JP3176536B2 - Absorption refrigerator and its operation control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption chiller and an operation control method at the time of starting the absorption chiller, and in particular, to facilitate the operation of the absorption chiller at the time of startup and greatly reduce the possibility of damage to equipment. In addition, the present invention relates to an absorption chiller adapted to appropriately cope with a load fluctuation during normal operation and an operation control method at the time of starting the absorption chiller.

[0002]

2. Description of the Related Art Absorption refrigerators using water as a refrigerant and a highly hygroscopic substance such as an aqueous solution of lithium bromide as an absorption solution are known. FIG. 6 is a system flow chart for explaining the operation principle of the single-effect absorption refrigerator. The refrigerant vapor generated in the evaporator E is absorbed in the absorption solution (for example, lithium bromide aqueous solution) in the absorber A, and the refrigerant is absorbed. Is diluted by the solution pump SP into a regenerator G.
Sent to The regenerator G has a burner B, and the diluted absorption solution evaporates the refrigerant by heating from the burner B, is concentrated, and flows out to the absorber A again. The vaporized refrigerant is condensed in the condenser C and sent to the evaporator E. In the drawing, RP is a refrigerant circulation pump that circulates the refrigerant in the evaporator E. HX is a heat exchanger for the absorbing solution, and exchanges heat between the low-temperature absorbing solution sent from the solution pump SP to the regenerator G and the high-temperature absorbing solution flowing from the regenerator G to the absorber A. By doing so, the thermal efficiency of the absorption refrigerator is improved. Further, in the figure, S1 is a temperature sensor that measures the temperature of the absorbing solution in the regenerator G, and S2 is a level sensor that measures the liquid level of the absorbing solution in the regenerator G. Further, S3 and S4 are also temperature sensors and measure the temperature of the cold water from the evaporator.

In this absorption refrigerator, the absorption solution is supplied from the absorber A to the regenerator G by the solution pump SP as described above.
The outflow from the regenerator G to the absorber A is caused by the pressure difference between the internal pressure P _RVH of the regenerator G and the internal pressure P _{RVL of the} absorber A. For this purpose, in the conventional absorption refrigerator, the control at the time of starting is performed according to the sequence shown in FIG. 8A. As a procedure, the burner B is ignited (however, the solution pump SP is stopped).

[0004] The temperature of the absorbing solution in the regenerator G rises and exceeds a specified value (measured by the temperature sensor S1). Thereby, the internal pressure _PRVH in the regenerator G increases, and the absorbing solution flows due to the differential pressure. Due to the flow of the absorbing solution, the liquid level in the regenerator G becomes equal to or lower than the specified value (LH) (measured by the level sensor S2).

[0005] The solution pump SP is started. Hereinafter, normal operation is performed. The solution pump SP is not started until a certain pressure difference is generated between the regenerator G and the absorber A. 8B, sensors S4 and S3 for measuring the outlet temperature of the cold water from the evaporator E are provided for the partial load in the normal operation state,
The measures are taken by proportionally controlling the gas combustion amount of the burner B of the regenerator G with respect to the outlet temperature of the chilled water and controlling the flow rate of the solution pump SP in proportion to the outlet temperature of the chilled water. Further, when the liquid level of the absorbing solution in the regenerator G exceeds the upper specified value (LH) for some reason, the solution pump SP is stopped to make it lower than the specified value, and conversely, the liquid level becomes lower specified value (LL). When the level becomes lower than the lower limit, the fuel flow of the burner B of the regenerator G is controlled by restricting.

FIG. 7 is a system flow chart for explaining the operation principle of the double effect absorption refrigerator. In this case, a high temperature regenerator HG and a low temperature regenerator LG are used as regenerators, and a high temperature regenerator is used. The absorption solution flowing out of the HG flows into the low-temperature regenerator LG, where it exchanges heat with the refrigerant vapor from the high-temperature regenerator HG, and then flows into the absorber A. In this case, the diluted absorption solution from the solution pump SP is combined with the heat-concentrated absorption solution flowing out of the high-temperature regenerator HG and the high-temperature heat exchanger HX, and the heat-concentration absorption solution flowing out of the low-temperature regenerator LG. In the low-temperature heat exchanger LX,
By performing the heat exchange twice, and also in the low-temperature regenerator LG, the absorption solution is heated, so that high thermal efficiency can be achieved.

In this double-effect absorption refrigerator, the absorption solution is pumped from the absorber A to the high-temperature regenerator HG by the solution pump SP as described above.
From the high-temperature regenerator LG to the low-temperature regenerator LG
_By the differential pressure between _RVH and the internal pressure P _RVM of the low temperature regenerator LG,
In addition, the outflow from the low-temperature regenerator LG to the absorber A is caused by a differential pressure between the internal pressure P _RVM of the low-temperature regenerator G and the internal pressure P _{RVL of the} absorber A. The time control is performed according to the sequence shown in FIG. 8, as in the case of the single-effect absorption refrigerator.

[0008]

The present inventors have been conducting continuous research and experiments on a regenerator used in the absorption refrigerator described above. The regenerator, in which the heat transfer tubes are arranged closer to the flame of the burner than those of the above, can make the combustion chamber compact and absorb the solution to the heat transfer tubes arranged closer to the burner. By devising the mode of feeding, corrosion and crystallization of the heat transfer tube caused by high heat flux (solvent such as water is excessively evaporated, and the amount of solute (absorbing solution) exceeds the solubility in the solvent. Low NO _x without causing the solute to precipitate as crystals).
He perceived that it was possible to obtain a regenerator capable of operating stably for a long period of time while achieving combustion and low unburned combustion, and filed an application as an improved regenerator.

FIGS. 1 and 2 show an example of such an improved regenerator for an absorption refrigerator. The regenerator A includes a side wall 11 of the main casing 1 and a heat transfer chamber 2 penetrating the main casing 1. An intermediate partition 31 is provided between the heat transfer chamber 2 and the upper wall 22 of the heat transfer chamber 2, that is, the upper end of the intermediate partition 31 reaches the inside of the upper absorbent solution reservoir 6. . In addition, the lower ends of the left and right intermediate partition walls 31 reach between the bottom plate 23 of the heat transfer chamber 2 and the bottom plate 12 of the main casing 1, that is, the lower absorbent solution reservoir 5,
It is connected by an intermediate bottom plate 33 having many holes 34. Accordingly, the lower absorbing solution reservoir 5 is divided into the first lower absorbing solution reservoir 5a and the second lower absorbing solution reservoir 5b by the intermediate bottom plate 33, and both are communicated by the hole 34 of the intermediate bottom plate 33.

A large number of heat transfer tubes 7 (first heat transfer tube group) are attached to the downstream side of the heat transfer chamber 2 in the same manner as in the conventional regenerator, and a lower absorbent solution reservoir 5 (first lower absorbent solution reservoir 5a) is provided. ) And the upper upper absorbent solution reservoir 6 are formed. An upstream side of the first heat transfer tube group 7;
That is, on the side close to the burner 3, a plurality of second heat transfer tube groups 71 constituting a second absorption solution ascending flow path are arranged in a substantially vertical direction similarly to the first heat transfer tube group 7, The lower end of the second heat transfer tube group 71 reaches the intermediate bottom plate 33.

On the back surface of the intermediate bottom plate 33 where the lower end opening of the second heat transfer tube group 71 is located, the lower end opening side of the second heat transfer tube group 71 is located at the lower absorbent solution pool 5 (first
Lower absorption solution reservoir 5a and second lower absorption solution reservoir 5
A rectangular frame 35 for isolating from the space b) is fixed, and a pipe 8 is connected to the bottom of the rectangular frame 35. The rectangular frame 35 functions as the absorbing solution inlet header in the present invention.

Further, the shielding plate 3 is located above the upper absorption solution reservoir 6 and above the second heat transfer tube group 71.
6 is fixed, and blocks upward scattering of the absorbing solution ejected from the upper opening of the second heat transfer tube group 71 as described later. The regenerator A for the absorption refrigerator is used in the same manner as the regenerator G shown in FIG. 6 or the high-temperature regenerator HG shown in FIG. That is, the absorbing solution from the absorber A, which is diluted by absorbing the refrigerant vapor, is sent from the pipe 8 into the rectangular frame 35 which functions as an absorbing solution inlet header by the solution pump SP, and comes close to the burner 3. The liquid is forcibly fed to the upper absorbing solution reservoir 6 through the second heat transfer tube group 71 constituting the second absorbing solution ascending flow path arranged at the position. While passing through the second heat transfer tube group 71, the absorbing solution is exposed to a strong heat flux, but the entire amount of the absorbing solution pumped by the solution pump SP passes through the second heat transfer tube group 71. The flow velocity is high and effectively absorbs high heat flux without causing corrosion or crystallization in the heat transfer tube.

The absorbing solution ejected from the second heat transfer tube group 71 spreads over the entire surface of the upper absorbing solution reservoir 6 while being prevented from being scattered by the upper shielding plate 36, and is formed between the side wall 11 of the main casing 1 and the intermediate partition 31. It flows down the flow path (return flow path) between the first lower absorbent solution 5b and the second lower absorbent solution reservoir 5b, and then enters the first lower absorbent solution reservoir 5a through a number of holes 34 formed in the intermediate bottom plate 33. Then, from there, it passes through the first heat transfer tube group 7 constituting the first absorption solution ascending flow path and the flow path formed by the wall 21 and the intermediate partition 31 of the heat transfer chamber 2, and again, the upper absorption solution Return to pool 6.

During the forced convection of the absorbing solution to the second heat transfer tube 71 and the subsequent circulation by natural convection, the refrigerant (water) absorbed by the absorbing solution is vaporized by the heat from the burner 3,
The absorption solution concentrated by vaporization of the refrigerant is supplied from the pipe 9 to the absorber A (in the case of a double effect absorption refrigerator, the low-temperature regenerator L is used).
G to the absorber A) and again absorbs the refrigerant. On the other hand, the refrigerant vapor is sent to the condenser C.

According to the regenerator for an absorption refrigerator according to the above proposal, even if the heat transfer tubes 7 and 71 are arranged in almost the entire area inside the heat transfer chamber 2, the heat transfer tubes close to the burner as in the conventional regenerator. No corrosion or crystallization occurs in the heat tube 71. Therefore,
The entire regenerator having the same capability can be designed to be more compact than before, and there is no tendency to shorten the life. Furthermore, the decrease in residence time at high temperature field decreases and the combustion gases of the flame temperature, it is possible to lower NO _x combustion,
Further, the generation of unburned components is also suppressed.

The inventors of the present invention have continued experiments on an absorption refrigerator equipped with a regenerator with forced circulation of an absorption solution according to the above-mentioned proposal, so that at the time of startup, the control as shown in FIG. When doing, I knew that there would be some inconvenience. That is, when the burner B is burned in a state where the solution pump SP is stopped at the time of start-up, the absorption solution does not substantially flow in the second heat transfer tube 71 disposed close to the burner. The heat flux cannot be absorbed, and corrosion and crystallization in the heat transfer tube 71 may occur.

As a solution to this problem, when the solution pump SP is operated from the beginning of operation and operated, the regenerator G and the absorber A
(In the case of a single-effect absorption refrigerator) or the pressure difference between the high-temperature regenerator HG to the low-temperature regenerator LG and the low-temperature regenerator LG to the absorber A (double-effect absorption refrigerator) ), The absorption solution did not flow and the absorber A
There is a possibility that the amount of the absorbing solution in the absorber A becomes insufficient due to the insufficient flow of the absorbing solution into the solution A, and cavitation may occur on the suction side of the solution pump SP.

In the case of performing the above-mentioned control at the time of a partial load or at the time of an abnormal liquid level during the normal operation, the liquid level in the regenerator is controlled only by controlling the gas combustion amount and the absorption solution flow rate. Is difficult to stabilize,
There may be a case where the solution pump SP must be stopped and controlled. As a result, as described above, since the absorbing solution is not substantially fed through the second heat transfer tube 71 disposed close to the burner, it is not possible to absorb a high heat flux, and the same as at the time of startup. In addition, corrosion and crystallization in the heat transfer tube 71 may occur.

Accordingly, a main object of the present invention is to solve the above-mentioned inconveniences which may occur when the improved regenerator, which has already been proposed by the present applicant, is installed in an absorption refrigerator and started. That is, an absorption refrigerator and a method for controlling the operation of the absorption refrigerator that have solved the possibility of the occurrence of corrosion and crystallization in the heat transfer tube at the time of startup and normal operation, and the possibility of the occurrence of cavitation in a solution pump. It is to disclose.

[0020]

One embodiment of an absorption refrigerator according to the present invention for solving the above-mentioned problems is a regenerator, for example, as described with reference to FIGS. A heat transfer tube group having a heating burner and a large number of heat exchange tube groups for heat exchange, wherein all or a part of the diluted absorption solution fed from the solution pump is close to a burner of the heat transfer tube group. In the absorption refrigerator using a regenerator of the type that is forcibly fed into the regenerator only through the recirculator, the absorption solution heated and concentrated by the regenerator is discharged to the absorber. Has a pipe portion passing through a heat exchanger for exchanging heat between the absorbing solution passing therethrough and the absorbing solution discharged from the solution pump, and further, the heat exchanger Flow resistance is lower than that of the pipe section passing through Bypass channel are provided as parallel branch paths the conduit portion, the said bypass passage, characterized in that the valve is located.

According to another aspect of the present invention, there is provided a method for controlling the operation of an absorption refrigerator according to the present invention, which comprises: an evaporator, an absorber, a regenerator, and a refrigerant vapor generated in the evaporator. An absorption refrigeration system having a solution pump for feeding the diluted absorption solution from the absorber to the regenerator, and an outlet pipe for allowing the absorption solution heated and concentrated in the regenerator to flow to the absorber. Operating flow control method, wherein the outflow pipe partially has two branch flow passage portions which are parallel to each other but have different flow passage resistances, and the two branch flow passage portions are provided in accordance with an operation environment. It is characterized by operating by adjusting the flow rate of the absorbing solution through the section.

The absorption refrigerator described in the present invention may be a single-effect absorption refrigerator or a double-effect absorption refrigerator. In the latter case, the present invention is applied to the high-temperature regenerator. In the absorption refrigerator according to the present invention, the solution pump is driven from the start, and is not stopped during operation. Then, at the time of startup, the absorbing solution heated by the regenerator flows out to the absorber through a flow path having a low flow resistance in the two parallel branch flow paths in the outflow pipe to the absorber. . That is, at startup, the burner is ignited and the solution pump is driven,
Further, the operation is performed in a state where a valve provided in a bypass flow path which is a branch path arranged in parallel with a pipe portion (having a high flow resistance) passing through the heat exchanger of the outflow pipe is opened.

The temperature of the absorbing solution in the regenerator rises due to the heating of the burner, and the pressure rises due to the vaporization of the refrigerant. In the conventional absorption refrigerator, the outflow pipe between the regenerator and the absorber (in the case of the double effect absorption refrigerator, the outflow pipe between the high temperature regenerator and the low temperature regenerator) is inside the heat exchanger. Since the heat exchanger usually has a high flow path resistance, the differential pressure caused by the pressure increase in the regenerator at the initial stage of startup is sufficient for the absorption solution to flow down to the absorber. Instead, it caused cavitation in the solution pump.However, the outflow pipe according to the present invention has a bypass flow path having a small flow path resistance, and is also affected by a low pressure rise in the regenerator at the initial stage of startup. The absorption solution can easily flow out to the absorber through the bypass channel. This allows the solution pump to continue stable operation without cavitation.

This means that as a result, a sufficient amount of the absorbing solution can be supplied to the heat transfer tubes of the regenerator, and the high heat flux is effectively absorbed, and the heat transfer tubes are corroded or damaged. Crystallisation is avoided. When the temperature of the absorbing solution in the regenerator becomes equal to or higher than the set value, that is, between the regenerator and the absorber (in the case of a double effect absorption refrigerator, between the high temperature regenerator and the low temperature regenerator, At or before or after a predetermined differential pressure is generated between the low-temperature regenerator and the absorber), the valve of the bypass flow passage is closed, and thereafter, the absorption refrigerator is operated in the same manner as in the conventional case. Normal operation is performed.

In the course of normal operation, if the level of the absorbing solution in the regenerator becomes abnormally high for some reason, the valve of the bypass passage is opened. Thereby,
The flow resistance of the outflow pipe becomes small, and the absorbent solution in the regenerator can easily flow down to the absorber (low-temperature regenerator in the case of a double effect absorption refrigerator), and the absorption in the regenerator The level of the solution drops. When the predetermined level is reached, the valve of the bypass flow path is closed and the operation is continued.

According to the absorption refrigerator of the present invention and the operation control method thereof, it is possible to continue the operation without stopping the solution pump even when an abnormality occurs during the normal operation as described above. This means that a sufficient amount of absorbing solution is always supplied to the heat transfer tubes of the regenerator,
Corrosion and crystallization of the heat transfer tubes are reliably avoided, and the life of the equipment is prolonged.

The present invention also relates to a conventionally known absorption refrigerator as shown in FIG. 6 or 7, that is, an absorption refrigerator having a regenerator of a conventionally known type and a method of controlling the operation thereof. Applicable. Even in such a case, it will be understood that the risk of heat damage to the regenerator and the danger of cavitation of the solution pump at the time of start-up or abnormality can be avoided, and the life of the equipment is prolonged.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an absorption refrigerator according to the present invention and an operation control method thereof will be described in more detail based on preferred embodiments shown in the drawings. FIG. 3 is a system flow diagram showing an embodiment of an absorption refrigerator according to the present invention. Basically, a conventionally known single-effect absorption refrigerator described above based on the system flow diagram shown in FIG. The same as the refrigerator, but the regenerator Ga used has a heating burner B and a large number of heat exchange heat transfer tube groups 7, 71 as shown in FIGS. And all or part of the diluted absorbing solution sent from the solution pump SP is forcibly sent into the regenerator Ga only through the heat transfer tube group 71 close to the burner of the heat transfer tube group. The difference is that it is of the type that is intended to be used. Therefore, other configurations of the single-effect absorption refrigerator are only given the same reference numerals in the drawings, and description thereof is omitted.

In this single-effect absorption refrigerator, the outflow pipe Pa from the regenerator Ga to the absorber A has a bypass flow path P in parallel with a portion passing through the solution heat exchanger HX.
b is formed as a branch, in which a valve V is mounted. The bypass flow path Pb is preferably a pipe having the same inner diameter as the outflow pipe Pa, but may have a somewhat larger diameter. The valve V is opened and closed by temperature information from a temperature sensor S1 for measuring the temperature of the absorbing solution in the regenerator Ga, and by position information from a level sensor S2 for measuring the height of the solution in the regenerator Ga. You.

FIG. 5A is a sequence diagram showing a control state at the time of startup in the absorption refrigerator described above. As a procedure, the solution pump SP for igniting the burner B is started. Open valve V.

The temperature of the absorbing solution in the regenerator Ga becomes equal to or higher than a specified value (the internal pressure P _RVH in the regenerator Ga increases, and is sufficient for the absorbing solution to pass through the heat exchanger HX and flow out to the absorber). High differential pressure). Close valve V. Hereinafter, normal operation is performed.

The operation is performed as follows. According to this embodiment, the solution pump SP is activated simultaneously with the ignition of the burner B, but the valve V is open, and the regenerator Ga and the absorber A are connected via the bypass flow path Pb having a low flow resistance. It is connected, and a sufficient amount of the absorbing solution flows out to the absorber A from the beginning of startup. As a result, no cavitation occurs in the solution pump SP, and a sufficient amount of the absorbing solution is forcibly fed to the heat transfer tube group 71 close to the burner B of the regenerator Ga. Corrosion and crystallization in the group 71 are also avoided. When the temperature of the absorbing solution in the regenerator Ga reaches a predetermined temperature (a temperature at which a required differential pressure can be obtained), the valve V is closed and normal operation is performed. It can flow out through the HX to the absorber, and cavitation does not occur in the solution pump SP.

During normal operation, the regenerator G for some reason
When the liquid level of the absorbing solution in a becomes abnormally high, the valve V of the bypass flow path Pb is opened by a signal from the level sensor S2. As a result, the flow path resistance of the outflow pipe Pa decreases, and the absorbing solution in the regenerator Ga flows down to the absorber A at a larger unit time flow rate. As a result, the solution level immediately becomes an appropriate value, and as a result, the solution pump S
An appropriate flow rate from P is secured. Therefore, the cavitation of the solution pump SP occurs or the heat transfer tube group 71
The occurrence of corrosion and crystallization in the interior is avoided. The valve V is closed at the time of the proper state.

As the valve V provided in the bypass passage Pb, a flow control valve can be used. In that case,
The set temperature of the absorbing solution in the regenerator Ga is set to 1 to n,
The closing amount (throttle amount) of the flow control valve is set to 1 according to the set temperature.
To n, the valves are closed in multiple stages. In this case, since the flow rate of the absorbing solution passing through the bypass flow path Pb and the heat exchanger HX can be changed stepwise,
There is an advantage that the switching between the start-up operation and the steady operation is smooth.

FIG. 4 is a system flow diagram when the single-effect absorption refrigerator described with reference to FIG. 3 and the operation control method thereof are applied to a double-effect absorption refrigerator. 7 is the same as the conventionally known double effect absorption refrigerator described above with reference to the system flow diagram shown in FIG. 7, but also in this case, the high temperature regenerator HGa used is Heat transfer tube groups 7 and 71 for heat exchange, and all or a part of the diluted absorbing solution supplied from the solution pump SP is located near the burner of the heat transfer tube group. A type that is forcibly fed into the high-temperature regenerator HGa through only the group 71 is used. Other configurations are the same as those shown in FIG.

In this double effect absorption refrigerator, the outflow pipe P from the high temperature regenerator HGa to the low temperature regenerator LG is also used.
A bypass flow path Pb is formed as a branch path in parallel with a portion passing through the solution heat exchanger HX, and a valve V is attached thereto. The operation control method at the time of start-up and the operation control method at the time of abnormality during normal operation in the above-mentioned double-effect absorption refrigerator are the same as those of the single-effect absorption refrigerator shown in FIG. It will be easily understood. It will also be appreciated that, in this case as well, a flow control valve may be used in place of valve V.

[0037]

According to the present invention, at the time of startup of an absorption refrigerator and at the time of occurrence of an abnormality in a normal operation state, the regenerator may be damaged by receiving a high heat flux or may be damaged by the solution pump. Cavitation can be avoided, and safety can be improved. In particular, the regenerator has a heating burner and a number of heat exchange tubes for heat exchange, and all or a part of the diluted absorption solution sent from the solution pump is supplied to a burner of the heat transfer tubes. The present invention works effectively in the case where it is forcibly fed into the regenerator only through the adjacent heat transfer tube group.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of a regenerator for an absorption refrigerator in which the present invention functions particularly effectively.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a system flow diagram illustrating an embodiment in which the present invention is applied to a single-effect absorption refrigerator.

FIG. 4 is a system flow diagram illustrating an embodiment in which the present invention is applied to a double-effect absorption refrigerator.

FIG. 5 is a sequence chart showing a control state of the operation control method of the absorption refrigerator according to the present invention.

FIG. 6 is a system flow diagram illustrating a conventional single-effect absorption refrigerator.

FIG. 7 is a system flow diagram illustrating a conventional double-effect absorption refrigerator.

FIG. 8 is a sequence chart showing a control state of a conventional operation control method of an absorption refrigerator.

[Description of sign]

A: absorber, C: condenser, E: evaporator, Ga: regenerator,
SP: solution pump, B: burner, S1, S3, S4 ...
Temperature sensor, S2: level sensor, Pa: outflow pipe of absorption solution, Pb: bypass flow path, V: valve

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Masatoshi Asakawa 1-5-5 Minami-Otsuka, Toshima-ku, Tokyo (56) References JP-A-1-208672 (JP, A) JP-A-6-347121 (JP, A) JP-A-9-42799 (JP, A) JP-A-9-33136 (JP, A) JP-B-58-10663 (JP, B2) JP-B-63-42181 (JP, B2) -19406 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25B 15/00 306 F25B 33/00

Claims (2)

(57) [Claims] 1. An evaporator, an absorber, a regenerator, and a solution pump for absorbing a refrigerant vapor generated in the evaporator and feeding a diluted absorbing solution from the absorber to the regenerator.
An outlet pipe for allowing the absorbent solution heated and concentrated by the regenerator to flow out to the absorber; and the regenerator further includes a heating burner and a plurality of heat exchange tube groups for heat exchange. And all or a part of the diluted absorbing solution sent from the solution pump is forcibly fed into the regenerator through only the heat transfer tube group of the heat transfer tube group which is close to the burner. In such an absorption refrigerator, the outflow pipe has a pipe portion passing through a heat exchanger for exchanging heat between the absorption solution passing therethrough and the absorption solution discharged from the solution pump. Further, a bypass flow path having a lower flow resistance than a pipe part passing through the heat exchanger is provided as a branch path parallel to the pipe part, and a valve is arranged in the bypass flow path. An absorption refrigerator characterized by being made. 2. An evaporator, an absorber, a regenerator, and a solution pump for absorbing the refrigerant vapor generated in the evaporator and feeding a diluted absorption solution from the absorber to the regenerator.
The absorbent solution is heated and concentrated in said regenerator has a outflow pipe for causing outflow to the absorber, further, before
The regenerator has a heating burner and a number of heat exchange tubes for heat exchange.
And the diluted suction supplied from the solution pump.
All or a part of the collected solution is a burner of the heat transfer tube group.
Forcibly into the regenerator only through the heat transfer tube group close to
An operation control method for an absorption refrigerator that is adapted to be inserted, wherein the outflow pipes have two branch flow paths that are partly parallel to each other but have different flow path resistances, An operation control method of an absorption refrigerator, wherein the operation is performed by adjusting the flow rate of an absorption solution passing through two branch flow paths according to an operation environment.