JPS6280459A - Absorption type heat pump - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a two-stage absorption heat pump for producing steam and the like for industrial processes.

[Conventional technology]

Fig. 5 shows a conventional absorption heat pump system, and in Fig. 5, 1 to 4 are shell A, respectively.
~Shell D. The shell A1 is composed of a generator 5 and a condenser 6. The generator 5 is provided with a heating heat exchanger 7, and the condenser 6 is provided with a cooling heat exchanger 8. The shell B2 serves as a first evaporator 9, in which there is a heat exchanger 10 for heating the refrigerant. Further, the shell C3 includes a second evaporator 11 and a first absorber 12.
It consists of Inside this shell C3, there is a heat exchanger tube 1
A large number of heat transfer tubes 3 are arranged, and the absorption liquid flows through the outside of the heat transfer tube 13, and the refrigerant flows through the inside, respectively, with the inside acting as the second evaporator 11 and the outside acting as the first absorber 12. . The shell D4 is the second absorber 14, and its structure is the same as that of the shell C3, in which a large number of heat transfer tubes 15 are arranged, water and steam supplied to the process flow inside the heat transfer tubes 15, and the heat transfer tubes 15 Absorption liquid flows outside. Shell A1 and shell D4 are connected by a concentrated solution tube 17 equipped with a solution pump 16, shell L) 4 and shell C3 are connected by an intermediate concentrated solution tube 18, and shell C3 and shell A1 are connected by a dilute solution tube 19. The solution flowing through the concentrated solution tube 17 and the dilute solution tube 19 is passed through the first heat recovery heat exchanger 20, and also through the intermediate concentrated solution tube 18 and the concentrated solution tube 17.
The solutions flowing through each undergo heat exchange in the second heat recovery heat exchanger 21. The condenser 6, the first evaporator 9, and the second evaporator 11 of the shell C3 are connected to refrigerant liquid pipes 22, 23, and a refrigerant pump 24 is installed in the middle. Further, the first evaporator 9 and the first absorber 12 are connected by a refrigerant vapor pipe 25, and the second evaporator 11 and the second absorber 14 are connected by a refrigerant vapor pipe 26. 27 is a process water pipe connected to the second absorber 14. Note that current control valves, on-off valves, etc. are omitted. Next, the operation will be explained. This absorption heat pump is always operated in a two-stage system, and the heat sources such as exhaust heat that serve as driving sources are the generator 5, the heat exchanger 7 for heating the first evaporator 9,
The hot steam that enters 10 and is supplied to the process is obtained from a second absorber 14. Further, the cooling water flows through the cooling heat exchanger 8 of the condenser 6. Due to the two-stage system operation, in the single-stage system, the first absorber J2 for heat output is operated as a heat source for the second evaporator 11. The flow of solution and refrigerant is shown below. The dilute solution returned to the generator 5 through the dilute solution tube 19 from the first absorber 12 of the shell C3 is heated by the heating heat exchanger 7 and releases the refrigerant as vapor. The released refrigerant vapor goes to the condenser 6, is cooled by the cooling heat exchanger 8, and after being condensed and liquefied, is passed through the refrigerant pump 24 through the refrigerant liquid pipes 22, 2g to the first evaporator 9 and Go to the second evaporator 11. In the first evaporator 9, the refrigerant liquid is heated by the heating heat exchanger 1°, and after evaporation, this refrigerant vapor is transferred to the refrigerant vapor pipe 25.
to the first absorber 12. On the other hand, the refrigerant is discharged from the generator 5, and the concentrated solution is passed through the concentrated solution pipe 17 by the solution pump 16 and
The heat recovery heat exchanger N20 and the second heat recovery heat exchanger 21 exchange heat with the high temperature solutions from the first absorber 12 and the second absorber 14, respectively, and the temperature increases and goes to the second absorber 14. The concentrated solution entering the second absorption w14 passes through the refrigerant vapor pipe 26 to the second evaporator 1 while flowing down the outer wall surface of the heat transfer tube 15.
The second absorber 14 absorbs high-pressure refrigerant vapor flowing from the second absorber 14 and generates heat at a high temperature. Due to this heat generation effect, the process water flowing through the heat transfer tube 15 is heated and becomes high-temperature hot water or steam, which is supplied to the process from the process water tube 27. The intermediate concentrated solution, whose concentration has become diluted by absorbing the refrigerant vapor, passes through the intermediate concentrated solution pipe 18 and goes from the second absorber 14 to the first absorber 12. On the way, the intermediate concentrated solution is converted into a concentrated solution by the heat recovery heat exchanger 2J. The temperature decreases due to heat exchange. In the first absorber 12, the intermediate concentrated solution tube flows down the outer peripheral wall of the heat transfer tube 13, and at this time absorbs the refrigerant vapor flowing from the first evaporator 9 through the refrigerant vapor tube 25. The condenser 6 flows through the heat transfer tube 13 due to the exothermic action accompanying this absorption.
The refrigerant liquid from the refrigerant vapor pipe 26 is heated and becomes vapor.
and goes to the second absorber 14. The absorption liquid, which has become a dilute solution by absorbing the refrigerant vapor, passes through the dilute solution pipe 19 and returns to the generator 15. During this process, heat is exchanged with the concentrated solution by the J-th heat recovery heat exchanger 20, and the temperature is lowered.

[Problems to be solved by the invention]

Since the conventional two-stage absorption type and two-stage pump equipment is configured as described above, only the two-stage system can be operated at all times, and the hot water/steam humidity for the process, the generator/first stage system, etc.
There is a drawback that operations such as switching between a two-stage system and a single-stage system cannot be performed depending on the temperature conditions of the heating medium for heating the evaporator. The present invention has been made to solve these problems, and its purpose is to provide an absorption heat pump that can be operated by switching between a single-stage system and a two-stage system.

[Means to solve the problem]

The absorption heat pump according to the present invention includes a bypass pipe connected to a first evaporator and a second evaporator, and a first refrigerant vapor pipe inserted into a refrigerant vapor pipe connected to the first evaporator, a first absorber, and a second absorber. and a second on-off valve, a third on-off valve inserted into the refrigerant vapor pipe between the first evaporator and the second absorber, and a fourth on-off valve inserted into the bypass pipe. .

[For use]

In this invention, during single-stage system operation, the solution returns to the generator from the generator through the second absorber, the fourth on-off valve, and the bypass pipe, and the refrigerant returns from the condenser to the first evaporator and second evaporator. It flows through the on-off valve to the second absorber.

【Example】

Embodiments of the absorption heat pump of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the configuration of one embodiment. In FIG. 1, numerals 1 to 27 are the same as those in the conventional apparatus described in 1. In this FIG. 1, the refrigerant vapor pipe 25 from the first evaporator 9 is
On the way, it branches into a refrigerant vapor pipe 28 going to the second absorber 14 and a refrigerant vapor pipe 29 going to the first absorber 2, and each pipe line is provided with on-off valves 30 and 31. Furthermore, an on-off valve 32 is also attached to the refrigerant vapor pipe 26 that connects the second evaporator 11 and the second absorber 14 . Intermediate concentrated solution pipe 8 and dilute solution pipe 19 from the second absorber 14
A bypass pipe 34 equipped with an on-off valve 33 is connected to the outlet side on-off valve 3 of the dilute solution pipe 19 of the first absorber 12.
5 is provided, and an on-off valve 36 is installed at the inlet of the intermediate concentrated solution pipe 18. Further, an on-off valve 37 is also attached to the refrigerant liquid pipe 23 to the second evaporator 11 . Next, the operation will be explained. When operating the two-stage system, on-off valves 30, 3g are closed, and on-off valves 31°, 32.35,
36 and 37 are open. The flow of solution and refrigerant at this time is the same as in the conventional example. Next, when the single-stage system is in operation, the on-off valves 30, 33 are open, and the on-off valves 31, 21. ．． 35, 36, and 37 are closed. At this time, a heat source such as exhaust heat that serves as a driving source enters the generator 5 and the heating heat exchanger 7.10 of the first evaporator 9, and high-temperature steam supplied to the process is obtained from the second absorber 14. It will be done. In addition, the cooling water is supplied to the cooling heat exchanger 8 of the condenser 6.
Flow. The shell C3 housing the second evaporator 11 and the first absorber 12 has a circuit in which neither the solution nor the refrigerant flows. The dilute solution returned to the generator 5 from the second absorber 14 of the shell D4 through the bypass pipe 34, the on-off valve 33 and the dilute solution pipe 19 is heated by the heating heat exchanger 7, and the refrigerant is converted into steam and 17 Release with. The released refrigerant vapor goes to the condenser 6 and is transferred to the cooling heat exchanger 8.
After being cooled and condensed into liquid, the refrigerant passes through the refrigerant liquid pipe 22 by the refrigerant pump 24 to the first evaporator 9. After the refrigerant liquid is heated and evaporated by the heating heat exchanger 10 in the first evaporator 9, this refrigerant vapor is transferred to the refrigerant vapor pipes 25 and 2.
8. Passes through the on-off valve 30 to the second absorber 14. On the other hand, outbreak @! ! The concentrated solution, which has become more concentrated by discharging the refrigerant in step 5, passes through the concentrated solution pipe 17 by the solution pump 16.
The first heat recovery heat exchanger 20 exchanges heat with the high-temperature solution from the second absorber 14 , and the temperature rises and goes to the second absorber 14 . The concentrated solution that has entered the second absorber 14 passes through the refrigerant vapor pipes 25 and 28 and flows into the second absorber 14 from the first evaporator 9 while flowing down the outer wall surface of the heat transfer tube 15. absorbs and generates heat at high temperatures. Due to this heat generation effect, the process water flowing through the heat transfer tube 15 is heated and becomes high-temperature hot water or steam, which is supplied to the process from the process water tube 27. The dilute solution, which has absorbed refrigerant vapor and has become diluted in concentration, returns to the generator 5 through the bypass pipe 34, the on-off valve 33, the dilute solution pipe 19, and the first heat recovery heat exchanger 20. Note that when the dilute solution passes through the first heat recovery heat exchanger 20ie,
The temperature is lowered by heat exchange with the concentrated solution. In the above embodiment, the flow of each container and liquid is shown in Fig. 11199 with pumps, heat recovery heat exchangers, etc. omitted. Although we have described switching between a single-stage system and a two-stage system for a system in which the absorption gas enters the first and second evaporators in parallel, the system is not limited to this system, and as shown in Figure 3, absorption The liquid enters the J-th absorption tank and the second absorber in parallel from the generator, and the refrigerant liquid goes from the condenser to the fourth evaporator to the second evaporator.
The on-off valve 33 in the circuit returning from the absorber to the generator is omitted. In addition, there is a system in Figure 4 where the absorption liquid flows from the generator to the first absorber to the second absorber, and the refrigerant liquid flows from the condenser to the second evaporator to the first evaporator, and the flow of the absorption liquid and refrigerant. A combination between FIGS. 2 to 4 may be used. Note that in the system shown in FIG. 4, an on-off valve 38 is added. Further, in FIGS. 2 to 4, the solid line shows the absorption liquid circuit, the broken line shows the refrigerant vapor circuit, and the one-dot chain line shows the refrigerant liquid circuit.

【Effect of the invention】

As explained above, this invention includes an on-off valve that opens and closes the solution entrance and exit port to the first absorber, a bypass circuit that bypasses this, an on-off valve for bypass circuit-F, and an on-off valve that opens and closes the refrigerant liquid circuit to the second evaporator. By providing on-off valves, circuits that connect the first evaporator and second absorber, and on-off valves, it is possible to switch between a single-stage system and a two-stage system, making it possible to use heat efficiently. effective.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of an absorption heat pump of the present invention, FIG. 2 is a block diagram of the absorption heat pump with the pump and heat recovery heat exchanger omitted, and FIGS. The figures are block diagrams of other embodiments of the absorption heat pump of the present invention, and FIG. 5 is a diagram showing the configuration of a conventional absorption heat pump. 1 to 4- Shell A to Shell D, 5 Generator, 6 Condenser, 9 First evaporator, 11 Second evaporator, 12 First absorber, 14 Second absorber, 17 Concentrated solution tube, 18... Intermediate concentrated solution pipe, 19 Dilute solution pipe, 22.23 - Refrigerant liquid pipe, 25, 26, 28, 29 Refrigerant vapor pipe, 30-33.3
5-38・On-off valve, 34・Bypass pipe. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Masuo Oiwa (and 2 others) Figure 2
Do3x ′♀ 5 Figure

Claims (3)

[Claims] (1) A first shell with a generator and a condenser, a second shell with a first evaporator, a third shell with a second evaporator and a first absorber, a fourth shell with a second absorber The generator is connected to the first absorber and the second absorber by a reciprocating tube for solution, and the generator is connected to the first absorber and the second absorber in parallel or from the generator to the second absorber and the second absorber. The second absorber is connected in series with the first absorber, or the generator is connected in series with the first absorber and the second absorber, and the condenser and the first and second evaporators, or the second The first evaporator, the first absorber, and the second absorber are connected to the evaporator by a refrigerant liquid pipe.
In an absorption heat pump configured by connecting an evaporator and a second absorber with a refrigerant vapor pipe, on-off valves 35 are provided at the solution pipe outlet and inlet of the first absorber to open and close the valves, respectively.
, 37, an on-off valve 37 for turning on and off the refrigerant liquid supply to the refrigerant liquid pipe line to the second evaporator, the first evaporator and the first absorber, and the second evaporator and the second absorber. An absorption heat pump characterized in that the connected refrigerant vapor pipes are provided with on-off valves 31 and 32, respectively, and a bypass pipe is provided with an on-off valve 30 that bypasses the first absorber. (2) In a configuration in which the solution circuit is connected in series from the generator to the second absorber and the first absorber, or the first absorber and the second absorber, the solution circuit bypasses the first absorber. 2. The absorption heat pump according to claim 1, further comprising an on-off valve 33 in this circuit. (3) In a heat pump configured with a circuit in which the refrigerant liquid flows from the condenser to the second evaporator and then to the first evaporator, there is a circuit that bypasses the second evaporator and goes to the first evaporator, and an on-off valve 38 in this circuit. Claim 1 characterized in that
Absorption heat pump as described in section.