Combustion device, absorption water cooling / heating machine, and combustion amount control method

Abstract

To provide a combustion device, an absorption water cooling / heating machine, and a combustion amount control method, which simultaneously supply fuel of different types to a burner and ensure proper combustion thereof.SOLUTION: A combustion device 70 comprises: a storage unit 63 that stores a first relationship defining a flow rate-related value of air A corresponding to a flow rate-related value of first fuel F1 supplied to a burner 71, and a similar second relationship pertaining to a second fuel F2; and a control unit 61 that controls an air flow rate adjustment mechanism 77 so as to supply, to the burner 71, a supply air flow rate obtained on the basis of a value obtained by summing the flow rate-related values of the air A obtained from the first relationship and the second relationship, respectively. An absorption water cooling / heating machine comprises: the combustion device 70; a regenerator including at least the burner 71 of the combustion device 70; a condenser; and an evaporator. The control unit 61 operates the combustion device 70 with a smaller combustion amount between a combustion amount in the burner 71 for bringing a temperature of a cooling target medium to a target temperature and an upper limit combustion amount for maintaining proper operation of the absorption water cooling / heating machine.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a combustion device, an absorption hot / chilled water machine, and a method for controlling a combustion amount, and more particularly to a combustion device, an absorption hot / chilled water machine, and a method for controlling a combustion amount that simultaneously supplies different types of fuels to a burner. [Background technology]

[0002] The absorption chiller-heater is a device that cools a medium to be cooled (chilled water) by removing the latent heat of evaporation required for evaporating a refrigerant liquid in an evaporator to become a refrigerant vapor from the medium to be cooled, and the refrigerant vapor generated in the evaporator is absorbed by an absorbing liquid in an absorber. The absorbing liquid in the absorber, which has absorbed the refrigerant vapor and has a reduced concentration, is sent to a regenerator and heated, where its concentration increases. The absorbing liquid, whose concentration has increased in the regenerator, is returned to the absorber, and becomes capable of absorbing the refrigerant vapor generated in the evaporator again. One method of heating the absorbing liquid in the regenerator is to provide a combustion device that burns fuel in the regenerator. An example of such a combustion device is one that maintains an appropriate air-fuel ratio by individually controlling the supply flow rates of fuel and air to a burner based on the relationship between the flow rate of fuel, the flow rate of air, and the amount of oxygen in the air that is stored in advance and is suitable for combustion in the burner (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-223428 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the past, fossil fuels such as commercial gas and oil were generally used as fuels to be burned in burners. However, as the effects of global warming become more pronounced, there is a growing trend to reduce the use of fossil fuels, and if even a portion of fossil fuels could be replaced with carbon-free or carbon-neutral fuels, this would contribute to reducing the emission of carbon dioxide, which causes global warming. However, since the appropriate air flow rate differs depending on the type of fuel, it is difficult to adjust the air flow rate to be supplied when burning different types of fuel.

[0005] In view of the above-mentioned problems, the present disclosure relates to providing a combustion device, an absorption chiller / heater, and a combustion amount control method that are capable of appropriately combusting fuels when different types of fuel are supplied to a burner at the same time. [Means for solving the problem]

[0006] A combustion device according to a first aspect of the present disclosure includes a burner, a first supply mechanism for supplying a first fuel to the burner, the first supply mechanism having a first adjustment mechanism for adjusting a flow rate of the first fuel supplied to the burner, a second supply mechanism for supplying a second fuel of a different type from the first fuel to the burner, the second supply mechanism having a second adjustment mechanism operating independently of the first adjustment mechanism for adjusting a flow rate of the second fuel supplied to the burner, and an air supply mechanism for supplying air to the burner, the second supply mechanism operating independently of the first adjustment mechanism and the second adjustment mechanism for adjusting a flow rate of the second fuel supplied to the burner. the air supply mechanism having an air flow rate adjustment mechanism for adjusting the flow rate of the first fuel; a memory unit storing a first relationship defining a value related to the air flow rate corresponding to a value related to the flow rate of the first fuel supplied to the burner, and a second relationship defining a value related to the air flow rate corresponding to a value related to the flow rate of the second fuel supplied to the burner; and a control unit controlling the air flow rate adjustment mechanism to supply to the burner a supply air flow rate, which is an air flow rate based on a total air flow rate related value obtained by summing up the value related to the air flow rate obtained from the first relationship and the value related to the air flow rate obtained from the second relationship.

[0007] With this configuration, when different types of fuel are supplied to the burner at the same time, an appropriate flow rate of air can be supplied to the burner, allowing the fuel to be burned appropriately.

[0008] A combustion device according to a second aspect of the present disclosure is the combustion device according to the first aspect of the present disclosure, wherein the first relationship is defined by the relationship between a control amount of the first adjustment mechanism and a control amount of the air flow adjustment mechanism, the second relationship is defined by the relationship between the control amount of the second adjustment mechanism and a control amount of the air flow adjustment mechanism, the total air flow related value is a value obtained by summing the control amount of the air flow adjustment mechanism obtained from the first relationship and the control amount of the air flow adjustment mechanism obtained from the second relationship, and the supply air flow is an air flow rate corresponding to the control amount of the air flow adjustment mechanism obtained by adding at least one of a coefficient determined in relation to a control characteristic of the first adjustment mechanism and a coefficient determined in relation to a control characteristic of the second adjustment mechanism to at least one of the control amount of the air flow adjustment mechanism determined from the first relationship and the control amount of the air flow adjustment mechanism determined from the second relationship in the total air flow related value.

[0009] With this configuration, the supply air flow rate is determined from the control amount of the first adjustment mechanism, the control amount of the second adjustment mechanism, and the control amount of the air flow adjustment mechanism, so that air at an appropriate flow rate can be supplied to the burner in a responsive manner.

[0010] Further, a combustion device according to a third aspect of the present disclosure is the combustion device according to the first or second aspect of the present disclosure, wherein the control unit controls at least one of the first adjustment mechanism and the second adjustment mechanism so that the sum of the amount of heat generated when the first fuel is burned and the amount of heat generated when the second fuel is burned is equal to or less than a maximum amount of heat allowed by the combustion device.

[0011] With this arrangement, overloading of the combustion device can be prevented.

[0012] A combustion device according to a fourth aspect of the present disclosure is a combustion device according to any one of the first to third aspects of the present disclosure, further comprising an oxygen concentration-related physical quantity detector that detects a physical quantity related to the oxygen concentration contained in exhaust gas generated by burning at least one of the first fuel and the second fuel, and the control unit controls the air flow rate regulating mechanism so that the physical quantity detected by the oxygen concentration-related physical quantity detector becomes a predetermined value.

[0013] With this configuration, the oxygen concentration in the exhaust gas can be adjusted to a desired concentration, and the occurrence of incomplete combustion or misfire can be suppressed.

[0014] A combustion device according to a fifth aspect of the present disclosure is a combustion device according to any one of the first to fourth aspects of the present disclosure, wherein the memory unit stores a plurality of patterns regarding the allocation of the first fuel and the second fuel in relation to the amount of heat required by the combustion device, and the control unit controls the first adjustment mechanism and the second adjustment mechanism according to one pattern selected from the plurality of stored patterns.

[0015] With this configuration, an appropriate distribution pattern can be set according to the supply conditions of the first fuel and the second fuel.

[0016] An absorption chiller-heater according to a sixth aspect of the present disclosure is an absorption chiller-heater having a combustion device according to any one of the first to fifth aspects of the present disclosure, comprising: a regenerator that evaporates a refrigerant contained in an absorption liquid by heat generated by the burner to increase a concentration of the absorption liquid; a condenser that cools the refrigerant vapor introduced from the regenerator to form a refrigerant liquid; and an evaporator that cools a medium to be cooled by using the refrigerant liquid introduced from the condenser to remove latent heat of evaporation from the medium to be cooled, wherein the control unit compares an amount of combustion in the burner for bringing the medium to be cooled to a target temperature with an upper limit amount of combustion in the burner for maintaining proper operation of the absorption chiller-heater, and operates the combustion device with the smaller amount of combustion.

[0017] With this configuration, an absorption chiller-heater can be provided that can maintain proper operation while utilizing a plurality of types of fuel.

[0018] An absorption chiller-heater according to a seventh aspect of the present disclosure is an absorption chiller-heater having a combustion device according to any one of the first to fifth aspects of the present disclosure, the absorption chiller-heater having at least the burner provided in the combustion device, and comprising: a regenerator that evaporates a refrigerant contained in an absorption liquid by heat generated by the burner to increase a concentration of the absorption liquid; a condensation section that condenses the refrigerant vapor introduced from the regenerator to form a refrigerant liquid; and an absorption section in which the absorption liquid absorbs the refrigerant vapor, wherein the absorption liquid is configured to heat a medium to be heated by at least one of condensation heat generated when the refrigerant vapor is condensed in the condensation section and absorption heat generated when the refrigerant vapor is absorbed by the absorption liquid in the absorption section, and the control section compares an amount of combustion in the burner for bringing the medium to be heated to a target temperature with an upper limit amount of combustion in the burner for maintaining proper operation of the absorption chiller-heater, and operates the combustion device with the smaller amount of combustion.

[0019] With this configuration, an absorption chiller-heater can be provided that can maintain proper operation while utilizing a plurality of types of fuel.

[0020] Furthermore, a combustion amount control method according to an eighth aspect of the present disclosure includes the steps of: determining a flow rate of a first fuel to be supplied to a burner; determining a flow rate of a second fuel, different in type from the first fuel, to be supplied to the burner; calculating an air flow rate corresponding to the flow rate of the first fuel to be supplied to the burner from a predetermined first relationship; calculating an air flow rate corresponding to the flow rate of the second fuel to be supplied to the burner from a predetermined second relationship; determining an air flow rate to be supplied to the burner based on a total air flow rate obtained by summing the air flow rate determined from the first relationship and the air flow rate determined from the second relationship; and supplying the first fuel, the second fuel, and the air at the determined flow rates to the burner.

[0021] With this configuration, when different types of fuel are supplied to the burner at the same time, an appropriate flow rate of air can be supplied to the burner, allowing the fuel to be burned appropriately. Effect of the Invention

[0022] According to the present disclosure, when different types of fuels are supplied to the burner simultaneously, an appropriate flow rate of air can be supplied to the burner, allowing the fuels to be combusted appropriately. [Brief description of the drawings]

[0023] [Figure 1] 1 is a schematic system diagram of a combustion device according to a first embodiment. [Diagram 2] 4 is a graph showing an example of the relationship between the flow rate of fuel supplied to a burner provided in the combustion device according to the first embodiment and the flow rate of air required for performing appropriate combustion. [Diagram 3] 4A is a graph showing an example of the relationship between the load factor of the combustion device according to the first embodiment and the ratio of the consumption amounts of the first fuel and the second fuel, and FIG. 4B is a graph showing another example of the same relationship. [Figure 4] 6 is a flowchart showing a method for controlling a combustion amount according to a second embodiment. [Diagram 5] 6 is a graph illustrating an example of the relationship between the opening degree of a first fuel damper and a coefficient. [Figure 6] FIG. 11 is a schematic system diagram of an absorption chiller-heater according to a third embodiment. [Figure 7] (A) is a schematic diagram showing a first hot water generation form in an absorption chiller-heater of the third embodiment, (B) is a schematic diagram showing a second hot water generation form in the same embodiment, and (C) is a schematic diagram showing a third hot water generation form in the same embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, an embodiment will be described with reference to the drawings. In the drawings, the same or similar reference numerals are used to designate the same or corresponding parts, and duplicated explanations will be omitted.

[0025] First, a combustion device 70 according to a first embodiment of the present disclosure will be described with reference to Fig. 1. Fig. 1 is a schematic system diagram of the combustion device 70. The combustion device 70 is a device that can simultaneously and appropriately burn a first fuel (hereinafter referred to as "first fuel F1") and a second fuel (hereinafter referred to as "second fuel F2") that are different types. In this embodiment, the first fuel F1 will be described as a commercial gas such as city gas or propane gas, and the second fuel F2 as hydrogen.

[0026] The intention of the combustion device 70 according to this embodiment is to replace at least a part of the first fuel F1, which is commercial gas, with the second fuel F2, which is hydrogen, a type of carbon-free fuel, to reduce the amount of carbon dioxide emissions associated with the reduction in the first fuel F1. In general, when fuel is burned with a burner, air is supplied to the burner at a flow rate such that the oxygen concentration in the exhaust gas after the fuel is burned falls within a predetermined range (for example, 1% to 10%). If the fuel is one type whose calorific value per unit time does not change, it is easy to determine an appropriate air flow rate, but if two different types of fuel are supplied to the burner, it is difficult to adjust the air flow rate so that the oxygen concentration in the exhaust gas falls within a predetermined range. The combustion device 70 according to this embodiment is intended to solve such a problem.

[0027] The combustion device 70 includes a burner 71, a mechanism for supplying a first fuel F1 to the burner 71, a mechanism for supplying a second fuel F2 to the burner 71, a mechanism for supplying air A to the burner 71, and a mechanism for discharging exhaust gas E after the first fuel F1 and the second fuel F2 are combusted by the burner 71. The combustion device 70 also includes a control unit 61 that controls the operation of each device that constitutes the combustion device 70, and a memory unit 63 in which data used for the control of the control unit 61 is stored.

[0028] The burner 71 is capable of generating combustion heat by introducing a first fuel F1, a second fuel F2, and air A and combusting the first fuel F1 and the second fuel F2. The burner 71 is configured to introduce the first fuel F1, the second fuel F2, and the air A separately. In other words, the first fuel F1, the second fuel F2, and the air A are not mixed before reaching the burner 71.

[0029] The mechanism (corresponding to the first supply mechanism) for supplying the first fuel F1 to the burner 71 has a first fuel supply pipe 72 and a first fuel damper 74. The first fuel supply pipe 72 is a pipe that serves as a flow path for guiding the first fuel F1 supplied from a supply source (not shown) such as a gas supply company to the burner 71. The first fuel supply pipe 72 is provided with an opening / closing valve 73 capable of blocking the flow of the first fuel F1. The first fuel damper 74 is also provided in the first fuel supply pipe 72. The first fuel damper 74 is capable of adjusting the flow rate of the first fuel F1 supplied to the burner 71, and corresponds to a first adjustment mechanism. The first fuel damper 74 is typically configured to adjust the volumetric flow rate of the first fuel F1. From the viewpoint of flow rate control of the first fuel F1, it is preferable to use an opposed-wing type volume damper as the first fuel damper 74.

[0030] The mechanism for supplying the second fuel F2 to the burner 71 (corresponding to the second supply mechanism) has a second fuel supply pipe 82 and a second fuel damper 84. The second fuel supply pipe 82 is a pipe that serves as a flow path for guiding the second fuel F2 supplied from a hydrogen supply source (not shown) such as a process in which hydrogen is produced, to the burner 71. Note that the hydrogen (second fuel F2) from the supply source such as the process may be produced as a main product at the supply source, or may be produced as a by-product. The second fuel supply pipe 82 is provided with an opening / closing valve 83 that can block the flow of the second fuel F2. The second fuel damper 84 is also provided in the second fuel supply pipe 82. The second fuel damper 84 can adjust the flow rate of the second fuel F2 supplied to the burner 71, and corresponds to a second adjustment mechanism. The second fuel damper 84 is adapted to operate independently of the first fuel damper 74 (without regard to the operation of the first fuel damper 74). The second fuel damper 84 is typically configured to adjust the volume flow rate of the second fuel F2. From the viewpoint of flow rate control of the second fuel F2, it is preferable to use an opposed-wing type volume damper as the second fuel damper 84.

[0031] The mechanism for supplying air A to the burner 71 (corresponding to an air supply mechanism) has an air supply pipe 75, an air fan 76, and an air damper 77. The air supply pipe 75 is a pipe that serves as a flow path for guiding the air A to the burner 71. The air fan 76 is disposed in the air supply pipe 75 and pressurizes and sends the air A toward the burner 71. The air damper 77 is disposed in the air supply pipe 75. The air damper 77 can adjust the flow rate of the air A supplied to the burner 71 and corresponds to an air flow rate adjustment mechanism. The air damper 77 is configured to adjust the volumetric flow rate of the air A. The air damper 77 can be of the same type as the first fuel damper 74 and / or the second fuel damper 84 (for example, an opposed-wing type volume damper). The air damper 77 is configured to be able to operate independently of the first fuel damper 74 and the second fuel damper 84. In other words, first fuel damper 74 and / or second fuel damper 84 and air damper 77 are not connected by a commonly used link mechanism, so that the opening adjustments are not linked and each can be adjusted to any desired opening.

[0032] The mechanism for discharging the exhaust gas E from the burner 71 has an exhaust gas pipe 78 and an oxygen concentration meter 79. The exhaust gas pipe 78 is a pipe that serves as a flow path for guiding the exhaust gas E generated by burning the first fuel F1 and the second fuel F2 by the burner 71 to the outside of the system (outside the combustion device 70). The oxygen concentration meter 79 is typically provided in the exhaust gas pipe 78, and is an instrument that measures the oxygen concentration in the exhaust gas E. The oxygen concentration in the exhaust gas E is a physical quantity related to the oxygen concentration contained in the exhaust gas E, and the oxygen concentration meter 79 corresponds to an oxygen concentration-related physical quantity detector. Note that a nitrogen oxide meter may be used as the oxygen concentration-related physical quantity detector instead of the oxygen concentration meter 79.

[0033] The control unit 61 is a part that controls the operation of each device that constitutes the combustion device 70. The control unit 61 is connected to the first fuel damper 74, the second fuel damper 84, and the air damper 77 by communication lines (wired or wireless; the same applies below), and is configured to be able to control the opening degree of these. The control unit 61 is also connected to the air fan 76 by a communication line, and is configured to be able to control the start and stop of the air fan 76. The control unit 61 is also connected to the two on-off valves 73 and 83 by communication lines, and is configured to be able to control the opening and closing of these. The control unit 61 is also connected to the oxygen concentration meter 79 by a communication line, and is configured to be able to receive a value measured by the oxygen concentration meter 79 as a signal. The control unit 61 has a program for appropriately operating each of the above-mentioned devices. The control unit 61 may include at least one physical configuration of a processor, a memory (RAM and / or ROM), and a storage.

[0034] The storage unit 63 is a portion in which data necessary for the operation of the combustion device 70 is stored in advance. The storage unit 63 stores a value related to the flow rate of the first fuel F1 supplied to the burner 71 and a value related to the flow rate of the air A suitable for performing appropriate combustion in the burner 71. Here, the value related to the flow rate of the first fuel F1 may be the flow rate of the first fuel F1 itself, or may be a value correlated with the flow rate of the first fuel F1 (for example, the opening degree of the first fuel damper 74). Furthermore, the value related to the flow rate of the air A may be the flow rate of the air A itself, or may be a value correlated with the flow rate of the air A (for example, the opening degree of the air damper 77). Furthermore, appropriate combustion in the burner 71 is typically combustion that does not cause problems such as incomplete combustion, generation of carbon monoxide (CO), misfire, etc., and may be combustion in which the oxygen concentration in the exhaust gas E becomes a predetermined concentration. The predetermined concentration of oxygen in the exhaust gas E that can be considered as appropriate combustion is preferably about 1% to 10%, and more preferably about 1.5% to 4%. Furthermore, the memory unit 63 stores a value related to the flow rate of the air A suitable for performing appropriate combustion in the burner 71, with respect to a value related to the flow rate of the second fuel F2 supplied to the burner 71. The value related to the flow rate of the second fuel F2 may be the flow rate of the second fuel F2 itself, or may be a value correlated with the flow rate of the second fuel F2 (for example, the opening degree of the second fuel damper 84). Furthermore, the memory unit 63 stores a plurality of patterns regarding the relationship between the distribution of the first fuel F1 and the second fuel F2 supplied to the burner 71 and the load factor (amount of combustion). The memory unit 63 may include a physical configuration of storage and / or memory (RAM and / or ROM).

[0035] 2 shows an example of the relationship between the value related to the flow rate of the first fuel F1 and the second fuel F2 supplied to the burner 71 and the value related to the flow rate of the air A for performing appropriate combustion. The relationship shown by the solid line LF1 in FIG. 2 shows the relationship between the opening degree of the first fuel damper 74 and the opening degree of the air damper 77 that supplies the air A at a flow rate that performs appropriate combustion for the opening degree of the first fuel damper 74 (hereinafter, sometimes referred to as the "first combustion table"). The relationship shown by the dashed line LF2 in FIG. 2 shows the relationship between the opening degree of the second fuel damper 84 and the opening degree of the air damper 77 that supplies the air A at a flow rate that performs appropriate combustion for the opening degree of the second fuel damper 84 (hereinafter, sometimes referred to as the "second combustion table"). The relationship shown by the solid line LF1 (first combustion table) corresponds to the first relationship, and the relationship shown by the dashed line LF2 (second combustion table) corresponds to the second relationship. The opening degree of the first fuel damper 74 corresponds to the control amount of the first adjustment mechanism, the opening degree of the second fuel damper 84 corresponds to the control amount of the second adjustment mechanism, and the opening degree of the air damper 77 corresponds to the control amount of the air flow rate adjustment mechanism. In the relationship illustrated in FIG. 2, as the opening degree of the first fuel damper 74 increases, the opening degree of the air damper 77 increases while decreasing the increase rate, but the manner of increase typically depends on the type of the first fuel F1 and / or the characteristics of the first fuel damper 74. The same applies to the relationship between the opening degree of the second fuel damper 84 and the opening degree of the air damper 77. Note that the flow rate of the fuel also increases and decreases with the increase and decrease of the opening degree of the fuel damper, and the rate of increase and decrease may be constant but may not necessarily be constant, and it should be noted that it varies depending on the characteristics of the fuel damper. For example, when the opening degree is small, the increase in the flow rate is small, and when the opening degree is large, the increase in the flow rate is large, and so on. Similarly, with respect to the air damper 77, the rate of increase or decrease in the flow rate of the air A associated with an increase or decrease in the opening degree of the air damper 77 may be, for example, small when the opening degree is small, and large when the opening degree is large, or may be constant. The first and second combustion tables are typically each determined by at least one of theory, experiment, simulation, and other techniques, and are stored in the storage unit 63 as a function or a table.For example, during a test run, an appropriate opening degree of the air damper 77 can be determined while measuring the oxygen concentration of the exhaust gas E for each opening degree of the first fuel damper 74, to create a first combustion table, which can then be stored as a function or table in the storage unit 63. The second combustion table can also be created in the same manner.

[0036] 3(A) and 3(B) show examples of the relationship between the load factor (combustion amount) of the combustion device 70 and the ratio of the consumption of the first fuel F1 and the second fuel F2. In the pattern shown in FIG. 3(A), the second fuel F2 is used preferentially, and the first fuel F1 is used to make up for the shortage. The two-dot chain line LT in FIG. 3(A) shows the total consumption of the first fuel F1 and the second fuel F2. When the pattern shown in FIG. 3(A) is applied, in this embodiment, the second fuel F2, which is hydrogen, is used as much as possible, and the first fuel F1, which is commercial gas, is used to make up for the shortage, so that the emission of carbon dioxide can be suppressed to the maximum. On the other hand, the pattern shown in FIG. 3(B) shows a pattern in which the first fuel F1 and the second fuel F2 are consumed at the same ratio regardless of the load factor. When the pattern shown in FIG. 3(B) is applied, the ratio of the first fuel F1 and the second fuel F2 supplied to the burner 71 does not change, so that it is easy to estimate an appropriate flow rate of the air A. 3(A) and 3(B) are merely examples, and other patterns may be stored in the storage unit 63. The combustion device 70 typically operates according to one pattern selected from a plurality of patterns stored in the storage unit 63. Which pattern is applied is typically determined by a user (the operator of the combustion device 70) inputting via an input device provided on a control panel attached to the combustion device 70 or a setting device such as a mobile terminal.

[0037] In addition to the above relationships, the storage unit 63 stores various relationships and data used to control the combustion device 70, which will be described later as necessary. In this embodiment, the storage unit 63 is shown as a separate entity from the control unit 61, distinguished by function for the sake of convenience, but typically the two are configured as an integrated whole, or the two may be configured as physically separate entities. The storage unit 63 may be provided in a control panel attached to the combustion device 70 together with the control unit 61, or may be provided in a location separate from the control unit 61 (for example, in a cloud computer). The storage unit 63 may be distributed in multiple locations or may be consolidated in one location, depending on the contents stored therein.

[0038] Next, a method for controlling a combustion amount according to a second embodiment will be described with reference to Fig. 4. Fig. 4 is a flow chart for explaining combustion control. In the following explanation, the control of combustion in the combustion device 70 explained thus far will be described, but the control method according to this embodiment is also applicable to devices other than the combustion device 70. This embodiment explained below as the control of combustion in the combustion device 70 also serves as an explanation of the operation of the combustion device 70. In the following explanation, when the configuration of the combustion device 70 is mentioned, reference will be made to Figs. 1 to 3(B) as appropriate.

[0039] Prior to the operation of the combustion device 70, the user selects a consumption pattern of the first fuel F1 and the second fuel F2 (for example, the patterns shown in FIG. 3(A) or FIG. 3(B)). When the combustion device 70 is operated, the control unit 61 acquires information on the amount of heat to be supplied (load factor) (St1). The load factor can typically be acquired by a signal received from a supply destination (for example, an absorption chiller / heater) to which the combustion device 70 supplies heat. After acquiring the load factor, the control unit 61 refers to the selected pattern stored in the storage unit 63, and determines the flow rate of the first fuel F1 at the load factor (St2) and determines the flow rate of the second fuel F2 (St3). For example, if the user has selected the pattern shown in FIG. 3(A), if the acquired load factor is 80%, it can be determined that the consumption amount of the first fuel F1 is 60% and the consumption amount of the second fuel F2 is 20%. In the example shown in Fig. 4, for convenience, the flow rate of the first fuel F1 is determined (St2) and then the flow rate of the second fuel F2 is determined (St3), but these are typically performed simultaneously, or the order may be reversed. In the present embodiment, the step (St2) of determining the flow rate of the first fuel F1 includes determining the opening degree of the first fuel damper 74, and the step (St3) of determining the flow rate of the second fuel F2 includes determining the opening degree of the second fuel damper 84. When the flow rate of the first fuel F1 (flow rate of the second fuel F2) and the opening degree of the first fuel damper 74 (opening degree of the second fuel damper 84) are in a proportional relationship, the opening degree of the first fuel damper 74 (the opening degree of the second fuel damper 84) can be determined by considering the ratio of the flow rate of the first fuel F1 (flow rate of the second fuel F2) to the rated flow rate as the opening degree of the first fuel damper 74 (the opening degree of the second fuel damper 84). When the flow rate of the first fuel F1 (the flow rate of the second fuel F2) and the opening degree of the first fuel damper 74 (the opening degree of the second fuel damper 84) are not in a proportional relationship, the relationship between the flow rate of the first fuel F1 (the flow rate of the second fuel F2) and the opening degree of the first fuel damper 74 (the second fuel damper 84) may be stored in advance in the memory unit 63.

[0040] 2 stored in memory unit 63, control unit 61 determines the opening degree of air damper 77 relative to the opening degree of first fuel damper 74 (St4), and determines the opening degree of air damper 77 relative to the opening degree of second fuel damper 84 (St5). At this time, the opening degree of air damper 77 relative to the opening degree of first fuel damper 74 is determined from first combustion table LF1, and the opening degree of air damper 77 relative to the opening degree of second fuel damper 84 is determined from second combustion table LF2.

[0041] After determining the opening degree of the air damper 77 for each of the opening degrees of the first fuel damper 74 and the second fuel damper 84, the control unit 61 determines the flow rate of the air A to be supplied to the burner 71 (hereinafter referred to as the "supply air flow rate") (St6). The supply air flow rate may be determined by adding a predetermined coefficient to the sum of the opening degree of the air damper 77 determined from the first combustion table LF1 and the opening degree of the air damper 77 determined from the second combustion table LF2 (hereinafter referred to as the "total air flow rate related value"). If the opening degree of the air damper 77 determined from the first combustion table LF1 is referred to as the "first air damper opening degree" and the opening degree of the air damper 77 determined from the second combustion table LF2 is referred to as the "second air damper opening degree" (same below), in this embodiment, "[the total air flow rate related value] = [the first air damper opening degree] + [the second air damper opening degree]". The reason why a predetermined coefficient is added to the total air flow rate related value is that different types of fuel, the first fuel F1 and the second fuel F2, are supplied to the burner 71 at the same time, the flow rate of the air A passing through the air damper 77 does not change in proportion to the opening degree of the air damper 77, and as shown in Fig. 2, there is no proportional relationship between the opening degree of the first fuel damper 74 (the opening degree of the second fuel damper 84) and the opening degree of the air damper 77. In this regard, if only one type of fuel is supplied to the burner 71, it is possible to determine the opening degree of the air damper 77 that can supply an appropriate flow rate of air A to the burner 71 from one combustion table (see Fig. 2). However, when there are multiple types of fuels supplied to the burner 71 at the same time, even if the opening degree of the air damper 77 for supplying air A at an appropriate flow rate for each fuel is determined individually and these are added up, the opening degree of the air damper 77 is not necessarily set to supply air A at an appropriate flow rate for all of the multiple types of fuels to the burner 71, for reasons such as the fact that the flow rate of air A is not proportional to the opening degree of the air damper 77. Therefore, in this embodiment, a predetermined coefficient is used to correct the opening degree of the air damper 77 to an appropriate opening degree. The predetermined coefficient is considered to be related to the ratio of the first fuel F1 and the second fuel F2 supplied to the burner 71, and therefore can be found, for example, in relation to the control characteristics of the first fuel damper 74 or the control characteristics of the second fuel damper 84.

[0042] FIG. 5 illustrates the relationship between the opening degree of the first fuel damper 74 and the coefficient K. The relationship illustrated in FIG. 5 can be determined typically by a test in which a fluid is actually passed through the combustion device 70. The relationship illustrated in FIG. 5 is typically stored in the storage unit 63. The shape of the curve representing the relationship between the opening degree of the first fuel damper 74 and the coefficient K illustrated in FIG. 5 can change depending on the characteristics of the air damper 77, the first fuel damper 74, and the second fuel damper 84. In the example illustrated in FIG. 5, the coefficient K is set to take a value between 0 and 1, but since the tendency differs depending on the characteristics of the air damper 77, the first fuel damper 74, and the second fuel damper 84, it can take a value larger than 1. An example in which this coefficient K is applied when calculating the supply air flow rate is shown below. In this embodiment, the supply air flow rate is the flow rate of air A supplied when the opening of air damper 77 is at a value obtained by multiplying the second air damper opening by the coefficient K (=[first air damper opening]+K×[second air damper opening]) among the total air flow rate related value (first air damper opening+second air damper opening). To give a more specific example, continuing from the above specific example, when the opening of first fuel damper 74 is 60%, the supply air flow rate is the flow rate of air A when the second air damper opening is multiplied by the coefficient K=0.65 of this opening in the relationship shown in FIG. 5 and the air damper 77 is adjusted to the opening obtained by adding this to the first air damper opening. In this way, the second air damper opening is multiplied by the coefficient related to first fuel damper 74 based on the fact that the excess or deficiency of the second air damper opening when the first air damper opening is given priority in the total air flow rate related value depends on the first air damper opening. When the second air damper opening is given priority in the total air flow rate related value, the first air damper opening may be multiplied by coefficient K for the opening of second fuel damper 84. In this way, coefficient K may be a coefficient determined in relation to second fuel damper 84, another predetermined coefficient, or a coefficient determined in relation to first fuel damper 74 and second fuel damper 84, other than one determined in relation to first fuel damper 74.Incidentally, as a method of determining coefficient K, the opening degree of first fuel damper 74 may be fixed at, for example, 20%, 40%, 60%, and 80%, and coefficient K for each case may be determined from the opening degree of air damper 77 at which the oxygen concentration of exhaust gas E becomes the predetermined concentration described above when the opening degree of second fuel damper 84 is changed for each of the opening degrees.

[0043] After the supply air flow rate is calculated, the control unit 61 judges whether or not the heat quantity (hereinafter referred to as the "total heat quantity") estimated from the previously determined flow rates (St2, St3) of the first fuel F1 and the second fuel F2 is equal to or less than the maximum heat quantity of the combustion device 70 (St7). By suppressing the total value of the heat quantity when the first fuel F1 and the second fuel F2 are combusted to be equal to or less than the maximum heat quantity of the combustion device 70, it is possible to prevent overload of the combustion device 70. Here, the maximum heat quantity of the combustion device 70 is typically a heat quantity obtained by increasing the rated value of the heat quantity of the combustion device 70 by a predetermined percentage, and the predetermined percentage can be determined within a range in which no malfunction occurs even if the combustion device 70 is operated continuously.

[0044] In step (St7), if the total heat amount is not equal to or less than the maximum heat amount (NO in St7), the flow rate (St2, St3) of the first fuel F1 and / or the second fuel F2 previously determined is corrected so that the total heat amount is equal to or less than the maximum heat amount (St8). Here, the flow rate of the first fuel F1 and / or the second fuel F2 may be corrected according to the consumption pattern of the first fuel F1 and the second fuel F2 selected before the start of operation of the combustion device 70 (for example, the pattern shown in FIG. 3(A) or FIG. 3(B)). For example, when the pattern shown in FIG. 3(A) is selected, the consumption amount of the first fuel F1 may be reduced preferentially so that the second fuel F2 is consumed to the maximum. On the other hand, when the pattern shown in FIG. 3(B) is selected, the first fuel F1 and the second fuel F2 may be reduced at the same rate. After the flow rate of the first fuel F1 and / or the second fuel F2 is corrected (St8), the process returns to step (St4), and thereafter, the control according to the above-mentioned procedure is performed.

[0045] In step (St7), if the total heat amount is equal to or less than the maximum heat amount (YES in St7), the first fuel F1 and the second fuel F2 at the determined flow rates and the air A at the supply air flow rate are supplied to the burner 71 (St9). The supply of the first fuel F1 and the second fuel F2 and the air A is performed by adjusting the openings of the first fuel damper 74, the second fuel damper 84, and the air damper 77, opening the on-off valves 73 and 83, and operating the air fan 76.

[0046] Next, the control unit 61 judges whether the measurement value of the oxygen concentration meter 79 is a predetermined value (St10). The predetermined value here is a value indicating the concentration of oxygen in the exhaust gas E when the combustion of the first fuel F1 and the second fuel F2 in the burner 71 can be considered appropriate, as described above. The predetermined concentration of oxygen in the exhaust gas E that can be considered appropriate combustion is preferably about 1% to 10%, and more preferably about 1.5% to 4%, as described above. The predetermined value may have a numerical range. If the measurement value of the oxygen concentration meter 79 is not the predetermined value in step (St10) (NO in St10), the opening degree of the air damper 77 is adjusted to correct the supply air flow rate so that the measurement value of the oxygen concentration meter 79 becomes the predetermined value (St11). By making the measurement value of the oxygen concentration meter 79 become the predetermined value, it is possible to suppress the occurrence of problems such as incomplete combustion. After correcting the supply air flow rate (St11), the process returns to step (St10) again.

[0047] When the measurement value of the oxygen concentration meter 79 is a predetermined value in step (St10) (YES in St10), the control unit 61 determines whether or not the load factor has changed (St12), typically based on a signal received from a supply destination to which the combustion device 70 supplies heat. When the load factor has not changed (NO in St12), the process returns to step (St9), and the control is performed according to the above-mentioned procedure thereafter. On the other hand, when the load factor has changed (YES in St12), the control unit 61 determines whether or not the change in the load factor is a command to stop the combustion device 70 (St13). When the command is not a command to stop the combustion device 70 (NO in St13), the process returns to step (St2), and the control is performed according to the above-mentioned procedure thereafter. On the other hand, when the command is a command to stop the combustion device 70 (YES in St13), the operation of the combustion device 70 is stopped. Note that, in the explanation of the flowchart shown in FIG. 4 so far, what has been referred to as the "flow rate" of fuel or air for convenience may be understood as the "opening degree" of a damper in actual control.

[0048] As described above, according to the combustion device 70 and the method for controlling the amount of combustion thereof, it is possible to simultaneously supply the first fuel F1 and the second fuel F2 of different types and the air A at an appropriate flow rate to the burner 71, and to burn the fuel appropriately. In addition, a plurality of consumption patterns of the first fuel F1 and the second fuel F2 are stored in the memory unit 63 in advance, and the consumption amounts of the first fuel F1 and the second fuel F2 are determined according to a pattern selected from the plurality of patterns, so that it is possible to supply the fuel in an appropriate distribution. In addition, by taking into consideration the coefficient K obtained in advance when calculating the supply air flow rate, it is possible to set the supply air flow rate according to the characteristics of the first fuel damper 74, the second fuel damper 84, and the air damper 77, and it is possible to supply the air A at a more appropriate flow rate to the burner 71. In addition, by adjusting the supply flow rate of the first fuel F1 and / or the second fuel F2 so that the total heat amount is equal to or less than the maximum heat amount, it is possible to prevent the combustion device 70 from being overloaded. In addition, by adjusting the supply air flow rate so that the measurement value of the oxygen concentration meter 79 becomes a predetermined value, the oxygen concentration contained in the exhaust gas E can be set to the desired concentration, thereby preventing problems such as incomplete combustion from occurring.

[0049] In the above description, the first fuel F1 is commercial gas and the second fuel F2 is hydrogen, but these may be reversed, or another type of fuel (for example, biomass fuel, etc.) may be used. In the above description, two types of fuel are simultaneously supplied to the burner 71, but three or more types of fuel may be simultaneously supplied to the burner 71 and combusted.

[0050] In the above description, the air flow rate adjustment mechanism is air damper 77. However, instead of air damper 77, the supply flow rate may be adjusted by varying the rotation speed of air fan 76 using an inverter or the like.

[0051] In the above description, the first relationship stored in the storage unit 63 is the relationship between the opening degree of the first fuel damper 74 and the opening degree of the air damper 77, and the second relationship is the relationship between the opening degree of the second fuel damper 84 and the opening degree of the air damper 77. However, the first relationship may be the relationship between the flow rate of the first fuel F1 and the flow rate of the air A, and the second relationship may be the relationship between the flow rate of the second fuel F2 and the flow rate of the air A. In this way, the sum of the flow rate of the air A obtained from the first relationship and the flow rate of the air A obtained from the second relationship can be set as the supply air flow rate, and the coefficient K does not need to be taken into consideration. On the other hand, if the first relationship (second relationship) is set as the relationship between the opening degree of the first fuel damper 74 (second fuel damper 84) and the opening degree of the air damper 77, it is not necessary to perform a calculation to convert the damper opening degree into a flow rate, and the opening degree of the air damper 77 to be controlled can be directly adjusted, so that the delay in the response speed can be suppressed.

[0052] In the above description, the oxygen concentration meter 79 is provided in the exhaust gas pipe 78, but if control based on the measurement value of the oxygen concentration meter 79 is not performed, the oxygen concentration meter 79 does not need to be provided (can be omitted). By omitting the oxygen concentration meter 79, the initial cost of configuring the combustion device 70 can be reduced, and the running cost can be reduced because maintenance of the oxygen concentration meter 79 is no longer necessary. When the oxygen concentration meter 79 is omitted, in the flowchart shown in Fig. 4, steps (St10) and (St11) can be omitted, and after step (St9) of supplying the first fuel F1 and the second fuel F2 and the air A to the burner 71, the process can proceed to step (St12) of determining whether or not there has been a change in the load factor.

[0053] Furthermore, if there is no concern about overloading of the combustion device 70, the step (St7) of determining whether the total heat amount is equal to or less than the maximum heat amount and the step (St8) of correcting the flow rate of the first fuel F1 and / or the second fuel F2 may be omitted in the flowchart shown in Fig. 4. In this case, after the step (St6) of calculating the supply air flow rate, the process may proceed to the step (St9) of supplying the first fuel F1 and the second fuel F2, and the air A to the burner 71.

[0054] Next, referring to FIG. 6, an absorption chiller / heater 1 according to a third embodiment will be described. FIG. 6 is a schematic system diagram of the absorption chiller / heater 1. The absorption chiller / heater 1 includes an absorber 10, an evaporator 20, a regenerator 30, and a condenser 40 as main components for performing an absorption cycle, and also includes the combustion device 70 and the control device 60. In the following description, when the configuration of the combustion device 70 is mentioned, reference will be made to FIGS. 1 to 5 as appropriate. The absorption chiller / heater 1 is a device that transfers heat by circulating a refrigerant with respect to an absorbing liquid while undergoing a phase change, and typically lowers the temperature of chilled water C as a medium to be cooled during cooling operation. In this embodiment, the absorption chiller / heater 1 is typically capable of increasing the temperature of hot water H (see FIGS. 7(A) to 7(C)) as a medium to be heated during heating operation, but will first be described as a device that performs an operation to lower the temperature of the chilled water C (hereinafter sometimes referred to as "cooling operation"), and the temperature increase of the hot water H will be described later. In the following description, the absorbing liquid is referred to as a "dilute solution Sw", a "concentrated solution Sa", etc., depending on the property and the position in the absorption cycle in order to easily distinguish them in the absorption cycle, but when the property and the like are not important, they are collectively referred to as an "absorbing liquid S". Also, the refrigerant is referred to as an "evaporator refrigerant vapor Ve", a "regenerator refrigerant vapor Vg", a "refrigerant liquid Vf", etc., depending on the property and the position in the absorption cycle in order to easily distinguish them in the absorption cycle, but when the property and the like are not important, they are collectively referred to as an "refrigerant V". In this embodiment, a lithium bromide (LiBr) aqueous solution is used as the absorbing liquid S (a mixture of an absorbent and a refrigerant), and water (H2O) is used as the refrigerant V, but the present invention is not limited to these, and other combinations of refrigerants and absorbing liquids (absorbents) may be used.

[0055] The absorber 10 is a device that absorbs the evaporator refrigerant vapor Ve generated in the evaporator 20 with a concentrated solution Sa. The absorber 10 has a cooling pipe 11 through which cooling water D flows and a concentrated solution spray nozzle 12 that sprays the concentrated solution Sa toward the outer surface of the cooling pipe 11 inside an absorber can body 17. The concentrated solution spray nozzle 12 is disposed above the cooling pipe 11 so that the sprayed concentrated solution Sa falls on the cooling pipe 11. The absorber 10 stores the dilute solution Sw, whose concentration has been reduced by the sprayed concentrated solution Sa absorbing the evaporator refrigerant vapor Ve, in the lower part of the absorber can body 17. The absorber 10 is also configured so that the cooling water D takes away (removes) the heat of absorption generated when the evaporator refrigerant vapor Ve is absorbed by the concentrated solution Sa.

[0056] A cooling water inlet pipe 11a, into which the cooling water D flows, is connected to one end of the cooling pipe 11. A cooling water connection pipe 14 is connected to the other end of the cooling pipe 11. A cooling water supply pipe 98 outside the absorption chiller / heater water machine 1 is connected to the cooling water inlet pipe 11a. The cooling water supply pipe 98 is connected to a cooling tower (not shown) outside the absorption chiller / heater water machine 1. A cooling water pump 91 outside the absorption chiller / heater water machine 1 is disposed in the cooling water supply pipe 98. The absorption chiller / heater water machine 1 is configured such that the cooling water D flows through the cooling pipe 11 by operating the cooling water pump 91. The cooling water pump 91 may be configured such that the discharge flow rate of the cooling water D can be adjusted by an inverter. The cooling water inlet pipe 11a is typically provided with a cooling water thermometer 51 for detecting the temperature of the cooling water D introduced into the cooling pipe 11.

[0057] The evaporator 20 is a device that evaporates the refrigerant liquid Vf with the heat of the cold water C to generate evaporator refrigerant vapor Ve, and cools the cold water C by removing the latent heat of evaporation required for the refrigerant liquid Vf to change phase to the evaporator refrigerant vapor Ve from the cold water C. The evaporator 20 has an evaporation tube 21 as a cold water flow path for flowing the cold water C, and a refrigerant liquid spray nozzle 22 that sprays the refrigerant liquid Vf toward the outer surface of the evaporation tube 21 inside the evaporator can body 27. The refrigerant liquid spray nozzle 22 is disposed above the evaporation tube 21 so that the sprayed refrigerant liquid Vf falls on the evaporation tube 21. The evaporator 20 further has a refrigerant liquid pipe 28 that guides the refrigerant liquid Vf stored in the lower part of the evaporator can body 27 to the refrigerant liquid spray nozzle 22, and a refrigerant pump 29 that sends the refrigerant liquid Vf in the refrigerant liquid pipe 28 to the refrigerant liquid spray nozzle 22. The evaporator 20 cools the cold water C by removing the heat of vaporization required for the refrigerant liquid Vf sprayed on the outer surface of the evaporator tube 21 to evaporate and become evaporator refrigerant vapor Ve from the cold water C flowing inside the evaporator tube 21, and is configured so that the refrigerant liquid Vf that has not evaporated is stored in the lower part of the evaporator can body 27.

[0058] A cold water inlet pipe 21a, through which cold water C flows, is connected to one end of the evaporation pipe 21. A cold water outlet pipe 21b, through which cold water C flowing out of the evaporation pipe 21 flows, is connected to the other end of the evaporation pipe 21. A cold water thermometer 52 for detecting the temperature of cold water C flowing out of the evaporation pipe 21 is provided on the cold water outlet pipe 21b. A cold water return pipe 95 outside the absorption chiller / heater 1 is connected to the cold water inlet pipe 21a. A cold water supply pipe 96 outside the absorption chiller / heater 1 is connected to the cold water outlet pipe 21b. The cold water return pipe 95 and the cold water supply pipe 96 are connected to a heat utilization device (not shown) that utilizes the cold energy contained in the cold water C. A cold water pump 92 outside the absorption chiller / heater 1 is disposed in the cold water return pipe 95. The absorption chiller / heater 1 is configured such that the cold water C flows through the evaporation pipe 21 by operating the cold water pump 92. The cold water pump 92 may be configured so that the discharge flow rate of the cold water C can be adjusted by an inverter.

[0059] In this embodiment, the absorber 10 and the evaporator 20 are disposed adjacent to each other, and an upper portion of the absorber can body 17 communicates with an upper portion of the evaporator can body 27. With this configuration, the evaporator refrigerant vapor Ve generated inside the evaporator can body 27 can be guided into the inside of the absorber can body 17.

[0060] The regenerator 30 is a device that introduces the dilute solution Sw and heats it to separate the refrigerant V in the dilute solution Sw and generate a concentrated solution Sa. In the regenerator 30, the refrigerant V separated from the dilute solution Sw is in a vapor state, and this vapor of the refrigerant V is referred to as regenerator refrigerant vapor Vg. The regenerator 30 is provided with the above-mentioned combustion device 70. The regenerator 30 also has a regenerator can body 37 that stores the introduced absorption liquid S. Inside the regenerator can body 37, a burner 71, which is one of the elements that constitute the combustion device 70, is disposed. The regenerator 30 is configured to generate heat for heating the dilute solution Sw by burning the first fuel F1 and the second fuel F2 with the burner 71.

[0061] The condenser 40 is a device that introduces the regenerator refrigerant vapor Vg evaporated from the dilute solution Sw in the regenerator 30, cools and condenses it, and generates the refrigerant liquid Vf to be sent to the evaporator 20. The condenser 40 has a condenser tube 41, which is a member that forms a flow path of the cooling water D, inside the condenser can body 47. In this embodiment, one end of the condenser tube 41 is connected to the other end of the cooling water communication tube 14, one end of which is connected to the cooling tube 11. The other end of the condenser tube 41 is connected to a cooling water outlet tube 41b through which the cooling water D flowing out from the condenser tube 41 flows. A cooling water return tube 99 outside the absorption chiller / heater 1 is connected to the cooling water outlet tube 41b. The cooling water return tube 99 is connected to a cooling tower (not shown) outside the absorption chiller / heater 1. With this configuration, the cooling water D flowing through the cooling water return tube 99 is cooled in the cooling tower (not shown) and supplied to the cooling water supply tube 98.

[0062] The condenser can body 47 is disposed close to the regenerator can body 37. In this embodiment, the upper part of the regenerator can body 37 and the upper part of the condenser can body 47 are connected via the regenerator refrigerant vapor passage 35. The condenser 40 is configured to introduce the regenerator refrigerant vapor Vg from the regenerator 30 via the regenerator refrigerant vapor passage 35, and condense the regenerator refrigerant vapor Vg into refrigerant liquid Vf by removing heat from the regenerator refrigerant vapor Vg with the cooling water D flowing through the condensation tube 41. In other words, the cooling water D flowing through the condensation tube 41 removes the condensation heat generated when the regenerator refrigerant vapor Vg changes phase to the refrigerant liquid Vf. In this embodiment, the condenser can body 47 and the regenerator can body 37 are disposed above the evaporator can body 27 and the absorber can body 17. The bottom or lower part of the condenser body 47 and the evaporator body 27 are connected by a condensed refrigerant liquid pipe 48, so that the refrigerant liquid Vf in the condenser body 47 can be guided into the evaporator body 27 by the position head and the internal pressure difference between the two.

[0063] The bottom or lower part of the absorber can body 17 and the regenerator can body 37 are connected by a dilute solution pipe 18. A solution pump 19 is disposed in the dilute solution pipe 18. The absorption chiller / heater 1 is configured to convey the dilute solution Sw in the absorber can body 17 into the regenerator can body 37 by the solution pump 19. In the regenerator can body 37, as the introduced dilute solution Sw moves from the inlet to the outlet, the refrigerant V is separated from the dilute solution Sw, and the concentration increases. The part of the regenerator can body 37 from which the concentrated solution Sa flows out is connected to the concentrated solution spray nozzle 12 of the absorber 10 by a concentrated solution pipe 38. The absorption chiller / heater 1 is configured to convey the dilute solution Sw to the regenerator can body 37 by the solution pump 19, and the concentrated solution Sa generated by the separation of the refrigerant V in the regenerator can body 37 is introduced into the concentrated solution spray nozzle 12 via the concentrated solution pipe 38. A solution heat exchanger 81 is inserted into the dilute solution pipe 18 and the concentrated solution pipe 38 to exchange heat between the dilute solution Sw flowing through the dilute solution pipe 18 and the concentrated solution Sa flowing through the concentrated solution pipe 38.

[0064] The control device 60 is a device that controls the operation of the absorption chiller-heater machine 1. The control device 60 has a control unit 61 and a storage unit 63. In this embodiment, the control unit 61 and the storage unit 63 also serve as the control unit 61 and the storage unit 63 of the combustion device 70. In other words, in this embodiment, the control unit 61 and the storage unit 63 of the combustion device 70 of the absorption chiller-heater machine 1 also control the operation of each device and equipment constituting the absorption chiller-heater machine 1. Although the control unit 61 and the storage unit 63 are shown as being distinguished by their functions for the sake of convenience in this embodiment, they are typically configured as an integrated unit within the control device 60, or the two parts may be configured as being physically separate.

[0065] The control unit 61 is connected to the solution pump 19, the refrigerant pump 29, the cooling water pump 91, and the cold water pump 92 by communication lines, and is configured to be able to control the start / stop and discharge flow rate of these. The control unit 61 is also connected to the cooling water thermometer 51 and the cold water thermometer 52 by communication lines, and is configured to be able to receive the temperature of the cooling water D from the cooling water thermometer 51 and the temperature of the cold water C from the cold water thermometer 52. As described above, the control unit 61 controls each device constituting the above-mentioned combustion device 70. The control unit 61 typically has a program for properly operating each of the above-mentioned devices and devices. The memory unit 63 stores the upper limit of the combustion amount of the first fuel F1 and the second fuel F2 in the burner 71 of the regenerator 30 to maintain proper operation of the absorption chiller-heater 1 (operation within a range that prevents excessive heat input (overload)).

[0066] The operation of the absorption chiller / heater 1 will be described with continued reference to FIG. 6. In the following description, when the configuration of the combustion device 70 is mentioned, reference will be made to FIGS. 1 to 5 as appropriate. When the absorption chiller / heater 1 is started and the cooling water pump 91 is operated, the cooling water D in this embodiment flows and circulates through the cooling water supply pipe 98, the cooling water inlet pipe 11a, the cooling pipe 11, the cooling water connection pipe 14, the condenser pipe 41, the cooling water outlet pipe 41b, the cooling water return pipe 99, and the cooling tower (not shown). When the cold water pump 92 is operated, the cold water C flows and circulates through the cold water return pipe 95, the cold water inlet pipe 21a, the evaporation pipe 21, the cold water outlet pipe 21b, the cold water supply pipe 96, and the heat utilization equipment (not shown).

[0067] Regarding the absorption cycle, looking at the cycle on the refrigerant V side, the regenerator refrigerant vapor Vg introduced into the condenser 40 from the regenerator 30 via the regenerator refrigerant vapor passage 35 is cooled and condensed by the cooling water D flowing through the condenser tube 41, and becomes refrigerant liquid Vf, which is stored in the lower part of the condenser body 47. The cooling water D that has cooled the regenerator refrigerant vapor Vg increases in temperature and flows out of the cooling water return pipe 99 and is supplied to a cooling tower (not shown). The refrigerant liquid Vf in the condenser body 47 is introduced into the evaporator body 27 via the condensed refrigerant liquid pipe 48.

[0068] The refrigerant liquid Vf introduced from the condenser can body 47 to the evaporator can body 27 is mixed with the refrigerant liquid Vf that was sprayed from the refrigerant liquid spray nozzle 22 and did not evaporate, and is stored in the lower part of the evaporator can body 27. The refrigerant liquid Vf in the evaporator can body 27 flows through the refrigerant liquid pipe 28 by the refrigerant pump 29 and reaches the refrigerant liquid spray nozzle 22. The refrigerant liquid Vf that reaches the refrigerant liquid spray nozzle 22 is sprayed toward the evaporation tube 21, and a part of it evaporates by obtaining heat from the cold water C flowing through the evaporation tube 21 to become the evaporator refrigerant vapor Ve, and is introduced into the absorber can body 17. The cold water C that has absorbed heat from the sprayed refrigerant liquid Vf is reduced in temperature and flows out of the evaporation tube 21, and is supplied to a heat utilization device (not shown) such as an air conditioner. The refrigerant liquid Vf that was sprayed from the refrigerant liquid spray nozzle 22 and did not evaporate is mixed with the refrigerant liquid Vf introduced from the condenser can body 47 and is stored in the lower part of the evaporator can body 27.

[0069] Next, looking at the cycle on the solution S side of the absorption chiller / heater 1, the dilute solution Sw in the absorber can body 17 flows through the dilute solution pipe 18 by the solution pump 19, and after the temperature is increased in the solution heat exchanger 81, it is introduced into the regenerator can body 37. The dilute solution Sw introduced into the regenerator can body 37 is heated by the combustion heat when the first fuel F1 and the second fuel F2 are burned in the burner 71, and the refrigerant V is separated to become the concentrated solution Sa. The refrigerant V heated by the combustion heat and separated from the dilute solution Sw is sent as the regenerator refrigerant vapor Vg to the condenser can body 47 through the regenerator refrigerant vapor flow path 35. The concentrated solution Sa generated in the regenerator can body 37 flows through the concentrated solution pipe 38, and reaches the concentrated solution spray nozzle 12 after heat exchange with the dilute solution Sw in the solution heat exchanger 81 to lower its temperature.

[0070] The concentrated solution Sa that reaches the concentrated solution spray nozzle 12 is sprayed toward the cooling pipe 11, where it absorbs the evaporator refrigerant vapor Ve introduced from the evaporator 20, decreasing its concentration and becoming a dilute solution Sw. When the concentrated solution Sa absorbs the evaporator refrigerant vapor Ve in the absorber can body 17, heat of absorption is generated. This generated heat of absorption is removed by the cooling water D flowing through the cooling pipe 11. In this embodiment, the cooling water D flowing through the cooling pipe 11 removes the heat of absorption, increases in temperature, and flows out into the cooling water connection pipe 14 and is supplied to the condenser pipe 41 of the condenser 40. The dilute solution Sw generated in the absorber can body 17 is stored in the absorber can body 17.

[0071] When the absorption cycle of the absorbing liquid S and the refrigerant V is being performed as described above, the control device 60 issues a command to the combustion device 70 to control the combustion amount described above so that the temperature of the chilled water C (typically the temperature detected by the chilled water thermometer 52) becomes a target value. Typically, the above-mentioned signal relating to the load factor received by the combustion device 70 from the supply destination to which heat is supplied becomes a signal relating to the thermal load to be processed so that the temperature of the chilled water C in the absorption chiller-heater 1 becomes a target value. The control of the combustion amount in the combustion device 70 may be, for example, the control shown in the flowchart of FIG. 4.

[0072] In this embodiment, when the temperature of the cold water C in the absorption chiller / heater 1 is controlled to be a target value, an upper limit is set on the amount of combustion of the fuel (first fuel F1 and / or second fuel; the same applies below) in the burner 71 of the regenerator 30. As described above, in the regenerator 30, the dilute solution Sw is heated by the heat of combustion in the burner 71 to generate a concentrated solution Sa, and the greater the amount of combustion (amount of heat), the greater the amount of evaporation of the refrigerant V in the dilute solution Sw, and the higher the concentration of the concentrated solution Sa to be generated. However, if the concentration of the concentrated solution Sa becomes too high, the absorption solution S may crystallize, causing poor flow of the absorption solution S, and it may become difficult to maintain proper operation of the absorption chiller / heater 1 (operation within a range that prevents excessive heat input (overload)). Therefore, the control unit 61 compares the combustion amount in the burner 71 when the fuel supply flow rate to the burner 71 is adjusted so that the temperature of the cold water C becomes the target value with the set upper limit combustion amount, and controls the first fuel damper 74 and the second fuel damper 84 so as to operate the burner 71 with the smaller combustion amount. The upper limit combustion amount may be set to a combustion amount for the temperature or pressure of the regenerator 30 (inside the regenerator can body 37) or the concentration of the strong solution Sa to become a target value, and this target value should be a value that provides a combustion amount that provides a heating amount that results in a concentration that is a margin lower than the concentration at which the strong solution Sa crystallizes. Setting the upper limit combustion amount in this way makes it possible to prevent the strong solution Sa from increasing to a concentration at which it crystallizes.

[0073] In the above description of the absorption chiller-heater 1, the temperature of the chilled water C is directly measured using the chilled water thermometer 52 to check whether the chilled water C is at the target temperature. However, instead of directly measuring the temperature of the chilled water C, the temperature of the chilled water C may be estimated from the evaporation temperature of the refrigerant liquid Vf in the evaporator 20 (inside the evaporator can body 27), the evaporation pressure of the refrigerant liquid Vf in the evaporator 20 (inside the evaporator can body 27) which is correlated with the evaporation temperature of the refrigerant liquid Vf, or the pressure in the absorber 10 (inside the absorber can body 17) which is in communication with the evaporator 20 and has substantially the same value as the evaporation pressure. If such an alternative means is used, the chilled water thermometer 52 can be omitted.

[0074] In the above description of the absorption chiller-heater 1, the absorption cycle is a single-effect one, but a high-temperature regenerator may be provided to make it a double-effect or triple-effect or more multiple-effect one.

[0075] In the above description, the function of lowering the temperature of the cold water C as a medium to be cooled in the absorption chiller / heater water machine 1 has been mentioned, but by switching the mode (for example, switching between the cooling mode and the heating mode), it is possible to raise the temperature of the hot water H (see Figs. 7(A) to 7(C)) as a medium to be heated. There are a number of modes of operation for raising the temperature of the hot water H in the absorption chiller / heater water machine 1 (hereinafter sometimes referred to as "heating operation"), for example as shown in Figs. 7(A) to 7(C). Note that, in any mode of operation for raising the temperature of the hot water H, although additional piping or other configurations may be required, the basic configuration of the device can use the configuration of the absorption chiller / heater water machine 1 shown in Fig. 6. Therefore, for configurations that are omitted and not shown in Figs. 7(A) to 7(C), refer to Fig. 6.

[0076] In the first hot water generation form shown in FIG. 7(A), heat source water U is supplied to the evaporation tube 21 of the evaporator 20, and hot water H as a medium to be heated is flowed through the cooling tube 11 of the absorber 10 and the condensation tube 41 of the condenser 40. At this time, the absorption liquid S and the refrigerant V flow in a cycle similar to that in the case of cooling the cold water C. In addition, the heat source water U flowing through the evaporation tube 21 is supplied to give the refrigerant liquid Vf flowing into the evaporator 20 latent heat of evaporation. The hot water H flowing as described above is first heated by the absorption heat in the absorber 10, and then heated by the condensation heat in the condenser 40 and supplied to a heat utilization device (not shown). In this form, the absorber 10 corresponds to the absorption section, and the condenser 40 corresponds to the condensation section. In this embodiment in which hot water H is produced, the flow path of the temperature-adjusted medium (cold water C, hot water H) in the absorption chiller-heater 1 is changed from the evaporation pipe 21 in the case of cold water C to a flow path including the cooling pipe 11 and the condenser pipe 41, so that piping, a switching valve, etc. (not shown) for switching the flow path of the temperature-adjusted medium are installed. Also, since heat source water U flows in place of cold water C (temperature-adjusted medium) when cold water C is produced in the evaporation pipe 21, piping, a switching valve, etc. (not shown) for switching these flow paths are installed.

[0077] In the operation for generating the hot water H, the amount of fuel combustion in the burner 71 is adjusted so that the supply temperature (outlet temperature) of the hot water H becomes the target temperature. The relationship between the opening degree of the first fuel damper 74 (flow rate of the first fuel F1) and the second fuel damper 84 (flow rate of the second fuel F2) and the opening degree of the air damper 77 (flow rate of the air A) is not different in the heating operation from that in the cooling operation, and the relationship shown in FIG. 2 can be used. Also in this embodiment, the absorption chiller-heater 1 is controlled in the same way as in the cooling operation. In the description here, the hot water H is heated by the absorption heat in the absorber 10 and the condensation heat in the condenser 40, but it may be heated by either the absorption heat or the condensation heat.

[0078] In the second hot water generation form shown in FIG. 7(B), hot water H is made to flow through the evaporation tube 21 of the evaporator 20, and the regenerator refrigerant vapor Vg generated in the regenerator 30 is guided to the evaporator 20 and condensed, and the hot water H flowing through the evaporation tube 21 is heated by the condensation heat of the regenerator refrigerant vapor Vg in the evaporator 20. In this form, the evaporator 20 functions as a condenser and corresponds to a condensing section. In this form, the cold water C in the cooling operation and the hot water H in the heating operation flow through the same evaporation tube 21, so there is an advantage that it is not necessary to switch the system of the temperature adjustment target medium (cold water C, hot water H). However, in the case of this modification, a regenerator refrigerant vapor flow path 135 is additionally provided to guide the regenerator refrigerant vapor Vg from the regenerator 30 to the evaporator 20. The refrigerant liquid Vf generated by condensing the regenerator refrigerant vapor Vg in the evaporator 20 may be sent to the absorber 10, mixed with the absorbing liquid S, and returned to the regenerator 30 via the dilute solution pipe 18 as the dilute solution Sw. In this case, the system of the absorbing liquid S can be operated in the same manner as in the embodiment shown in FIG. 7(A), but a refrigerant liquid pipe 118 for leading the refrigerant liquid Vf of the evaporator 20 to the absorber 10 is additionally provided. Alternatively, although not shown, the refrigerant liquid Vf generated by condensing the regenerator refrigerant vapor Vg in the evaporator 20 may be returned directly to the regenerator 30. In this case, it is preferable to stop the operation of the system of the absorbing liquid S. In this embodiment, the opening degree of the first fuel damper 74 and the second fuel damper 84 is adjusted so that the temperature of the hot water H becomes the target temperature, and the opening degree of the air damper 77 is adjusted so that the air A at the calculated supply air flow rate is supplied to the burner 71, thereby adjusting the flow rate of the air A, similar to the embodiment shown in FIG. 7(A).

[0079] In the third hot water generation form shown in FIG. 7(C), hot water H is made to flow through the evaporation tube 21 of the evaporator 20, and the regenerator refrigerant vapor Vg and the concentrated solution Sa generated in the regenerator 30 are separately introduced to the evaporator 20, and the hot water H flowing through the evaporation tube 21 is heated by the heat of absorption when the concentrated solution Sa absorbs the regenerator refrigerant vapor Vg in the evaporator 20. In this form, the evaporator 20 functions as an absorber and corresponds to an absorption section. In this form, the cold water C in the cooling operation and the hot water H in the heating operation flow through the same evaporation tube 21, so there is an advantage that it is not necessary to switch the system of the temperature-adjusted medium (cold water C, hot water H). However, in the case of this modified example, in addition to the regenerator refrigerant vapor flow path 135 similar to the form shown in FIG. 7(B), a concentrated solution pipe 138 that introduces the concentrated solution Sa from the regenerator 30 to the evaporator 20 is additionally provided. The dilute solution Sw generated when the concentrated solution Sa absorbs the regenerator refrigerant vapor Vg in the evaporator 20 may be sent to the absorber 10 and then returned to the regenerator 30 via the dilute solution pipe 18. In this case, a dilute solution pipe 128 for guiding the dilute solution Sw from the evaporator 20 to the absorber 10 is additionally provided. In this embodiment, the openings of the first fuel damper 74 and the second fuel damper 84 are adjusted so that the temperature of the hot water H becomes a target temperature, and the opening of the air damper 77 is adjusted so that air A at the calculated supply air flow rate is supplied to the burner 71 to adjust the flow rate of air A, similar to the embodiment shown in FIG. 7(A).

[0080] As another form of hot water generation, although not shown in the figures, the absorption cycle between the absorption liquid S and the refrigerant V may be stopped and the hot water H may be heated by the combustion heat of the burner 71. In this case, a pipe for flowing the hot water H is disposed at a position where the hot water H can be heated by the combustion heat of the burner 71. In this case, since the temperature of the hot water H can be adjusted by the combustion heat of the burner 71, the amount of fuel combustion (opening degree of the first fuel damper 74 and the second fuel damper 84) may be adjusted so that the temperature of the hot water H becomes the target temperature, and air A may be supplied to the burner 71 accordingly.

[0081] The absorption chiller / heater in this disclosure has been described as being capable of producing cold water C and hot water H by switching between modes. However, it is clear that the characteristic parts of this disclosure can be applied to equipment dedicated to producing cold water (absorption chillers) and equipment dedicated to producing hot water (absorption heat pumps). Therefore, the concept of the absorption chiller / heater in this disclosure includes absorption chillers and absorption heat pumps. [Explanation of symbols]

[0082] 1 Absorption chiller / heater 10 Absorber 20 Evaporator 30 Regenerator 40 Condenser 61 Control section 63 Memory section 70 Combustion Equipment 71 Burner 72 First fuel supply pipe (first supply mechanism) 74 First fuel damper (first adjustment mechanism) 75 Air supply pipe (air supply mechanism) 76 Air fan (air supply mechanism) 77 Air damper (air flow control mechanism) 78 Exhaust gas pipe 79 Oxygen concentration meter (Oxygen concentration related physical quantity detector) 82 Second fuel supply pipe (second supply mechanism) 84 Second fuel damper (second adjustment mechanism) A. Air C. Chilled water (cooling medium) E Exhaust Gas F1 1st fuel F2 2nd fuel H Hot water (medium to be heated) S Absorbing liquid U Heat source water V Refrigerant

Claims

1. Burner and, A first supply mechanism for supplying a first fuel to the burner, the first supply mechanism having a first adjustment mechanism for adjusting the flow rate of the first fuel supplied to the burner, A second supply mechanism for supplying a second fuel of a different type from the first fuel to the burner, the second supply mechanism having a second adjustment mechanism that operates independently of the first adjustment mechanism to adjust the flow rate of the second fuel supplied to the burner, An air supply mechanism for supplying air to the burner, comprising an air flow rate adjustment mechanism that operates independently of the first adjustment mechanism and the second adjustment mechanism to adjust the flow rate of air supplied to the burner, A storage unit that stores a first relationship defining a value related to the air flow rate corresponding to a value related to the flow rate of the first fuel supplied to the burner, and a second relationship defining a value related to the air flow rate corresponding to a value related to the flow rate of the second fuel supplied to the burner, The system includes a control unit that controls the airflow rate adjustment mechanism to supply the burner with a supply airflow rate that is based on a total airflow rate related value obtained by summing a value related to the airflow rate obtained from the first relationship and a value related to the airflow rate obtained from the second relationship, The first relationship is defined by the relationship between the control amount of the first adjustment mechanism and the control amount of the airflow adjustment mechanism. The second relationship described above is defined by the relationship between the control amount of the second adjustment mechanism and the control amount of the airflow adjustment mechanism. The aforementioned total airflow-related value is the sum of the control amount of the airflow control mechanism obtained from the first relationship and the control amount of the airflow control mechanism obtained from the second relationship. The supplied air flow rate is the air flow rate corresponding to the control amount of the air flow control mechanism, obtained by adding at least one of a coefficient determined in relation to the control characteristics of the first control mechanism and a coefficient determined in relation to the control characteristics of the second control mechanism to at least one of the control amount of the air flow control mechanism determined from the first relationship in the total air flow rate related value and the control amount of the air flow control mechanism determined from the second relationship. Combustion device.

2. The control unit controls at least one of the first adjustment mechanism and the second adjustment mechanism so that the sum of the heat generated when the first fuel is burned and the heat generated when the second fuel is burned is less than or equal to the maximum heat allowed by the combustion device. The combustion apparatus according to claim 1.

3. The system includes an oxygen concentration-related physical quantity detector that detects a physical quantity related to the oxygen concentration contained in the exhaust gas produced by burning at least one of the first fuel and the second fuel, The control unit controls the airflow rate adjustment mechanism so that the physical quantity detected by the oxygen concentration-related physical quantity detector reaches a predetermined value. The combustion apparatus according to claim 1.

4. The storage unit stores multiple patterns regarding the distribution of the first fuel and the second fuel with respect to the amount of heat required by the combustion device. The control unit controls the first adjustment mechanism and the second adjustment mechanism according to one pattern selected from the plurality of stored patterns. The combustion apparatus according to claim 1.

5. An absorption chiller / heater having a combustion device according to any one of claims 1 to 4, A regenerator having at least the burner of the combustion device, which uses the heat generated by the burner to evaporate the refrigerant contained in the absorbent liquid and increase the concentration of the absorbent liquid, A condenser that cools the refrigerant vapor introduced from the regenerator to convert it into liquid refrigerant, The system comprises an evaporator that cools a medium to be cooled by removing the latent heat of vaporization from the medium to be cooled by the liquid refrigerant introduced from the condenser, The control unit compares the amount of combustion in the burner required to bring the cooling medium to a target temperature with the upper limit of the amount of combustion in the burner required to maintain proper operation of the absorption chiller, and operates the combustion device at the smaller of the two amounts of combustion. Absorption chiller / heater.

6. An absorption chiller / heater having a combustion device according to any one of claims 1 to 4, A regenerator having at least the burner of the combustion device, which uses the heat generated by the burner to evaporate the refrigerant contained in the absorbent liquid and increase the concentration of the absorbent liquid, A condenser unit that condenses the refrigerant vapor introduced from the regenerator into a liquid refrigerant, The absorbent liquid comprises an absorbent section that absorbs the vapor of the refrigerant, The heating medium is heated by at least one of the heat of condensation generated when the refrigerant vapor condenses in the condensing section and the heat of absorption generated when the refrigerant vapor is absorbed by the absorbent liquid in the absorption section. The control unit compares the amount of combustion in the burner required to bring the heating medium to a target temperature with the upper limit of the amount of combustion in the burner required to maintain proper operation of the absorption chiller, and operates the combustion device at the smaller of the two amounts of combustion. Absorption chiller / heater.

7. A step of determining the flow rate of the first fuel to be supplied to the burner, A step of determining the flow rate of a second fuel, which is of a different type from the first fuel, to be supplied to the burner, A step of determining, from a predetermined first relationship, a control amount for an air flow rate adjustment mechanism that adjusts the flow rate of air supplied to the burner, which is related to the flow rate of air corresponding to the flow rate of the first fuel supplied to the burner, A step of determining a control amount for the airflow control mechanism related to the airflow rate corresponding to the flow rate of the second fuel supplied to the burner, based on a predetermined second relationship, A step of determining the air flow rate to be supplied to the burner, which corresponds to the air flow rate of the air flow control mechanism obtained by adding at least one of the coefficients obtained in relation to the control characteristics of the first adjustment mechanism that adjusts the flow rate of the first fuel and the coefficient obtained in relation to the control characteristics of the second adjustment mechanism that adjusts the flow rate of the second fuel to at least one of the total air flow rate related value obtained by summing the control amount of the air flow control mechanism obtained from the first relationship and the control amount of the air flow control mechanism obtained from the second relationship, The process includes supplying the first fuel, the second fuel, and the air to the burner in predetermined flow rates, respectively. A method for controlling the amount of combustion.

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