JPH0776653B2 - Direct contact type condenser and heat cycle device using the same - Google Patents

Description

The present invention relates to a direct contact condenser and a heat cycle device using the same.

[Conventional technology]

Conventionally, as a condenser of a heat pump device such as a refrigerator or an air conditioner, or a heat recovery device such as geothermal binary power generation or ocean temperature difference power generation, a gas heat medium to be condensed and a cooling fluid are passed through a metal wall. A method of indirectly exchanging heat is often used. For example, in a condenser proposed for binary power generation, a method of condensing and liquefying a gas is used by bringing the gas to be condensed into contact with the outer surface of a heat transfer tube in which a cooling fluid flows inside the condensing chamber. Generally, a shell-and-tube heat exchanger is used that has grooves on the tube surface or finned tubes to increase the heat transfer area.
That is, the cooling water is passed through the tube that is the heat transfer tube,
The gas heat transfer medium introduced into the shell is condensed on the outer wall of the tube.
It was condensed due to heat transfer between gases. Since this solid-gas heat transfer has lower heat transfer characteristics than liquid-gas heat transfer, the condenser is enlarged to increase the heat transfer area, and grooves or irregularities are formed on the tube surface. Some ideas were made to do so.

[Problems to be Solved by the Invention]

For the above-mentioned reasons, the conventional condenser has a problem that the size of the condenser is increased and the cost of the heat transfer tube surface is increased. Furthermore, there has been a problem that condensate and impurities such as oil in the heat medium adhere to the outer surface of the heat transfer tube, resulting in a significant decrease in heat transfer performance.

The present invention has been made to solve the above problems, and its object is to improve the heat transfer performance of a condenser by directly condensing a gas to be condensed with a cooled liquid to condense it. Therefore, it is an object of the present invention to provide a compact and inexpensive condenser that is improved, and to provide an efficient heat cycle device.

[Means for Solving the Problems]

In order to achieve the above object, a condenser for introducing a gas to be condensed into a condensing chamber having a plurality of heat transfer tubes (tubes) through which a cooling fluid flows, and condensing the gas, The condenser according to the present invention is provided with bubble generating means at the bottom of the condensing chamber for filling the condensing chamber with the liquid cooled by the heat transfer tube and introducing the gas to be condensed into the filling liquid in the form of bubbles. It is characterized by that.

And the present invention also forcibly circulates the heat medium between the evaporator and the condenser arranged in the closed piping system, liquefying the gas heat medium vaporized by the evaporator by the condenser, In the heat cycle device in which the liquid heat medium is circulated to the evaporator again, the condenser comprises a shell-and-tube heat exchanger in which a plurality of tubes are laterally arranged in the shell. The heat medium flows through the shell side of the exchanger and the heat radiation fluid flows through the tube side to form a condensing chamber inside the condensing chamber, and the heat medium is in a liquid state and the tube of the tube is in the condensing chamber. Introducing a gas heat transfer medium for introducing the gas heat transfer medium vaporized in the evaporator in the form of bubbles into the lower part of the liquid layer packed in the condensation chamber, which is packed in an amount sufficient to cover substantially all of the wall surface. Means is provided and the liquid layer position above the means Liquid heating medium outlet port for withdrawing part of al liquid toward the evaporator to provide a thermal cycling apparatus is characterized in that provided in the condensation chamber. At that time, if a power recovery turbine is arranged in the gas heat transfer medium passage from the evaporator to the condenser, it can be configured as a device for recovering power from geothermal heat or factory waste heat. As the heat medium to be circulated in the system, the most commonly used is a working heat medium used in a low temperature difference energy recovery cycle such as CFC or ammonia.

[Work]

With the above configuration, the gas heat transfer medium (air bubbles) in the condensing chamber
However, since it directly contacts the liquid heat medium cooled by a large number of heat transfer tubes and condenses it by heat transfer between gas and liquid, the heat transfer performance is better than that of the conventional gas-solid heat transfer in a condenser. improves. The gas heat medium introduced into the condensing chamber is
Since it is integrated with the liquid heat medium in the condensation chamber of the same substance, the operation of extracting this liquid is also stabilized. Furthermore, since the heat transfer medium gas is made into fine bubbles by the bubble generating means and is introduced into the liquid in the condensation chamber, the cooling rate of the gas is increased, and the generated bubbles stir the liquid around the heat transfer tube. ， The heat transfer performance between the liquid and the heat transfer tube is also improved. Therefore,
It is possible to configure a condenser that is compact and has extremely high condensation efficiency. By using this, a very efficient heat cycle device and power recovery device can be configured.

〔Example〕

 Hereinafter, the present invention will be described based on illustrated embodiments.

FIG. 1 is a longitudinal sectional view of a condenser according to the present invention, and FIG.
FIG. 2 is an enlarged cross-sectional view taken along the line AA in which a part of FIG. 1 is broken.
As shown in the figure, in the condenser of the present invention, both end openings of a substantially cylindrical condenser body 1 whose central axis is oriented in the horizontal direction are closed by end plates 2a and 2b, and the inside is divided by a partition wall 3. The condensing chamber 4 and the cooling water supply chamber 5 are formed.

Inside the condensing chamber 4, a large number of U-shaped heat transfer pipes 6 that circulate in the condensing chamber 4 and have both ends penetrating the partition wall 3 are arranged with their axes substantially horizontal. Also the condensation chamber 4
Has a gas inlet 7 on the lower surface, a gas outlet 8 for discharging an inert gas on one end of the upper surface, and a condensate outlet 9 on the side surface substantially in the center, and a radius of the condenser 4 respectively. It is formed so as to project outward in the direction. The condensing chamber 4 is filled with a CFC liquid 10, which is the same substance as the gas to be condensed, which will be described later, so that substantially all of the heat transfer tube 6 is immersed in the liquid. In addition, 11 is condensed CFC liquid 10
It is a control plate for controlling the flow of. As shown in FIG. 2, the control plate 11 composed of a substantially rectangular plate-like body has the upper and lower edges on the long side wound around the U-shaped heat transfer tubes 6 located at the left end and the right end. Installed almost vertically. Due to the presence of the control plate 11, during operation, a flow in which the condensate circulates and descends is formed on the side of the group of heat transfer tubes 6.

As shown in FIG. 1, the cooling water supply chamber 5 has a cooling water outlet 12 at an upper portion and a cooling water inlet 13 at a lower portion so as to project outward in the radial direction of the cooling water supply chamber 5. In addition, the inside of the upper chamber 5a and the lower chamber 5b is protected by the shield plate 14
Both ends of each heat transfer tube 6 are opened in the upper chamber 5a and the lower chamber 5b. Therefore, the lower chamber 5b constitutes a cooling water inlet header chamber for each heat transfer pipe 6, and the upper chamber 5a constitutes a cooling water outlet header chamber for each heat transfer pipe 6.

A bubble generating plate 15 is horizontally installed on the bottom surface of the condensing chamber 4 above the gas inlet 7. The bubble generating plate 15 has a size that extends over substantially the entire length of the bottom surface of the condensing chamber 4 in the longitudinal direction.
An air supply chamber 16 is formed between the condenser body 1 and the condenser body 1. In the illustrated embodiment, the bubble generating plate 15 has, as shown in FIG. 3, a rectangular flat plate portion with holes 15a having a diameter of 4 mm and 5 holes in the lateral direction.
It consists of 8 perforated plates with 7 rows in the vertical direction. The number and diameter of the holes 15a of the bubble generating plate 15 are
It is necessary to properly determine the thermophysical property value of the fluid substance to be condensed, but in order to minimize the flow resistance when the gas passes through this hole, the total area of the hole 15a is set to the diameter cross-sectional area of the gas inlet 7. It is suitable that they are almost equal. In addition, the number of rows and their positions are related to the number of tubes at the bottom of the heat transfer tube group, etc., and are arranged to enhance the stirring effect of the liquid around the heat transfer tubes by the bubbles. As a result, the heat transfer performance between the liquid and the heat transfer tube can be significantly improved. In addition, 15c along the longitudinal direction is vertically attached to the back surface of the bubble generating plate 15,
The strength of the bubble generating plate 15 made of a thin plate is reinforced. In addition to the above-described bubble generating plate, a porous tube can be used as the bubble generating means.

The operation of the condenser configured as described above will be described by taking as an example the case where chlorofluorocarbon gas is used as the gas to be condensed.
First, when the cooling water 17 is made to flow from the cooling water inlet 13 into the lower chamber 5b of the cooling water supply chamber 5, the cooling water 17 flows through the heat transfer tube 6 and again in the upper chamber 5a of the cooling water supply chamber 5. It passes through and is discharged from the cooling water outlet 12. When the heat transfer tube 6 is cooled by this, the CFC liquid 10 filled in the condensing chamber 4 is cooled by the heat transfer tube 6. At that time, the heat transfer between the heat transfer tube 6 and the chlorofluorocarbon liquid 10 is heat transfer between the solid and the liquid, so that the heat transfer performance is better than that between the solid and the gas.

When CFC gas is introduced as bubbles 20 (Fig. 2) into the cooled CFC liquid 10 through the bubble generation plate 15, the CFC liquid 10 is generated by the CFC liquid 10 as it rises above the condensing chamber 4. Cools and condenses. Further, in the condenser of the present invention, since the CFC gas is blown from the lower part of the CFC liquid,
The agitation due to the blowing of the bubbles strongly occurs, and particularly, the diffusion flow is generated at the interface between the heat transfer tube 6 and the liquid, so that the heat transfer between the heat transfer tube 6 and the chlorofluorocarbon liquid 10 is greatly promoted. In this way, since the condensation is performed by the heat transfer in which the CFC gas bubble 20 and the CFC liquid 10 are in direct contact with each other, the heat transfer performance is very good as compared with the conventional condensation by the gas-solid heat transfer. That is, the conventional heat transfer coefficient due to condensation between gas and solid was 300 to several thousand and several hundreds kcal / m ² ° C. However, in the condensation between gas and liquid of the present invention, the heat transfer performance was several thousand kcal / m. ² ℃ h
It is possible to

The condensate that has been condensed and liquefied rises to the upper part of the condensing chamber 4 and then descends. The descending flow 18 is controlled by the control plate 11 so as to flow along the inner peripheral surface of the condensing chamber 4, and again the central part of the room. It moves to and becomes an upflow. During such stirring and circulation of the liquid, the liquid corresponding to the condensed portion is taken out from the condensed liquid take-out port 9 which is present in the substantially central portion of the chamber without bubbles substantially flowing out. When the CFC gas is mixed with the inert gas 19, the inert gas 19 is appropriately discharged from the inert gas outlet 8 to the outside of the condensing chamber 4.

Although this liquid-gas direct contact operation is continuously performed, in the initial stage of operation, the CFC liquid 10 in the condensing chamber 4 is sufficiently cooled and then CFC gas is introduced from the gas inlet 7. The pre-cooling of the CFC liquid 10 is performed in the air supply chamber 16 as well.
Can be performed in a full state. Then, when the introduction of the CFC gas is started in a state where the air supply chamber 16 is filled with the CFC liquid 10, the CFC liquid in the gas supply chamber 16 is discharged at the pressure of the CFC gas introduced and is heated by the heat of the CFC gas. After evaporating, the space will eventually be filled with CFC gas, and thereafter, continuous operation will be performed in that state.

FIG. 4 shows a thermal cycler using the above-mentioned condenser. In Fig. 4, 1 is the above-mentioned condenser and 2
Reference numeral 2 denotes an evaporator. A pump 24 and a throttle valve 25 are provided in a liquid pipe 23 leading from the liquid outlet 19 of the condenser 1 to the evaporator 22, and the evaporator 22 is connected to the gas inlet 7 of the condenser 1. A high-pressure pipe 26 is arranged in the interior of the cylinder to form a closed heat cycle in which CFCs circulate as a heat medium. The evaporator 22 in FIG. 4 is a heat exchanger that uses high-temperature water as a heat removal fluid, and uses, for example, a shell-and-tube heat exchanger,
An evaporator can be formed in the shell by passing hot water in the tube and a heat transfer liquid in the shell. Further, a normal fin tube type coil may be used, and the heat transfer liquid may be passed through the coil. In this case, as shown in FIG. 5, high temperature gas may be passed through the surface of the heat exchange coil 22a as a heat removal fluid. In any case, since the evaporator 22 has a function of cooling the heat removal secondary fluid, it constitutes a heat absorbing device such as a refrigerator or an air conditioner.

The feature of this heat cycle device is that, as described above, the condenser 1 is a shell-and-tube heat exchanger in which a large number of tubes 6 are arranged in the shell in the lateral direction. A heat transfer medium (CFC) and a heat dissipation fluid (cooling water) flow through the tube 6 to form a condensing chamber in the shell, and the heat transfer medium is in a liquid state in the condensing chamber. In the bottom of the liquid layer, fill the evaporator with a sufficient amount to cover substantially all of the tube wall surface.
A gas heat medium introducing means 15 for introducing the gas heat medium vaporized in 22 in the form of bubbles is provided, and liquid heat for extracting a part of the liquid from the liquid layer position above this means 15 toward the evaporator. The medium outlet 19 is provided in the condensing chamber, and during operation, the condensing operation is always performed by direct heat exchange of liquid-gas in the condensing chamber. At that time, during operation, in order to always retain a sufficient amount of liquid in the condensing chamber so as to cover almost all the tube wall surfaces of the tubes 6, the rotation of the pump 24 with the detection value by the liquid level detector 27 as the indicated value. The control can be performed by the number control or the opening control of the control valve 28 provided in the liquid pipe line on the suction side of the pump 24. Thereby, the condensing operation of the heat transfer medium in the closed cycle is performed by direct heat exchange between the gas heat transfer medium bubbles and the liquid heat transfer medium, and further, the stirring of the liquid heat transfer medium is assisted by the bubbles ( In particular, since the liquid film around the outer wall of the tube diffuses), the heat transfer efficiency between the cooling water and the liquid heat medium is improved, so that the condensation efficiency is improved, and the heat transfer from the gas heat medium to the cooling water is extremely high. The original condensing behavior can be completely realized even if the capacity of the condenser itself is not so large.

FIG. 6 shows a thermal cycler similar to that of FIG. 4 except that the power is recovered by using the high pressure gas heat medium obtained in the evaporator 22. That is, a turbine 30 is provided in a high-pressure gas pipe line 26 that leads from the evaporator 22 to the condenser 1, and electric power is taken out by a generator 31 by the turbine 30. Such a power recovery device is applied to use excess hot water in a hot spring or a factory as a heat source, and therefore, the evaporator 22 uses one that can efficiently exchange heat with the hot water.

For example, as shown in FIG. 7, by arranging a jet pipe 34 for jetting hot water or steam at the bottom of the hot water tank 33, the hot water in the tank 33 is stirred and the high temperature is maintained. The heat exchange coil 35 through which the liquid heat medium obtained in the condenser 1 flows is immersed in the water tank 33. Further, a chamber 36 (evaporator) having a large internal volume is also immersed in the hot water tank 33, and the heating medium which has passed through the coil 35 and is heated is injected into the chamber 36 to be vaporized. Inside the chamber 36, a heat transfer tube through which hot water in the tank flows can be appropriately arranged. As a result, in the chamber 36 (evaporator), high-pressure heat medium vapor is efficiently obtained, and the high-pressure vapor is used to drive the turbine 30. The heat medium gas that has passed through the turbine 30 returns to the condenser 1 again and is liquefied.

In the above-mentioned embodiment, an example in which CFC is used as the working medium has been shown, but the same operation can be performed using a normal heat medium used in the low temperature difference energy recovery cycle such as ammonia.

〔effect〕

As described above, in the condenser according to the present invention, the gas heat transfer medium becomes bubbles and comes into direct contact with the cooled liquid heat transfer medium in the condensation chamber, and is condensed by heat transfer between the gas (bubble) and liquid. Compared with the conventional gas-solid (heat transfer tube) heat transfer in a condenser, the heat transfer performance is significantly improved, and the liquid heat transfer medium inside the condensing chamber is agitated by the bubbles of the gas heat transfer medium. The heat transfer between the solid and liquid is extremely good, and a large condensation effect can be obtained even with a small heat transfer area. For this reason,
The condenser can be downsized, and when used in a heat cycle device, it can be configured as an inexpensive and efficient device. In particular, a power recovery device from hot water has been a hindrance to practical use because of the large size of the device, but the fact that a compact condenser with high efficiency was obtained by the present invention is such a power source. It can greatly contribute to the improvement of the recovery device.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an example of a condenser according to the present invention, FIG. 2 is an enlarged cross-sectional view taken along the line AA in which a part of FIG. 1 is broken, and FIGS. ) Is a configuration diagram of a bubble generating plate, (a) is a front view, (b) is a plan view, (c) is a side view, and FIG. 4 is a schematic cross-sectional view showing an embodiment of a heat cycle device according to the present invention. FIG. 5 is a schematic sectional view showing an example using another evaporator in the heat cycle apparatus of FIG. 4, FIG. 6 is a schematic sectional view showing an embodiment of a power recovery heat cycle apparatus according to the present invention, FIG. 7 is a schematic sectional view showing a preferred example of the evaporator in FIG. 1 ... Condenser body, 4 ... Condensing chamber, 6 ... Heat transfer tube, 7 ... Gas inlet, 10 ... Liquid filled in the condensation chamber, 15 ... Bubbling plate, 16 ... Air supply chamber , 17 ... Cooling water, 20 ... Bubbles of gas to be condensed, 22 ... Evaporator, 23 ... Liquid piping, 24 ... Pump, 25
...... Throttle valve, 26 ...... High pressure piping, 33 ...... Hot water tank, 35 ...... Heat exchange coil, 36 ...... Chamber type evaporator.

Claims (6)

[Claims] 1. A condenser in which a gas to be condensed is introduced to condense the gas into a condensing chamber having a plurality of heat transfer tubes through which a cooling fluid flows, and the heat is transferred to the condensing chamber. A direct contact type condenser characterized in that a bubble generating means for filling a liquid cooled by a heat pipe and introducing a gas to be condensed into the filled liquid in the form of bubbles is provided at the bottom of the condensation chamber. 2. The direct contact condenser according to claim 1, wherein the filling liquid is the same substance as the gas to be condensed. 3. A liquid heating medium is forcibly circulated between an evaporator and a condenser arranged in a closed piping system, and a gaseous heat medium vaporized by the evaporator is liquefied by the condenser. In a heat cycle device in which the heat medium is circulated to the evaporator again, the condenser comprises a shell-and-tube heat exchanger in which a large number of tubes are laterally arranged in a shell. The heat medium is passed to the shell side of the vessel and the heat radiation fluid is passed to the tube side to form a condensing chamber in the shell, and the heat medium is in a liquid state in the condensing chamber and the tube wall of the tube is formed. A gas heat medium introduction means for introducing the gas heat medium vaporized in the evaporator in the form of bubbles into the lower part of the liquid layer filled in the condensation chamber so as to cover substantially all of the surface. Is provided from the liquid layer position above the means. A heat cycle device, wherein a liquid heat medium outlet for discharging a part of the liquid toward the evaporator is provided in the condensing chamber. 4. The heat cycle device according to claim 3, wherein the heat medium is Freon or ammonia. 5. The heat cycle apparatus according to claim 3, wherein a power recovery turbine is arranged in a gas heat medium passage extending from the evaporator to the condenser. 6. The thermal cycler according to claim 5, wherein the evaporator is immersed in a hot water tank.