JP4390267B2 - Single double effect absorption refrigerator and operation control method thereof - Google Patents

Description

  The present invention relates to a single double-effect absorption refrigerator (including an absorption chiller / heater).

  As this type of absorption refrigerator, for example, as shown in FIG. 5, a high-temperature regenerator 5 that heats the absorption liquid by using combustion heat generated by the gas burner 4 as a heat source and evaporates and separates the refrigerant is supplied from the high-temperature regenerator 5. The low-temperature regenerator 6 is a double-effect regenerator that heats the absorption liquid by using the refrigerant vapor as a heat source and evaporates and separates the refrigerant, and the refrigerant vapor supplied from the low-temperature regenerator 6 is condensed in parallel with the low-temperature regenerator 6. The absorption liquid is heated by using a relatively low temperature hot waste water of, for example, about 80 ° C. supplied from the condenser 7 of the double effect condenser, the cogeneration device, etc. via the low heat source supply pipe 28, and the refrigerant is evaporated. A low heat source regenerator 9 of a single effect regenerator to be separated, a condenser 10 of a single effect condenser which is provided in parallel to the low heat source regenerator 9 and condenses the refrigerant vapor supplied from the low heat source regenerator 9, a condenser 7 And supplied from condenser 10 An evaporator 1 for evaporating the refrigerant liquid to be evaporated, an absorber 2 for absorbing the refrigerant vapor evaporated in the evaporator 1 by the concentrated absorbent supplied from the low temperature regenerator 6, a rare absorbent pump P1, an intermediate absorbent pump P3, A single double-effect absorption refrigerator 100X equipped with a refrigerant pump P5 and the like is well known (see, for example, Patent Document 1).

  In the figure, 12 is a low-temperature heat exchanger, 13 is a high-temperature heat exchanger, 26 is a brine pipe for circulating and supplying cooling or heating to a heat load (not shown), 27 is a cooling water pipe, and 28A is low. A bypass pipe 28 </ b> B provided in the heat source supply pipe 28 is a three-way valve provided in the low heat source supply pipe 28.

  In the single double-effect absorption refrigerator 100X having the above-described configuration, the low-temperature heat source regenerator 9 that is arranged in parallel with the condenser 10 to which the cooling water is supplied and is maintained at a low temperature has a hot drainage of the heat source. Even when not supplied, the rare absorbent is supplied from the absorber 2 by the rare absorbent pump P1. Further, since the temperature of the rare absorbent flowing into the low heat source regenerator 9 is higher than the saturation temperature in the low heat source regenerator 9, there is a problem that the temperature is reduced by self-flashing and heat loss occurs.

Further, when the hot water drainage of the heat source leaks into the low heat source regenerator 9 when the rare absorbent in the absorber 2 is not circulated and supplied to the low heat source regenerator 9 by the rare absorbent pump P1, the leaked temperature There is also a problem that the absorbing solution in the low heat source regenerator 9 is heated by the waste water, and the absorbing solution may be excessively concentrated and crystallized.
Japanese Patent Laid-Open No. 06-341729 (FIG. 1)

  Therefore, the rare absorption liquid flowing into the low heat source regenerator from the absorber does not self-flush, and the absorption liquid is not excessively heated and concentrated in the low heat source regenerator to be crystallized. It was necessary to solve this, and the solution was an issue.

  In order to solve the above-mentioned problems of the prior art, the present invention provides an evaporator absorber cylinder containing an evaporator and an absorber, a low-temperature regenerator condenser cylinder containing a low-temperature regenerator and a condenser, a hot waste water, etc. Connect a low heat source regenerator condenser body, a high temperature regenerator, a low temperature heat exchanger, a high temperature heat exchanger, a rare absorbent pump, an intermediate absorbent pump, etc. In the single double-effect absorption refrigerator that constitutes,

  A second rare absorption liquid pump is provided on the low heat source regenerator side of the absorption liquid pipe connected to the absorber and the low heat source regenerator through the rare absorption liquid pump and the low temperature heat exchanger, and the second rare absorption liquid pump is provided. The upstream side of the absorption liquid pump communicates with the upstream side of the intermediate absorption liquid pump of the absorption liquid pipe connecting the low heat source regenerator and the high temperature regenerator through the intermediate absorption liquid pump, and the heat source fluid is connected to the low heat source regenerator. Is a refrigerating machine characterized by adopting a dripping liquid film structure in which the inside of the heat transfer pipe flows and the absorbing liquid is dropped outside the pipe,

  Alternatively, a low-heat source regenerator condenser body is connected to a cooling fluid pipe routed through the inside of the condenser, and a detour that bypasses the inside of the condenser and a resistance increase that increases the flow resistance of the detour And a flow path selecting means for selecting whether the cooling fluid in the cooling fluid conduit flows through the condenser or the detour. .

  According to the first, third, and fourth aspects of the invention, when the inside of the low heat source regenerator is at a low temperature, the rare absorbent discharged from the absorber bypasses the low heat source regenerator and flows directly into the high temperature regenerator. Therefore, the rare absorption liquid does not self-flash in the low heat source regenerator. As a result, it has become possible to prevent the occurrence of heat loss, which has been a problem with conventional devices.

  The low heat source regenerator employs a dropping liquid film structure, and the heat transfer tube in the low heat source regenerator is not buried in the absorbent, so the operation of the second rare absorbent pump is stopped. Even when hot wastewater is supplied to the heat transfer tubes in the low heat source regenerator from a cogeneration system, the absorption liquid is heated and concentrated in the low heat source regenerator and crystallizes. There is no inconvenience.

  According to the invention of claim 2, when the heat source fluid at a predetermined temperature is not supplied to the low heat source regenerator from a cogeneration system or the like, the cooling water is prevented from flowing into the condensers arranged in parallel with the low heat source regenerator. Therefore, even if the rare absorption liquid discharged from the absorber flows into the low heat source regenerator, the rare absorption liquid remains in the low heat source regenerator. In self-flash. Therefore, in the invention of claim 2 as well, it has become possible to prevent the occurrence of heat loss, which has been a problem with conventional devices.

  In addition, since the cooling fluid path that passes through the inside of the condenser of the low heat source regenerator condenser and the bypass path resistance that bypasses the inside of the condenser are provided approximately the same, the cooling fluid is There is no difference in flow rate when flowing through the condenser of the low heat source regenerator condenser cylinder and when flowing through the condenser. Therefore, even if the flow path of the cooling fluid is switched, there is no difference in the cooling action of the cooling fluid in the evaporator absorber cylinder and the low temperature regenerator condenser cylinder, so that fluctuations in refrigeration performance can be suppressed.

  Evaporator absorber cylinder containing the evaporator and absorber, low temperature regenerator condenser cylinder containing the low temperature regenerator and condenser, low heat source regenerator and condenser using the hot drain as a heat source. Low heat source regenerator Rare absorption in a single-double-effect absorption refrigerator configured by connecting a condenser cylinder, high temperature regenerator, low temperature heat exchanger, high temperature heat exchanger, rare absorption liquid pump, intermediate absorption liquid pump, etc. A second rare absorption liquid pump is provided on the low heat source regenerator side of the absorption liquid pipe connected with the absorber and the low heat source regenerator via the liquid pump and the low temperature heat exchanger, and the second rare absorption liquid is provided. The heat source fluid is transferred to the low heat source regenerator through communication between the upstream side of the pump and the intermediate absorption liquid pump upstream side of the absorption liquid pipe connecting the low heat source regenerator and the high temperature regenerator via the intermediate absorption liquid pump. While adopting a dripping liquid film structure in which the absorption liquid is dripped outside the pipe, The operation / stop of the rare absorbent pump 2 is controlled based on the temperature of the heat source flowing into or discharged from the low heat source regenerator and the temperature of the brine flowing into or discharged from the evaporator. The rotation speed of the rare absorption liquid pump No. 2 was controlled based on the temperature of the brine flowing into or discharged from the evaporator.

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. For easy understanding, parts having the same functions as those described with reference to FIG.

  FIG. 1 is an explanatory view showing a first embodiment of the present invention. A single double-effect absorption refrigerator 100 illustrated in FIG. 1 is an evaporator absorber cylinder 3 in which an evaporator 1 and an absorber 2 are housed. A high-temperature regenerator 5 having a gas burner 4, a low-temperature regenerator 6, a condenser 7 arranged in parallel with the low-temperature regenerator 6, a low-temperature regenerator condenser body 8 containing the low-temperature regenerator 6 and the condenser 7, Low heat source regenerator 9 using waste water as a heat source, condenser 10 provided in parallel with low heat source regenerator 9, low heat source regenerator condenser body 11 containing low heat source regenerator 9 and condenser 10, low temperature heat Exchanger 12, high-temperature heat exchanger 13, refrigerant drain heat recovery unit 14, brine pipe 26 through which brine (for example, water) flows, cooling water pipe 27, low heat source supply pipe 28, first rare absorbent pump P1, second Rare absorbent pump P2, intermediate absorbent pump P3, concentrated absorbent pump P4, refrigerant pump P5, etc. With which they are connected by piping as shown. Moreover, the code | symbol C is a controller of the single double effect absorption refrigerator 100. FIG.

  That is, in the single double-effect absorption refrigerator 100 of the first embodiment of the present invention, the rare absorption liquid reservoir formed in the lower part of the absorber 2 and the gas phase part of the low heat source regenerator 9 are connected. A first rare absorbent pump P1 is provided upstream of the rare absorbent pipe 15 and a second rare absorbent pump P2 is provided downstream.

  The discharge side of the first rare absorbent pump P1, that is, the downstream side of the rare absorbent pipe 15 passes through the solution cooling absorber 2A provided on the upper side of the absorber 2, and then the low-temperature heat exchanger 12 is It branches into the rare absorption liquid pipe 15A that intervenes and the rare absorption liquid pipe 15B that the refrigerant drain heat recovery unit 14 interposes, and then merges and is connected to the suction side, that is, the upstream side of the second rare absorption liquid pump P2. The downstream end is connected to a spreader 9 </ b> A disposed at the upper part in the low heat source regenerator 9.

  Further, an intermediate absorption liquid pipe 16 that connects the upstream side of the second rare absorption liquid pump P2, the intermediate absorption liquid reservoir formed at the lower part of the low heat source regenerator 9, and the gas phase part of the high temperature regenerator 5. The intermediate absorption liquid pump P3 is connected to the upstream side by a bypass pipe 17.

  Further, a concentrated absorbent liquid pipe 18 that connects the absorbent reservoir of the low temperature regenerator 6 and the gas phase part of the solution cooled absorber 2A is piped through the concentrated absorbent pump P4 and the low temperature heat exchanger 12, and is concentrated. The upstream side of the absorption liquid pump P4 and the downstream side of the low-temperature heat exchanger 12 are connected by a bypass pipe 19.

  The refrigerant drain heat recovery unit 14 is provided such that the refrigerant is heated and condensed by the low-temperature regenerator 6, and the refrigerant drain introduced into the condenser 7 is supplied via the refrigerant drain pipe 20. Yes.

  Further, in the low heat source regenerator 9 of the low heat source regenerator condenser 11, a heat transfer tube 9B to which a low heat source supply pipe 28 is connected is installed below the spreader 9A, and the intermediate absorption liquid pipe 16 is a low heat source regenerator. It is connected to the bottom part of the vessel 9.

  Therefore, the warm wastewater supplied from the low heat source supply pipe 28 in the process of dripping the rare absorbent which is transported from the absorber 2 by the rare absorbent pumps P1 and P2 and sprayed on the heat transfer pipe 9B from the spreader 9A. It is heated by heat. Then, the absorption liquid concentrated by evaporating and separating the refrigerant and accumulated at the bottom is sent to the high-temperature regenerator 5 through the intermediate absorption liquid pipe 16.

  The second rare absorbent pump P2 provided in the rare absorbent pipe 15 is driven by, for example, an inverter motor (not shown), and is provided at the low heat source regenerator 9 outlet side of the low heat source supply pipe 28. Based on the warm drain outlet temperature T1 detected by the provided temperature sensor S1, the controller C performs control as shown in FIG.

  That is, when the warm drain outlet temperature T1 detected by the temperature sensor S1 is lower than the set temperature 70 ° C., for example, the operation of the second rare absorbent pump P2 is stopped. The second rare absorbent pump P2 is controlled by the controller C so as to start.

  Further, the start / stop of the second rare absorbent pump P2 is also controlled by the controller C as shown in FIG. That is, when the brine outlet temperature T2 detected by the temperature sensor S2 provided on the outlet side of the evaporator 1 of the brine pipe 26 is lower by 2 ° C. or more than the set temperature SP (for example, 7 ° C.), the second rare absorbent pump P2 is operated. And the second rare absorbent pump P2 is also controlled to start when the temperature reaches the set temperature SP-1.5 ° C. or higher during operation stop.

  Further, the second rare absorbent pump P2 is also controlled by the controller C as shown in FIG. That is, when the brine outlet temperature T2 detected by the temperature sensor S2 is, for example, 1 ° C. or more lower than the set temperature SP, the frequency of the drive power supplied to the second rare absorbent pump P2 is minimized, and for example, 1 ° C. from the set temperature SP. When the frequency is higher than this, the frequency of the drive power supply supplied to the second rare absorbent pump P2 is maximized, and when the temperature sensor S2 indicates the temperature in between, a frequency proportional to the temperature is supplied to provide the second rare absorbent pump P2. The rotational speed of P2 is controlled.

  Note that when any of the temperature sensors S1 and S2 detects the temperature at which the operation of the second rare absorbent pump P2 is to be stopped, the controller C detects the second regardless of the temperature detected by the other temperature sensor. Control is performed to stop the operation of the rare absorbent pump P2.

  Therefore, in the single double effect absorption refrigerator 100 of the first embodiment of the present invention, the low heat source regenerator 9 of the low heat source regenerator condenser body 11 is connected to the cogeneration system via the low heat source supply pipe 28. Normally, for example, warm wastewater of about 80 ° C. always flows in, but the warm wastewater flowing into the low heat source regenerator 9 through the low heat source supply pipe 28 when the cogeneration system or the like is started up or stopped. When the temperature is low or there is no inflow of warm wastewater, and therefore the temperature of the warm wastewater detected by the temperature sensor S1 falls below the set temperature of 70 ° C., the operation of the second rare absorbent pump P2 is stopped.

  Therefore, a part of the rare absorbent discharged from the absorber 2 to the rare absorbent pipe 15 is heat-exchanged with the concentrated absorbent in the low-temperature heat exchanger 12 and the temperature rises, and the remainder is refrigerant in the refrigerant drain heat recovery unit 14. The temperature rises by exchanging heat with the drain and bypasses the low heat source regenerator 9 and flows directly into the high temperature regenerator 5, so that it does not self-flush in the low heat source regenerator 9, and the conventional one shown in FIG. The heat loss as in the case of the single double effect absorption refrigerator 100X is eliminated. In addition, the temperature of the warm waste water that circulates to the cogeneration system or the like via the low heat source supply pipe 28 does not decrease too much.

  In addition, since the heat transfer tube 9B of the low heat source regenerator 9 is not structured to be buried in the absorption liquid, the cogeneration system may be connected to the heat transfer pipe 9B when the operation of the second rare absorption liquid pump P2 is stopped. Even when warm wastewater or the like serving as a heat source is supplied from the low heat source supply pipe 28, the absorption liquid is excessively heated and concentrated in the low heat source regenerator 9 to cause crystallization. It does not occur.

  Further, in the single double effect absorption refrigerator 100 of the first embodiment of the present invention, the controller C is based on the brine outlet temperature T2 detected by the temperature sensor S2 of the rotation speed of the second rare absorbent pump P2. Therefore, stable cooling can be provided.

  Furthermore, in the single double-effect absorption refrigerator 100 of the first embodiment of the present invention, the rare absorbent in the absorber 2 is removed from the low heat source regenerator 9 by the start / stop control of the second rare absorbent pump P2. Therefore, it is necessary to provide the second rare absorption liquid pump P2 and the bypass pipe 17. However, in the conventional single double effect absorption refrigerator 100X, the low heat source supply pipe 28 is required. Since the bypass pipe 28A and the expensive three-way valve 28B provided in the above can be omitted, the cost can be reduced.

  In the single double-effect absorption refrigerator 100 according to the first embodiment of the present invention, the combustion exhaust gas generated by the gas burner 4 is exhausted via the first and second waste heat recovery units 23 and 24. In the first waste heat recovery unit 23, the waste heat retained in the combustion exhaust gas is recovered by the intermediate absorption liquid flowing into the high temperature regenerator 5, and the second waste heat recovery unit 24 supplies the gas burner 4 with the waste heat. The waste heat possessed by the combustion exhaust gas is recovered by the supplied combustion air, the temperature of the intermediate absorption liquid flowing into the high-temperature regenerator 5 and the combustion air supplied to the gas burner 4 is increased, and the gas burner 4 burns. The fuel consumption is suppressed.

A second embodiment of the present invention will be described with reference to FIG.
The single double effect absorption refrigerator 100A of the second embodiment of the present invention shown in FIG. 4 is provided in the single double effect absorption refrigerator 100 of the first embodiment of the present invention shown in FIG. The installation of the second rare absorption liquid pump P2 and the bypass pipe 17 is omitted. Instead, the cooling water pipe 27 is provided with a bypass pipe 27A and a three-way valve 27B, and the cooling water flowing in the cooling water pipe 27 is supplied to the low heat source. In the regenerator condenser body 11, it can flow to the condenser 10 arranged in parallel with the low heat source regenerator 9, or can flow around the condenser 10.

  The bypass pipe 27A is provided with an orifice 27C for increasing the flow path resistance of the bypass pipe 27A so as to be substantially the same as the resistance of the flow path passing through the condenser 10.

  Therefore, also in the single-double-effect absorption refrigerator 100A of the second embodiment, when the warm waste water of a predetermined temperature does not flow into the low heat source regenerator 9, the three-way valve 27B is operated and the cooling water is condensed into the condenser 10 Therefore, since the temperature in the low heat source regenerator 9 provided in parallel with the condenser 10 does not greatly decrease, the rare absorbing liquid pipe 15 is absorbed from the absorber 2. Even if the low temperature heat exchanger 12 and the refrigerant drain heat recovery unit 14 exchange heat and rise in temperature and flow in, the rare absorption liquid does not self-flush in the low heat source regenerator 9, and FIG. The heat loss as in the conventional single double effect absorption refrigerator 100X shown is eliminated.

  In addition, since the orifice 27C is installed in the bypass pipe 27A, the flow path resistance of the bypass pipe 27A and the resistance of the flow path through the condenser 10 are substantially the same, so that the cooling water passes through the condenser 10. Therefore, there is no difference in the flow rate between when it flows and when it flows via the bypass pipe 27A. Therefore, even if the flow path of the cooling water is switched, the cooling action of the cooling water in the evaporator absorber cylinder 3 and the low-temperature regenerator condenser cylinder 8 does not vary, so that stable refrigeration performance can be obtained.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit described in the claims.

  For example, the solution cooling absorber 2A provided in the absorber 2 is not necessarily provided. The cooling water pipe 27 can also be configured such that the cooling water branches and flows to the absorber 2 and the condensers 6 and 10.

  The temperature sensor S1 is provided on the low heat source regenerator 9 inlet side of the low heat source supply pipe 28, and the temperature sensor S1 detects the temperature of the hot wastewater flowing into the low heat source regenerator 9 through the low heat source supply pipe 28. It is also possible to configure the controller C to control the start / stop of the second rare absorbent pump P2 based on the temperature.

  The temperature sensor S2 is provided on the inlet side of the evaporator 1 of the brine pipe 26, the temperature of the brine flowing into the evaporator 1 through the brine pipe 26 is detected by the temperature sensor S2, and the controller C is based on the temperature. It is also possible to control the start / stop of the second rare absorbent pump P2 and its rotational speed.

It is explanatory drawing which shows the structure of the single double effect absorption refrigerator of a 1st Example. It is explanatory drawing which shows the example of control of a 2nd rare absorption liquid pump. It is explanatory drawing which shows the other control example of a 2nd rare absorption liquid pump. It is explanatory drawing which shows the structure of the single double effect absorption refrigerator of a 2nd Example. It is explanatory drawing which shows a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Evaporator 2 Absorber 3 Evaporator absorber cylinder 5 High temperature regenerator 6 Low temperature regenerator 7 Condenser 8 Low temperature regenerator condenser cylinder 9 Low heat source regenerator 9A Sprinkler 9B Heat transfer tube 10 Condenser 11 Low heat source regenerator condensation Body 12 Low temperature heat exchanger 13 High temperature heat exchanger 14 Refrigerant drain heat recovery device 15, 15A, 15B Rare absorption liquid pipe 16 Intermediate absorption liquid pipe 17 Bypass pipe 20 Refrigerant drain pipe 26 Brine pipe 27 Cooling water pipe 27A Bypass pipe 27B Three-way Valve 27C Orifice 28 Low heat source supply pipe 28A Bypass pipe 28B Three-way valve C Controller P1 First rare absorbent pump P2 Second rare absorbent pump P3 Intermediate absorbent pump P4 Concentrated absorbent pump P5 Refrigerant pump S1, S2 Temperature Sensor 100, 100A, 100X Single double effect absorption refrigerator

Claims (4)

  Evaporator absorber cylinder containing the evaporator and absorber, low temperature regenerator condenser cylinder containing the low temperature regenerator and condenser, low heat source regenerator and condenser using the hot drain as a heat source. Low heat source regenerator Rare absorption in a single-double-effect absorption refrigerator configured by connecting a condenser cylinder, high temperature regenerator, low temperature heat exchanger, high temperature heat exchanger, rare absorption liquid pump, intermediate absorption liquid pump, etc. A second rare absorption liquid pump is provided on the low heat source regenerator side of the absorption liquid pipe connected with the absorber and the low heat source regenerator via the liquid pump and the low temperature heat exchanger, and the second rare absorption liquid is provided. The heat source fluid is transferred to the low heat source regenerator through communication between the upstream side of the pump and the intermediate absorption liquid pump upstream side of the absorption liquid pipe connecting the low heat source regenerator and the high temperature regenerator via the intermediate absorption liquid pump. It features a dripping liquid film structure that flows inside the heat pipe and the absorbent is dripped outside the pipe. Single double-effect absorption chillers to be.   Evaporator absorber cylinder containing the evaporator and absorber, low temperature regenerator condenser cylinder containing the low temperature regenerator and condenser, low heat source regenerator and condenser using the hot drain as a heat source. Low heat source regenerator Low heat source in single-double-effect absorption refrigerator constructed by connecting pipes to condenser body, high temperature regenerator, low temperature heat exchanger, high temperature heat exchanger, rare absorption liquid pump, intermediate absorption liquid pump, etc. A cooling fluid pipe routed through the inside of the condenser of the regenerator condenser body, a detour that bypasses the interior of the condenser, a resistance increasing means that increases the flow resistance of the detour, and cooling A single-double-effect absorption refrigerator having a flow path selecting means for selecting whether a cooling fluid in a fluid pipe flows in the condenser or the detour.   The single double-effect absorption refrigerator according to claim 1, wherein the operation / stop of the second rare absorption liquid pump flows into the low heat source regenerator or the temperature of the heat source discharged from the low heat source regenerator and into the evaporator. Or the operation control method characterized by controlling based on the temperature of the brine discharged from the evaporator.   The single-double-effect absorption refrigerator according to claim 1, wherein the rotational speed of the second rare absorbent pump is controlled on the basis of the temperature of the brine flowing into or discharged from the evaporator. Control method.

Images