JPH11325771A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent contamination surely between gas and gas, between which heat exchange is effected under spraying water. SOLUTION: A heat exchanger is provided with a heat exchanging means, effecting heat exchange between a first gas EA and a second gas OA under non-contacted condition, and an operation control means 16, switching automatically a first operation, spraying water W supplied into the first gas EA, whose heat exchange is effected in the heat exchanging means, from a tank 9 and returning excessive water W', recovered in the spraying water under non- evaporated condition, into the tank 9, into a second operation, spraying water W supplied into the second gas OA, whose heat exchange is effected in the heat exchanging means, from the tank 9 and returning the excessive water W', recovered in the spray of water under non-evaporated condition, into the tank 9. In the heat exchanging device having such a constitution, the operation control means 16 is constituted so as to effect the renewal of water or replacing the whole reserved water W in the tank 9 with fresh water W1 upon switching the first operation into the second operation and, thereafter, begin the switched operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for heat exchange between a first gas and a second gas by spraying water on a gas having a low enthalpy to promote heat exchange by evaporation of the water sprayed. To a heat exchange device for increasing the temperature.

More specifically, a heat exchange means for exchanging heat between a first gas and a second gas in a non-contact state is provided, and water supplied from a tank is sprayed on the first gas to be exchanged by the heat exchange means. A first operation of returning the excess water recovered in an unevaporated state to the tank in the watering, and watering the supply water from the tank to the second gas to be heat-exchanged by the heat exchange means, and The present invention relates to a heat exchange apparatus having a configuration capable of selectively performing a second operation for returning surplus water recovered in a state to a tank, and including operation control means for automatically switching between the first operation and the second operation. .

[0003]

2. Description of the Related Art Conventionally, in this type of heat exchange apparatus, while the amount of water stored in a tank decreases due to evaporation of sprinkled water, fresh water is automatically supplied to the tank. Regarding the switching between the first operation and the second operation, it is merely switching to which gas the water supplied from the tank is sprayed, and regardless of the switching between the first operation and the second operation, Was directly used for watering (see, for example, JP-A-61-252488).

[0004]

In this type of heat exchange apparatus, the heat exchange between the first gas and the second gas is performed in a non-contact state, and there is no contamination between the gases due to the contact between the gases. Therefore, for example, it is often used for heat exchange between gas containing pollutants and gas required for cleanliness, such as heat exchange between exhaust gas and air supply for the purpose of heat recovery in a clean room. In some cases, one gas is contaminated by pollutants contained in the other gas.

[0005] That is, although there is no direct contact between gases in the conventional apparatus, for example, excess water recovered by watering the first gas in the first operation is first contacted by water-water contact during watering.
It becomes polluted by the pollutants in the gas, and the excess water is returned to the tank, thereby contaminating the stored water in the tank. In this state, the first operation is switched to the second operation. As a result, the second gas is contaminated by using the water stored in the tank for watering the second gas.

In view of this situation, the main problems of the present invention are:
It is to ensure that contamination between the gases to be heat-exchanged can be reliably prevented while adopting a method in which surplus water generated by watering is returned to the tank and reused for watering.

[0007]

Means for Solving the Problems [1] In the invention according to the first aspect, the operation control means for automatically switching the first operation and the second operation is replaced by the first operation and the second operation. At the time of switching, the water is automatically updated so that all the stored water in the tank is replaced with fresh water, and then the operation at the switching destination is started.

[0008] According to this configuration, for example, surplus water returned to the tank by sprinkling water on the first gas in the first operation is contaminated by pollutants in the first gas, thereby contaminating the water stored in the tank. Even in the following second operation, since the tank stored water whose total amount has been replaced with fresh water is sprinkled into the second gas, the second gas is contaminated by the stored water in the first operation. Is not contaminated. Similarly, even if surplus water returned to the tank by watering the second gas in the second operation is contaminated by contaminants in the second gas, thereby contaminating the stored water in the tank, In the first operation, since the tank stored water whose whole amount has been replaced with fresh water is sprinkled into the first gas, the first gas is not contaminated due to the stored water contamination in the second operation. .

Therefore, as compared with the conventional apparatus in which the first gas and the second gas are simply subjected to heat exchange in a non-contact state to prevent gas-to-gas contamination, the other gas is contaminated by the contaminants contained in one gas. It is more suitable for heat exchange between gas containing pollutants and gas requiring cleanliness, such as heat exchange between air supply and exhaust for the purpose of heat recovery in a clean room. It becomes a heat exchange device.

By the way, in order to avoid the above-mentioned gas-gas contamination in which water used for watering is used as a medium, Japanese Patent Application Laid-Open No.
As can be seen in Japanese Patent No. 8148, a non-circulating water supply system such as a temporary supply of city water as water for watering is adopted, and a first operation tank and a second operation tank are separately provided. It is conceivable to install it separately, but in the case of a non-circulating water supply type, the water consumption increases and the cost increases, and the efficiency of air-water contact decreases when the amount of water spray is reduced to reduce the water consumption. The improvement of heat exchange efficiency by water spraying is limited to a low level. Furthermore, the temperature of the water to be supplied fluctuates temporarily, and the effect of water spraying on heat exchange changes to make heat exchange unstable. And the like. On the other hand, in the case where separate tanks are provided, there are problems such as an increase in the size of the apparatus due to the provision of the tanks, an increase in the cost of the apparatus, and a complicated maintenance.

On the other hand, the invention according to claim 1 basically adopts a form in which surplus water in sprinkling is returned to the tank and reused for sprinkling. Even when discarded, compared to the non-circulating water supply form as described above, it is possible to reduce the water consumption while making the watering amount sufficient and effectively improving the heat exchange efficiency by watering, Further, the temperature of the water to be sprinkled is also stabilized at a constant equilibrium temperature by repeated contact with water, so that stable heat exchange can be maintained. Further, since the tank is used for both the first operation and the second operation, the size of the apparatus can be reduced, the apparatus cost can be reduced, and the maintenance can be facilitated as compared with the case where separate tanks are provided. .

When only the second gas is prevented from being polluted by the pollutants contained in the first gas, the water renewal is performed only when the first operation is switched to the second operation. In carrying out the invention according to claim 1, the water renewal is always performed at the time of switching from the first operation to the second operation and at the time of switching from the second operation to the first operation. No need.

[2] In the invention according to the second aspect, the operation control means may determine that the detected water quality of the water stored in the tank is equal to or lower than the set lower limit water quality during the first operation or the second operation. Every time the temperature is lowered, the water stored in the tank or a part thereof is replaced with fresh water so that the water is automatically renewed.

According to this configuration, during the first operation or the second operation, the excess water returned to the tank is polluted by the pollutant contained in the gas to be sprinkled, so that the pollutant is reused when the water is reused. Is gradually accumulated, and even if the contamination of the tank storage water progresses, the above-mentioned water renewal is performed every set time or every time the detected water quality of the tank storage water decreases to the set lower limit water quality. Stopped by a certain limit.

Accordingly, even if the water renewal is performed at the time of switching between the first operation and the second operation, the water renewal is not performed even if the water stored in the tank is seriously contaminated and the constituent material of the tank itself is contaminated. Can be prevented from being contaminated by contaminants remaining in the tank, and from this point, gas-to-gas contamination can be more reliably prevented.

In addition, the deterioration of the quality of the water stored in the tank due to the contaminants can be stopped to a certain limit, thereby preventing problems such as poor water spray and poor heat exchange caused by the deterioration of the water quality.
This is particularly effective when the target gas is a gas containing a large amount of pollutants.

[3] In the invention according to claim 3, the operation control means is configured to supply fresh water to the tank after draining all stored water in the tank during the water renewal.

According to this configuration, in renewing the water, fresh water is supplied to the tank after draining all the contaminated water stored in the tank. It is possible to prevent contamination by mixing.

Therefore, if this water renewal mode is applied to water renewal at the time of switching between the first operation and the second operation, water with less risk of contamination can be sprinkled in the operation at the switchover destination, whereby the gas Contamination can be more reliably prevented. Further, if this water renewal mode is applied to the water renewal during the first operation or the second operation, the contamination of the tank stored water exceeding a certain limit can be more reliably prevented, and the contamination of the tank component itself can be more reliably prevented. In this regard, gas-to-gas contamination can be more reliably prevented, and inconveniences such as poor water spray and poor heat exchange caused by deterioration of water quality can be more reliably prevented.

[4] In the invention according to claim 4, the operation control means is configured to automatically perform tank cleaning at the time of the water renewal.

According to this configuration, when the water is renewed, the pollutant cannot be completely removed only by discharging the water stored in the tank, and even if the pollutant remains in the tank due to adhesion to the tank, the renewal of the water is not required. The remaining pollutants can be eliminated by washing the tank, and the contamination due to the remaining contaminants of fresh water to be newly supplied can be prevented, whereby gas-to-gas contamination can be more reliably prevented.

[5] In the invention according to claim 5, the operation control means is configured to repeat the water renewal operation of replacing all stored water in the tank with fresh water a plurality of times as the tank cleaning.

According to this configuration, the tank cleaning is performed only by repeating the drainage of the tank stored water and the supply of the fresh water. Therefore, in performing the tank cleaning, a dedicated device is provided separately from the drainage unit and the fresh water supply unit. Compared with the provision of the cleaning means, the device configuration can be simplified, the device can be easily manufactured, and the device cost can be reduced.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows that the exhaust heat EA from a clean room led by an exhaust duct 1 and the outside air OA introduced into the clean room led by an outside air duct 2 are exchanged. (I.e., a heat exchange device that recovers cold heat during cooling and recovers warm heat during heating).

Reference numeral 3 denotes a fin tube type exhaust side heat exchanger for exchanging heat between the exhaust EA and the heat medium R, and 4 denotes an outside air OA and the heat medium R.
Tube type outside air heat exchanger for exchanging heat
Is a heat medium circulating path through which the heat medium R is circulated by the circulation pump 6 through the heat exchangers 3 and 4;
(The so-called run-around type) in which the exhaust air EA and the outside air OA are heat-exchanged in a non-contact state via the circulating heat medium R.

Reference numeral 7 denotes an exhaust-side water sprinkler that sprays water to the exhaust EA in a form of precipitation on the exhaust-side heat exchanger 3, and 8 denotes an outside air-side heat exchanger 4.
An outside air sprinkler that sprinkles the outside air OA in the form of precipitation
Is a tank for supplying water W for watering to each of the water sprayers 7, 8 through water supply channels 11, 12 by a watering pump 10, and 13 is a tank 9 for storing excess water W 'collected in an unevaporated state in watering for the exhaust EA. An exhaust-side return water passage 14 is a return-side water return passage for returning surplus water W ′ recovered in an unevaporated state to the tank 9 in sprinkling water to the outside air OA.

V1 is an exhaust-side sprinkling valve that starts and stops water spraying on the exhaust EA by opening and closing the exhaust-side water supply path 11, and V2 is an outside air-side sprinkling valve that starts and stops watering on the outside air OA by opening and closing the outside air-side water supply path 12. V3 is a drain valve for draining the stored water W in the tank 9, V4 is a ball tap valve for automatically replenishing the tank 9 with fresh water Wi from the replenishing water channel 15 when the level of the stored water in the tank is lowered, and V5 is a refilling water channel 15. This is the main valve of the makeup water channel that opens and closes.

Reference numeral 16 denotes an operation controller (operation control means). The operation controller 16 controls the exhaust gas EA as the first gas.
And the surplus water W 'in the sprinkling is returned to the tank 9, whereas the sprinkling to the outside air OA as the second gas is stopped, and conversely, the sprinkling to the outside air OA as the second gas. Then, while returning the surplus water W ′ in the water spraying to the tank 9, the second operation in which water spraying to the exhaust gas EA as the first gas is stopped is performed by the enthalpy ho of the outside air OA detected by the outside air sensor 17. Automatically switch based on.

More specifically, the enthalpy ho of the outside air OA is equal to the enthalpy he of the exhaust EA (in this example, the enthalpy he of the exhaust EA is treated as a known constant value assuming that the temperature and humidity of the clean room are kept constant by air conditioning). When the pressure is also high (ho> he), as shown in FIG. 2A, the circulation pump 6 is ON, the watering pump 10 is ON, the exhaust side watering valve V1 is open, and the outside air side watering valve V2 is open. With the valve closed and the drain valve V3 closed and the supply water main valve V5 opened, the first operation of only spraying water to the exhaust EA is performed. Promotes heat exchange between the exhaust EA and the outside air OA (in other words, recovery of cold heat from the exhaust EA to the outside air OA).

The enthalpy ho of the outside air OA is the exhaust E
A is lower than the enthalpy he of A, and the difference is the set value Δh
2 (hz <ho <he−Δh)
As shown in (b), the circulation pump 6 is ON, the watering pump 10 is ON, the exhaust-side watering valve V1 is closed, the outside air-side watering valve V2 is open, the drainage valve V3 is closed, and the main supply water passage is provided. With the valve V5 open, a second operation is performed in which only water is sprayed to the outside air OA, whereby the exhaust EA and the outside air OA are removed by removing vaporization heat on the outside air side due to the evaporation of the sprinkled water W. Heat exchange (in other words, recovery of heat from exhaust EA to outside air OA) is promoted.

The operation controller 16 determines that the difference between the enthalpy ho of the outside air OA and the enthalpy he of the exhaust EA is equal to or smaller than the set value Δh (he−
When Δh ≦ ho <he), as shown in FIG. 3A, the circulation pump 6 is turned off, the watering pump 10 is turned off, the exhaust side watering valve V1 is closed, and the outside air side watering valve V2 is closed. , The drain valve V3 is closed and the supply water main valve V5 is opened to stop the heat exchange operation.

When the enthalpy ho of the outside air OA is lower than the set lower limit hz (ho <hz <he-.DELTA.h), as shown in FIG. 3B, the circulation pumps 6 are turned on and the watering pumps 10 are turned on. OFF, exhaust-side watering valve V1 ... closed, outside air-side watering valve V2 ... closed, drainage valve V3 ... closed, supply water main valve V5 ... Perform heat exchange operation by circulation only.

That is, even when the enthalpy ho of the outside air OA is lower than the enthalpy he of the exhaust air EA, when the difference between them is small (he−Δh ≦ ho <he), heat recovery from the energy consumed in the operation of the apparatus. The heat exchange operation is stopped by stopping both circulation of the heat medium and water spraying, and when the enthalpy ho of the outside air OA is extremely low (ho <hz), the water W Is at risk of freezing,
The heat exchange operation is performed only by the circulation of the heat medium without watering.

When the operation controller 16 automatically switches the operation according to the enthalpy ho of the outside air OA as described above, the operation controller 16 switches the operation from the first operation to the second operation. In the case where the second operation at the switching destination is performed, the water renewal for automatically replacing all the stored water W in the tank 9 with the fresh water Wi is performed in the case of performing the second operation at the switching destination. It is.

More specifically, in performing the second operation at the switching destination, first, as shown in FIG. 4A, the watering pump 10 is turned off, the exhaust side watering valve V1 is opened, and the outside air side watering valve is opened. V2: open, drain valve V3: open, supply water main valve V5: closed, drain all water W in tank 9 together with water W in the pipe, and after draining, As shown in (b), the watering pump 10 is OFF, the exhaust-side watering valve V1 is open, the outside air-side watering valve V2 is open, the drainage valve V3 is closed, and the supply water main valve V5 is opened. Then, a fresh water Wi is supplied to the tank 9 by automatic replenishment by the ball tap valve V4 to perform a water update operation of replacing all the stored water W in the tank 9 with the fresh water Wi,
Then, after the water renewal operation is automatically repeated twice, the operation is shifted to the second operation at the switching destination.

The operation controller 16 is configured to automatically execute the water renewal operation only once at a set time during the execution of the first operation.

In other words, even if the surplus water W ′ returned to the tank 9 by sprinkling water on the exhaust EA in the first operation is contaminated by the pollutants in the exhaust EA, the stored water W in the tank 9 is contaminated. By automatically performing the above-mentioned water update at the time of operation switching, in the next second operation, the tank storage water W whose entire amount has been replaced with fresh water Wi is sprinkled to the outside air OA. This prevents the outside air OA introduced into the clean room from being contaminated due to the stored water contamination in the first operation.

Further, during the first operation, the surplus water W ′ returned to the tank 9 is contaminated by pollutants contained in the exhaust gas EA. Even if the contamination of W progresses, the water in the tank stored water W is stopped to a certain limit by performing the water renewal at the set time as described above, whereby the contamination of the tank stored water W becomes severe and the tank configuration is increased. Even if the renewal of water is performed at the time of switching between the first operation and the second operation, the fresh water Wi newly supplied by the renewal of water is contaminated by the contaminants remaining in the tank because the material itself is contaminated. In addition to preventing inconvenience, it also prevents inconveniences such as poor watering and poor heat exchange caused by deterioration of water quality.

[Another Embodiment] The heat exchange means for exchanging heat between the first gas and the second gas in a non-contact state includes the exhaust side heat exchanger 3 and the outside air side heat exchanger as described in the above embodiment. 4.
It is not limited to the run-around type including the heat medium circulation path 5, but may be a type in which both gases exchange heat in a non-contact state through a heat pipe, or a type in which both gases are exchanged through a partition plate that forms a heat transfer surface. A type in which heat exchange is performed in a non-contact state may be used.

In the above embodiment, the water is updated only at the time of switching from the first operation to the second operation. However, the second gas is contaminated by the pollutants contained in the first gas, and When switching from the first operation to the second operation, for example, when it is necessary to prevent both contamination of the first gas by contaminants contained in the second gas, and the second operation
The water update may be performed each time the operation is switched from the operation to the first operation.

In the above-described embodiment, the water update is performed every set time only during the execution of the first operation. However, in some cases, the water update is performed every set time in each of the first operation and the second operation. It may be performed.

Further, instead of performing the water updating during the operation at every set time, it may be carried out every time the quality of the tank stored water falls to the set lower limit water quality based on the detection of the water quality of the tank stored water. In addition, in the water update at the time of operation switching, all the stored water in the tank is replaced.On the other hand, for the water update during the operation every set time or every time the quality of the tank stored water decreases to the set lower limit water quality, the tank storage is replaced. Only a part of the water may be replaced.

The first gas and the second gas to be heat-exchanged are not limited to the combination of the exhaust gas and the outside air, but may be any gas that exchanges heat for any purpose.

[Brief description of the drawings]

FIG. 1 is a diagram showing a device configuration.

FIG. 2 is a diagram showing an operation mode of a first operation and a second operation.

FIG. 3 is a diagram showing another operation mode.

FIG. 4 is a diagram showing an operation mode of a water update operation.

[Explanation of symbols]

 3, 4, 5 Heat exchange means 9 Tank 16 Operation control means EA First gas OA Second gas W Water W 'Excess water Wi Fresh water

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor O Kashiwamori 2-6-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo Co., Ltd.

Claims (5)

[Claims] 1. A heat exchange means for exchanging heat between a first gas and a second gas in a non-contact state, wherein water supplied from a tank is sprinkled onto the first gas to be exchanged by the heat exchange means. A first operation of returning surplus water recovered in a non-evaporated state to the tank in the spraying, and sprinkling water supplied from the tank to the second gas to be heat-exchanged by the heat exchange means, And a second operation for returning surplus water recovered in a non-evaporated state to the tank can be selectively performed, and an operation control means for automatically switching between the first operation and the second operation is provided. A heat exchange device provided, wherein the operation control means automatically performs a water update for replacing all stored water in the tank with fresh water when switching between the first operation and the second operation, and thereafter switches the operation control means. Driving ahead Heat exchanger that is in the configuration to start. 2. The method according to claim 1, wherein the operation control means performs the first operation or the second operation, at each set time or every time the detected water quality of the tank stored water decreases to a set lower limit water quality. The heat exchange device according to claim 1, wherein a water renewal for automatically replacing all or a part of the stored water in the tank with fresh water is automatically performed. 3. The method according to claim 1, wherein the operation control means includes: draining all stored water in the tank during the water renewal;
2. A structure in which fresh water is supplied to the tank.
Or the heat exchange device according to 2. 4. The heat exchange apparatus according to claim 1, wherein the operation control unit is configured to automatically perform tank cleaning at the time of the water renewal. 5. The heat exchange apparatus according to claim 4, wherein the operation control means is configured to repeat a water renewal operation of replacing all stored water in the tank with fresh water a plurality of times as the tank cleaning.