JP2530221B2 - Waste heat recovery type heat storage cooling system - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an absorption type cooling system, and in particular, when collecting waste heat and cooling the waste heat where a waste heat generation location and a cooling heat requirement location are remote locations. The present invention relates to a suitable waste heat recovery type heat storage cooling system.

[Conventional technology]

As shown in FIG. 6, a conventional waste heat recovery type absorption refrigeration system is constituted by connecting a waste heat source and a regenerator of an absorption chiller with a heat pipe, and receives heat from the waste heat to regenerate the absorption liquid ( It was used as a heat source. However, equipment that produces high-temperature waste heat (eg, kilns for kilns, various furnaces in steelworks, etc.)
In general, continuous operation is performed day and night from the viewpoint of improving thermal efficiency. On the other hand, the time required to cool the living room such as the office of the factory is usually only during the daytime.

Therefore, the heat source from the heat pipe necessary for the absorption liquid regeneration of the absorption refrigeration material, that is, the factory waste heat can be used only in the daytime, and is exhausted without recovering the heat at night. Had to be reduced.

On the other hand, Japanese Patent Laid-Open No. 61-180891 discloses the principle of concentration difference heat storage, but since it is an adiabatic operation in which heat storage and heat dissipation are alternately repeated, a heating source is required only during heat storage, and as described above. It is not applicable when heat is continuously generated.

[Problems to be Solved by the Invention]

The above-mentioned conventional technology does not consider the positional relationship between the heat source system and the heat utilization system and the difference in the operating time, and there is a problem in terms of improving the heat recovery rate, such as when the waste heat generation location and the cold heat requirement location are different. there were.

The object of the present invention is to significantly improve the heat recovery rate by providing a heat storage function by paying attention to the difference between the positional relationship and the operating time described above, and at the same time, it is possible to minimize the size of each element device, An object of the present invention is to provide a waste heat recovery type heat storage cooling system using a heat pipe in which a regenerator is installed at a waste heat generation place and a heat loss does not occur even if a cold heat generation unit is arranged at a remote place from the place.

[Means for solving the problem]

The above-mentioned purpose is in a waste heat recovery heat storage type cooling system,
Storage is provided separately for the absorption liquid regenerator, which uses the waste heat to concentrate the condensed liquid and the water that is generated and condensed when it is condensed, separately from the absorption liquid regenerator, and to absorb water vapor. This is achieved by providing the section and the radiator at the required cooling point.

That is, the present invention comprises a waste heat recovery unit, an absorption liquid regeneration unit, a water vapor absorption unit, a radiator, an absorption liquid storage tank, and a refrigerant water tank, and the heat recovered by the waste heat recovery unit is used to regenerate the absorption liquid. In the waste heat recovery type heat storage cooling system, the waste heat recovery unit, the absorption liquid regeneration unit,
An absorption liquid storage tank and a refrigerant water tank are installed, a steam absorption unit and a radiator are installed in a remote place where cold heat is required, and the waste heat is used to concentrate and concentrate the absorption liquid in the absorption liquid regeneration unit. The absorbed absorption liquid is stored in an absorption liquid storage tank, and the concentrated absorption liquid is transported to a place where cooling is required, and the concentrated absorption liquid is introduced into the steam absorbing section and the radiator installed there to generate cold heat. The feature is a waste heat recovery type heat storage cooling system.

The present invention will be described in more detail. Examples of the apparatus used in the system of the present invention include a storage tank for storing a concentrated absorption liquid, a water tank for storing condensed condensate, and a waste heat recovery device for concentrating the absorption liquid. An absorbent regenerator consisting of a regenerator having a heat pipe connected to it and a condenser for condensing the generated water vapor; an evaporator for evaporating water and an absorber for absorbing the water vapor generated by the absorbent. It is composed of a water vapor absorbing part, an absorbing liquid pipe and a transportation means which respectively connect the storage tank and the absorbing liquid regenerating part, or the water vapor absorbing part.

In the present invention, the absorbent regenerator and the water vapor absorber are separately provided separately, and the absorbent regenerator is installed in the vicinity where waste heat can be used to reduce heat loss. Will be installed near the area where cooling is required, that is, near offices that require cooling.

Further, the absorbent regenerator can be connected to each concentrator and the waste heat recovery unit as a plurality of heat pipes in a plurality of stages, while the water vapor absorber can be installed in a plurality of stages.
It is also possible to perform a heat exchange in the descending order of the temperature of the generated cold heat to take out the cold heat.

[Work]

The heat pipe that connects the waste heat part and the absorbent regenerator for concentrating the absorbent, transfers the heat from the waste heat part to the regenerator of the absorbent regenerator, and heats the absorbent via the heat transfer surface. Generate water vapor and concentrate the absorption liquid. The generated steam moves to the condensation chamber where it is condensed and condensed.

The concentrated absorption liquid flows into the storage tank, and the condensed water flows into the water tank for storage. The stored absorption liquid and water are taken out of the storage tank as needed, transported, and sent to the absorber of the water vapor absorption unit at a remote place, and the absorption liquid and water are cooled by the heat exchanger. The pressure in the absorption section is reduced, the water sprinkled in the evaporator is evaporated, and the latent heat is removed to lower the temperature. The cold heat is taken out through the heat exchanger and serves as a cooling source.

With such a configuration, first, since the absorbing liquid storage tank and the water tank are provided, waste heat can be continuously recovered, and thermal energy can be converted into a concentration difference and stored. Furthermore, assuming that the cooling time is half a day (12 hours), it is possible to make it twice the amount of heat recovered from the cooling output and waste heat. Secondly, since the absorbent regenerating unit and the water vapor absorbing unit are separately arranged, it is possible to separately install the absorbing liquid regenerating unit and the water vapor absorbing unit, and the following effects are produced. That is, it is located far away from the factory device, which is a heat generating portion in a normal usage mode, and a place where cooling is required, for example, a living room such as an office. This may be achieved by some method of transporting high-temperature heat to the cold heat generating section or conversely, transporting the cold heat generated to the living room, but in either method, the heat is not transferred by the conventional heat transfer technology. Although the loss was extremely large, there was a problem. However, according to the present invention, the heat is transported by transferring the liquids having different concentration differences from the heat source side to the cold heat generating section side, and no heat loss occurs.

〔Example〕

Examples of the present invention will be described below with reference to the drawings, but the present invention is not limited to these examples.

Embodiment 1 An embodiment of the present invention will be described with reference to FIG.

FIG. 1 is a basic system diagram which is the basis of the present invention.
Reference numeral 1 is a waste heat recovery device, 2 is an absorption liquid regenerator comprising a dilute absorption liquid concentrator 21 and a condenser 22 separated by a partition wall 26, 3
Is an absorption liquid storage tank for storing the concentrated liquid of the absorbing liquid in the lower part and the dilute liquid in the upper part with a specific gravity difference, and 4 is a partition wall 46 for partitioning the water vaporizer 42 and the absorber for absorbing the generated water vapor in the concentrated medium.
41 is a water vapor absorbing section, 5 is a water tank for storing the water condensed and condensed by the water vapor evaporated from the lean absorbent, 6
Is a heat exchanger for the concentrated and dilute absorbents, and 7 is a radiator.

Further, the water vapor absorption unit 4 described above is provided with the pipes 111 and 112,
It is separated from each part by 113 and 115, 120 and 121, the heat source system and the cold heat generation system are installed remotely, and this system is formed by connecting the pipes of the above-mentioned location at the transfer destination. It

The operating conditions of the above system configuration will be described below.

The high temperature waste heat 1000 is introduced into the waste heat recovery unit 1, heats the heat receiving end 11 of the heat pipe 10, lowers the temperature, and is discharged from the pipe (chimney) 2000 to the outside. The heat received at the heat receiving end 11 is a heat pipe
It travels along 10 and moves to the heat dissipation end 23.

The condenser 102 of the absorbent regenerator 2 has a pipe 102 and a spray nozzle 25.
The diluted absorbing liquid supplied via the above is sprayed onto the heat radiating end 23 of the heat pipe described above and heated to generate water vapor.
The generated steam is a heat transfer tube 24 introduced by a tube 107,
It is cooled by the cooling water discharged through the pipe 108, condensed, and flows into the water tank 5 through the pipe 106 for storage.
The absorption liquid concentrated by evaporation is recirculated through the pipe 103, most of it through the pipe 104, and the rest is introduced into the lower layer of the absorption liquid storage layer 3 through the heat exchanger 6 and the pipe 105. The upper layer of the absorbent storage layer 3 stores the diluted absorbent and is introduced into the heat exchanger 6 through the pipe 101. In the heat exchanger 6, the temperature is increased by exchanging heat with the concentrated absorbent having a high temperature as described above, and the above-described flow is performed through the pipe 102.

The above is the operation of concentrating the lean absorbent by the waste heat recovery heat source and separating and storing it into the concentrated absorbent and water.

Next, the operation of generating cooling by using the concentrated absorbent and water will be described.

The concentrated absorbing liquid is drawn out from the lower layer of the storage tank 3 by a pipe 111 and transferred, and is sprayed by a pipe 112 and a spraying nozzle 45 onto a cooling heat transfer pipe 43 arranged in the absorber 41 of the water vapor absorbing section 4. At this time, as will be described later, the pressure of the water vapor absorption section 4 decreases. On the other hand, the water drawn from the water tank 5 is pipe 12
It is sprayed on the heat transfer tube 44 of the evaporator 42 through the spray nozzles 47 through 0, 121 and 122, and the sprayed water is evaporated due to the above-mentioned internal pressure drop. At this time, the latent heat of vaporization is removed and the temperature drops.
1 flows to the heat transfer tube 44, heats the sprayed water described above, cools itself, is withdrawn from the tube 132 and is recirculated to the cooler 7, and while flowing through the heat transfer tube 71, is blown indoors by the fan 72. The temperature is lowered by exchanging heat with air.

The water vapor generated in the evaporator 42 flows to the absorber 41, while the non-evaporated water is recirculated by the pipe 123.

The water vapor introduced into the absorber 41 is absorbed by the above-mentioned concentrated absorbing liquid, the absorbing liquid is diluted and recirculated by the pipes 113 and 114, and the rest is transferred and merges with the pipe 101 via the pipe 115, and The section returns to the upper layer of the storage tank 3 by the pipe 116.

The above is the description relating to the cold heat generating operation, and a quantitative description will be given below together with FIG.

FIG. 2 shows the temperature and water vapor characteristics of the absorbing liquid suitable for the cycle of the present invention, using the concentration as a parameter.

In FIG. 1, the lean absorbent is introduced into the concentrator 21 of the absorbent regenerator 2 from which the non-condensed residual gas has been extracted. In this case, the heating temperature of the absorbing liquid is 100 ° C. (the heat input amount per unit time is 1), and the condensation temperature of the steam cooled by the heat transfer tube 24 of the condenser 22 is 40 ° C. (cooling heat amount of about 1). At that time, the concentration of the absorbing solution is about 66% (point A in the figure) and the temperature is 100 ° C. This concentrated liquid is used in the heat exchanger 6 to dilute the absorbent (at room temperature, 30
The temperature is changed to 42 ° C. (temperature efficiency is 80%) to be stored in the lower layer of the storage tank 3. This operation is 24
The total heat input is 24 because it is carried out continuously over time.

On the other hand, in the cold heat generation operation, the temperature at which the concentrated absorbing liquid is cooled in the heat transfer tube 43 of the water vapor absorbing portion 4 from which the non-condensing gas has been extracted is 42 ° C., the cooling heat amount per unit time is 2, and the dilute absorbing liquid When the concentration is 60%, the internal pressure of the water vapor absorption part 4 is 6mmH.
It is about g and about 7 from the intersection B with water in Fig. 2.
Water evaporates at ° C. This water and the water introduced from the pipe 131 are heat-exchanged by the heat exchanger 44, the temperature is lowered, and the water is extracted from the pipe 132. The cooler 7 exchanges heat with the indoor air to be used for cooling. This heat radiation amount is about 2, and the total heat radiation amount is 2 × 12 = 24 after 12 hours of operation.

Therefore, by operating the total heat input for 12 hours, all the heat can be released.

As described above, according to the present invention, by installing the absorbing liquid storage tank, a system for recovering waste heat for 24 hours by continuous operation during the day and night and completing cooling operation for only 12 hours during the day is completed, and absorption at night. The concentrated absorption liquid is stored by using waste heat exclusively for liquid regeneration (concentration), and the absorption liquid is regenerated by using the waste heat during the daytime and stored in the storage tank, while on the other hand, the concentrated absorption liquid is absorbed from the absorption liquid storage tank. The liquid can be drawn out and introduced into the water vapor absorption section to generate cold heat. Therefore, it has a feature that it can generate a quantity of cold heat twice as much as the quantity of waste heat per unit time, and separates the waste heat recovery part and the water vapor absorption part and separately connects them by a transportation means. ,
It is possible to install the heat recovery unit in the vicinity of the waste heat source and install the cold heat generation unit in the cold heat demand place. And the heat transfer between the two is because the absorbing liquid with different concentration moves,
It is completely independent of temperature and has a very outstanding feature that no heat loss occurs.

Embodiment 2 Another embodiment of the present invention will be described with reference to FIGS. 3 and 4. FIG. 3 shows that the absorption liquid regenerating section 2 has two stages, and the heat pipes 10a and 10b capable of heat recovery corresponding to the absorption section also have two series, and means for more effectively utilizing waste heat and a corrosive environment of constituent materials. It was made for the purpose of mitigation. Further, as shown in FIG. 3, the water vapor absorption section 4 is provided in two stages, so that the concentration of the diluted absorbent after absorption can be further lowered.

 The operation of the other components is the same as in FIG.

FIG. 5 is a graph showing the relationship between the concentration change rate δ and the heat storage density φ. That is, as shown in FIG. 5, by increasing the variation range of the concentration of the absorbing liquid, the heat storage amount per unit weight of the absorbing liquid can be increased, and the volume of the storage tank 3 can be reduced accordingly.

In the embodiment shown in FIG. 3, both the absorbing liquid regenerating section 2 and the water vapor absorbing section 4 are shown as two stages, but a device having either one of them as two stages is naturally included in the present invention, and each section is divided into two stages. The number of stages is not limited, and a plurality of stages is also within the scope of the present invention.

FIG. 4 shows an operation diagram when both of the above-mentioned two stages are used. The absorption liquid heating temperature in the second stage 2b of the absorption liquid regeneration section 2 is 110 ° C. and the condensation temperature is 52 ° C. At this time (point A in Fig. 4), an absorption liquid concentration of 66% was obtained, and the storage tank 3
The temperature of the absorption liquid heating in the first stage 2a is increased to 105
When the condensing temperature is 60 ° C. and the condensing temperature is 60 ° C. (point B in FIG. 4), the absorption liquid concentration is 60%. Next, in the water vapor absorbing section 4, the first stage
When the absorption liquid is held at 40 ° C in both 4a and the second stage 4b, the concentration of the absorption liquid is 60% in the first stage 4a, the evaporation temperature is 4 ° C (point C in the figure), and 54% in the second stage 4b. C (point D in the figure) is obtained.

Therefore, the variation range of the absorption liquid concentration is 12%, which is twice the 6% shown in FIG. As shown in FIG. 5, the heat storage density with respect to the range of concentration change is C _{1 in the} embodiment shown in FIG.
= 60%, C ₂ = 66%, the value on the horizontal axis δ is 10, and the heat storage density φ at that time is 54 kcal / kg, whereas in the embodiment shown in FIG. 4, C ₁ = 50%, C ₂ = 66%, δ = 26, φ = 110 kcal / kg. Therefore, the heat storage density has been doubled, and the absorption liquid storage tank for storing the same amount of heat has been halved, enabling a significant reduction in size.

〔The invention's effect〕

As described above, according to the present invention, by providing the heat storage tank, it is possible to arbitrarily select the operating time of the heat source system and the operating time and place of the cold heat system, and to provide a system suitable for recovering the waste heat from the factory with the heat pipe. it can. Especially, when using the factory waste heat of 24-hour operation, if the cooling time is set to 12 hours, it has the effect that the cold heat output of twice the amount of waste heat per unit time can be obtained, and the absorption liquid regenerator is half of the conventional one. There is an effect that the size can be reduced. Furthermore, the effect of the present invention is that the absorption liquid regeneration unit and the water vapor absorption unit are separately arranged, so that the absorption regeneration unit can be installed close to the heat source system, and the length of the heat pipe can be shortened, and the water vapor absorption unit can be shortened. Can be installed in a cold heat demand place, and heat can be transported between the two by transferring an absorbing liquid, which has the effect of completely preventing the heat loss seen in the conventional example.

[Brief description of drawings]

FIG. 1 is a basic system diagram of a waste heat recovery type heat storage cooling system according to the present invention, FIG. 2 is an operation diagram in the system of FIG. 1, and FIG. 3 is a system diagram showing another embodiment of the present invention. , Fig. 4 is an operation diagram in the system of Fig. 3, Fig. 5 is a graph showing the relationship between the absorption liquid concentration change width and the heat storage density, and Fig. 6 is a waste heat recovery type cooling system seen in a conventional example. FIG. 1 ... Waste heat recovery device, 2 ... Absorbing liquid regeneration part, 3 ... Absorbing liquid storage tank, 4 ... Water vapor absorbing part, 5 ... Water tank, 6 ... Heat exchanger, 7 ... Radiator, 10 ... … Heat pipe, 1000 …… Waste heat source

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Ozeki 4026 Kuji Town, Hitachi City, Hitachi, Ibaraki Prefecture Hitachi Research Laboratory Ltd. (72) Hideaki Kurokawa 4026 Kuji Town, Hitachi City, Ibaraki Hitachi Research Laboratory, Hitachi Ltd. In-house (72) Inventor Yasukichi Takahashi 4026 Kuji-cho, Hitachi-shi, Ibaraki Hitachi Research Laboratory, Hitachi, Ltd. (56) Reference JP-A-55-14416 (JP, A)

Claims (1)

(57) [Claims] 1. A waste heat recovery unit, an absorption liquid regeneration unit, a water vapor absorption unit, a radiator, an absorption liquid storage tank, and a refrigerant water tank, wherein the heat recovered by the waste heat recovery unit is used to regenerate the absorption liquid. In a waste heat recovery type heat storage cooling system, a waste heat recovery unit, an absorption liquid regeneration unit, an absorption liquid storage tank and a refrigerant water tank are installed near the place where waste heat can be used, and a steam absorption unit is installed in a remote place where cold heat is required. Install a radiator,
The waste liquid is used to concentrate the absorption liquid in the absorption liquid regeneration unit, the concentrated absorption liquid is stored in the absorption liquid storage tank, and the concentrated absorption liquid is transported to the cold heat-required area, and the water vapor absorption unit installed there. And a waste heat recovery type heat storage cooling system which introduces the concentrated absorbent into a radiator to generate cold heat.