WO2010029786A1 - Heat exchanger device operating method and heat exchanger device - Google Patents

Abstract

The heat exchanger device operating method can prevent the adherence of a scale to a heated liquid flow path, while keeping the amount of heat transferred to the heated liquid constant. With the heat exchanger device operating method, after the heated liquid is heated by heat exchange with a thermal medium and flows out the heated liquid flow path, part of the heated liquid flows into a heated liquid circulation pipeline, pulsations are produced in the inflowing part of the heated liquid by the intermittent driving of a circulation pump, and the heated liquid in which pulsations have been produced again flows unchanged into the heated liquid flow path.

Description

Operation method of heat exchanger apparatus and heat exchanger apparatus

The present invention relates to a method of operating a heat exchanger apparatus and a heat exchanger apparatus having a function of preventing scale from adhering to a heated liquid passage through which heated liquid flows and exchanges heat with an external heat medium. It is about.

Water heaters that supply hot water to the bathroom or kitchen are roughly divided into electric water heaters, gas water heaters, and oil water heaters, and all have parts called heat exchangers for transferring heat to water. Among electric water heaters, in particular, heat pump heat exchange type electric water heaters (heat pump water heaters) are attracting attention from the viewpoint of energy saving and carbon dioxide reduction as a measure against global warming.
The principle is that the heat of the atmosphere is transferred to a heat medium, and hot water is boiled with that heat. Specifically, the heat generated when the gas is compressed is transferred to water via a heat exchanger, and the temperature of the heat medium is returned to the atmospheric temperature again by the cold air when the gas is expanded (cooling cycle). Is due to. Theoretically, it is not possible to extract more heat energy than the input energy, but the heat pump water heater uses the heat of the atmosphere, so it can use more heat energy than the energy required for operation.

In order for the heat exchanger to transfer heat to the water, it is very important to keep the heat transfer surface clean at all times. When the partition wall is soiled, the effective heat transfer area is reduced and the heat transfer performance is deteriorated. Further accumulation of dirt causes blockage of the flow path in the worst case.
In particular, in a region where the hardness component (calcium ion or magnesium ion) in water is high, there is a problem that carbonate crystals called scales are deposited by heating and easily adhere to the heat exchanger.

As a conventional heat exchanger device, for example, Patent Document 1 discloses a heating means, a heat exchange path 29 provided so as to be able to exchange heat with the heating means, and a pump 28 interposed in the heat exchange path 29. And the pump 28 is driven at a rotational speed higher than the rotational speed at the time of steady operation for a certain period of time, thereby temporarily increasing the speed of hot water flowing through the heat exchange path 29. A descaling method for removing scale is described.

Other Patent Document 2 includes a circulation pump 3 that circulates the heat exchange liquid and a controller 10 that controls at least the operation of the circulation pump 3, and fully drives the circulation pump 3 at regular time intervals. A hot water heater that removes the scale in the heat exchanger 2 is described.

JP 2001-263793 A JP 2005-308235 A

However, in Patent Document 1, the purpose is not to pulsate the speed of the hot water flowing in the heat exchange path 29, but, for example, the scale removal operation is performed for a certain time after the entire amount of hot water in the hot water tank is boiled. .
In addition, the above-mentioned Patent Document 2 is not intended to pulsate the speed of the heat exchange liquid, but when the integrated value of the operation time used to heat the heat exchange liquid reaches a predetermined value, The circulating means of the exchange liquid was fully driven.

These operation operations are to recirculate hot water passing through the hot water storage tank from the inlet of the heat exchange path and increase the flow rate temporarily. In order to distribute the heat exchange path with a narrow diameter or width, There was a problem of requiring a great deal of power.
In addition, since hot water after heat dissipation has circulated in the hot water storage tank and other piping is circulated, there is a problem that an extra amount of heat is required to maintain the hot water supply temperature constant.
Further, if this operation is repeated at an extremely short interval, an action close to pulsation can be given to the flow rate of hot water, but those described in Patent Documents 1 and 2 have the following problems. there were. That is,
Since hot water passing through the hot water storage tank is recirculated from the inlet of the heat exchange path, when hot water passes through the heat exchange path with a narrow diameter or width, it receives the frictional resistance generated between the partition walls and generates the largest scale. However, there is a problem that the change in the flow velocity becomes dull near the outlet of the heat exchange path where the temperature of the heat exchange path partition wall and the hot water temperature are the highest, and a sufficient scale adhesion prevention effect or scale removal effect cannot be obtained. .

An object of the present invention is to solve the above-described problems, and it is easy for a scale to adhere to a heated liquid passage through which the heated liquid flows and exchanges heat with an external heat medium. It is an object of the present invention to provide a heat exchanger apparatus operating method and a heat exchanger apparatus that can be prevented with a simple configuration.

The operation method of the heat exchanger apparatus according to the present invention includes a heat exchanger having a heated liquid channel through which a heated liquid flows and exchanges heat with an external heat medium, and is connected to an inlet of the heated liquid channel The heated liquid inlet pipe, the heated liquid outlet pipe connected to the outlet of the heated liquid flow path through which the heated liquid is discharged, and a tip portion branched from the heated liquid outlet pipe The heated liquid circulation pipe connected in the middle of the heated liquid flow path and the heated liquid circulation pipe provided between the heated liquid flow path and the heated liquid circulation pipe An operation method of a heat exchanger apparatus comprising a circulation pump for circulation, wherein the heated liquid is heated by heat exchange with the heat medium and flows out of the heated liquid flow path, and then the heated liquid A part flows into the heated liquid circulation pipe, and the heated liquid flowing in Pulsation by the intermittent driving operation of the circulation pump occurs, the heated fluid pulsation occurs, it again enters the the heated liquid flow path.

A heat exchanger apparatus according to the present invention includes a heat exchanger having a heated liquid passage through which a liquid to be heated flows and exchanges heat with an external heat medium, and a target connected to an inlet of the heated liquid passage. A heated liquid inlet pipe, a heated liquid outlet pipe connected to an outlet of the heated liquid flow path through which the heated liquid is discharged, a branch from the heated liquid outlet pipe, and a distal end portion of the heated liquid outlet pipe A heated liquid circulation pipe connected in the middle of the heated liquid flow path, and a circulation provided in the heated liquid circulation pipe for circulating the heated liquid between the heated liquid flow path and the heated liquid circulation pipe A pump and a controller for controlling the operation of the circulation pump are provided, and the controller is configured to intermittently operate the circulation pump.

According to the operation method of the heat exchanger apparatus and the heat exchanger apparatus according to the present invention, the liquid to be heated is circulated between the downstream side in the middle of the liquid path to be heated and the liquid circulation pipe to be heated in an intermittent operation. By doing so, it is possible to cause a pressure change of the liquid to be heated in the liquid flow path to be heated and to prevent the scale from adhering to the liquid flow path to be heated.

It is a schematic block diagram of the heat exchanger apparatus in Embodiment 1 of this invention. It is a figure which shows the scale adhesion prevention effect when using the heat exchanger apparatus of FIG. It is a figure which shows the scale adhesion prevention effect when using the heat exchanger apparatus of FIG. It is a figure which shows the scale adhesion prevention effect when using the heat exchanger apparatus of FIG. It is a whole perspective view of the heat exchanger apparatus in Embodiment 2 of this invention. It is a top view which shows the low temperature side heat exchanger plate of FIG. It is a top view which shows the high temperature side heat exchanger plate of FIG. It is a top view which shows the end plate of FIG. It is a figure which shows the cross section which shows the heat exchanger plate module of FIG. 5, and the flow of a to-be-heated liquid. It is a figure which shows the cross section which shows the heat exchanger plate module of FIG. 5, and the flow of a heat carrier. It is sectional drawing which shows the heat exchanger plate module of the heat exchanger apparatus in Embodiment 3 of this invention. It is a top view which shows the end plate of FIG. It is a top view which shows the low temperature side heat exchanger plate of FIG. It is a top view which shows the high temperature side heat exchanger plate of FIG. It is a figure which shows operation | movement of the control valve of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or equivalent members and parts will be described with the same reference numerals.
Embodiment 1
1 is a schematic configuration diagram showing a hot water supply apparatus including a heat exchanger apparatus 100 according to Embodiment 1 of the present invention.
This hot water supply apparatus includes an air-heat medium heat exchanger 91 for transferring the heat of the outside air to a heat medium that is, for example, carbon dioxide refrigerant, a compressor 92 for compressing the heat medium, A heat medium-water heat exchanger 100b that heats the water to be heated by heat and an expansion valve 93 for cooling the heat medium are provided.
The heat medium-water heat exchanger 100 b in the heat exchanger apparatus 100 is connected to the air-heat medium heat exchanger 91 via the heat medium inlet pipe 99. A compressor 92 is attached to the heat medium inlet pipe 99.
The heat medium-water heat exchanger 100 b is connected to the air-heat medium heat exchanger 91 via the heat medium outlet pipe 55. An expansion valve 93 is attached to the heat medium outlet pipe 55.
Inside the heat medium-water heat exchanger 100b, a heated liquid channel 100a that is a heat transfer tube heated while water passes is provided.
A heated liquid inlet pipe 9 through which water flows into the heat medium-water heat exchanger 100b is connected to one end of the heated liquid channel 100a. A heated liquid outlet pipe 5 for discharging heated water to the outside of the heat medium-water heat exchanger 100b is connected to the other end of the heated liquid channel 100a.

A heated liquid circulation pipe 6 is branched from the heated liquid outlet pipe 5. The tip of the heated liquid circulation pipe 6 is connected in the middle of the heated liquid flow path 100a. A circulation pump 7 is attached to the heated liquid circulation pipe 6. By driving the circulation pump 7, water to be heated circulates in the order of the heated liquid flow path 100a, the heated liquid outlet pipe 5, the heated liquid circulation pipe 6, and the heated liquid flow path 100a.
The circulation pump 7 is connected to a controller 8 that controls driving of the circulation pump 7 via a signal line 8a.

In FIG. 1, in the heat medium-water heat exchanger 100b, the relationship between the heat medium and water is countercurrent, but it may be parallel flow.
Further, the heated liquid outlet pipe 5 and the heated liquid inlet pipe 9 are connected to a hot water supply tank (not shown), and the hot water, which is the heated heated liquid stored in the hot water tank, is reheated to the heating medium-water heat. You may make it send to the exchanger 100b and reheat a to-be-heated liquid.

Next, operation | movement of the heat exchanger apparatus 100 of the said structure is demonstrated.
First, the heat medium that has absorbed the heat of the outside air by the air-heat medium heat exchanger 91 is once evaporated and compressed by the compressor 92 to become a high-temperature and high-pressure gas through the heat medium inlet pipe 99. It is sent to the water heat exchanger 100b.
On the other hand, the water sent to the heating medium-water heat exchanger 100b through the heated liquid inlet pipe 9 is heated while passing through the heated liquid channel 100a provided in the heating medium-water heat exchanger 100b. It is heated by receiving heat from the medium and flows out from the heated liquid outlet pipe 5.
The heat medium deprived of heat in the heat medium-water heat exchanger 100b is sent to the expansion valve 93 through the heat medium outlet pipe 55, where it is decompressed and becomes liquid again. The liquid heat medium is returned to the air-heat medium heat exchanger 91 to absorb the heat of the outside air and repeat the above cooling cycle.

A part of the water flowing out from the heated liquid outlet pipe 5 is returned to the heated liquid flow path 100a in the heat medium-water heat exchanger 100b through the heated liquid circulation pipe 6 by driving the circulation pump 7. At this time, the controller 8 performs control so that the circulation pump 7 is repeatedly turned on and off at regular intervals through the signal line 8a.
As a result, the liquid is branched from the heated liquid outlet pipe 5 from the vicinity of the outlet of the heated liquid flow path 100a, that is, from the point where the warm water from the upstream of the heated liquid flow path 100a and the warm water from the heated liquid circulation pipe 6 merge. In the region up to the end of the heated liquid circulation pipe 6, the flow rate of the hot water that is the heated liquid is intermittently increased, and pulsation occurs in this region.

As described above, water that is the liquid to be heated is heated by receiving heat from the heat medium while passing through the liquid channel 100a to be heated, so that the water temperature is the highest near the outlet of the liquid channel 100a to be heated. It can be said that the scale rises and the scale is easily attached.
Therefore, generating pulsation in this region effectively prevents the occurrence of scale adhesion.
In this way, the position where the heated liquid circulation pipe 6 is connected to the heated liquid flow path 100a is located on the outlet side (downstream side) from the center of the heated liquid flow path 100a, thereby efficiently generating scale adhesion. Can be prevented.

At this time, the region where the water to be heated pulsates is only in the vicinity of the outlet of the heated liquid channel 100a, so that the pressure loss is higher than when returning water further upstream, for example, to the heated liquid inlet pipe 9. small. That is, it is possible to reliably pulsate the water without slowing the speed change, and to more reliably prevent scale adhesion.
Further, the capacity or power of the circulation pump 7 can be small.
Further, water circulates in a part of the heated liquid channel 100 a, but the flow rate of water flowing into the heated liquid channel 100 a through the heated liquid inlet pipe 9 and the heated liquid outlet pipe 5 The flow rate of the heated hot water flowing out from the heating liquid channel 100a can be always kept constant. That is, the hot water supply amount and the hot water supply temperature can be kept constant while preventing scale adhesion.

Next, a specific example of the scale adhesion preventing effect of the heated liquid channel 100a in the heat exchanger apparatus 100 according to Embodiment 1 of the present invention will be described.
FIG. 2 shows a high hardness water (hardness 270 mg-CaCO ₃ / l) on a copper straight pipe having a length of 25 cm, an outer diameter of 8 mm, and an inner diameter of 6 mm simulated by the inventor of the heat medium-water heat exchanger 100b. It is the experimental result which analyzed the amount of scales adhering to the copper straight pipe inner surface when it was distribute | circulated for 200 hours. The attached scale was extracted with 1 mol / l dilute hydrochloric acid, and then the amount of calcium ions was measured using a high performance liquid chromatography analyzer.

In FIG. 2, the results of three steady flow experiments (0.5 m / s, 0.75 m / s, and 1.0 m / s) using the flow rate of high hardness water as a parameter and the results of an experiment that gave pulsation Are shown together.
In the pulsation experiment, a flow rate of 0.5 m / s was continued for 10 seconds, and then an increment of 0.25 m / s was further applied for 10 seconds. That is, a flow rate of 0.5 m / s and 0.75 m / s (= 0.5 + 0.25 m / s) were alternately repeated every 10 seconds.
As a result, as shown in FIG. 2, scale adhesion was observed when the flow velocity was 0.5 m / s, 0.75 m / s, and 1.0 m / s, but the pulsation was “0.5 + 0.25 m / s”. In the case of, no scale adhesion was observed even 200 hours after the start of the experiment.

It is clear that when the flow rate is large, the frictional force generated between water and the inner partition wall of the liquid-to-be-heated channel 100a is increased, and scale adhesion can be suppressed.
However, the maximum flow velocity in the case where pulsation was applied was 0.75 m / s, which was equal to or less than the case where the flow was continued at a flow velocity of 0.75 m / s or 1.0 m / s. Furthermore, the scale adhesion inhibiting effect is remarkably greater than that of both.
It is considered that the pressure change in the heated liquid channel 100a caused by the pulsation caused a complicated disturbance in the flow of water, which contributed to the effect of suppressing the scale adhesion.

The flow rate shown here is a linear flow rate (m / s) obtained by dividing the volume flow rate (m ³ / s) of high hardness water by the cross-sectional area (m ² ). This may be regarded as a condition that does not depend on the heat transfer channel width, height, or the like.

FIG. 3 shows the results of experiments conducted by the inventor of the present application in four cases while changing the pulsation period. For example, the pulsation cycle of 1 minute is an example in which a flow rate of 0.5 m / s is continued for 1 minute, and then an increment of 0.25 m / s is further applied for 1 minute.
As shown in FIG. 3, scale adhesion was observed when the period was 1 minute and 30 seconds, but scale adhesion was not recognized even after 200 hours from the start of the experiment when the period was 10 seconds or less. Therefore, the period of pulsation should be set to less than 30 seconds, preferably 10 seconds or less.

In addition, here, the scale adhesion preventing effect has been described in the case where the time (A) for providing the reference flow velocity is equal to the time (B) for further increasing the flow velocity, but it is not always necessary to match the two.
If each is set to less than 30 seconds, preferably 10 seconds or less, the same effect can be obtained. Alternatively, even if only A is set to less than 30 seconds, desirably 10 seconds or less, substantially the same effect is obtained.

FIG. 4 shows the experimental results when the flow velocity is changed in four stages with a flow velocity of 0.5 m / s as a reference. The time for maintaining each flow rate is 10 seconds. In the case of 10% increase (+0.05 m / s) and 25% increase (+0.125 m / s), scale adhesion was observed, but 50% increase (+0.25 m / s) and 100% increase (+0.5 m) In the case of / s), no scale adhesion was observed even after 200 hours from the start of the experiment. Therefore, the increment of the flow rate should be determined so as to exceed 25% of the reference flow rate, desirably 50% or more.

In the above, the scale adhesion preventing effect when the pulsation waveform is a rectangular wave has been described. However, the waveform may be determined so as to draw a sine curve. The amplitude and period of the waveform at this time may be determined according to the case of a rectangular wave. For example, if the flow rate is changed according to the following equation (1), the same effect can be obtained.

V = 0.5 + 0.25 × sin (2πt / 20) (1)
Where V: Flow velocity (m / s)
t: Time (seconds).

Furthermore, even if one cycle of the waveform that draws a sine curve is set as one stroke and this is given to the reference flow rate at certain intervals, a remarkable scale adhesion prevention effect can be obtained. This interval is desirably set to about 10 seconds or less, as in the case of the rectangular wave.

The water hardness (270 mg-CaCO ₃ / l) used in this experiment is about five times the average hardness (50-60 mg-CaCO ₃ / l) of tap water in Japan, which is a very high value.
In addition, the water temperature is 80 ° C., and the experiment is conducted by raising the temperature to a limit temperature that can avoid local boiling, and it can be said that the water used for hot water supply was performed under conditions where scale is most likely to occur.
Therefore, the conditions for preventing scale adhesion derived from the experimental results of FIGS. 2 to 4 can be regarded as the most effective conditions.

In the first embodiment, such pulsation is realized by intermittently applying a circulation flow to the water flowing through the heated liquid channel 100a. Therefore, as the water circulation pump 7, for example, a reciprocating pump capable of intermittent water discharge is preferably used.

Embodiment 2. FIG.
In general hot water supply systems for home use, an improvement in the heat exchange rate is required due to the demand for energy saving. As for the heat exchanger, instead of the conventional one using a tube having a diameter of about 1 cm called a heat transfer tube type, a heat exchanger called a laminated type in which thin plates are laminated at intervals of about several mm is used. It is coming.
FIG. 5 is an overall perspective view showing the heat exchanger apparatus 200 of this embodiment.
A heat transfer plate module 200a, which is a stacked heat medium-water heat exchanger of the heat exchanger apparatus 200, is arranged between the end plate 3 and 4 shown in FIG. 8 and the low temperature side heat transfer plate 1 shown in FIG. 7 and the high temperature side heat transfer plate 2 shown in FIG. The number of the low temperature side heat transfer plates 1 and the high temperature side heat transfer plates 2 is not limited to the number shown in FIG.
A front end portion of the heat medium inlet pipe 99 is joined to the heat medium inlet hole 31 formed in the end plate 3. The tip of the heat medium outlet pipe 55 is joined to the heat medium outlet hole 32. The heated liquid inlet pipe 9 is joined to the heated liquid inlet hole 33.

The tip of the heated liquid outlet pipe 5 is joined to the heated liquid outlet hole 34. A heated liquid circulation pipe 6 is branched from the heated liquid outlet pipe 5. The tip of the heated liquid circulation pipe 6 is joined to the heated liquid circulation hole 35 formed in the end plate 3. A circulation pump 7 is attached to the heated liquid circulation pipe 6.
The circulation pump 7 is connected to a controller 8 that controls driving of the circulation pump 7 via a signal line 8a.

FIG. 6 is a plan view showing the low temperature side heat transfer plate 1 in which the low temperature side heat transfer chamber 1b, which is a heated liquid flow path through which the heated liquid flows inside, is formed. At the four corners, a heat medium inlet hole 11, a heat medium outlet hole 12, a heated liquid inlet hole 13, a heated liquid outlet hole 14, and a heated liquid circulation hole 15 are formed.
Further, a partition wall 1a, a partition wall 11a, and a partition wall 12a are provided around the low temperature side heat transfer plate 1, the heat medium inlet hole 11, and the heat medium outlet hole 12, respectively. The heat medium inlet hole 11 and the partition wall 11a form a heat medium inlet channel 11b that is partitioned from the low temperature side heat transfer chamber 1b that is a liquid flow path to be heated. The heat medium outlet hole 12 and the partition wall 12a form a low temperature side heat transfer chamber. A heat medium outlet channel 12b partitioned from the heat chamber 1b is formed.

FIG. 7 is a plan view showing a high temperature side heat transfer plate 2 that is hollow and has a high temperature side heat transfer chamber 2b formed therein. At the four corners of the high temperature side heat transfer plate 2, there are a heat medium inlet hole 21 and a heat medium outlet. A hole 22, a heated liquid inlet hole 23, a heated liquid outlet hole 24, and a heated liquid circulation hole 25 are formed. A partition wall 2a, a partition wall 23a, a partition wall 24a, and a partition wall 25a are provided around the high temperature side heat transfer plate 2, the heated liquid inlet hole 23, the heated liquid outlet hole 24, and the heated liquid circulation hole 25, respectively. . A heated liquid inlet passage 23b partitioned from the high temperature side heat transfer chamber 2b is formed by the heated liquid inlet hole 23 and the partition wall 23a, and separated from the high temperature side heat transfer chamber 2b by the heated liquid outlet 24 and the partition wall 24a. The heated liquid outlet channel 24b thus formed is formed. A heated liquid circulation passage 25b partitioned from the high temperature side heat transfer chamber 2b is formed by the heated liquid circulation hole 25 and the partition wall 25a.

The heat medium inlet channel 11 b of the low temperature side heat transfer plate 1 communicates with the heat medium inlet hole 21 of the adjacent high temperature side heat transfer plate 2. The heat medium outlet channel 12 b of the low temperature side heat transfer plate 1 communicates with the heat medium outlet hole 22 of the adjacent high temperature side heat transfer plate 2.
The heated liquid inlet channel 23 b of the high temperature side heat transfer plate 2 communicates with the heated liquid inlet hole 13 of the adjacent low temperature side heat transfer plate 1. The heated liquid outlet channel 24 b of the high temperature side heat transfer plate 2 communicates with the heated liquid outlet hole 14 of the adjacent low temperature side heat transfer plate 1. The heated liquid circulation passage 25 b of the high temperature side heat transfer plate 2 communicates with the heated liquid circulation hole 15 of the adjacent low temperature side heat transfer plate 1.

In addition, the inner wall surface of the hollow low-temperature side heat transfer plate 1 through which water flows and the inner wall surface of the hollow high-temperature side heat transfer plate 2 through which the heat medium circulate are innumerable for allowing water and heat medium to circulate evenly. Asperities are formed.
Further, the vertical and horizontal lengths of the low temperature side heat transfer plate 1 and the high temperature side heat transfer plate 2, the diameters of the heat medium inlet holes 11 and 21, the diameters of the heat medium outlet holes 12 and 22, and the heated liquid inlet holes 13 and 23 The diameter, the diameter of the heated liquid outlet holes 14 and 24, and the diameter of the heated liquid circulation holes 15 and 25 are not limited to the example shown in FIG.

FIG. 8 is a plan view showing the end plate 3. At the four corners of the end plate 3, a heat medium inlet hole 31, a heat medium outlet hole 32, a heated liquid inlet hole 33, a heated liquid outlet hole 34, and further, A heated liquid circulation hole 35 is formed.

The low temperature side heat transfer plate 1, the high temperature side heat transfer plate 2, and the end plates 3 and 4 are laminated to form one heat transfer plate module 200a. Each of the vertical and horizontal lengths, the heat medium inlet hole, and the heat medium outlet hole The position and diameter of the heated liquid inlet hole, heated liquid outlet hole, and heated liquid circulation hole are the same.

Next, operation | movement of the heat exchanger apparatus 200 in Embodiment 2 is demonstrated with reference to FIG.5, FIG.9 and FIG.10.
As shown in FIG. 9, the water 1000 that is the liquid to be heated in the liquid inlet pipe 9 to be heated flows into the heat transfer plate module 200 a through the liquid inlet hole 33 formed in the end plate 3. The water 1000 that has flowed into the heat transfer plate module 200a first flows into the closest low-temperature side heat transfer chamber 1b, but a part of the water 1000 passes through the heated liquid inlet hole 13 and the heated liquid inlet channel 23b to the other low temperature side. It also flows into the heat transfer chamber 1b. The water 1000 that has passed through the low temperature side heat transfer chambers 1b in parallel joins through the heated liquid outlet channel 24b and the heated liquid outlet hole 14 and flows out to the heated liquid outlet pipe 5 through the heated liquid outlet hole 34. .

A part of the water 1000 flowing through the heated liquid outlet pipe 5 flows again into the heat transfer plate module 200 a through the heated liquid circulating pipe 6 by driving the circulation pump 7. The water 1000 first flows into the nearest low-temperature side heat transfer chamber 1b, but a part flows into the other low-temperature side heat transfer chamber 1b through the heated liquid circulation hole 15 and the heated liquid circulation passage 25b. To do.
Here, the controller 8 performs control so that the circulation pump 7 is repeatedly turned on and off at regular intervals via the signal line 8a.
Thereby, the flow volume of the water 1000 which passes through the area | region from the to-be-heated liquid circulation hole 15 in the low temperature side heat transfer chamber 1b to the to-be-heated liquid exit hole 14 can be increased intermittently, and water can be pulsated.

On the other hand, the heat medium 2000 in the heat medium inlet pipe 99 flows into the heat transfer plate module 200a through the heat medium inlet hole 31 formed in the end plate 3, as shown in FIG. The heat medium 2000 that has flowed into the heat transfer plate module 100a passes through the heat medium inlet channel 11b and flows into the closest high-temperature side heat transfer chamber 2b. It flows into the other high temperature side heat transfer chamber 2b through the inlet channel 11b.
The heat medium 2000 that has passed through the high temperature side heat transfer chambers 2b in parallel with each other joins through the heat medium outlet channel 22b and the heat medium outlet hole 12, and flows out to the heat medium outlet pipe 55 through the heat medium outlet hole 32.

In this way, heat is exchanged between the water 1000 and the heat medium 2000 by the water 1000 and the heat medium 2000 that pass through the adjacent low-temperature side heat transfer chamber 1b and the high-temperature side heat transfer chamber 2b in parallel flow. The temperature of the water 1000 rises with the heat from the heat medium 2000.
For example, when the water 1000 is water having a high hardness component, the vicinity of the heated liquid outlet hole 14 where the water temperature rises most in the low temperature side heat transfer chamber 1b is a place where the scale is most easily attached. Water pulsates and scale adhesion can be prevented.

At this time, since the region where the water 1000 pulsates is only in the vicinity of the heated liquid outlet hole 14 in the low temperature side heat transfer chamber 1b, the heated liquid 1000 is used as the heated liquid inlet pipe 9 or the end plate 3 as in the conventional example. The pressure loss is small as compared with the case of returning to the heated liquid inlet hole 33 formed in. That is, it is possible to reliably pulsate the water 1000 without slowing the speed change and prevent scale adhesion. Further, the capacity or power of the circulation pump 7 can be small.

Further, the water 1000 circulates in the low temperature side heat transfer chamber 1b, but the flow rate of the water 1000 flowing into the low temperature side heat transfer chamber 1b and the flow rate of the heated liquid 1000 flowing out of the low temperature side heat transfer chamber 1b. Can always be kept constant. That is, the hot water supply temperature can be kept constant while preventing scale adhesion.

The heated liquid circulation hole 15 is formed in the low temperature side heat transfer plate 1 in a region where the risk of scale adhesion is high, that is, a region where water becomes high temperature. Specifically, it is desirable to drill in any one of the fan-shaped (quarter circle) regions having a radius of ½ of the diagonal length of the low-temperature heat transfer plate 1 with the heated liquid outlet hole 14 as the center.
The positions of the heated liquid circulation hole 25 drilled in the high temperature side heat transfer plate 2 and the heated liquid circulation hole 35 drilled in the end plate 3 are also the same.

Embodiment 3 FIG.
FIG. 11 is a cross-sectional view showing a heat exchanger apparatus 201 according to the embodiment of the present invention. In addition, although the example which laminates | stacks three each of the low temperature side heat exchanger plates 1x, 1y, and 1z and the high temperature side heat exchanger plates 2x, 2y, and 2z shown in FIG. 11 was shown, it is limited to this about the number of heat exchanger plates. Is not to be done.
12 is a plan view of the end plate 30 of FIG. At the four corners of the end plate 30, a heat medium inlet hole 301, a heat medium outlet hole 32, a heated liquid inlet hole 303, and a heated liquid outlet hole 304 are formed.
In addition to these, through holes 3051, 3052, 3053 for penetrating the heated liquid dispensing pipe are drilled.

FIG. 13 collectively shows a plan view of the low temperature side heat transfer plates 1x, 1y, 1z of FIG. At the four corners of the hollow low temperature side heat transfer plates 1x, 1y, 1z, heat medium inlet holes 11x, 11y, 11z, heat medium outlet holes 12x, 12y, 12z, heated liquid inlet holes 13x, 13y, 13z, Heating liquid outlet holes 14x, 14y, and 14z are formed, respectively.

Further, the low temperature side heat transfer plate 1x is provided with through holes 15x1 and 15x2 for penetrating the heated liquid dispensing pipe. A through hole 15y1 is formed in the low temperature side heat transfer plate 1y. There is no through hole in the low temperature side heat transfer plate 1z.
A partition wall 1ax, a partition wall 11ax, and a partition wall 12ax are provided around the low temperature side heat transfer plate 1x, the heat medium inlet hole 11x, and the heat medium outlet hole 12x, respectively. A heat chamber 1bx is formed. Further, the heat medium inlet channel 11bx is constituted by the heat medium inlet hole 11x and the partition wall 11ax, and the heat medium outlet channel 12bx is constituted by the heat medium outlet hole 12x and the partition wall 12ax.

Similarly, a partition wall 1ay, a partition wall 11ay, and a partition wall 12ay are provided around the low temperature side heat transfer plate 1y, the heat medium inlet hole 11y, and the heat medium outlet hole 12y, respectively. A low temperature side heat transfer chamber 1by is formed. Further, the heat medium inlet channel 11by and the partition wall 11ay constitute a heat medium inlet channel 11by, and the heat medium outlet hole 12y and the partition wall 12ay constitute a heat medium outlet channel 12by.

Similarly, a partition wall 1az, a partition wall 11az, and a partition wall 12az are provided around the low temperature side heat transfer plate 1z, the heat medium inlet hole 11z, and the heat medium outlet hole 12z, respectively. A low temperature side heat transfer chamber 1bz is formed. Further, a heat medium inlet channel 11bz is configured by the heat medium inlet hole 11z and the partition wall 11az, and a heat medium outlet channel 12bz is configured by the heat medium outlet hole 12z and the partition wall 12az.
The low temperature side heat transfer chambers 1bx, 1by, 1bz are heated liquid passages through which the heated liquid flows.

Innumerable irregularities are formed on the inner wall surfaces of the hollow low temperature side heat transfer plates 1x, 1y, and 1z to distribute the liquid to be heated evenly.
Also, the vertical and horizontal lengths of the low temperature side heat transfer plates 1x, 1y, 1z, heat medium inlet holes 11x, 11y, 11z, heat medium outlet holes 12x, 12y, 12z, heated liquid inlet holes 13x, 13y, 13z, The diameters of the heated liquid outlet holes 14x, 14y and 14z and the heated liquid circulation holes 15x, 15y and 15z are not limited to the example shown in FIG.

FIG. 14 collectively shows a plan view of the high temperature side heat transfer plates 2x, 2y, 2z in FIG. Heat medium inlet holes 21x, 21y, 21z, heat medium outlet holes 22x, 22y, 22z, heated liquid inlet holes 23x, 23y, 23z, and to-be-covered are provided at the four corners of the hollow high temperature side heat transfer plates 2x, 2y and 2z. Heated liquid outlet holes 24x, 24y, and 24z are formed.
Furthermore, the high temperature side heat transfer plate 2x is provided with through holes 25x1 and 25x2 for penetrating the heated liquid dispensing pipe. A through hole 25y1 is formed in the low temperature side heat transfer plate 2y. There is no through hole in the low temperature side heat transfer plate 2z.
A partition 2ax, a partition 23ax, and a partition 24ax are provided around the high temperature side heat transfer plate 2x, the heated liquid inlet hole 23x, and the heated liquid outlet hole 24x, respectively. A high temperature side heat transfer chamber 2bx is formed. Further, the heated liquid inlet hole 23x and the partition wall 23ax form a heated liquid inlet channel 23bx, and the heated liquid outlet 24x and the partition wall 24ax form a heated liquid outlet channel 24bx.
A partition wall 2ay, a partition wall 23ay, and a partition wall 24ay are provided around the high temperature side heat transfer plate 2y, the heated liquid inlet hole 23y, and the heated liquid outlet hole 24y, respectively. A high temperature side heat transfer chamber 2by is formed. Further, the heated liquid inlet passage 23by is constituted by the heated liquid inlet hole 23y and the partition wall 23ay, and the heated liquid outlet flow path 24by is constituted by the heated liquid outlet 24y and the partition wall 24ay.

A partition wall 2az, a partition wall 23az, and a partition wall 24az are provided around the high temperature side heat transfer plate 2z, the heated liquid inlet hole 23z, and the heated liquid outlet hole 24z, respectively, and the high temperature side heat transfer plate 2z has a high temperature side. A heat transfer chamber 2bz is formed. Further, the heated liquid inlet passage 23b and the partition wall 23az constitute a heated liquid inlet channel 23bz, and the heated liquid outlet port 24z and the partition wall 24az constitute a heated liquid outlet channel 24bz.

Innumerable irregularities are formed on the inner wall surfaces of the hollow high-temperature side heat transfer plates 2x, 2y, and 2z to distribute the liquid to be heated evenly.
Further, the vertical and horizontal lengths of the high temperature side heat transfer plates 2x, 2y, 2z, heat medium inlet holes 21x, 21y, 21z, heat medium outlet holes 22x, 22y, 22z, heated liquid inlet holes 23x, 23y, 23z, The diameters of the heated liquid outlet holes 24x, 24y, and 24z are not limited to the example shown in FIG.

In the heat exchanger apparatus 201 of this embodiment, the low temperature side heat transfer plates 1x, 1y, 1z and the high temperature side heat transfer plates 2x, 2y, 2z are alternately stacked, and end plates 301 and 401 are provided at both ends. Since the heat transfer plate module 201a is joined to each other, the vertical and horizontal lengths, the positions of the through holes of the heat medium inlet hole, the heat medium outlet hole, the heated liquid inlet hole, and the heated liquid outlet hole The diameter is common.
The through holes 3051, 15x1, 15y1, 25x1, and 25y1 have the same position / diameter and the through holes 3052, 15x2, and 25x2 have the same position / diameter.
Further, these through holes are formed in regions where the risk of scale adhesion is high in the low temperature side heat transfer plates 1x, 1y, and 1z, that is, regions where the liquid to be heated becomes high temperature. Specifically, it is drilled in any one of the fan-shaped (quarter circle) regions having a radius of ½ of the diagonal length of the low-temperature heat transfer plate with the heated liquid outlet hole 14x or 14y or 14z as the center. .

The heat exchanger apparatus 201 includes dispensing pipes 6x, 6y, and 6z for dispensing the circulating water 1000 to the low temperature side heat transfer chambers 1bx, 1by, and 1bz. The dispensing pipe 6x communicates with the low temperature side heat transfer chamber 1bx through a through hole 3053 formed in the end plate 301.
The dispensing pipe 6y includes a through hole 3053 formed in the end plate 301, a through hole 15x2 formed in the low temperature side heat transfer plate 1x, and a through hole 25x2 formed in the high temperature side heat transfer plate 2x. And communicates with the low temperature side heat transfer chamber 1by.
The dispensing pipe 6z includes a through hole 3051 formed in the end plate 301, a through hole 15x1 formed in the low temperature side heat transfer plate 1x, a through hole 25x1 formed in the high temperature side heat transfer plate 2x, and a low temperature side. The heat transfer plate 1y communicates with the low temperature side heat transfer chamber 1bz through a through hole 15y1 formed in the heat transfer plate 1y and a through hole 25y1 formed in the high temperature side heat transfer plate 2y.

Each dispensing pipe 6x, 6y, 6z is connected to a heated liquid circulation pipe main body 6A via a control valve 70. The control valve 70 is connected to the controller 80 via a signal line 80a.
Each of the dispensing pipes 6x, 6y, 6z and the heated liquid circulation pipe main body 6A constitutes the heated liquid circulation pipe.
Other configurations are the same as those in the second embodiment.

The controller 80 controls the control valve 70 via the signal line 80a so that the water 1000 sequentially flows through the dispensing pipes 6x, 6y, and 6z with a time difference.
For example, the valve is opened and closed at a timing as shown in FIG. 15, and the water 1000 is circulated through the pipes 6x, 6y, and 6z.
Other operations are the same as those in the second embodiment.

This pulsates the flow velocity in the vicinity of the heated liquid outlet holes 14x, 14y, and 14z where the water temperature rises most in the low temperature side heat transfer chambers 1bx, 1by, and 1bz, which are the heated liquid flow paths, and ensures scale adhesion. Can be prevented.
At this time, since the liquid to be heated 1000 is circulated to each of the low temperature side heat transfer chambers 1bx, 1by and 1bz with a time difference, the amount of liquid to be heated per unit time sent from the liquid to be heated outlet pipe 5 is It is possible to reduce the pump capacity and power as compared with the first and second embodiments.

In each of the above embodiments, the heat exchanger apparatus incorporated in the hot water supply apparatus has been described. However, the present invention is not limited to this, and the heat exchanger apparatus of the present invention can be applied to, for example, a floor heating apparatus. Can be applied.

Claims (8)

1. A heat exchanger in which a liquid to be heated circulates and has a liquid path to be heated to exchange heat with an external heat medium;
   A heated liquid inlet pipe connected to the inlet of the heated liquid flow path;
   A heated liquid outlet pipe connected to an outlet of the heated liquid flow path through which the heated liquid is discharged;
   A heated liquid circulation pipe branched from the heated liquid outlet pipe and having a tip connected in the middle of the heated liquid flow path;
   An operation method of a heat exchanger apparatus provided with a circulation pump provided in the heated liquid circulation pipe and circulating the heated liquid between the heated liquid flow path and the heated liquid circulation pipe,
   After the heated liquid is heated by heat exchange with the heat medium and flows out of the heated liquid flow path, a part of the heated liquid flows into the heated liquid circulation pipe, The operation method of the heat exchanger apparatus, wherein the heating liquid is pulsated by the intermittent drive operation of the circulation pump, and the heated liquid in which the pulsation occurs again flows into the heated liquid flow path as it is.
2. The operation method of the heat exchanger apparatus according to claim 1, wherein the heated liquid circulation pipe has the tip connected to an outlet side of the heated liquid flow path.
3. The operation method of the heat exchanger apparatus according to claim 1 or 2, wherein the heat exchanger includes a heat transfer tube which is the heated channel through which the heated liquid flows. .
4. The controller operates the circulation pump so that the flow rate of the liquid to be heated flowing in the heat transfer tube is repeated at a cycle of 0.5 m / s and a flow rate larger than this flow rate in a period of less than 30 seconds. The operation method of the heat exchanger apparatus according to claim 3.
5. The controller drives the circulation pump to repeat the flow rate of the liquid to be heated flowing in the heat transfer tube at 0.5 m / s and a flow rate at least 25% larger than the flow rate. The operation method of the heat exchanger apparatus of Claim 3 to do.
6. The heat exchanger includes the high temperature side heat transfer plate having a high temperature side heat transfer chamber in which the heat medium flows, and the low temperature side which is the heated liquid flow path in which the heated liquid flows. The operation method of the heat exchanger apparatus according to claim 1 or 2, wherein the high temperature side heat transfer plates having heat transfer chambers are alternately stacked.
7. The operation method of the heat exchanger apparatus according to claim 6, wherein the heated liquid circulation pipe has a plurality of pipes individually connected to the low-temperature side heat transfer chambers.
8. A heat exchanger in which a liquid to be heated circulates and has a liquid path to be heated to exchange heat with an external heat medium;
   A heated liquid inlet pipe connected to the inlet of the heated liquid flow path;
   A heated liquid outlet pipe connected to an outlet of the heated liquid flow path through which the heated liquid is discharged;
   A heated liquid circulation pipe branched from the heated liquid outlet pipe and having a tip connected in the middle of the heated liquid flow path;
   A circulation pump provided in the heated liquid circulation pipe for circulating the heated liquid between the heated liquid flow path and the heated liquid circulation pipe;
   A controller for controlling the operation of the circulation pump,
   The said controller makes the said circulation pump operate intermittently, The heat exchanger apparatus characterized by the above-mentioned.

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