JP2006017323A - Triple-effect absorption chiller/heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a triple-effect absorption chiller/heater for securing the performance of a gas-liquid separator during a time from start to a steady-state operation while preventing unloaded heating due to the short supply of solution to heat transfer tubes. <P>SOLUTION: The triple-effect absorption chiller/heater comprises an once-through high temperature regenerator 1 having a lower header 3, an upper header 2, the plurality of heat transfer tubes 4, a combustor 6, and the gas-liquid separator 8. The gas-liquid separator 8 has the upper part out of which refrigerant vapor flows and the lower part out of which rich solution flows. The triple-effect absorption chiller/heater also has a float box 18 which forms the liquid level of the rich solution flowing from the gas-liquid separator 8, a float valve 19 for adjusting the amount of dilute solution into the high temperature regenerator 1 depending on the liquid level of the rich solution in the float box 18, and a communication tube 20 communicating the lower header 3 with a vapor-phase portion of the float box 18 and having a liquid level detector 25 for detecting the liquid level of the high temperature regenerator 1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a triple effect absorption chiller / heater, and is particularly suitable for a triple effect absorption chiller / heater used in an air conditioner or the like.

  As a conventional technique, for example, in the triple effect absorption chiller / heater of Patent Document 1, a high-temperature regenerator having a once-through boiler structure is provided with an annular upper header (upper header) and a lower header (lower header) at the upper and lower portions. A large number of vertical ascending pipes are arranged between these headers in a substantially cylindrical shape, and a combustion device is provided in the upper central part. A dilute solution is introduced into the lower header and concentrated by heating. It is configured to take out the gas-liquid mixture. In addition, a gas-liquid separator is connected to the upper header via a gas-liquid mixture conduit, a vapor extraction conduit is connected to the upper portion of the gas-liquid separator, and an absorption liquid is connected to the lower side of the gas-liquid separator. The extraction conduit is connected, the lower part of the gas-liquid separator and the lower header are connected by the absorption liquid circulation conduit, the absorption liquid supply pipe is connected to the absorption liquid circulation conduit or the lower header, and the gas-liquid separator Is equipped with a vertical pipe connected via an upper liquid inlet / outlet pipe and a lower inlet / outlet pipe, a float containing a magnet is floated on the liquid level in the vertical pipe, and a high liquid level detection switch and a low liquid level detection are provided on the outer surface of the vertical pipe. A switch is provided. In the above prior art, in order to prevent emptying of the high-temperature regenerator, the liquid level becomes high at the time of start-up, so that the combustion operation is not started unless the high level liquid level detection switch is detected. A test operation mode is provided to confirm that the low and low liquid level detection switch is normally detected.

Japanese Patent Laying-Open No. 2003-227762 (page 12, FIGS. 1 to 6)

  In the above prior art, the high level liquid level detection switch and the low level liquid level detection switch in which the lower pipe header of the high temperature regenerator and the bottom part of the gas-liquid separator are communicated and the liquid level in the heat transfer pipe of the high temperature regenerator is provided in the vertical pipe. And a high liquid level detection switch for preventing emptying is provided in the vicinity of the tube sheet of the upper header of the high temperature regenerator.

  At the start-up, the liquid level in the gas-liquid separator rises and the gas phase part for gas-liquid separation is limited to a very small size, the temperature of the solution supplied to the high-temperature regenerator is as low as the outside air temperature, and the pressure is Since the pressure is about 1/100 atm, the density of the refrigerant vapor generated in the riser after being heated by the combustion device is as small as about 1/200 at the rated operation, and the speed of the refrigerant vapor flowing into the gas-liquid separator is Since the liquid level in the gas-liquid separator is greatly increased, the solution is introduced from the stirred liquid level together with the refrigerant vapor to the intermediate temperature regenerator from the vapor extraction conduit.

  In addition, during the subsequent operation, the liquid level in the gas-liquid separator decreases, and even if the liquid level position is balanced by the combustion amount in the combustion device and the circulation rate of the solution, the liquid level in the gas-liquid separator is always constant. Since the liquid level exists, the liquid level in the gas-liquid separator is disturbed by the vapor flow of the refrigerant vapor mixed with the solution flowing from the upper header of the high-temperature regenerator into the gas-liquid separator during operation. The solution is likely to be accompanied by the refrigerant vapor introduced into the refrigerant, and the solution is mixed into the refrigerant. If the solution is mixed into the refrigerant, the evaporation temperature of the refrigerant in the evaporator rises, causing a decrease in performance, which hinders the operation of the triple effect absorption chiller / heater. In addition, in order to ensure the gas-liquid separation performance while forming the liquid level in the gas-liquid separator, it is necessary to ensure a sufficient gas phase portion even when the liquid level at the start-up rises. The vessel becomes large, and the degree of freedom is limited to the equipment arrangement of the triple effect absorption chiller / heater.

  Moreover, in the said prior art, the operation method in the case of repeating combustion and a stop of a combustion apparatus at the time of partial load operation is not described.

  The object of the present invention is to ensure the performance of the gas-liquid separator from start-up to steady operation, and to produce air that is caused by insufficient supply of the solution to the plurality of heat transfer tubes connected to the lower header and the upper header. It is providing the triple effect absorption cold / hot water machine which can prevent.

  In order to achieve the above object, the present invention provides a high temperature regenerator, a medium temperature regenerator, a low temperature regenerator, a condenser, an evaporator, an absorber, a high temperature heat exchanger, a medium temperature heat exchanger, a low temperature heat exchanger, and a solution circulation. A solution / refrigerant circulation circuit is configured by connecting a pump, a solution spray pump, and a refrigerant pump with a solution pipe and a refrigerant pipe. The high-temperature regenerator includes a lower header into which a dilute solution flows, and a mixture of concentrated solution and refrigerant vapor. From the upper header, a plurality of heat transfer tubes connecting the lower header and the upper header, a combustion device for circulating a combustion gas outside the plurality of heat transfer tubes, and the upper header The flow-through high temperature regenerator includes a gas-liquid separator that separates the concentrated mixture solution and the refrigerant vapor, and the gas-liquid separator allows the refrigerant vapor to flow out from above and In the triple effect absorption chiller / heater that flows out from the bottom A float box for forming a liquid level of the concentrated solution flowing out from the gas-liquid separator, and a float valve for adjusting a dilute solution amount to the high temperature regenerator according to a liquid level of the concentrated solution in the float box; And a communication pipe provided with a liquid level detector for detecting the liquid level of the high temperature regenerator as well as communicating the lower header and the gas phase part of the float box.

  In order to achieve the above object, the present invention provides a high temperature regenerator, a medium temperature regenerator, a low temperature regenerator, a condenser, an evaporator, an absorber, a high temperature heat exchanger, a medium temperature heat exchanger, a low temperature heat exchanger, A solution circulation pump, a solution spray pump, and a refrigerant pump are connected by a solution pipe and a refrigerant pipe to form a solution / refrigerant circulation circuit. The high temperature regenerator includes a lower header into which a dilute solution flows, a concentrated solution and a refrigerant vapor. An upper header that flows out the mixture of the above, a plurality of heat transfer tubes that connect the lower header and the upper header, a combustion device that circulates combustion gas outside the plurality of heat transfer tubes, and the upper tube It is composed of a once-through high temperature regenerator equipped with a gas-liquid separator that separates the concentrated solution of the mixture flowing out from the header and the refrigerant vapor. Triple effect absorption cold / hot water that drains solution from the bottom A float box that forms a liquid level of the concentrated solution that flows out of the gas-liquid separator, and a float valve that adjusts the amount of the diluted solution to the high-temperature regenerator according to the liquid level of the concentrated solution in the float box; Liquid level detection for detecting the liquid level of the high-temperature regenerator while communicating the U-seal pipe for communicating the upper header and the gas phase part of the float box, the upper header and the lower header And a communication pipe provided with a vessel.

In the present invention, the following configuration is more preferable.
(1) The liquid level detector has a high level detector and a low level detector for detecting the liquid level of the diluted solution formed in the communication pipe at different heights.
(2) When the high-level detector detects a dilute solution at the start-up, the combustion device starts combustion, and controls to perform combustion at the lower limit value of the combustion amount during a preset set time, and starts combustion When the low level detector detects the liquid level later, a control device is provided for controlling to stop combustion in the combustion device.
(3) The liquid level detector is provided with a high level detector, a middle level detector, and a low level detector for detecting the liquid level of the dilute solution accumulated in the communication pipe at different heights. When the detector detects a dilute solution, combustion of the combustion device is started, and then the combustion device is burned until the liquid level in the liquid level detector is lowered and the liquid level is detected by the middle level detector. And a control device that controls to stop combustion in the combustion device when the low level detector detects the liquid level after starting combustion, while controlling to burn at the lower limit of the quantity.
(4) The outlet temperature of the cold water flowing in the evaporator is detected by a temperature sensor, and the combustion of the combustion device of the high temperature regenerator is compared with the temperature detected by the temperature sensor and the first and second preset temperatures set in advance. A control device for adjusting the amount, the control device stops the combustion device when the outlet temperature of the chilled water reaches the first set temperature at the time of partial load, and then the detected outlet temperature of the chilled water becomes the second temperature. Control is performed so that the combustion apparatus is ignited again and combustion is started when both the state where the temperature is higher than the set temperature and the state where the solution is detected by the high level detector of the liquid level detector are satisfied.
(5) The high level detector is provided at a height near the upper end of the heat transfer tube.
(6) The float valve is disposed at a position higher than the weir for preventing the solution stored in the lower part of the absorber from overflowing to the evaporator.
(7) A control device that controls the frequency of a drive power source that drives the solution circulation pump that sends a dilute solution from the absorber to the high-temperature regenerator, the intermediate-temperature regenerator, and the low-temperature regenerator, The frequency of the drive power source that drives the solution circulation pump is increased as the pressure or temperature of the high temperature regenerator increases, and the drive power source that drives the solution circulation pump is decreased as the pressure or temperature of the high temperature regenerator decreases. Control to reduce the frequency.

  According to the present invention, the performance of the gas-liquid separator is ensured from the start to the steady operation, and the air blown due to insufficient supply of the solution to the plurality of heat transfer tubes connected to the lower header and the upper header. A triple effect absorption chiller / heater can be obtained.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. The same reference numerals in the drawings of the respective embodiments indicate the same or equivalent.
Example 1
First, Example 1 of the best mode for carrying out the present invention will be described.

  FIG. 1 shows an embodiment of the present invention. First, the structure of the triple effect absorption chiller / heater of the present invention will be described. The triple effect absorption chiller / heater is composed of a high temperature regenerator 1, an evaporator 7, an absorber 8, a condenser 9, a low temperature regenerator 10, a medium temperature regenerator 11, a low temperature heat exchanger 15, and a medium temperature heat exchange surrounded by a chain line. The low-temperature regenerator 10 and the medium-temperature regenerator 11 are used as the heat exchanger elements of the heat exchanger 16 and the high-temperature heat exchanger 17, the refrigerant pump 12 for circulating the refrigerant in the evaporator 7, and the dilute dilute solution in the absorber 8. And a solution circulation pump 13 for circulating to the high temperature regenerator 1, a low temperature regenerator 10, a medium temperature regenerator 11, and a solution spray pump 14 for spraying the solution of the high temperature regenerator 1 into the absorber 8, the high temperature regenerator 1 The float box 18 is provided with a float valve 19 that adjusts the amount of solution flowing into the high-temperature regenerator 1 in accordance with the amount of solution flowing out of the solution, and a solution pipe and a refrigerant pipe connecting them.

  A high-temperature regenerator 1 surrounded by an alternate long and short dash line is a once-through type high-temperature regenerator 1 and includes a burner 6, and an upper header 2 and a lower header 3 include a plurality of heat transfer tubes 4 (hereinafter simply referred to as heat transfer tubes 4). Connected with. The upper part of the gas-liquid separator 5 and the intermediate temperature regenerator 11 are connected by a pipe 22. The pipe 22 is branched in the middle, and the branched pipe 28 is connected to the absorber 8 via a valve 29. The lower part of the gas-liquid separator 5 and the float box 18 are connected by a pipe 23.

  The dilute solution flows in the order of the lower header 3, the heat transfer tube 4, and the upper header 2, and is concentrated by heating the outside of the heat transfer tube 4 with the burner 6 to become a refrigerant vapor and a concentrated solution. The refrigerant vapor and the concentrated solution flow into the gas-liquid separator 5 in a mixed state, and are separated into the refrigerant vapor and the concentrated solution. The separated refrigerant vapor is guided to the intermediate temperature regenerator 11 through the pipe 22. The separated concentrated solution is guided to the float box 18 through the pipe 23. In addition, a communication pipe 20 that communicates the lower header 3 and the gas phase part of the float box 18 is provided. In the middle of the communication pipe 20, a liquid level detector 25 including a high level detector 26 and a low level detector 27 is provided. A pipe 24 into which a dilute solution from the absorber 8 flows is connected to the lower header 3.

  The float valve 19 in the float box 18 includes a float 19d as shown in FIG. 1, detects the liquid level position of the concentrated solution stored in the float box 18, and the liquid level of the concentrated solution in the float box 18 decreases. Then, the flow rate of the dilute solution supplied to the high temperature regenerator 1 is increased, and when the liquid level of the concentrated solution in the float box 18 rises, the flow rate of the dilute solution supplied to the high temperature regenerator 1 is adjusted to decrease. The float valve 19 in the float box 18 is provided at a position higher than a weir (not shown) provided between the absorber 8 and the evaporator 7. The weir between the absorber 8 and the evaporator 7 dilutes the solution when the operation is stopped, and the solution is caused by a pressure difference from the high pressure side of the high temperature regenerator 1, the intermediate temperature regenerator 11, and the low temperature regenerator 10 to the low pressure side of the absorber 8. Is designed so that it does not overflow into the evaporator 7 even if it flows into the evaporator 7. That is, the liquid level in the float box 18 is formed at a position lower than the float valve 19 during operation stop. Further, the high level detector 26 of the liquid level detector 25 is provided at the height of the upper end of the heat transfer tube 4 where the heat transfer tube 4 of the high temperature regenerator 1 is connected to the upper header 2, and the communication tube on the float box 18 side, for example. 20 is connected to the float box 18 at the same height as the high level detector 26.

  The triple effect absorption chiller / heater includes a control device 33. The control device 33 includes the burner 6, the high level detector 26, the low level detector 27, the valve 29, the outlet temperature sensor 31 of the cold water flowing through the tube group in the evaporator 7, the solution spray pump 14, and the frequency of the solution circulation pump 13. An inverter 32 for adjustment is connected by a signal line indicated by a broken line. In the present embodiment, water is used as the refrigerant of the triple effect absorption chiller / heater, and an aqueous lithium bromide solution is used as the absorbent. In the following description, the same parts as those in FIG.

  Next, the operation | movement in the air_conditionaing | cooling operation | movement of this triple effect absorption cold / hot water machine is demonstrated.

  The dilute solution flowing from the lower header 3 of the high-temperature regenerator 1 into the heat transfer tube 4 is heated and concentrated by the burner 6 to become a concentrated solution and refrigerant vapor, and is led from the upper header 2 to the gas-liquid separator 5 through the pipe 21. . The refrigerant vapor separated by the gas-liquid separator 5 passes through the pipe 22 and heats and concentrates the diluted solution in the intermediate temperature regenerator 11 to generate refrigerant vapor, which is condensed and liquefied and flows into the condenser 9. The refrigerant vapor generated in the intermediate temperature regenerator 11 is heated and concentrated in the dilute solution in the low temperature regenerator 10 to generate refrigerant vapor, which is condensed and liquefied and flows into the condenser 9. The refrigerant vapor generated in the low temperature regenerator 10 is cooled by the condenser 9 with the cooling water flowing in the condenser 9 to be condensed and liquefied, and is sent to the evaporator 7 together with the refrigerant from the high temperature regenerator 1 and the medium temperature regenerator 11. On the other hand, the concentrated solution separated by the gas-liquid separator 5 forms a liquid level in the float box 18, passes through the high temperature heat exchanger 17, is concentrated in the intermediate temperature regenerator 11, and passes through the intermediate temperature heat exchanger 16. Along with the solution and the concentrated solution concentrated in the low-temperature regenerator 10, the solution spray pump 14 passes through the low-temperature heat exchanger 15 to the absorber 8 and is sprayed on the tube group in the absorber 8.

  The refrigerant in the evaporator 7 is stored in the lower part of the evaporator 7 and sprayed to the tube group in the evaporator 7 by the refrigerant pump 12, and exchanges heat with the cold water flowing in the tube group. At this time, since cold water having a temperature higher than the saturation temperature of the refrigerant in the evaporator 7 is poured into the tube group in the evaporator 7, the cold water flowing in the tube group in the evaporator 7 is moved to the tube group in the evaporator 7. The refrigerant flowing down the surface is heated and the refrigerant evaporates. The cooling effect is exhibited by the latent heat of vaporization at that time. Further, in order to keep the pressure in the evaporator 7 constant, the concentrated solution concentrated by the high temperature regenerator 1, the medium temperature regenerator 11, and the low temperature regenerator 10 is sprayed on the tube group in the absorber 8, and the evaporator 7 Absorbs the refrigerant evaporated in

  At this time, the absorption heat generated when the refrigerant vapor is absorbed is removed by the cooling water flowing in the tube group in the absorber 8, and the diluted solution diluted with the refrigerant vapor from the evaporator 7 is circulated in the solution. It is supplied via a low temperature heat exchanger 15 by a pump 13. This dilute solution is branched, one is supplied to the low temperature regenerator 10, the other part is supplied via the intermediate temperature heat exchanger 16 to the intermediate temperature regenerator 11, and the rest is supplied via the high temperature heat exchanger 17. The high temperature regenerator 1 is supplied through the float valve 19 in the float box 18. Here, the dilute solution is again heated and concentrated by the burner 6 and separated from the refrigerant vapor.

  The cooling cycle is configured as described above. At this time, the pressure in the high temperature regenerator 1 is more than about three times that of the conventional double regenerator absorption double chiller / heater, and is operated exceeding the atmospheric pressure.

  Next, operations and effects around the high-temperature regenerator 1 and the float box 18 according to the present invention will be described with reference to FIG.

  First, the startup will be described. When starting up, first, the solution circulation pump 13 is operated to circulate the dilute solution. The dilute solution is adjusted in flow rate by the float valve 19 and flows into the lower header 3. Here, when the operation is stopped, the liquid level in the float box 18 is formed at a position lower than the float valve 19 and the float valve 19 is in an open state, so that the dilute solution must be supplied to the lower header 3 without fail. it can. The dilute solution supplied to the lower header 3 is distributed to the heat transfer tubes 4 and rises in the heat transfer tubes 4 and rises in the communication tubes 20 and the liquid level detector 25. At this time, since the gas phase part of the high temperature regenerator 1 and the gas phase part of the float box 18 are communicated with each other via the gas-liquid separator 5, the liquid level in the heat transfer tube 4 and the liquid level in the liquid level detector 25. The plane can be raised simultaneously. The diluted solution that has risen in the liquid level detector 25 flows into the float box 18 through the communication pipe 20, forms a liquid level in the float box 18, and is introduced into the absorber 8 by the solution spray pump 14. The dilute solution that has risen in the heat transfer tube 4 forms a liquid surface at a height in the upper header 2 that is higher than the upper end of the heat transfer tube 4. At this time, the liquid level of the diluted solution rising in the liquid level detector 25 is detected by the high level detector 26 of the liquid level detector 25. The high level detector 26 is connected to the control device 33 by a signal line, and ignites the burner 6 on the condition that it is continuously detected, for example, and starts combustion. During a preset set time, Control so that the combustion amount is burned at the lower limit. That is, the high level detector 26 is provided at the height position of the upper end of the heat transfer tube 4, and is supplied to the high temperature regenerator 1 by the solution circulation pump 13 on condition that the liquid level is continuously detected by the high level detector 26. The dilute solution rises up the heat transfer tube 4 to form the liquid level in the upper header 2 and can be introduced into the float box 18 through the communication tube 20 and the liquid level detector 25, so that the dilute solution circulates stably. Since combustion by the burner 6 is started in this state, it is possible to prevent emptying of the heat transfer tube 4 due to insufficient supply of the dilute solution.

  In addition, at the time of start-up, the solution circulation pump 13 has a double-effect absorption chiller / heater having a head twice as high as that required for a triple-effect absorption chiller / heater, and the solution circulation pump 13 suddenly turns on the power supply at the rated frequency. When supplied, a surge pressure is generated, and the impact applied to the low temperature heat exchanger 15, the medium temperature heat exchanger 16, and the high temperature heat exchanger 17 on the discharge side of the solution circulation pump 13 is increased, resulting in a problem in durability. Therefore, the frequency of the inverter 32 that supplies power is controlled by the control device 33 based on the value detected by the pressure sensor 30 provided in the gas-liquid separator 5 of the high-temperature regenerator 1, and the frequency is kept low during startup when the pressure is low. Control is performed so as to alleviate the impact on the low temperature heat exchanger 15, intermediate temperature heat exchanger 16, and high temperature heat exchanger 17 on the discharge side of the solution circulation pump 13 by providing a startup time up to the set frequency.

  Furthermore, at the time of start-up, since the temperature of the dilute solution supplied to the high temperature regenerator 1 is about the outside air temperature and the pressure in the high temperature regenerator 1 is about 1/100 atm. The density of the refrigerant vapor generated in the heat transfer tube 4 is as small as about 1/200 of the rated operation, and the speed of the vapor and liquid refrigerant vapor and concentrated solution flowing into the gas-liquid separator 5 is greatly increased. However, if a liquid surface of a concentrated solution is formed in the gas-liquid separator 5 as in a high-temperature regenerator (not shown) described in Japanese Patent Application Laid-Open No. 2003-227661, the liquid of the concentrated solution is formed. There is a concern that the surface is agitated and the concentrated solution is accompanied by the refrigerant vapor and mixed into the refrigerant side, and the evaporation temperature of the refrigerant in the evaporator 7 increases and the performance deteriorates. However, as shown in FIG. 1, in the form of the first embodiment, since the concentrated solution is not stored in the gas-liquid separator 5, the entire gas-liquid separator 5 can be used for gas-liquid separation. 5 can be sufficiently exerted, and it is possible to minimize the concentration of the concentrated solution accompanying the refrigerant vapor on the refrigerant side. Further, by burning the burner 6 started after the liquid level is continuously detected by the high level detector 26 of the liquid level detector 25, the combustion amount is burned at the lower limit value during a preset set time. The amount of refrigerant vapor generated when the dilute solution is heated can be suppressed to a low level. For example, if the preset time is 10 minutes, the liquid level formed in the upper header 2 of the high-temperature regenerator 1 during this time Gradually decreases to form a liquid surface in the heat transfer tube 4. Thereby, since the area of the liquid level formed in the high temperature regenerator 1 and stirred by the refrigerant vapor and the concentrated solution can be reduced, the amount of the concentrated solution accompanying the refrigerant vapor by the stirring can be reduced. Thereafter, even if the combustion amount of the burner 6 is increased in accordance with the cooling load, the area of the liquid surface stirred by the refrigerant vapor and concentrated solution formed in the high-temperature regenerator 1 can be limited to the heat transfer tube 4 only. Therefore, the amount of the concentrated solution accompanying the refrigerant vapor by stirring can be minimized.

  Therefore, according to the first embodiment, at the time of start-up, it is possible to simultaneously prevent the heat transfer tube 4 of the high-temperature regenerator 1 from being blown and prevent the concentrated solution from being mixed into the refrigerant side, thereby improving safety. .

  Next, the process from start to stability will be described. After the start-up, combustion by the burner 6 is started and the dilute solution boils in the heat transfer tube 4 and a lot of voids are generated, so that the liquid level in the liquid level detector 25 gradually decreases, and a preset set time is set. Thereafter, the liquid level in the liquid level detector 25 is stabilized when the combustion amount of the burner 6 controlled by the control device 33 and the flow rate of the diluted solution whose flow rate is adjusted by the float valve 19 are balanced. The combustion amount of the burner 6 is higher than the first set value by comparing the temperature detected by the outlet temperature sensor 31 provided at the cold water outlet with the control device 33 and the first set value set in advance. If the amount of combustion is large, and the temperature difference is higher than the first set value and the temperature difference is small, the controller 33 controls the amount of combustion to be small. Moreover, since the pressure in the high-temperature regenerator 1 gradually increases after combustion by the burner 6, if the frequency of the inverter 32 of the solution circulation pump 13 is kept low at the time of startup, the circulation amount of the diluted solution decreases. End up. Therefore, when the pressure detected by the pressure sensor 30 is increased by the control device 33, control is performed so that the frequency of the inverter 32 of the solution circulation pump 13 is increased, and conversely, the pressure detected by the pressure sensor 30 is decreased. In this case, control is performed so that the frequency of the inverter 32 of the solution circulation pump 13 decreases.

  In the state where the triple effect absorption chiller / heater of the first embodiment shown in FIG. 1 is operated from the start to the stop, for example, a failure of the solution circulation pump 13, a pressure sensor 30 for controlling the solution circulation pump 13, etc. If the pump control function of the inverter 32 or the control device 33 fails, or the solution piping is clogged, the supply of the dilute solution to the high temperature regenerator 1 is insufficient. There is a possibility that the high-temperature regenerator 1 may be damaged or ruptured. However, according to the present embodiment, when the shortage of the dilute solution to the high temperature regenerator 1 occurs due to the above cause, the liquid level in the heat transfer tube 4 of the high temperature regenerator 1 is the liquid level in the liquid level detector 25. Even if the liquid level decreases, a low level detector 27 of the liquid level detector 25 is provided at a position higher than the so-called empty liquid level by a margin, and the low level detector 27 continuously. When the liquid level is detected, the control device 33 controls the fuel to be burned to the burner 6 to stop combustion, thereby preventing the heat transfer tube 4 from being blown. At this time, the height at which the low level detector 27 of the liquid level detector 25 is installed depends on the wall temperature of the heat transfer tube 4 when the combustion amount of the burner 6 or the supply amount of the dilute solution to the high temperature regenerator 1 changes. Set the height so that it can be confirmed that the temperature is within the safe temperature range determined from the actual results and experience.

  Further, for example, when the liquid level is detected by the low level detector 27 of the liquid level detector 25, the control device 33 stops the combustion of the burner 6 and simultaneously stops the solution circulation pump 13 and the solution spray pump, and the valve of the pipe 28. 29 is opened. That is, when the supply of heat to the high temperature regenerator 1 is insufficient and the low level detector 27 stops the combustion of the burner 6 to prevent emptying, the solution circulation pump 13 and the solution spray pump 14 are operated. Since the circulation failure of the dilute solution has occurred on the solution circulation pump 13 side, the ratio of the concentrated solution flowing into the absorber 8 becomes larger than the dilute solution flowing out from the absorber 8, and the solution accumulated in the lower portion of the absorber 8 increases. As a result, the allowable amount is exceeded and the evaporator 7 overflows. Furthermore, if the solution circulation pump 13 and the solution spray pump 14 are operated thereafter, the concentrated solution on the suction side of the solution spray pump 14 becomes insufficient, so that the solution spray pump 14 may be damaged due to cavitation or the like. There is. Moreover, the overflow of the solution from the absorber 8 to the evaporator 7 can be prevented by reducing the pressure difference between the high temperature regenerator 1 and the absorber 8 by opening the valve 29 of the pipe 28. As a result, problems such as cycle performance degradation and inability to operate can be prevented.

  Next, the operation at the partial load when the combustion amount of the burner 6 is lower than can be handled by the lower limit value will be described. At the time of partial load, the temperature difference between the temperature detected by the cold water outlet temperature sensor 31 and the first set value set in advance is small, and the combustion amount of the burner 6 is operated by the control device 33 at the lower limit value. In this case, when the temperature detected by the cold water outlet temperature sensor 31 reaches the first set value, the controller 33 performs control so that the burner 6 of the high-temperature regenerator 1 is repeatedly burned and stopped. When operating with a partial load in this way, when combustion of the burner 6 is stopped by the control device 33, the solution circulation pump 13 and the solution spray pump 14 are operated, so that the inside of the heat transfer tube 4 of the high-temperature regenerator 1. The liquid level rises to the high level detector 26 provided at the height of the upper end of the heat transfer tube 4. At this time, when the burner 6 is stopped at the time of partial load in the control device 33, the temperature detected by the outlet temperature sensor 31 of the cold water in the control device 33 is higher than the first set value and equal to or higher than the second set value. Control is performed to start burning of the burner 6 when both the state and the state in which the high level detector 26 of the liquid level detector 25 continuously detects the diluted solution are satisfied. Thereby, even when the partial load is applied, when the burner 6 of the high-temperature regenerator 1 starts to burn again, the liquid level of the dilute solution in the heat transfer tube 4 can be made higher than the upper end of the heat transfer tube 4. It is possible to prevent emptying due to insufficient supply of the solution, and to smoothly burn and stop the burner 6.

  By configuring and controlling as described above, the operation of the high-temperature regenerator 1 is improved while preventing the heat transfer tube 4 of the high-temperature regenerator 1 from being blown in the start-up, stable operation, and partial load operation. Since it becomes possible to operate without accumulating the concentrated solution in the gas-liquid separator 5, it is possible to minimize the concentration of the concentrated solution on the refrigerant side.

According to the present embodiment, the following effects can be obtained.
(1) Since a float box that forms a liquid surface is provided at the gas-liquid separator outlet and the solution is not stored in the gas-liquid separator, the entire gas-liquid separator is used for separation of the refrigerant vapor and the solution. be able to. That is, the refrigerant vapor and the solution can be efficiently separated, and the solution can be prevented from being mixed into the refrigerant. Furthermore, since a volume for storing the solution in the gas-liquid separator is not required, the gas-liquid separator can be miniaturized.
(2) By providing a liquid level detector in the communication pipe that communicates the gas phase part of the float box at the outlet of the gas-liquid separator and the lower header of the high-temperature regenerator, from start-up to steady operation, and even partial load Even during repeated operation of combustion / stop of the combustion device at the time, it is possible to prevent emptying of the heat transfer tube of the high-temperature regenerator caused by insufficient supply of solution, ensuring the safety of the triple effect absorption chiller / heater efficiently You can drive.
(Example 2)
Next, Example 2 of the best mode for carrying out the present invention will be described with reference to FIG. The embodiment 2 shown in FIG. 2 is different from the embodiment 1 shown in FIG. 1 in that a middle detector 36 is provided between the high level detector 26 and the low level detector 27 of the liquid level detector 25. It is configured to be connected to the control device 33 by a signal line. That is, the middle detector 36 is provided at a position lower than the upper end of the heat transfer tube 4. Here, at the time of start-up, in the form of the first embodiment of FIG. 1, it is assumed that the combustion amount is burned at the lower limit value for a preset time after the start of the combustion of the burner 6, but in the second embodiment of FIG. In the embodiment, the combustion amount is controlled to be the lower limit value until the liquid level is detected by the middle level detector 36 provided in the liquid level detector 25 after the start of combustion in the burner 6. As a result, the liquid level in the high-temperature regenerator 1 that decreases due to the generation of voids after the start of combustion by the burner 6 can be more reliably brought into the heat transfer tube 4 from the upper header 2, and the dilute solution is heated and generated. The area of the liquid surface stirred with the refrigerant vapor and the concentrated solution is reduced, and the amount of the concentrated solution accompanying the refrigerant vapor can be minimized.
Example 3
Next, a third embodiment of the best mode for carrying out the present invention will be described with reference to FIG. The basic components of the embodiment 3 in FIG. 3 are the same as those in the embodiment 1 in FIG.

  1 is different from the first embodiment in FIG. 1 in that a liquid level detector including a high level detector 26 and a low level detector 27 in which the upper header 2 and the gas phase portion of the float box 18 are connected by a U seal pipe 35. 25 is provided in the middle of the communication pipe 34 that communicates the upper header 2 and the lower header 3.

  At the time of start-up, the dilute solution supplied to the lower header 3 by the solution circulation pump 13 is distributed to each heat transfer tube 4 and rises in the heat transfer tube 4 and rises in the communication tube 34 and the liquid level detector 25. . At this time, since the heat transfer tube 4 and the communication tube 34 communicate with each other via the upper header 2, the liquid level in the heat transfer tube 4 and the liquid level in the liquid level detector 25 can be raised simultaneously. The dilute solution that has risen in the heat transfer tube 4 and the liquid level detector 25 rises to the upper header 2, flows into the float box 18 through the U-seal pipe 35, forms a liquid surface in the float box 18, and forms a solution. It is introduced into the absorber 8 by the spray pump 14. The U seal pipe 35 connected to the float box 18 side is connected to a position lower than the upper header 2. Further, the U seal pipe 35 is designed to have a U seal height so that the refrigerant vapor and the concentrated solution do not blow from the upper header 2 into the float box 18 when the burner 6 is burned. At this time, the liquid level of the diluted solution rising in the liquid level detector 25 is detected by the high level detector 26 of the liquid level detector 25. The high level detector 26 is connected to the control device 33 by a signal line, and for example, by confirming that the detection is continuously performed, the burner 6 is ignited to start combustion, and the combustion amount is set during a preset time. Is controlled to burn at the lower limit. That is, the high level detector 26 is provided at the height position of the upper end of the heat transfer tube 4, and the liquid level is continuously detected by the high level detector 26, whereby the dilute solution supplied to the high temperature regenerator 1 by the solution circulation pump 13. Can rise up the heat transfer tube 4 to form the liquid level at the upper header 2 and can be introduced into the float box 18 through the U-seal pipe 35, and the burner 6 can be used to stably circulate the dilute solution. Combustion can begin. Thereby, the operation | movement and effect similar to the form of Example 1 of FIG. 1 can be acquired.

Furthermore, since the operation similar to that of the first embodiment shown in FIG. 1 can be performed in the stable and partial load operation as in the start-up, the emptying of the heat transfer tube 4 of the high-temperature regenerator 1 can be performed. It is possible to prevent and improve safety, and to operate without accumulating the concentrated solution in the gas-liquid separator 5 of the high-temperature regenerator 1, thereby minimizing the concentration of the concentrated solution on the refrigerant side. it can.
Example 4
Next, Example 4 of the best mode for carrying out the present invention will be described with reference to FIG.

  The embodiment 4 shown in FIG. 4 is different from the embodiment 3 shown in FIG. 3 in that a middle level detector 36 is provided between the high level detector 26 and the low level detector 27 of the liquid level detector 25. It is configured to be connected to the control device 33 by a signal line. That is, the middle detector 36 is provided at a position lower than the upper end of the heat transfer tube 4. Here, at the time of start-up, in the form of Example 4 in FIG. 4, the combustion amount is performed at the lower limit until the liquid level is detected by the middle level detector 36 provided in the liquid level detector 25 after the start of combustion in the burner 6. To control. As a result, the liquid level in the high-temperature regenerator 1 that decreases due to the generation of voids after the start of combustion by the burner 6 can be more reliably brought into the heat transfer tube 4 from the upper header 2, and the dilute solution is heated and generated. The area of the liquid surface stirred with the refrigerant vapor and the concentrated solution is reduced, and the amount of the concentrated solution accompanying the refrigerant vapor can be minimized.

It is a figure which shows the cycle flow of the triple effect absorption cold / hot water machine which concerns on embodiment of this invention. It is a figure which shows the cycle flow of the triple effect absorption cold / hot water machine which concerns on other embodiment of this invention. It is a figure which shows the cycle flow of the triple effect absorption cold / hot water machine which concerns on other embodiment of this invention. It is a figure which shows the cycle flow of the triple effect absorption cold / hot water machine which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High temperature regenerator 2 Upper header 3 Lower header 4 Heat transfer tube 5 Gas-liquid separator 6 Burner 7 Evaporator 8 Absorber 9 Condenser 10 Low temperature regenerator 11 Medium temperature regenerator 12 Refrigerant pump 13 Solution circulation pump 14 Solution spray pump 15 Low temperature heat exchanger 16 Medium temperature heat exchanger 17 High temperature heat exchanger 18 Float box 19 Float valve 20 Communication pipe 1
25 Liquid level detector 26 High level detector 27 Low level detector 29 Valve 30 Pressure sensor 31 Cold water outlet temperature sensor 32 Inverter 33 Controller 34 Communication pipe 2
35 U seal piping

Claims (9)

High temperature regenerator, medium temperature regenerator, low temperature regenerator, condenser, evaporator, absorber, high temperature heat exchanger, medium temperature heat exchanger, low temperature heat exchanger, solution circulation pump, solution spray pump, refrigerant pump with solution piping and Connect with refrigerant piping to form a solution / refrigerant circulation circuit,
The high-temperature regenerator includes a lower header into which a dilute solution flows, an upper header from which a mixture of concentrated solution and refrigerant vapor flows out, and a plurality of heat transfer tubes connecting the lower header and the upper header. A once-through high temperature regeneration system comprising a combustion device for circulating combustion gas outside a plurality of heat transfer tubes, and a gas-liquid separator for separating a concentrated solution and refrigerant vapor flowing out of the upper header Composed of
In the triple-effect absorption chiller / heater, the gas-liquid separator is a refrigerant vapor that flows out from the upper part and a concentrated solution flows out from the lower part.
A float box for forming a liquid level of the concentrated solution flowing out from the gas-liquid separator; a float valve for adjusting a dilute solution amount to the high temperature regenerator according to a liquid level of the concentrated solution in the float box; A triple effect absorption cold temperature characterized by comprising a communicating pipe that communicates the header and the gas phase part of the float box and that is provided with a liquid level detector for detecting the liquid level of the high temperature regenerator. Water machine. High temperature regenerator, medium temperature regenerator, low temperature regenerator, condenser, evaporator, absorber, high temperature heat exchanger, medium temperature heat exchanger, low temperature heat exchanger, solution circulation pump, solution spray pump, refrigerant pump with solution piping and Connect with refrigerant piping to form a solution / refrigerant circulation circuit,
The high-temperature regenerator includes a lower header into which a dilute solution flows, an upper header from which a mixture of concentrated solution and refrigerant vapor flows out, and a plurality of heat transfer tubes connecting the lower header and the upper header. A once-through high temperature regeneration system comprising a combustion device for circulating a combustion gas outside a plurality of heat transfer tubes, and a gas-liquid separator for separating a concentrated solution and refrigerant vapor flowing out of the upper header Composed of
In the triple-effect absorption chiller / heater, the gas-liquid separator is a refrigerant vapor that flows out from the upper part and a concentrated solution flows out from the lower part.
A float box for forming a liquid level of the concentrated solution flowing out from the gas-liquid separator, a float valve for adjusting a dilute solution amount to the high temperature regenerator according to a liquid level of the concentrated solution in the float box, and the upper part A liquid level detector for communicating the U-seal pipe for communicating the header and the gas phase part of the float box, the upper header and the lower header, and detecting the liquid level of the high-temperature regenerator; A triple-effect absorption chiller / heater characterized by comprising a communication pipe provided. In claim 1 or 2,
The triple level absorption chiller / heater characterized in that the liquid level detector has a high level detector and a low level detector for detecting the liquid level of a dilute solution formed in the communication pipe at different heights. . In claim 3,
When the high level detector detects a dilute solution at the time of start-up, the combustion device starts combustion, and controls to perform combustion at the lower limit value of the combustion amount during a preset set time, and after the start of combustion, the low level detector A triple effect absorption chiller / heater comprising a control device that controls to stop combustion in the combustion device when the detector detects a liquid level. In claim 1 or 2,
The liquid level detector is provided with a high level detector, a middle level detector, and a low level detector for detecting the liquid level of the dilute solution accumulated in the communication pipe at different heights,
When the high level detector detects a dilute solution at the time of start-up, combustion of the combustion device starts, and then the liquid level in the liquid level detector is lowered until the liquid level is detected by the middle level detector. A control device is provided for controlling the combustion device to burn at the lower limit value of the combustion amount, and for controlling the combustion device to stop combustion when the low level detector detects the liquid level after the start of combustion. A triple effect absorption chiller / heater. In any one of Claims 3-5,
The outlet temperature of the cold water flowing in the evaporator is detected by a temperature sensor, and the combustion amount of the combustion device of the high-temperature regenerator is adjusted by comparing the temperature detected by the temperature sensor with the first and second preset temperatures set in advance. Control device
The control device stops the combustion device when the outlet temperature of the cold water reaches the first set temperature at the time of partial load, and then the state where the outlet temperature of the detected cold water becomes higher than the second set temperature and the liquid level A triple effect absorption chiller / heater characterized by controlling the combustion device to ignite again and start combustion when both the state where the solution is detected by the high level detector of the detector are satisfied. In any one of Claims 3-6,
The high effect detector is provided at a height near the upper end of the heat transfer tube. In any one of Claims 1-7,
The triple-effect absorption chiller / heater is characterized in that the float valve is disposed at a position higher than a weir for preventing an overflow of the solution stored in the lower part of the absorber to the evaporator. In any one of Claims 1-8,
A control device for controlling the frequency of a drive power source that drives the solution circulation pump that sends a dilute solution from the absorber to the high temperature regenerator, the intermediate temperature regenerator, and the low temperature regenerator;
The control device increases the frequency of the drive power source that drives the solution circulation pump as the pressure or temperature of the high temperature regenerator increases, and drives the solution circulation pump as the pressure or temperature of the high temperature regenerator decreases. A triple-effect absorption chiller / heater that is controlled to reduce the frequency of the drive power supply.

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