutoff valves 6 and 7 are opened, the first circulation valve 9 is closed, and water W such as sewage, river water, or seawater passes inside the heat exchanger body 3. In the state where the heat exchange is performed, a pressure corresponding to the use condition is applied in the heat exchanger main body 3, and the heat exchanger main body 3 is expanded with a slight internal pressure. When performing ozone circulation cleaning, first, the water cutoff valves 6 and 7 are closed, and then the first circulation valve 9 is opened to form a circulation loop 11, but the first circulation valve 9 is opened. At the moment, the water equivalent to the expansion of the heat exchanger body 3 overflows through the expansion tank 16 and the ozone decomposer 17, and the function of the expansion tank 16 is lost due to its fullness and the ozone decomposing function is immersed in the ozone decomposer 17. There is a risk of causing the loss.
[0010]
Therefore, the present invention prevents water corresponding to the expanded volume of the heat exchanger body from overflowing through the expansion tank and the ozone decomposer at the time of forming the circulation loop, so that the function of the expansion tank is lost. The ozone of the plate type heat exchanger which can avoid loss of the function of the ozone decomposer and can equalize the flow of the circulating fluid into the heat exchanger body at the time of forming the circulation loop to improve the cleaning ability. It is an object to provide a circulation cleaning device.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, in the ozone circulation cleaning apparatus for a plate heat exchanger according to the present invention, a heat exchange unit including an aggregate of a plurality of heat exchange plates is inserted into a heat exchanger body, and the heat exchange A heat medium is sequentially introduced and passed into each heat exchange plate from the inlet of the unit, and the heat medium is led out of the heat exchange unit from the outlet, and water is passed inside the heat exchanger body. A water supply pipe connected to an inlet of the heat exchanger main body, wherein the passing water and a heat medium passing through each of the heat exchange plates are indirectly heat-exchanged through a heat transfer surface of each heat exchange plate; A drain pipe connected to the outlet of the vessel body, a water cutoff valve interposed in each of the water supply pipe and the drain pipe, the water supply pipe on the downstream side of the water cutoff valve, and the drainage on the upstream side of the water cutoff valve. A communication pipe that connects the pipes to each other The water supply pipe, the inside of the heat exchanger body, the drain pipe and the communication pipe are provided by closing the respective water cutoff valves and opening the circulation valve interposed in the communication pipe. A circulation loop is formed, a circulation pump is operated, and ozone generated by an ozone generation source is supplied to the circulation loop to circulate ozone-dissolved water. An expansion tank and an ozone decomposer are connected in series to the circulation loop. In the plate-type heat exchanger ozone circulating cleaning device provided with a branching discharge pipe interposed in the main body, the volume of the main body expanded by the internal pressure of the heat exchanger main body when each of the water cutoff valves is closed. In addition to providing a relief valve for releasing water, the outlet of the communication pipe is eccentrically connected to the water supply pipe so that the fluid flowing into the water supply pipe from the communication pipe generates a swirling flow around the axis of the water supply pipe. Characterized by comprising It is.
[0012]
According to the present invention, after closing the water cutoff valve, first, the relief valve is opened to release the volume of water in which the main body has expanded due to the internal pressure of the heat exchanger main body, and then the release valve is opened. The expansion is performed by closing and opening a circulation valve to form a circulation loop, operating a circulation pump, and supplying ozone generated by an ozone generation source in a circulation loop to circulate ozone-dissolved water. It is possible to prevent the water corresponding to the volume that has been flowing out from flowing through the expansion tank and the ozone decomposer, thereby preventing the loss of the function of the expansion tank and the function of the ozone decomposer. Further, when the circulation loop is formed, a swirling flow around the axis is generated in the water supply pipe, and the swirling flow is guided to the heat exchanger main body, so that the inflow of the circulating fluid into the heat exchanger main body is equalized and washed. The ability can be improved.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing an embodiment of the present invention, and FIG. 2 is an enlarged sectional view showing a relationship between a communication pipe and a water supply pipe. The same or corresponding parts as those of the conventional example shown in FIG. 1 and 3, an expansion relief pipe 19 is provided at a position immediately upstream of the first circulation valve 9 in the communication pipe 8, and a relief valve 20 is provided in the expansion relief pipe 19. Further, the outlet of the communication pipe 8 is eccentrically connected to the water supply pipe 4 so as to generate a swirling flow S around the axis of the water supply pipe 4 in the fluid flowing into the water supply pipe 4 from the communication pipe 8.
[0014]
With such a configuration, the water cutoff valves 6 and 7 are opened, the first circulation valve 9 is closed, and water W such as sewage, river water, or seawater is discharged inside the heat exchanger body 3. The passage allows the indirect heat exchange between the passing water W and the heat medium F passing through the heat exchange plates 1, 1 via the heat transfer surfaces of the heat exchange plates 1, 1.
[0015]
On the other hand, after closing the water cutoff valves 6 and 7 regularly or periodically, first, the relief valve 20 is opened to discharge water of a volume that has been expanded by the internal pressure of the heat exchanger main body 3. A circulation loop 11 is formed by releasing the expansion relief pipe 19, then closing the relief valve 20 and opening the first circulation valve 9 to operate the circulation pump 12. Then, the ozone generated by the ozone generating source 14 is supplied to the circulation loop 11 to circulate the ozone-dissolved water, so that the water corresponding to the expanded volume passes through the expansion tank 16 and the ozone decomposer 17. Ozone circulating washing treatment for circulating ozone-dissolved water in a state where loss of function of the expansion tank 16 and loss of function of the ozone decomposer 17 is prevented by preventing overflow and overflow is performed, and microbial contamination called slime is performed. , And adhesion and growth of microorganisms on the heat transfer surface can be suppressed.
[0016]
When the circulation loop 11 is formed, a swirling flow S around the axis is generated in the water supply pipe 4, and the swirling flow S is guided to the heat exchanger main body 3. And the cleaning ability can be improved by equalizing the inflow of water.
[0017]
In the above-described embodiment, an expansion relief pipe 19 is provided at a position immediately upstream of the first circulation valve 9 in the communication pipe 8, and the expansion relief pipe 19 is provided with a relief valve 20 interposed therebetween. However, as shown by an imaginary line in FIG. 1, an expansion relief pipe 19 may be branched from the water cutoff valve 7 in the drain pipe 5, and a relief valve 20 may be provided in the expansion relief pipe 19.
[0018]
【The invention's effect】
As described above, after closing the water cutoff valve, the present invention first opens the relief valve to release water of the volume in which the main body has expanded due to the internal pressure of the heat exchanger main body, A circulation loop can be formed by closing the relief valve and opening the circulation valve, so that the water corresponding to the expanded volume of the heat exchanger body when the circulation loop is formed passes through the expansion tank and the ozone decomposer. By circulating the ozone-dissolved water in a state where it is prevented from overflowing and avoiding the loss of function of the expansion tank and the function of the ozone decomposer, microbial dirt called slime is removed and heat transfer is performed. Adhesion and growth of microorganisms on the surface can be suppressed. Further, when the circulation loop is formed, a swirling flow around the axis is generated in the water supply pipe to guide the swirling flow to the heat exchanger main body, so that the inflow of the circulating fluid into the heat exchanger main body is equalized and the cleaning capacity is increased. Can be improved.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an embodiment of the present invention.
FIG. 2 is an enlarged sectional view showing a relationship between a communication pipe and a water supply pipe.
FIG. 3 is a configuration diagram of a conventional example.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 heat exchange plate 2 heat exchange unit 2A heat exchange unit inlet 2B heat exchange unit outlet 3 heat exchanger body 3A heat exchanger body inlet 3B heat exchanger body outlet 4 water supply pipe 5 drain pipe 6 water cutoff valve 7 water cutoff valve 8 communication pipe 9 first circulation valve 10 check valve (second circulation valve)
DESCRIPTION OF SYMBOLS 11 Circulation loop 12 Circulation pump 14 Ozone generation source 15 Ozone supply pipe 16 Expansion tank 17 Ozone decomposer 20 Relief valve F Heat medium W Water S Swirling flow

Claims (1)

A heat exchange unit composed of an aggregate of a plurality of heat exchange plates is inserted into the heat exchanger body, a heat medium is sequentially introduced and passed through each heat exchange plate from an inlet of the heat exchange unit, and heat exchange is performed from an outlet. The heat medium is led out of the unit, water is passed inside the heat exchanger body, and the passing water and the heat medium passing through each heat exchange plate are connected to the heat transfer surface of each heat exchange plate. Is indirectly heat-exchanged via a water supply pipe connected to an inlet of the heat exchanger main body, a drain pipe connected to an outlet of the heat exchanger main body, and provided in each of the water supply pipe and the drain pipe. A water cutoff valve, a communication pipe that connects the water supply pipe on the downstream side of the water cutoff valve and the drainage pipe on the upstream side of the water cutoff valve with each other, and closes each of the water cutoff valves, And by opening the circulation valve interposed in the communication pipe The water supply pipe, the inside of the heat exchanger body, forming a circulation loop consisting of the drainage pipe and the communication pipe, operating a circulation pump, and supplying ozone generated by an ozone generation source to the circulation loop, In the ozone circulation cleaning device of the plate type heat exchanger, the ozone-dissolved water is circulated, and a discharge pipe having an expansion tank and an ozone decomposer arranged in series is branched and provided in the circulation loop. When the shut-off valve is closed, a relief valve is provided to release the volume of water expanded by the internal pressure of the heat exchanger main body due to the internal pressure of the heat exchanger main body. An ozone circulation cleaning apparatus for a plate-type heat exchanger, wherein a swirling flow around an axis of a water supply pipe is generated in a fluid flowing into the water supply pipe.

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