JP3280169B2 - Double effect absorption refrigerator and chiller / heater - 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 refrigerator and, more particularly, to a double effect absorption refrigerator and a chiller / heater with efficient circulation of a solution.

[0002]

2. Description of the Related Art Conventionally, in order to increase the efficiency (COP: coefficient of performance) of a refrigerator, it has been necessary to increase the heat recovery rate in a heat exchanger. In this case, however, the pressure loss in the heat exchanger is large. It tends to be. For example, in the case of the conventional apparatus shown in FIG. 8, if the pressure loss of the low-temperature heat exchanger becomes large, the solution cannot return to the absorber, so a J-line is provided as shown by a broken line to return directly from the low-temperature regenerator to the absorber. Of course, it is often returned to the absorber from here, but the efficiency drops significantly. Therefore,
As shown in FIG. 9, a solution spray pump is provided to back up the pressure. In this case, all of the circulating solution is circulated by the solution spray pump, and the individual circulation amount cannot be adjusted. It was also an economic problem.

[0003]

SUMMARY OF THE INVENTION The present invention solves the above problems and provides an efficient and economical double-effect absorption refrigerator and chiller / heater in which the circulation of the solution can be separated and adjusted individually. As an issue.

[0004]

According to the present invention, there is provided an absorber, an evaporator, a high-temperature regenerator, a low-temperature regenerator, a condenser, a high-temperature heat exchanger, and a low-temperature heat exchanger. In a double-effect absorption refrigerator in which they are connected by a solution circuit and a refrigerant circuit, the solution circuit supplies a dilute solution from the absorber to the high-temperature regenerator via the high-temperature heat exchanger and the dilute solution from the absorber. a rare solution circuit for supplying to the low temperature generator dilute solution through the low temperature heat exchanger, the strong solution leaving the low temperature regenerator through a solution spray pump through the low <br/> heat exchanger absorber spraying the solution spray pump discharge side concentrated solution circuit leading to equipment, and the concentrated solution leaving the high-temperature regenerator through a hot heat exchanger
And a concentrated solution circuit that leads directly to the absorber spraying device.

[0005] In the present invention, the solution spray pump may be provided with a rotation speed adjusting device for controlling the rotation speed based on a signal for detecting the evaporator refrigerant level or the absorber dilute solution concentration. Further, in the present invention, the double effect absorption refrigerator further includes a bypass circuit having a cooling / heating switching valve for guiding refrigerant vapor from the high-temperature regenerator directly to the evaporator, and directs the refrigerant liquid of the evaporator to the dilute solution circulation system. By providing a bypass circuit having a cooling / heating switching valve for guiding, a double effect absorption cooling / heating machine can be obtained. In the absorption chiller / heater, it is preferable to provide a mechanism for stopping the solution spray pump during the heating operation.

[0006]

In the present invention, the solution circuit is divided into a circuit for circulating a high-temperature regenerator and a circuit for circulating a low-temperature regenerator.
Directly lead to the spraying device of the absorber and back up the solution of the low-temperature regenerator with low pressure by the solution spray pump.
The cycle can be reduced to half of the conventional cycle, and the capacity of the solution spray pump can be reduced.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described specifically with reference to the drawings, but the present invention is not limited thereto. Embodiment 1 FIG. 1 is a flow configuration diagram of a double effect absorption refrigerator of the present invention. In FIG. 1, A is an absorber, GL is a low-temperature regenerator,
GH is a high-temperature regenerator, C is a condenser, E is an evaporator, XL is a low-temperature heat exchanger, XH is a high-temperature heat exchanger, P ₀ is a solution pump,
P ₃ is a refrigerant pump, P ₄ is a solution spray pump,
1 to 9 are solution circuits, and 10 to 13 are refrigerant circuits.

[0008] In cooling operation of the apparatus, a portion of the dilute solution that has absorbed the refrigerant, the absorber part by the solution pump P ₀ from A hot heat exchanger high temperature regenerator to the heated side from the street circuit 2 XH Introduced to GH. In the high-temperature regenerator GH, the dilute solution is heated by the heating heat source to evaporate the refrigerant to be concentrated, and the concentrated solution passes through the path 3 and passes through the high-temperature heat exchanger XH.
, And is introduced into the absorber A through the circuits 6 to 9. On the other hand, the remaining dilute solution through the solution pump P ₀ passes through the heated side of the low temperature heat exchanger XL from circuit 4, is introduced from the circuit 4 to the low-temperature regenerator GL. After the low temperature generator, which is heated and concentrated by the refrigerant vapor from the high temperature generator passes through the heating side of the low temperature heat exchanger XL from the circuit 5 through the absorber circuit 8, the circuit 9 by a solution spray pump P ₄ from the circuit 7 A
Will be introduced.

The refrigerant gas evaporated in the high-temperature regenerator GH passes through the refrigerant circuit 13 and is used as a heat source of the low-temperature regenerator GL, and then is introduced into the condenser C. In the condenser C, the refrigerant is cooled by the cooling water together with the refrigerant gas from the low-temperature regenerator GL, condensed, and enters the evaporator E from the circuit 12. In the evaporator E, the refrigerant is circulated and evaporated by the refrigerant pump P ₃ and the circuits 10 and 11, and at that time, the heat of evaporation is taken from the cold water on the load side, the cold water is cooled, and the cooling water is provided for cooling. The evaporated refrigerant is absorbed by the concentrated solution in the absorber A, becomes a dilute solution, and becomes a cycle circulated by the solution pump. FIG. 3 is a flow chart of only the solution of FIG. 1, and FIG. 5 is a cycle diagram thereof. Thus, in FIG. 1, since the solution spray pump P ₄ are present independently, it is possible to adjust the flow rate. Normally, an adjustment is made such that an amount corresponding to the flow rate sent to the low-temperature regenerator GL or more is guided to the absorber spraying device 9.

Embodiment 2 FIG. 2 shows another flow diagram of the double effect absorption refrigerator of the present invention. In Figure 2, we divide the solution pump and solution pump P ₂ for the solution circulation circuit to the solution pump P ₁ and the low temperature regenerator solution circulation circuit to the high-temperature regenerator is provided separately. Also, a refrigerant level sensor 14 and a controller 15 for controlling the solution spray pump P ₄ and a high temperature regenerator G
A concentrated solution level sensor 16 and a controller 17 of a high-temperature regenerator for controlling the amount of dilute solution circulation to H are provided.

[0011] In the absorption refrigerating machine, (if the solution concentration of the cycle decreases, the refrigerant is reduced) refrigerant liquid amount of the evaporator E is insufficient time to, or when the shortage is expected, the rotational speed of the solution spray pump P ₄ Drop, and the flow rate to the spraying device 9 is reduced. Part of the concentrated solution from the low-temperature regenerator GL bypasses the heat transfer section of the absorber A, enters the dilute solution side, and increases the dilute solution concentration. The increase in the concentration increases the evaporator refrigerant, thereby preventing the refrigerant pump from cavitation due to the shortage of the refrigerant.

A specific control method will be described with reference to FIG. FIG. 6A shows a signal of the refrigerant level sensor 14,
An example of controlling the rotational speed of the solution spray pump P _4.
FIG. 6B shows an example in which the number of revolutions of the solution spray pump is controlled based on the temperature of the cooling water 18 or the concentration of the dilute solution which is very related thereto. This is an example in which the rotation speed of the solution spray pump is controlled based on the load signal of the cold water 19 and the like. In this manner, the cooling water temperature and the cooling water temperature and the cold water load can also be controlled. FIG. 4 is a flow diagram of only the solution of FIG. 2, and FIG. 5 is a cycle diagram thereof.

Embodiment 3 FIG. 7 is a flow diagram of a double-effect absorption chiller / heater provided with a cooling / heating switching valve in the double-effect absorption refrigerator of the present invention so that it can be used for heating. 7, in the absorption refrigerating machine of Figure 1, a bypass pipe 20 having a cooling and heating changeover valve V ₁ for guiding the refrigerant vapor from the high temperature regenerator directly evaporator, the refrigerant liquid from the evaporator to dilute the solution circulation circuit Guided cooling / heating switching valve V
₂ is provided. In FIG. 7, during the heating operation, the cooling / heating switching valves V ₁ and V ₂ are opened to guide the steam of the high-temperature regenerator to the A / E (absorber / evaporator) can body, and to supply hot water passing through the evaporator tube. Heat. Here, the refrigerant vapor condenses and becomes a drain (refrigerant liquid). The refrigerant liquid is returned to the dilute solution circulation system through the valve 2.

In the absorber A, there is no absorption function and the like, and the high-temperature solution is simply flushed to approach the saturation temperature for the refrigerant pressure in the evaporator E. Therefore, no problem even stop the solution spray pump P _4. Therefore, the solution spray pump can be stopped to save pump power. Further, as shown in FIG. 2, the solution pump P ₂ for the low-temperature regenerator
When the low-head pump is provided, the low-head pump and the solution spray pump are stopped to save pump power.

[0015]

According to the present invention, since the solution spray pump is provided independently in the solution circuit circulating through the low-temperature regenerator, the amount of backup by the solution spray pump can be reduced to about 1/2 of the conventional cycle. The flow rate can be adjusted, and safe and efficient operation has become possible.

[Brief description of the drawings]

FIG. 1 is a flow diagram showing an example of a double effect absorption refrigerator of the present invention.

FIG. 2 is a flow configuration diagram showing another example of the double effect absorption refrigerator of the present invention.

FIG. 3 is a solution flow diagram of FIG.

FIG. 4 is a solution flow diagram of FIG.

FIG. 5 is a cycle diagram of FIGS. 1 and 2;

FIG. 6 is a graph for controlling the rotation speed of the solution spray pump.

FIG. 7 is a flow configuration diagram showing an example of a double-effect absorption chiller / heater of the present invention.

FIG. 8 is a solution flow diagram showing an example of a known double effect absorption refrigerator.

FIG. 9 is a solution flow diagram showing another example of a known double effect absorption refrigerator.

[Explanation of symbols]

A: absorber, E: evaporator, GH: high temperature regenerator, GL: low temperature regenerator, C: condenser, XH: high temperature heat exchanger, XL: low temperature heat exchanger, P ₀ , P ₁ , P ₂ : Solution pump, P ₃ : Refrigerant pump, P ₄ : Solution spray pump, V ₁ , V ₂ : Cooling / heating switching valve, 1 to 9: Solution circuit, 10 to 13: Refrigerant circuit,
14: refrigerant level sensor, 15: controller, 16: concentrated solution level sensor, 17: controller, 18: cooling water, 1
9: cold water, 20, 21: bypass pipe

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F25B 15/00 303 F25B 15/00 306

Claims (4)

(57) [Claims] 1. A double-effect absorption refrigerator comprising an absorber, an evaporator, a high-temperature regenerator, a low-temperature regenerator, a condenser, a high-temperature heat exchanger, and a low-temperature heat exchanger, which are connected by a solution circuit and a refrigerant circuit. Wherein the solution circuit supplies a dilute solution from the absorber through the high-temperature heat exchanger to the high-temperature regenerator and a dilute solution that supplies the dilute solution from the absorber through the low-temperature heat exchanger to the low-temperature regenerator. a solution circuit, concentrated solution circuit leading to the absorber spray equipment via solution spraying pump the concentrated solution leaving the low temperature regenerator through the low temperature heat exchanger, and concentrated leaving the solution to high temperature regenerator high said through heat exchanger solution spray pump discharge side
A double-effect absorption refrigerator comprising: a pipe between the absorber sprayer and a concentrated solution circuit that directly leads to the absorber sprayer. 2. The solution spray pump according to claim 1, wherein the solution spray pump is provided with a rotation speed adjusting device for controlling a rotation speed based on a signal for detecting a refrigerant level of the evaporator or a concentration of the dilute solution in the absorber. Double effect absorption refrigerator. 3. The double effect absorption refrigerator according to claim 1, wherein a bypass circuit having a cooling / heating switching valve for directly introducing refrigerant vapor from the high temperature regenerator to the evaporator; And a bypass circuit having a cooling / heating switching valve for leading to a solution circulation system. 4. The double effect absorption chiller / heater according to claim 3, further comprising a mechanism for stopping the solution spray pump during the heating operation.