KR101511051B1 - Refrigerator for district cooling system - Google Patents

Abstract

This invention is related to a refrigerator in a district cooling system that can improve the efficiency of renewable energy power generation systems while directly using district heating water of high temperature and high pressure and efficiently use surplus power in a combined-cycle thermal power plant to overcome the inefficiencies of a conventional absorption and dehumidification-type refrigerating unit which has an indirect heat exchange method generally applied to a conventional district cooling system. In particular, the refrigerator in the district cooling system can produce cold water using the evaporative latent heat needed for spray-evaporating the pressurized hot water provided through regional hot and cold water suppliers under lower pressure than the atmosphere while generating hot water from the condensed latent heat and sensible heat of steam of the evaporated pressurized hot water. The refrigerator can also improve the inefficiencies in energy use and energy supply-demand discordance by taking advantage of the surplus power of combined-cycle thermal power plants as driving power source.

Description

[0001] The present invention relates to a refrigerator for district cooling system,

[0001] The present invention relates to a refrigerator for a district cooling system and, in order to overcome the disadvantage of low efficiency due to an indirect heat exchange system of an absorption and dehumidification refrigerator generally used in a conventional district cooling system, And more particularly, to a refrigerator for a local cooling system which can utilize a surplus power of a cogeneration power generation system in a high efficiency.

Generally, the district cooling system is a system that indirectly exchanges hot water supplied through the district heating pipe network to a large-sized customer and uses it as a heat source necessary for the operation of the absorption type refrigerator or the wet type freezer, thereby supplying cold or cold water to the user collectively .

In some cases, the system may consist of a system that collectively produces cold water from a local heating and heating source itself, and then supplies the cold water to the user through a separate cold water piping. In the method of producing cold water by using waste heat from a local heating / In terms of the fact that the air conditioner is generally applied, there is a difference in the place where the cold water is produced, whether it is the local heating / heating source or the consumer, but the basic structure is not so different.

The conventional technology for the refrigerator using the hot water supplied from the local heating and cooling source is disclosed in Korean Patent Application No. 2007-0039160 entitled " Absorption refrigerator for hot water "and Korean patent application No. 2009-0072013 for" And the like.

However, although the efficiency of the absorption chiller, that is, the coefficient of performance called COP (coefficient cf performance) is somewhat different depending on the system, for example, a system of one- or two- Efficiency.

Since the coefficient of performance of this absorption type refrigerator is greatly inferior to that of an electric driving heat pump (EHP) which is a competitive system, which is an average coefficient of 3.5 to 4.0, it is inferior in market competitiveness such as economical efficiency It is difficult to secure a market for the cooling sector, which is a major demand source of waste heat in the summer cogeneration power generation.

In addition, considering the whole energy use efficiency in a year, the demand for heating is greatly lowered in the summer, so the operation loss of the cogeneration facilities is stopped due to economical efficiency.

Therefore, in order to strengthen the competitiveness of the district heating and air-conditioning business by expanding potential new users as well as to a large number of users connected to the piping network of the district heating and cooling system, and furthermore, as an alternative to reduce the electricity demand in the summer, There is a strong demand for the development of an efficient local cooling system.

Korean Patent Application No. 2007-0039160 Korean Patent Application No. 2009-0072013

It is an object of the present invention to provide a refrigerator for a competitive district cooling system by improving the low efficiency of a conventional refrigerator using hot water supplied from a local heating / heating source.

It is another object of the present invention to provide a refrigerator for a local cooling system that can effectively combine the characteristics of a renewable energy source generated intermittently according to external environmental conditions.

 The present invention relates to a refrigerator for a district cooling system that produces cold water for cooling by using compressed hot water supplied from a supply pipe of a district heating and cooling source, And an evaporation chamber for evaporating the evaporated water vapor and discharging the evaporated water vapor through an exhaust pump, and a cooling water supply unit for supplying cooling water for cooling through the heat exchange tube installed inside the evaporation chamber, A cold water storage tank for collecting and storing cold water for cooling having a lowered temperature by supplying hot water to the evaporation chamber, and a heat exchanger for exchanging the water vapor discharged from the evaporation chamber with the water supplied from the outside to condense the water vapor, And the temperature of the water is increased, and the heat exchange A heat exchanger for discharging condensed water of the finished water and steam; And a water storage tank for collecting and storing the condensed water of the water and the steam having been heat-exchanged.

In the evaporation chamber, the compressed hot water may be supplied to the lower end of the evaporation chamber and sprayed upward toward the heat exchange tube.

According to an embodiment of the present invention, the upper open shell is disposed apart from the heat exchange tube, and the compressed hot water is injected through the nozzle disposed through the through hole formed in the bottom of the shell.

An annular space is formed between the nozzle and the through hole to drain the condensed water of the compressed hot water partially condensed around the heat exchange tube.

In addition, a blowing means for forming an upward flow through the outer surface of the shell and the annular space and along the outer surface of the heat exchange tube may be provided at a lower portion of the shell.

In addition, a distribution means for branching the compressed hot water injected from the nozzle to both sides may be provided on the outer side of the heat exchange tube located in the upper right room of the nozzle.

In addition, a cooling fin may be provided in an area of the outer surface of the heat exchange tube where at least the compressed hot water injected from the nozzle is evaporated.

The condensed water of the compressed hot water drained to the lower portion of the evaporation chamber may be recovered to the sequential storage tank through a drain line provided in the evaporation chamber.

According to an embodiment of the present invention, the evaporation chamber may further include a vacuum pump capable of forming atmospheric pressure in the evaporation chamber below atmospheric pressure.

In particular, the vacuum pump may be selectively and intermittently driven, wherein the driving power of the vacuum pump is preferably surplus power of a renewable energy generation source or cogeneration power generation.

Further, in the embodiment of the present invention, it is possible to further include time compensating means for supplying a positive time corresponding to the flow rate of the compressed hot water injected into the evaporation chamber to the recovery pipe of the local heating / heating heat source.

The time compensating means calculates the flow rate of the compressed hot water injected into the evaporation chamber by the first flow meter provided on the evaporation chamber supply line of the compressed hot water and supplies the time to the recovery pipe of the local heating / And controls the flow rate of the time measured by the second flow meter installed on the compensation line to correspond to the flow rate of the compressed hot water calculated by the first flow meter.

Preferably, the time compensating means includes a pressurizing pump for pressurizing the water supplied to the recovery pipe of the local heating / heating heat source.

The present invention makes it possible to achieve an improved cooling efficiency compared to the existing district cooling system by using the characteristics of water, which is the greatest latent heat of evaporation, and the characteristics of the local cooling and heating piping network, which is transferred to the compressed hot water of high temperature and high pressure, The heat energy of evaporated water vapor can be recovered and reused as a heat source of a conventional absorption refrigerator in which hot water supply or additional installation operation can be performed. Therefore, the overall efficiency of the system can be improved greatly compared to a local cooling system based on the conventional indirect heat exchange type absorption refrigerator- There is an effect that can be improved.

The present invention also provides a refrigerator for a district cooling system suitable for the characteristics of a new and renewable energy generation source, which is generated intermittently in terms of utilization of a new and renewable energy generation source. By providing effective utilization means of a renewable energy generation source, It has the advantage of reducing energy usage and contributing greatly to the reduction of greenhouse gas emissions.

In addition, by providing a freezer for a district cooling system that can effectively utilize not only the winter season but also the waste heat generated in the summer season, it can greatly improve the operability of the annual district heating and cooling system and make it possible to construct a competitive district heating and cooling system.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view schematically showing a general configuration of a refrigerator for a local cooling system according to the present invention; FIG.
Figure 2 is a phase diagram of water to illustrate that compressed hot water supplied from a local cooling and heating source is evaporated in a vaporization chamber.
3 schematically shows the internal structure of the evaporation chamber;
FIG. 4 is a cross-sectional view showing a detailed structure of a heat exchanging tube around the evaporation chamber; FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing the embodiments of the present invention, a description of well-known structures that can be understood by those skilled in the art will be omitted so as not to obscure the gist of the present invention. In addition, when referring to the drawings, it should be considered that the thicknesses of the lines and the sizes of the constituent elements shown in the drawings may be exaggerated for clarity and convenience of explanation.

First, a general configuration of a refrigerator 10 for a local cooling system according to the present invention will be described with reference to FIG.

The present invention relates to a refrigerator (10) for a district cooling system which produces cold water (R) for cooling using compressed hot water (P) supplied from a supply pipe (2) of a local heating / (P), which is naturally generated when the compressed hot water (P) supplied from the compressor (2) is injected under the atmospheric pressure of atmospheric pressure or less in the evaporation chamber (100) Thereby forming a cool air atmosphere.

That is, the compressed hot water P supplied from the supply piping 2 of the local heating / heating source 1 has a pressure and a temperature of about 16 bar / 115 캜, and the compressed hot water P having such a pressure / The boiling point of the compressed hot water P is naturally generated because the boiling point of the compressed hot water P is less than 100 ° C under the pressure condition inside the evaporating chamber 100.

The evaporation phenomenon of the compressed hot water P is more easily understood with reference to the phase equilibrium diagram of the water shown in FIG. 2. The point "A" shown in the phase balance diagram of FIG. 2 is a compression hot water having a condition of 16 bar / (P) is present as water (liquid). When the compressed hot water P is injected into the evaporation chamber 100, the pressure is instantaneously lowered to the atmospheric pressure before sufficient heat transfer occurs, so that it is moved to the state of "B" point, that is, the equilibrium state of the water vapor Evaporation occurs. In this process, the heat corresponding to the latent heat of evaporation is absorbed from the surroundings and the temperature is lowered.

If the pressure in the evaporation chamber 100 is maintained at "C " below the atmospheric pressure, evaporation of more active compressed hot water (P) will occur, as will be described in more detail in that section.

Meanwhile, the evaporation of the compressed hot water P in the evaporation chamber 100 occurs instantaneously due to the pressure and temperature conditions. The compressed hot water P is injected into the nozzle 116 to make fine droplets, thereby increasing the evaporation surface area .

In addition, if the water vapor of the compressed hot water P which has been sprayed and evaporated first is quickly removed, then the compressed hot water P to be sprayed subsequently is not evaporated most of the evaporation heat from the atmospheric (air in the evaporation chamber) Latent heat is obtained and effective cooling of the atmosphere can be achieved.

In order to achieve this, in the present invention, the compressed hot water P is supplied to the lower end of the evaporation chamber 100 to be sprayed upward in the direction toward the heat exchange tube 110, so that the evaporated steam passes through the injection pressure at the nozzle 116, So that it is naturally collected at the upper part of the evaporation chamber 100. [0064] Accordingly, the present invention provides an exhaust pump 120 at an upper portion of the evaporation chamber 100 to rapidly discharge steam.

3, the water vapor is supplied to the lower portion of the evaporation chamber 100, particularly, the lower portion of the nozzle 116 through which the compressed hot water P is injected, It is also possible to form a strong ascending air stream which collects on the upper portion of the nozzle 100 to increase the discharge speed of the water vapor, thereby rapidly removing the water vapor around the nozzle 116 to further enhance the cooling efficiency of the atmosphere.

In the evaporation chamber 100 having the above-described structure, a heat exchange tube 110 is installed, and cold water R for cooling supplied from the cold water storage tank 200 flows into the heat exchange tube 110.

The heat exchange tube 110 is preferably located adjacent to the nozzle 116 and is preferably in the region where the compressed hot water P ejected from the nozzle 116 evaporates, The temperature of the cold water for cooling R is lowered due to the heat exchange between the cooled air and the cold water for cooling R in the heat exchange tube 110 in the process of obtaining the latent heat of vaporization from the surrounding atmosphere.

When the circulation process of the cold water for cooling R is repeated, the temperature of the cold water for cooling R is stored in the evaporator chamber 100 And the cold water for cooling R having a lowered temperature is supplied to a known fan coil cooler or the like to be used for indoor cooling.

1 does not show the pump means for circulating the cold water for cooling R but it will be apparent to those skilled in the art that the pump means for providing the circulating power of the cold water for cooling R will be provided I will do it.

4 shows an embodiment of the structure of the nozzle 116 and the heat exchange tube 110 for spraying the compressed hot water P. In FIG.

The cooling water for cooling R in the present invention is largely achieved by heat exchange with the atmospheric temperature by supplying the latent heat of vaporization to the compressed hot water P so that the heat exchange tubes 110 It is preferable to induce the evaporation of the compressed hot water P mainly to occur.

Fig. 4 is a sectional view cut on the basis of the position of the nozzle 116, showing one embodiment configured for this purpose. Here, FIG. 4 is a cross-sectional view based on one nozzle 116. Therefore, it is to be understood that, when a plurality of nozzles 116 are installed, the same structure as shown in FIG.

4 is characterized in that a shell 112 having a semicircular cross-sectional shape opened at an upper portion is spaced apart from the lower portion of the heat exchange tube 110 and a through hole 114 formed in the bottom of the shell 112, So that the nozzle 116 is disposed.

Here, condensed water (C) of condensed hot water (P) condensed in the vicinity of the heat exchange tube (110) can be drained between the nozzle (116) and the through hole (114) An annular space 115 through which the upward flow generated by the blowing means 130 can pass to the heat exchange tube 110 is formed.

The compressed hot water P injected with fine droplets in the nozzle 116 is evaporated by the pressure / temperature conditions inside the evaporation chamber 100. The most ideal evaporation mode in the present invention is that the droplet gets a latent heat of evaporation from the surrounding atmosphere It will lower the ambient temperature. However, if there is a difference in the evaporation rate between droplets due to the difference in size of the droplet, that is, the difference in surface area, the droplet that is evaporated later acquires a latent heat of evaporation from the droplet at a close distance or the water vapor of the first evaporated droplet The cooling effect of the atmosphere is lower than expected, and condensation water is generated in this process.

Considering the above evaporation mechanism, it is very difficult to completely remove the generation of condensed water, but it is necessary to minimize the generation of condensed water as much as possible. In order to achieve the above object, the present invention is characterized in that a region below the heat exchange tube (The atmospheric flow through the annular space) flowing within the confined region and facilitating rapid atomization and diffusion of the compressed hot water (P) droplets, rapid discharge of water vapor and raising the heat transfer coefficient The cooling effect of the atmosphere is maximized.

The water vapor outside the confined area of the shell 112 is collected in the upward flow of air flowing along the outer surface of the shell 112 and collected at the top of the evaporation chamber 100 and discharged to the outside by the exhaust pump 120.

4, the compressed hot water P sprayed from the nozzle 116 is uniformly supplied to both sides of the heat exchange tube 110 on the outer side of the heat exchange tube 110 located in the upper right chamber of the nozzle 116 A distribution means 118 serving as a branching structure can be provided to increase the effective area where substantial heat exchange takes place in the heat exchange tube 110. The cooling fin 111, which is a known construction for increasing the heat transfer effect, 110) outer surface.

Since the cooling of the heat exchanging tube 110, that is, the cooling of the cold water for cooling R will occur mainly in the space inside the casing 112, the cooling fin 111 can be installed in the heat exchange tube 110, The compressed hot water P sprayed from at least the nozzle 116 may be evaporated.

Meanwhile, in one embodiment of the present invention, the evaporation chamber 100 may further include a vacuum pump 150 capable of forming atmospheric pressure below the atmospheric pressure.

The refrigerator 10 for a local cooling system according to the present invention is not necessarily required to be in a vacuum state in which the pressure inside the evaporation chamber 100 is lower than atmospheric pressure. However, if the pressure in the evaporation chamber 100 is formed at a pressure lower than the atmospheric pressure, The cooling effect is doubled by rapid evaporation and discharge of steam due to the drop of the boiling point and the pressure difference.

In the present invention, the vacuum pump 150 for forming the inside of the evaporation chamber 100 at a sub-atmospheric pressure can be selectively and intermittently driven only when necessary in accordance with climatic conditions and cooling demand. In particular, 150, it is preferable to utilize surplus power of a renewable energy generation source or cogeneration power generation.

This is because one of the objects of the present invention is to provide a refrigerator 10 for a local cooling system that can replace an electric driven heat pump (EHP), which is a main cause of electric power shortage due to a surge in summer cooling demand, Power) is preferably not used.

The application of the vacuum state to the inside of the evaporation chamber 100 means that the surplus power generated by the intermittent and irregular renewable energy generation and cogeneration systems is stored and stored as vacuum energy, Therefore, it is advantageous that the utilization efficiency of the whole power generation system and the inefficiency due to the mismatch of demand and supply can be improved, and at the same time, the utilization of the renewable energy generation source can be greatly improved.

Particularly, when the solar power generation representative of the renewable energy generation source is combined as the driving power source 152 of the vacuum pump, the production efficiency and the cooling demand of the photovoltaic generation are timely and precisely matched.

What has been described above is the configuration of the evaporation chamber 100, which is the core of the present invention, and the remaining configuration will be described with reference to FIG.

In order to recover water vapor of the compressed hot water P evaporated in the evaporation chamber 100 at about 100 ° C, it must be condensed. Since the water vapor of the compressed hot water P has sufficient heat energy, it is preferable to recover the heat energy effectively. To this end, the present invention includes the heat exchanger 300.

The heat exchanger 300 condenses water vapor discharged from the evaporation chamber 100 and water W supplied from the outside to each other to condense water vapor and simultaneously supplies latent heat and sensible heat of steam to the water W, And discharges the heat exchanged water W and the condensed water C of the water vapor to the water storage tank 400.

The water W discharged from the heat exchanger 300 and the condensed water C of hot water are recovered and stored in the water storage tank 400. The hot water stored in the water storage tank 400 is supplied to the hot water tank, It can be utilized as a low-heat source of the absorption type refrigerator.

In addition, there is a condensed water (C) of the compressed hot water (P) drained to the lower portion of the evaporation chamber (100). That is, as described above, the compressed hot water P injected from the nozzle 116 can be partially condensed in the evaporation process. The condensed water C is collected by the gravity to the lower portion of the evaporation chamber 100, (400) through a drain line (140) provided at a lower portion of the heat exchanger (100).

In the embodiment of the present invention, the number of times W corresponding to the flow rate of the compressed hot water P injected into the evaporation chamber 100 is supplied to the recovery pipe 3 of the district heating / May further comprise compensation means (500). This is because it is desirable to keep the flow rate in order to prevent stable operation and vacuum generation in the piping network in the local heating and cooling pipe network.

The time compensating means 500 calculates the flow rate of the compressed hot water P injected into the evaporation chamber 100 through the first flow meter 510 installed on the evaporation chamber supply line ES of the compressed hot water P (W) measured by a second flow meter (520) installed on a time compensating line (WC) for supplying the water (W) to the recovery pipe (3) of the local cooling / heating heat source (1) (P) that is calculated by the heat pump (510). However, in the specification of the present invention, a detailed description of the well-known construction relating to the flow rate control will be omitted.

The time compensating means 500 may further include a pressurizing pump 522 for pressurizing the time W supplied to the recovery pipe 3 of the heat source 1 for the local heating and cooling. This is because the pressure in the recovery pipe 3 of the local heating / heating source 1 may vary in a range of about 3 to 6 bar, so that the pressure for injecting the water W into the recovery pipe 3 In order to prevent this, there may be a case where it is insufficient.

While the preferred embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles or spirit of the invention. Accordingly, the scope of the present invention will be determined by the appended claims and their equivalents.

1: Local heating and heating source
2: Supply piping 3: Recovery piping
10: Freezer for district cooling system
100: Evaporation chamber 110: Heat exchange tube
111: cooling pin 112: sheath
114: through hole 115: annular space
116: nozzle 118: dispensing means
120: exhaust pump 130: blowing means
140: Drain line 150: Vacuum pump
152: vacuum pump driving power supply 200: cold water storage tank
300: heat exchanger 400: water tank
500: time compensating means 510: first flow meter
520: second flow meter 522: pressure pump
ES: evaporation chamber supply line WC: time compensation line
P: Compressed hot water R: Cold water for cooling
W: Number C: Condensate

Claims (14)

The present invention relates to a refrigerator for a local cooling system that produces cold water for cooling by using compressed hot water supplied from a supply pipe of a local heating /
An evaporation chamber for evaporating the compressed hot water supplied from the supply pipe under an atmosphere pressure of atmospheric pressure or lower and discharging the evaporated steam through an exhaust pump;
A cold water storage tank for recovering cold water for cooling having a temperature lowered by supplying cold water for cooling through a heat exchange tube installed in the evaporation chamber and supplying latent heat to evaporate the compressed hot water in the atmosphere surrounding the heat exchange tube;
The evaporation chamber discharges heat from the externally supplied water to condense the water vapor. The latent heat and the sensible heat are supplied to the water to raise the temperature of the water, and the condensed water of the water and the steam, A heat exchanger for discharging; And
A water storage tank for collecting and storing condensed water of the water heat exchanged water and the heat exchanged water;
A refrigerator for a local cooling system. The method of claim 1, wherein in said evaporation chamber,
Wherein the compressed hot water is supplied to a lower end of the evaporation chamber and is sprayed in an upward direction toward the heat exchange tube. 3. The method of claim 2,
Wherein an outer shell opened upward along the outer side of the heat exchange tube is spaced apart and the compressed hot water is injected through a nozzle disposed through a through hole formed in a bottom surface of the shell. The method of claim 3,
Wherein an annular space is formed between the nozzle and the through hole so that condensed water of the compressed hot water condensed in the vicinity of the heat exchange tube can be drained. 5. The method of claim 4,
And a blowing means for forming an upward flow passing through the outer surface of the outer shell and the annular space and along the outer surface of the heat exchange tube is provided at a lower portion of the outer shell. The method of claim 3,
And a distributing means for distributing the compressed hot water injected from the nozzle to both sides of the heat exchanging tube located on the upper portion of the nozzle. 7. The method according to any one of claims 1 to 6,
Wherein a cooling fin is provided in an area of the outer surface of the heat exchange tube where at least the compressed hot water injected from the nozzle is evaporated. 5. The method of claim 4,
And condensed water of the compressed hot water drained to a lower portion of the evaporation chamber is recovered to the sequential storage tank through a drain line provided in the evaporation chamber. The method according to claim 1,
Wherein the evaporation chamber further comprises a vacuum pump capable of forming atmospheric pressure inside the evaporation chamber below atmospheric pressure. 10. The method of claim 9,
Wherein the vacuum pump is selectively and intermittently driven. 11. The method of claim 10,
Wherein the driving power of the vacuum pump is surplus power of a renewable energy generation source or a cogeneration power generation system. The method according to claim 1,
Further comprising time compensating means for supplying an amount of time corresponding to the flow rate of the compressed hot water injected into the evaporation chamber to the recovery pipe of the local heating / heating heat source. 13. The method of claim 12,
Wherein the time compensating means calculates a flow rate of the compressed hot water injected into the evaporation chamber by a first flowmeter provided on the evaporation chamber supply line of the compressed hot water and supplies a time compensation line to the recovery pipe of the local heating / Wherein the controller controls the flow rate of the water measured by the second flow meter installed on the first flow meter to correspond to the flow rate of the compressed hot water calculated by the first flow meter. 13. The method of claim 12,
Wherein the time compensating means comprises a pressurizing pump for pressurizing the time supplied to the return pipe of the local heating / heating heat source.

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