JP3318302B2 - Absorbent liquid concentrator and absorption refrigerator using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a once-through boiler-type absorption liquid concentrator for separating an absorption liquid and a vapor, and an absorption refrigerator in which the absorption liquid concentrator is integrally combined. Here, the absorption refrigerator includes an absorption chiller / heater.

[0002]

2. Description of the Related Art A conventional double effect steam absorption refrigerator receives steam (steam) supplied from another installed boiler and uses it as a heat source for heating to concentrate an internal solution.
A cooling operation cycle is established by maintaining the inside of the container at a high vacuum with the concentrated solution and continuously absorbing the refrigerant.

[0003] Japanese Patent No. 2960805 discloses an absorption type having a dilute solution introduction path for introducing a dilute solution into a regenerator and a gas-liquid separator at a regenerator outlet where a regenerated regenerate solution is led out. A regenerator for a chiller / heater, which has a heating / boiling system for heating and boiling the dilute solution in the regenerator in a once-through system, and wherein the solution separated by the gas-liquid separator is diluted from the gas-liquid separator. A regenerator is described which is provided with a communication return path led to a solution introduction path, and provided with a check valve in the communication return path to prevent the solution from flowing from the dilute solution introduction path to the gas-liquid separator.

[0004]

In the conventional steam double-effect absorption refrigerator described above, the boiler and the absorption refrigerator are connected by a pipe so as to form a completely closed cycle, and a cycle that can be integrally operated is assembled. If it is possible, it will be possible to perform an operation that saves much energy compared to the conventional double-effect cycle. That is, a new operation cycle (high efficiency cycle) is established by combining the boiler and the absorption refrigerator.

In the regenerator described in the above-mentioned Japanese Patent No. 2960805, a solution for preventing a solution from flowing to a gas-liquid separator in a passage for introducing a dilute liquid from the gas-liquid separator to the regenerator. A check valve is provided. However,
Attachment of a check valve at this position causes a problem that it becomes difficult for the absorbing liquid to circulate at the time of starting or at a low load. See Figure 12 for details
It will be described later with reference to FIG.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a once-through boiler type separator for separating an absorbent and a vapor, which is a dedicated absorbent concentrate for combining with an absorption refrigerator. Is to provide. Further, an object of the present invention is to provide an integrated combination of the above-mentioned absorption liquid concentrator and absorption refrigerator, which makes it possible to reduce the size of the device and simplify the device, and to perform an operation that saves energy. Can,
Another object of the present invention is to provide an absorption refrigerator equipped with a once-through boiler-type absorption liquid concentrator that can increase the efficiency by heat recovery.

[0007]

To achieve the above object, the absorbent concentrator of the present invention is provided with annular headers at the top and bottom, and a number of risers are provided between these headers. ,
A once-through type concentrator equipped with a combustion device in the upper central part, in which the absorbing liquid is introduced into the lower header and heated and concentrated to take out the gas-liquid mixture from the upper header, and a gas-liquid mixture conduit is connected to the once-through concentrator. A vapor-liquid separator connected to the upper part of the gas-liquid separator, an absorbing liquid discharge pipe connected near the lower part of the gas-liquid separator, and a gas-liquid separator. And an absorption liquid supply pipe connected to the absorption liquid circulation pipe and having an absorption liquid supply pump. 1 and 3).

In the absorbent concentrator, it is preferable that a throttle section is provided in the absorbent circulating conduit upstream of the junction of the absorbent circulating conduit and the absorbent supplying pipe (see FIG. 2). An orifice or valve is used as the throttle (see FIG. 2).

[0009] In the above-mentioned absorbent concentrator, a temperature sensor is provided in the vapor extraction conduit, a liquid sensor is provided substantially in the center of the main body of the gas-liquid separator, and a temperature sensor is provided in the absorption liquid extraction conduit. A fuel cutoff valve is provided in a fuel supply pipe connected to the combustion device, and the two temperature sensors, the liquid sensor, the fuel cutoff valve, and the absorption liquid supply pump are electrically connected to an operation control panel, and the temperature of the absorption liquid, When the steam temperature is detected independently or simultaneously and the temperature deviates from the set temperature, the fuel cutoff valve is closed and the fuel supply is stopped, and when the decrease in the supply amount of the absorbing liquid is detected by the liquid sensor, the fuel cutoff valve is closed and the fuel is supplied. It is preferable that the safety circuit is configured to stop the operation (see FIGS. 1 and 3). Further, it is preferable that an absorption liquid supply pump is interlocked with the absorption liquid supply pump, and a double shutoff circuit is configured to stop the fuel supply even when the pump is stopped.

[0010] An absorption refrigerator using the absorbent concentrator of the present invention comprises a double effect absorption refrigerator and any one of the above-mentioned absorbent concentrators, and extracts steam from the absorbent concentrator. Connected so that it can be supplied to the heating side of the high-temperature regenerator via a conduit, and connected so that the absorbing liquid from the absorbing liquid concentrator can be supplied to the heated side of the high-temperature regenerator via the absorbing liquid extraction conduit, It is characterized in that a dilute absorption liquid from an absorption refrigerator is connected to be able to be supplied to a lower header of an absorption liquid concentrator via an absorption liquid supply pipe (see FIGS. 4 and 5).

An absorption refrigerator using the absorption liquid concentrator of the present invention comprises a single (single) effect absorption refrigerator and any one of the above absorption liquid concentrators. Is connected so that it can be supplied to the heating side of the regenerator via the vapor extraction conduit, and can be connected so that the absorbing liquid from the absorbing liquid concentrator can be supplied to the heated side of the regenerator via the absorbing liquid extracting conduit. Further, it is characterized in that a dilute absorbent from the absorption refrigerator is connected so as to be supplied to a lower header of the absorbent concentrate through an absorbent supply pipe (see FIGS. 6 and 7).

Further, the absorption refrigerating machine using the absorbent concentrator of the present invention is characterized in that the absorption liquid is supplied from the absorber in order from a low-temperature heat exchanger, a low-temperature regenerator, a high-temperature heat exchanger, a high-temperature regenerator, a high-temperature heat exchanger, and A bypass configured to circulate through the low-temperature heat exchanger to the absorber, and to bypass a part of the intermediate concentrated absorbent that exits the low-temperature regenerator and is supplied to the high-temperature regenerator to a concentrated absorbent pipe that returns to the absorber; In a reverse cycle steam absorption refrigerator equipped with a pipe, at least a part of the absorption liquid from the high temperature regenerator is extracted into the absorption liquid pipe returning from the high temperature regenerator to the high temperature heat exchanger, and any of the above absorption liquids is extracted. Solution supply means for supplying to the lower header of the concentrator, and the absorption liquid concentrator for heating and concentrating the absorption liquid from the solution supply means are connected in series,
An additional heat exchanger is provided between the solution supply means and the absorbent concentrator for heat exchange between the concentrated absorbent from the high-temperature regenerator and the absorbent heated and concentrated by the absorbent concentrator. To return the heated and concentrated absorbent to the heating side of the additional heat exchanger,
The absorption liquid concentrator and the additional heat exchanger are connected by an absorption liquid extraction conduit, while the refrigerant vapor evaporated from the absorption liquid heated and concentrated in the absorption liquid concentrator is supplied to the high temperature regenerator as a heating source. The absorption liquid concentrator and the high temperature regenerator are connected by a steam extraction conduit (see FIGS. 8 and 9).

Further, the absorption refrigerator using the absorption liquid concentrator of the present invention is configured to circulate the absorption liquid from the absorber to the absorber through the low-temperature heat exchanger, the regenerator and the low-temperature heat exchanger. In a steam absorption chiller, at least a portion of the absorption liquid from the regenerator is extracted to the absorption liquid pipe returning from the regenerator to the low-temperature heat exchanger, and the extracted liquid is sent to the lower header of any of the above absorption liquid concentrators. A solution supply means for supplying, and the above-mentioned absorption liquid concentrator for heating and concentrating the absorption liquid from the solution supply means are connected in series, and a concentrated absorption liquid from the regenerator is provided between the solution supply means and the absorption liquid concentrator. An additional heat exchanger that exchanges heat with the absorption liquid heated and concentrated by the absorption liquid concentrator, and returns the absorption liquid heated and concentrated by the absorption liquid concentrator to the heating side of the additional heat exchanger. The concentrator and the additional heat exchanger are connected by an absorbent extraction pipe, The absorption liquid concentrator and the regenerator are connected by a vapor extraction conduit so that the refrigerant vapor evaporated from the absorption liquid heated and concentrated in the absorption liquid concentrator is supplied to the regenerator as a heating source. (FIGS. 10 and 11
reference).

The conventional double effect absorption refrigerator operates theoretically and practically at a pressure lower than the atmospheric pressure, and there are no restrictions on the structure or handling. Regarding safety, refer to “JIS B 862
2-1994 Absorption chiller ”and JI
Designed and manufactured according to S. Also, depending on the type of heat source supplied from the outside, the heating part of the absorbing liquid may be subject to the structural standard of the pressure vessel, but the majority have a vacuum vessel structure that can be manufactured without standard. . The new operation cycle in the absorption refrigerator of the present invention can reduce energy consumption by about 30% as compared with the conventional double-effect type. It is known that increasing the heat transfer area is effective in saving energy, but the cost and volume increase, so considering the balance between cost and volume, the internal transfer between the refrigerator and the absorbent concentrator (boiler) is considered. It is important to determine the thermal area ratio. By controlling this ratio, it is possible to change the coefficient of performance.

In the new operation cycle of the absorption refrigerator of the present invention, in the case of the double effect type, an absorber, an evaporator, a condenser, a low temperature regenerator, a high temperature regenerator, and an absorption liquid concentrator (boiler).
It is composed of a total of nine heat exchangers of a solution heat exchanger of low temperature, medium temperature and high temperature. In the new operation cycle, the refrigerant vapor generated by heating the solution during operation in the concentrator section exceeds the atmospheric pressure, and the other heat exchanger, which is sequentially heated by the refrigerant vapor generated in this concentrator, uses a liquid seal. Due to such factors, the interior is designed and planned to be below atmospheric pressure.
The liquid seal includes a U seal and a float valve seal. Therefore, only the concentrator is designed and planned according to the structure standard of the pressure vessel or boiler, and the other parts are designed and planned as vacuum vessels. In addition, as a measure for increasing the energy saving rate without increasing the heat transfer area, a heat recovery unit that exchanges heat between the exhaust gas and the absorbing liquid circulating in the vacuum part may be added as necessary.

In the case of the absorption method, there are two heating methods, heating by steam and heating by directly burning fuel. If the heating method is steam, the concentrator section is subject to the pressure vessel structure standard. In the case of direct combustion of fuel, the boiler structure standard is applied when the following conditions are satisfied. That is, "direct heating with a combustion device",
"Supply steam elsewhere" and "Internal pressure exceeds atmospheric pressure." The heat transfer area and volume of the concentrator (boiler) that directly burns the fuel are as follows. (1) The structure of the concentrator that directly burns fuel is a once-through type (boiler). The heat transfer area, 5 m ² or less simple boiler construction codes, 10 m ² or less corresponds to divided into small boiler construction codes. When a simple boiler is used, the internal volume of the gas-liquid separator is set to 20 liters or less. When a small boiler is used, the internal volume of the gas-liquid separator is set to 70 liters or less. (2) The volume ratio between the absorption refrigerator and the boiler is 10: 1 to 2
The absorption chiller side volume is remarkably large at about 0: 1. Therefore, even if the pressure on the concentrator side rises and the safety valve opens, the volume on the refrigerator side is sufficiently large even if the blown steam flows into the refrigerator side, and the pressure on the concentrator side is lower than the design pressure. Therefore, the outlet of the safety valve is connected to an absorption refrigerator (vacuum vessel) without opening to the atmosphere. This allows
At the same time, it is possible to avoid opening to the atmosphere without impairing the function of the safety valve, and it is possible to maintain the most important vacuum for the absorption refrigerator.

The steam flow in the absorption refrigerator of the present invention is as follows. (1) A mixture of the absorbing liquid and water is supplied to an absorbing liquid concentrator (hereinafter, referred to as a once-through boiler) from an absorbing liquid circulation pump attached to the absorption refrigerator. (2) The mixed liquid is heated in the once-through boiler, and the water evaporates to become steam and rises in the riser together with the absorbing liquid. The vapor and the absorption liquid flowing from the upper header to the gas-liquid separator are separated into the vapor and the absorption liquid in the gas-liquid separator, and the vapor flows to the high-temperature regenerator as a heating source of the absorption refrigerator. (3) In the high-temperature regenerator, the steam exchanges heat with the intermediate-concentration absorbent and is cooled, condensed, and flows to the next low-temperature regenerator. (4) The condensed water supplied to the low-temperature regenerator and the refrigerant vapor generated in the high-temperature regenerator are again used as a heating source for the rare absorbing liquid in the low-temperature regenerator, and the condensed water and the refrigerant vapor have low concentrations. It exchanges heat with the absorbing liquid and is further cooled and condensed and flows to the condenser. (5) The condensed water flowing to the condenser and the refrigerant vapor generated in the low-temperature regenerator are cooled by the cooling water in the condenser, sufficiently cooled, condensed, and flow to the evaporator. Since both the condenser and the low-temperature regenerator are in a vacuum state of, for example, about 1/15 atm, water condenses at about 35 to 40 ° C. (6) In the evaporator, water (refrigerant) evaporates again in a vacuum state by removing heat from the external heat load. In the evaporator, for example, water (refrigerant) evaporates at about 3 to 5 ° C. due to a high vacuum of about 1/150 atm, and cools a heat load coming from the outside to exhibit a cooling effect. (7) The refrigerant evaporated by removing heat from the outside in the evaporator is absorbed by the absorbing liquid sprayed in the absorber and condensed.
The absorbing liquid has a low vapor partial pressure as compared with water and has a property of being easily mixed with water, and therefore has an important meaning for maintaining a high vacuum in the evaporator. (8) The water (refrigerant) mixed with the absorbing liquid in the absorber is supplied again to the once-through boiler for separation into the absorbing liquid and water.

The flow of the absorbing solution is as follows. (1) After separating into vapor and absorbing liquid by the gas-liquid separator, the absorbing liquid exchanges heat with low-temperature (low-concentration) absorbing liquid in a plurality of heat exchangers, then flows to the absorber, and is sprayed by the liquid spraying device. Sprayed by the absorber to absorb water (refrigerant). (2) Since the absorbing liquid absorbs and mixes water, it becomes a low-concentration absorbing liquid and it becomes difficult to continuously absorb water. Therefore, it is necessary to heat the absorbing liquid again to separate the absorbing liquid and water. (3) A heat exchanger such as a regenerator, a heater, a concentrator, and a once-through boiler is provided for heating and concentrating the absorbing solution, and a plurality of them are combined in series or in parallel to further increase the efficiency.

In order to make the above-mentioned steam flow and absorption liquid flow smoothly, a conventional absorption refrigerator is combined with a once-through boiler which supplies a rare absorption liquid and separates it into absorption liquid and vapor. Form a closed circuit. In this way, the combination of a once-through boiler equipped with a gas-liquid separator that separates absorbing liquid and vapor makes it possible to reduce the size and simplification of the equipment and increase the efficiency by heat recovery. Will be possible. The structure of the gas-liquid separator also includes a method of providing a partition plate inside,
A method of branching from the middle of the outlet pipe may be considered. When a once-through boiler is combined with an absorption refrigerator, it is necessary to satisfy the "conditions for making the concentrator a once-through boiler" so as not to deviate from the definition of the once-through boiler. The ratio of the circulating fluid amount to should be 2 or less. In a multi-tube system, all heating tubes must be riser tubes. It is necessary to plan in consideration of. In addition to the double-effect absorption refrigerator, the single-effect absorption refrigerator is combined with the once-through boiler to operate a double-effect cycle that saves energy compared to the conventional single-effect absorption refrigerator. It becomes possible. Of course, it is also possible to apply to an absorption refrigerator of triple effect type or more.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments and can be implemented with appropriate modifications. FIG. 1 shows an absorbent concentrator according to a first embodiment of the present invention, and FIG. 2 shows an example of a merging portion surrounded by a chain line circle in FIG. Reference numeral 10 denotes a once-through concentrator, which has annular upper headers (upper headers) 12 and lower headers (lower headers) 14 at upper and lower portions, and a large number of vertical risers are provided between these headers 12 and 14. A pipe 16 is disposed in a substantially cylindrical shape, and a combustion device 18, for example, a burner is provided in the upper central part. The diluted absorption liquid is introduced into the lower header 14 and concentrated by heating, and the gas-liquid mixture is supplied from the upper header 12. It is configured so that it can be taken out. Reference numeral 20 denotes a combustion chamber, and reference numeral 22 denotes a short pipe for cleaning and inspection.

The gas-liquid mixture conduit 2 is connected to the once-through concentrator 10.
A gas-liquid separator 26 is connected through the connection 4. A vapor extraction conduit 28 is connected to an upper part of the gas-liquid separator 26, and an absorption liquid extraction conduit 30 is connected to a lower part of the gas-liquid separator 26. 32 is an upper partition plate (gas-liquid separation plate), and 34 is a lower partition plate. The lower part of the gas-liquid separator 26 and the once-through concentrator 10
Is connected to the lower header 14 via an absorption liquid circulation conduit 36. 38 is a flow control valve or a throttle valve. An absorption liquid supply pipe 42 having an absorption liquid supply pump 40 is connected to the absorption liquid circulation conduit 36.

A temperature sensor 44 is provided in the vapor discharge conduit 28.
However, a liquid sensor 46 is provided at a substantially central portion on the side of the main body of the gas-liquid separator 26, and a temperature sensor 48 is provided in the absorbent extraction pipe 30. Further, fuel cutoff valves 52 and 54 are provided in a fuel supply pipe 50 connected to the combustion device 18, and the temperature sensors 44 and 48, the liquid sensor 46,
The fuel cutoff valves 52 and 54 and the absorption liquid supply pump 40 are electrically connected to the operation control panel 56 to detect the absorption liquid temperature and the vapor temperature independently or simultaneously, and when the temperatures deviate from the set temperatures, the fuel cutoff valves are turned off. A safety circuit is configured such that the fuel supply is stopped by closing the fuel tanks 52 and 54, and the fuel sensor 46 detects the decrease in the supply amount of the absorbing liquid to close the fuel cutoff valves 52 and 54 to stop the fuel supply. 58 is a compound meter and 60 is a safety valve. The outlet pipe 62 of the safety valve 60 is connected to an absorption refrigerator (vacuum vessel). Further, an interlock is assembled with the absorbent pump 40, and a double shutoff circuit is configured and incorporated so that the fuel supply is stopped even when the pump 40 is stopped.

As shown in FIGS. 2 (a) to 2 (c), the junction 64 between the absorption liquid circulation conduit 36 and the absorption liquid supply pipe 42 is connected to the absorption liquid circulation conduit 36 upstream of the junction 64.
6 or a throttle such as a valve is provided. The junction 64
As shown in FIG. 2A, the supply pipe 42 is provided in the circulation conduit 36.
2 or simply connect the supply pipe 42 to the circulation conduit 36 as shown in FIG. 2 (b), or connect the supply pipe 42 directly to the lower header 14 as shown in FIG. 2 (c). A configuration such as connection is adopted.

The absorbent concentrator 68 constructed as described above.
In, the absorbing solution, for example, a lithium bromide aqueous solution is heated and concentrated. The heated and concentrated aqueous solution and the vapor separated from the aqueous solution (for example, 1.8 kg / cm ² G) are supplied to an absorption refrigerator (vacuum vessel). As a safety measure to prevent shortage of boiler liquid, as described above, the absorption liquid temperature and steam temperature are measured individually or simultaneously, and if the temperature greatly deviates from the set temperature, the combustion is stopped and the liquid such as a float switch, level switch, etc. Equipped with a safety circuit that electrically controls the sensor to stop combustion when the sensor detects a decrease in the supply of absorbent. In addition, a double shutoff circuit is provided which interlocks with the pump 40 for supplying the absorbing liquid and stops combustion even when the pump 40 is stopped. Further, the absorption liquid supply pump 40 operates continuously. The lithium bromide aqueous solution and the vapor are absorbed and mixed in the absorption refrigerator, become a dilute solution, circulate back to the once-through concentrator 10, and return.

FIG. 3 shows an absorbent concentrate 68a according to a second embodiment of the present invention. In the present embodiment, the absorption liquid circulation conduit 36 from the lower part of the gas-liquid separator 26a is branched into an absorption liquid extraction conduit 30a. In addition, the lower partition plate in the gas-liquid separator 26 becomes unnecessary. Other configurations and operations are the same as those in the first embodiment.

FIG. 4 shows an absorption refrigerator according to a third embodiment of the present invention.
This shows a case in which an absorbent concentrator 68 according to the embodiment is combined. 72 is a vacuum pump. The illustration around the control panel is omitted. Absorbent concentrator 68
Is supplied to the heating side of the high-temperature regenerator, and the absorbing liquid from the absorbing liquid concentrator 68 is connected to the heated side of the high-temperature regenerator. In this way, a closed circuit for supplying the aqueous solution heated and concentrated by the absorbing liquid concentrator 68 and the vapor separated from the aqueous solution to the absorption refrigerator 70 (vacuum vessel) and recovering the whole amount is formed. The absorption liquid supply pump 40 (circulation pump) is operated continuously. The absorbing liquid, for example, an aqueous solution of lithium bromide and steam are mixed in the absorption refrigerator 70 to become a dilute solution and circulate back to the absorbing liquid concentrator 68. When stopped,
Both the inside of the concentrator 68 and the inside of the refrigerator 70 are evacuated. To prevent air from entering from outside during stoppage,
It is necessary to make connections by welding as much as possible.

FIG. 5 shows an absorption refrigerator according to a fourth embodiment of the present invention.
This shows a case in which the absorption liquid concentrator 68a according to the embodiment is combined. Other configurations and operations are the same as those in the third embodiment.

FIG. 6 shows an absorption refrigerator according to a fifth embodiment of the present invention, in which a single (single) effect absorption refrigerator 74 is combined with an absorption liquid concentrator 68 according to the first embodiment. ing. The illustration around the control panel is omitted. The vapor from the absorbing liquid concentrator 68 is supplied to the heating side of the regenerator, and the absorbing liquid from the absorbing liquid concentrator 68 is connected to be supplied to the heated side of the regenerator.
In this way, a closed circuit is provided in which the aqueous solution heated and concentrated by the absorbing liquid concentrator 68 and the vapor separated from the aqueous solution are supplied to the absorption refrigerator 74 (vacuum vessel) to collect the entire amount. The absorption liquid supply pump 40 (circulation pump) is operated continuously. Absorbing liquid, for example, lithium bromide aqueous solution and vapor,
The mixture is mixed in the absorption refrigerator 74 to become a dilute solution and circulates back to the absorption liquid concentrator 68. When stopped, both the inside of the concentrator 68 and the inside of the refrigerator 74 are evacuated. Pipes and other connections must be made by welding as much as possible to prevent air from entering during shutdown.

FIG. 7 shows an absorption refrigerator according to a sixth embodiment of the present invention, in which a single (single) effect absorption refrigerator 74 is combined with an absorbent concentrator 68a according to the second embodiment. ing. Other configurations and operations are the same as those in the fifth embodiment.

FIG. 8 shows an absorption refrigerator according to a seventh embodiment of the present invention, and shows the configuration shown in FIG. 4 in detail. In this embodiment, an absorber 81, a pump (dilute liquid pump) 82, a low-temperature heat exchanger 83, a low-temperature regenerator 84, a pump (intermediate liquid pump) 85, a high-temperature heat exchanger 86, a high-temperature regenerator 87, and a condenser 88 , An evaporator 89, a refrigerant pump 90, and a reverse cycle type double effect absorption refrigerator including a refrigerant pipe, a refrigerant pipe, and the like for connecting these components. And an integrated heat pump 94, an additional heat exchanger 94, and the like. In FIG. 8, the arrows attached to the solid lines indicate the flow directions of the absorbing liquid, the refrigerant liquid, and the water,
The arrows attached to the broken lines indicate the flow direction of the refrigerant vapor or the mixture of the refrigerant vapor and the condensed refrigerant (refrigerant drain).

Reference numeral 95 denotes a first bypass pipe, which is a low-temperature regenerator 84.
A part of the absorption liquid from the high-temperature heat exchanger 86 is bypassed to the concentrated absorption liquid pipe. Reference numeral 96 denotes a second bypass pipe for bypassing a part of the absorbent from the high-temperature regenerator 87 to the return concentrated absorbent pipe from the additional heat exchanger 94. 99 is a cold / hot water pump, 100
Is a cooling water pump. Note that another concentrator can be installed between the high-temperature regenerator 87 and the absorbent concentrator 68.

Next, the circulation cycle of the absorbent in the absorption refrigerator configured as described above will be described in order. First, the diluted absorption liquid whose concentration has been reduced by absorbing a large amount of refrigerant vapor in the absorber 81 is sent from the absorber 81 to the low-temperature heat exchanger 83 by the diluted liquid pump 82, and the low-temperature heat exchanger 83 After being heated, it is fed to the low-temperature regenerator 84. Then, the rare absorbing liquid is regenerated at a low temperature in the low-temperature regenerator 84, and a part of the absorbed refrigerant is released and the concentration is increased by that amount to become an intermediate-concentration intermediate absorbing liquid.

Most of the intermediate concentrated absorption liquid is sent from the low temperature regenerator 84 to the high temperature heat exchanger 86 by the intermediate absorption liquid pump 85, and is heated by the high temperature heat exchanger 86 and then supplied to the high temperature regenerator 87. Will be sent. The intermediate concentrated absorbent is regenerated at a high temperature in the high-temperature regenerator 87 and releases a part of the absorbed refrigerant to further increase the concentration to become a high-concentration concentrated absorbent. The remainder of the intermediate concentrated absorption liquid from the low-temperature regenerator 84 is supplied to the concentrated absorption liquid piping returning to the absorber 81 by bypass via a bypass pipe 95.

A part or all of the concentrated absorbent from the high-temperature regenerator 87 is supplied to the additional heat exchanger 94 by the absorbent pump 93, where it exchanges heat with the concentrated absorbent from the absorbent concentrator 68. Then, it is supplied to the absorbing liquid concentrator 68. The remaining part (may be zero) of the concentrated absorbent from the high-temperature regenerator 87 joins the absorbent pipe on the heating side from the additional heat exchanger 94 via the second bypass pipe 96.

In the absorbent concentrator 68, the concentrated absorbent heated and concentrated by the heat of combustion of the fuel is introduced into the heating side of the additional heat exchanger 94 to heat the concentrated absorbent from the high temperature regenerator 87. The high-temperature heat exchanger 86 is introduced to the heating side. The remaining part (may be zero) of the concentrated absorbent from the high-temperature regenerator 87 joins the absorbent pipe on the heating side from the additional heat exchanger 94 via the second bypass pipe 96. Absorbent concentrator 68
From the high-temperature regenerator 8 through a vapor extraction conduit 28
7, where the absorption liquid is heated and concentrated, and then the refrigerant drain is introduced into the low-temperature regenerator 84.

The refrigerant vapor from the high-temperature regenerator 87 is sent to the low-temperature regenerator 84 together with the refrigerant drain from the high-temperature regenerator 87 through a refrigerant vapor pipe 97, where the absorption liquid is heated and concentrated. The refrigerant vapor from the low-temperature regenerator 84 is introduced into the condenser 88 through the refrigerant vapor pipe 98 together with the refrigerant drain from the low-temperature regenerator 84. In some cases, the combustion exhaust gas from the absorption liquid concentrator 68 is introduced into an exhaust gas heat exchanger to heat the absorption liquid or the refrigerant and recover the retained heat of the exhaust gas.

FIG. 9 shows an absorption refrigerator according to an eighth embodiment of the present invention, and shows the configuration shown in FIG. 5 in detail. The present embodiment is a combination of the absorbent concentrator 68a and the double effect absorption refrigerator 70 shown in FIG. Other configurations and operations are the same as those of the seventh embodiment.

FIG. 10 shows an absorption refrigerator according to a ninth embodiment of the present invention, and shows the configuration shown in FIG. 6 in detail. The present embodiment is a combination of the absorbent concentrator 68 shown in FIG. 1 and a single (single) effect absorption refrigerator 74. 101 is a regenerator. Other configurations and operations are the same as those of the seventh embodiment.

FIG. 11 shows an absorption refrigerator according to a tenth embodiment of the present invention, and shows the configuration shown in FIG. 7 in detail. In the present embodiment, the absorbent concentrator 68 shown in FIG.
This is a combination of a with a single (single) -effect absorption refrigerator 74. 101 is a regenerator. Other configurations and operations are the same as those of the seventh embodiment.

The flow of the absorption liquid in the absorption liquid concentrator in the above absorption refrigerator will be described with reference to FIGS. FIG. 12 shows the flow of fluid around the gas-liquid separator 26 when the riser 16 is heated, and FIG. 13 shows the flow of fluid around the gas-liquid separator when the riser 16 is not heated. The flow of the absorbing liquid and water (steam) during normal operation (a state in which steam is generated from the upper header 12) is as follows (see FIG. 12). (1) The mixed solution of the absorbing liquid and water is supplied from the absorbing liquid supply pipe 42 to the boiler lower header 14 through the merge pipe 102 by the absorbing liquid supply pump. (2) The mixture of the absorbing liquid and water heated by the combustion heat generates steam in the riser 16, rises in the riser 16 in a gas-liquid mixture state, exits the gas-liquid mixture conduit 24, and flows out of the gas-liquid mixture 24. In the separator 26, the vapor, the unvaporized water and the absorbent are separated, and the vapor passes through a vapor extraction conduit 28 and is used as a heat source of the absorption refrigerator for heating the absorbent. (3) On the other hand, water and absorption liquid that have not been completely vaporized
Although a part of the liquid is returned to the lower header 14 through the absorbent circulation pipe 36 as recirculated liquid, most of the absorbed liquid supplied by the supply pump returns to the refrigerator side through the absorbed liquid extraction conduit 30. It is used for a cooling effect of absorbing heat from cold water in a vacuum vessel and absorbing the evaporated refrigerant (water). (4) Although the liquid is stored in the gas-liquid separator 26 and has a water level,
There is a gas-liquid mixture in the body riser 16 and there is no clear water level. That is, a pressure difference (water level difference) is generated between the gas-liquid separator 26 and the main body rising pipe 16, and a part of the water and the absorbing liquid that are not completely vaporized are recirculated as the recirculating liquid by the absorbing liquid circulating conduit 36. Circulate through. (5) When the heating in the combustion chamber is stopped, as shown in FIG. 13, the water level in the gas-liquid separator 26 and the water level in the main body rising pipe 16 become the same level, and the recirculation due to the pressure difference stops. (6) If the absorption liquid supply pump continues to operate even after the combustion stops, the absorption liquid is supplied by the pump pressure, so that the inside of the pipe is filled with the liquid. (7) Since the filled liquid tends to flow on the side with less resistance, the liquid also flows to the internal piping of the main body, but most of the liquid flows backward through the absorbent circulation pipe 36 to enter the gas-liquid separator 26 and discharge the absorbed liquid. It returns to the refrigerator side through the conduit 30.

Here, as shown in the above-mentioned Japanese Patent No. 2960805, if a check valve is attached in the middle of the communication return path (corresponding to the absorbent circulation pipe 36), the following problem occurs. . (1) Even when the pressure of the main body is not rising or when the amount of generated steam is small, such as during start-up, combustion stop, or control operation, supply all the absorbing liquid and water supplied from the pump to the main body side. become. (2) The check valve seems to be effective at first glance in order to prevent the circulating liquid from flowing back.
In any operation condition, the liquid cannot be circulated unless the inside of the ascending pipe on the main body side is filled with the absorbing liquid and the water. (3) In the case where the absorption liquid is circulated to the refrigerator side, a complete closed circuit is formed, and the absorption liquid is returned to the suction side of the absorption liquid supply pump again to form a liquid circulation cycle, the pressure condition in the main body is required. If the amount of liquid circulating in the inside does not fluctuate even if the pressure changes, the pump will cavitation when a bad condition such as insufficient circulation occurs. (4) Due to the check valve, the circulating liquid does not flow toward the absorbing liquid extraction conduit 30 unless the inside of the main body is filled with the liquid. Insufficient circulation amount is more likely to occur as much as the inside of the tube is filled with liquid compared to during operation. In particular, the gas-liquid mixture conduit 24 is supplied with liquid from the main riser 16, the upper header 1
2. Until the gas-liquid mixture conduit 24 is filled and the liquid is filled up to the gas-liquid separator 26, the liquid cannot flow into the piping returning to the refrigerator side. There is also insufficient liquid returning to the suction side. (5) Due to the check valve, if the specific operating conditions are not met, such as when burning, smooth circulation of the liquid will not be possible, and it is expected that adverse effects such as damage to the circulating pump will occur. Is hard to imagine.

The absorption liquid concentrator in the absorption refrigerator of the present invention has the following advantages because a throttle portion such as an orifice and a valve is provided without providing a check valve. (1) By adopting a method of adjusting the pressure and the flow rate by providing a resistance with a valve, an orifice or the like in the middle of the circulation conduit 36 in which a part of the absorbing liquid is recirculated, when the pressure inside the main body is low such as at the time of starting, the main body is Although the riser 16 is filled with liquid, the absorption liquid rises at the same level by flowing backward in the circulation conduit 36, so that the gas-liquid mixture conduit 24 is not filled with liquid,
Before that, the liquid can be returned quickly to the system in which the liquid returns from the absorbing liquid extraction conduit 30 to the supply pump blowing side and can be smoothly circulated, so that cavitation of the pump hardly occurs. (2) When the operation starts, the absorbing liquid and water start to circulate in a state of gas-liquid mixing in the riser 16 and steam is generated to increase the internal pressure. As described in (1) above, the liquid level Due to the difference, the liquid circulation between the gas-liquid separator 26 and the main body rising pipe 16 occurs, and the operation shifts to smooth operation. (3) During normal operation, if the liquid does not flow backward from the circulation conduit 36, sufficient vapor cannot be generated due to the liquid bypass. (4) A throttle such as a valve or an orifice is provided in the middle of the circulation conduit 36, and the steam pressure, water level difference, and throttle (resistance) inside the main body are reduced.
By the effect described above, it is possible to prevent the absorption liquid supplied under pressure from the pump from flowing backward, and it is possible to continue the smooth operation.

[0043]

As described above, the present invention has the following effects. (1) By integrally combining a once-through boiler type absorption liquid concentrator for separating the absorption liquid and the vapor and the absorption refrigerator, the apparatus can be reduced in size and simplified, and
Energy saving operation can be performed, and efficiency can be improved by heat recovery. (2) When a restricting section such as an orifice or valve is provided in the absorbent circulation pipe, the pump is supplied from the absorbent supply pump due to the effects of the vapor pressure inside the riser pipe, the water level difference (liquid level difference), and the restriction (resistance). Pressure and backflow of the supplied absorbing liquid can be prevented, and smooth operation can be continued.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an absorbent concentrator according to a first embodiment of the present invention.

FIG. 2 is an enlarged detailed view of a merging portion surrounded by a chain line circle in FIG.

FIG. 3 is a schematic configuration diagram of an absorbing liquid concentrator according to a second embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of an absorption refrigerator according to a third embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of an absorption refrigerator according to a fourth embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of an absorption refrigerator according to a fifth embodiment of the present invention.

FIG. 7 is a schematic configuration diagram of an absorption refrigerator according to a sixth embodiment of the present invention.

FIG. 8 is a systematic schematic configuration diagram of an absorption refrigerator according to a seventh embodiment of the present invention.

FIG. 9 is a systematic schematic configuration diagram of an absorption refrigerator according to an eighth embodiment of the present invention.

FIG. 10 is a systematic schematic configuration diagram of an absorption refrigerator according to a ninth embodiment of the present invention.

FIG. 11 is a systematic schematic configuration diagram of an absorption refrigerator according to a tenth embodiment of the present invention.

FIG. 12 is an explanatory cross-sectional view showing the periphery of a gas-liquid separator when a main body riser is heated.

FIG. 13 is an explanatory sectional view showing the periphery of the gas-liquid separator when the main body riser tube is not heated.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Once-through concentrator 12 Upper header 14 Lower header 16 Ascending pipe 18 Combustion device 20 Combustion chamber 22 Short pipe for cleaning and inspection 24 Gas-liquid mixture conduit 26, 26a Gas-liquid separator 28 Vapor extraction conduit 30 Absorption liquid extraction Outlet conduit 32 Upper partition plate 34 Lower partition plate 36 Absorbent liquid circulation conduit 38 Flow rate control valve or throttle valve 40 Absorbent liquid supply pump 42 Absorbent liquid supply pipe 44, 48 Temperature sensor 46 Liquid sensor 50 Fuel supply pipe 52, 54 Fuel cutoff pipe 56 Operation control panel 58 Compound meter 60 Safety valve 62 Blow-out pipe 64 Merging section 66 Orifice 68, 68a Absorbent concentrator 70 Double effect absorption refrigerator 72 Vacuum pump 74 Single (single) effect absorption refrigerator 81 Absorber 82 Rare liquid pump 83 Low temperature heat exchanger 84 Low temperature regenerator 85 Intermediate liquid pump 86 High temperature heat exchanger 87 High temperature regeneration 88 condenser 89 evaporator 90 the refrigerant pump 93 absorbing pump 94 additional heat exchanger 95, 96 bypass pipe 97 and 98 the refrigerant vapor pipe 99 hot and cold water pump 100 coolant pump 101 regenerator 102 merging pipe

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Masumi Ota 1000 Aochi-cho, Kusatsu-shi, Shiga Kawashige Refrigerating and Heating Industry Co., Ltd. Shiga Plant (56) References JP-A-60-134172 (JP, A) JP-A Sho JP-A-5-159553 (JP, A) JP-A-5-99537 (JP, A) JP-A-6-201209 (JP, A) JP-A-9-503285 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25B 15/00 102 F25B 15/00 303 F25B 33/00

Claims (9)

(57) [Claims] 1. An upper header and a lower header are provided with annular headers, a number of risers are provided between the headers, a combustion device is provided at the center of the upper part, and the absorption liquid is introduced into the lower header to heat and concentrate. A once-through concentrator configured to take out the gas-liquid mixture from the upper header, a gas-liquid separator connected to the once-through concentrator via a gas-liquid mixture conduit, and a top-end connected to the gas-liquid separator. A vapor extraction conduit connected to the lower part of the gas-liquid separator, an absorption liquid circulation conduit connecting the lower part of the gas-liquid separator and the lower header of the once-through concentrator, An absorbent supply pipe having an absorbent supply pump connected to the absorbent circulation pipe. 2. The absorbent concentrator according to claim 1, wherein a throttle section is provided in the absorbent circulating conduit upstream of the junction of the absorbent circulating conduit and the absorbent supplying pipe. 3. The absorbent concentrator according to claim 2, wherein the throttle is an orifice or a valve. 4. A temperature sensor is provided in the vapor extraction conduit, a liquid sensor is provided substantially in the center of the main body of the gas-liquid separator, and a temperature sensor is provided in the absorption liquid extraction conduit, and connected to the combustion device. The fuel supply pipe is provided with a fuel cutoff valve, and the two temperature sensors, the liquid sensor, the fuel cutoff valve, and the absorption liquid supply pump are electrically connected to the operation control panel, so that the temperature of the absorption liquid and the temperature of the vapor can be measured independently or At the same time, if the temperature deviates from the set temperature, the fuel cutoff valve is closed and the fuel supply is stopped.If the decrease in the supply amount of the absorbing liquid is detected by the liquid sensor, the fuel cutoff valve is closed and the fuel supply is stopped. The absorbent concentrate according to claim 1, 2 or 3, wherein a circuit is configured. 5. The absorbent concentrator according to claim 4, wherein an interlock is provided with the absorbent supply pump, and a double shutoff circuit is configured to stop the fuel supply even when the pump is stopped. 6. A high-temperature regenerator comprising a double-effect absorption refrigerator and an absorbent concentrate according to any one of claims 1 to 5, wherein steam from the absorbent concentrate is passed through a vapor discharge conduit. The absorption liquid from the absorption refrigerator is connected to the heating side of the high-temperature regenerator through the absorption liquid extraction conduit, so that the absorption liquid from the absorption liquid concentrator can be supplied to the heating side. Characterized by being connected so as to be supplied to a lower header of an absorbent concentrate through an absorbent supply pipe. 7. A regenerator comprising a single-effect absorption refrigerator and the absorbent concentrator according to any one of claims 1 to 5, wherein the steam from the absorbent concentrator is heated via a vapor extraction conduit. The absorption liquid from the absorption refrigerating machine is connected to the heated side of the regenerator through the absorption liquid extraction conduit, and the absorption liquid from the absorption refrigerator is absorbed into the absorption liquid. An absorption refrigerator using an absorption liquid concentrator, which is connected so as to be able to supply to a lower header of the absorption liquid concentrator via a supply pipe. 8. A low-temperature heat exchanger comprising:
It is configured to circulate to the absorber through the low-temperature regenerator, high-temperature heat exchanger, high-temperature regenerator, high-temperature heat exchanger, and low-temperature heat exchanger. In a reverse cycle steam absorption refrigerator equipped with a bypass pipe that bypasses part of the liquid to the concentrated absorption liquid pipe returning to the absorber, the absorption liquid piping returning from the high-temperature regenerator to the high-temperature heat exchanger, A solution supply means for extracting at least a part of the absorbent solution and supplying the solution to the lower header of the absorbent concentrate according to any one of claims 1 to 5, and heating and concentrating the absorbent solution from the solution supply means. An absorption liquid concentrator is connected in series, and heat exchange between the concentrated absorption liquid from the high temperature regenerator and the absorption liquid heated and concentrated by the absorption liquid concentrator is performed between the solution supply means and the absorption liquid concentrator. Set up a heat exchanger and heat with an absorbent concentrator The absorption liquid concentrator and the additional heat exchanger are connected by an absorption liquid extraction conduit so as to return the condensed absorption liquid to the heating side of the additional heat exchanger. An absorption liquid concentrator and a high-temperature regenerator connected by a vapor extraction conduit so that refrigerant vapor evaporated from the liquid is supplied to the high-temperature regenerator as a heating source; refrigerator. 9. A low-temperature heat exchanger comprising:
In a steam absorption refrigerator configured to circulate through a regenerator and a low-temperature heat exchanger to an absorber, at least a part of the absorbent from the regenerator is connected to an absorbent pipe returning from the regenerator to the low-temperature heat exchanger. A solution supply means for extracting and supplying to the lower header of the absorbent concentrate according to any one of claims 1 to 5, and the absorbent concentrate for heating and concentrating the absorbent from the solution supply means in series. And an additional heat exchanger for heat exchange between the concentrated absorbent from the regenerator and the absorbent heated and concentrated by the absorbent concentrator is provided between the solution supply means and the absorbent concentrate. The absorption liquid concentrator and the additional heat exchanger are connected by an absorption liquid extraction conduit so that the absorption liquid heated and concentrated by the concentrator is returned to the heating side of the additional heat exchanger. The refrigerant vapor evaporated from the concentrated absorption liquid is used as a heat source for the regenerator. As supplied, the absorption refrigerating machine and the absorption liquid concentrator and regenerator using an absorbing liquid concentrator, characterized in that connected with steam extraction conduits.