JP5018715B2 - Waste heat recovery device - Google Patents

Description

  The present invention relates to a waste heat recovery apparatus that recovers waste heat from a heat source.

  Conventionally, waste heat recovery apparatuses described in Patent Documents 1 to 6 are known. These waste heat recovery apparatuses use an internal combustion engine as a power source for driving an automobile as a heat source. The waste heat recovery device recovers waste heat contained in the exhaust gas of the internal combustion engine into engine cooling water.

The waste heat recovery apparatuses described in Patent Documents 1 and 2 include a circulation type heat pipe. The waste heat recovery apparatuses described in Patent Documents 3 to 6 include a control device that adjusts the flow rate of cooling water passing through the waste heat recovery apparatus. Furthermore, the waste heat recovery apparatuses described in Patent Documents 5 and 6 disclose a control apparatus that limits the flow rate of cooling water in order to warm up the catalyst.
JP 2007-212075 A JP 2008-51479 A Japanese Utility Model Publication No. 59-52061 Japanese Patent Laid-Open No. 61-295118 JP 2008-190437 A JP 2008-190439 A

  According to the waste heat recovery apparatuses described in Patent Documents 1 and 2, the fluid in the heat pipe is interposed as an intermediate medium between the exhaust gas as the waste heat medium and the cooling water as the utilization medium. This configuration has an advantage that a temperature difference between the exhaust gas and the cooling water can be allowed. However, the heat pipe sometimes takes heat of the cooling water immediately after starting due to its own heat capacity. Further, the heat capacity of the heat pipe sometimes hinders a temperature increase immediately after the start of the device belonging to the exhaust system. Furthermore, in order to maintain the normal function of a device such as a heat pipe, it is necessary to avoid that the intermediate medium reaches an abnormal state such as excessive temperature or excessive pressure.

  On the other hand, in the waste heat recovery apparatus described in Patent Documents 3 to 6, the state of the intermediate medium in the heat pipe used in the waste heat recovery apparatus is not considered. For this reason, when combined with a heat pipe, the intermediate medium in the heat pipe may not be maintained in an appropriate state.

  An object of this invention is to provide the waste-heat recovery apparatus which can maintain the intermediate medium in a heat pipe in a suitable state in view of the said problem.

  Another object of the present invention is to provide a waste heat recovery apparatus capable of executing a warm-up operation immediately after a heat source is activated while maintaining an intermediate medium in a heat pipe in an appropriate state. And

  In order to achieve the above object, the following technical means can be employed.

According to one aspect of the present invention, thermally connected via an intermediate medium and the exhaust system (22) and use the medium flows available system (23) through which exhaust gas flows of the internal combustion engine or an external combustion engine (2) the waste heat recovery device that Ru incorporated thermal said utilization system of exhaust system (40), and adjusting the opening of the passage of available media, regulating valve for adjusting the flow rate of the available media to be supplied to the waste heat recovery equipment (46) and during the warm-up period, the opening of the control valve is adjusted to the restricted state, and the temperature or pressure of the intermediate medium reaches the use medium control value (TH1) during the warm-up period of the waste heat recovery unit. Then, a technical means called a waste heat recovery device is provided, which includes a control device (47) for adjusting the opening of the control valve to a release state larger than the restriction state.

According to the present invention, during the warm-up period of the waste heat recovery device, the opening degree of the control valve (46) is adjusted to the restricted state. For this reason, during the warm-up period, it is possible to suppress the amount of heat taken out from the utilization system (23). Further, when the temperature or pressure of the intermediate medium reaches the utilization medium control value (TH1) during the warm-up period, the opening degree of the adjustment valve (46) is adjusted to a release state larger than the limit state. For this reason, it can be avoided that the intermediate medium reaches an abnormal state such as excessively high temperature or excessively high pressure.

According to the second aspect of the present invention, the waste heat recovery device (40) includes an evaporation unit provided in the exhaust system, a condensing unit provided in the utilization system, and a steam passage connecting the evaporation unit and the condensing unit. A circulation type comprising: a circulation passage including a liquid passage; and a circulation restriction valve (45) provided in the liquid passage and restricting the opening of the liquid passage when the temperature or pressure of the intermediate medium reaches the intermediate medium control value (TH2). Adopt the technical means of being a heat pipe.

  The invention according to claim 3 employs technical means that the use medium control value is a temperature or a pressure lower than the intermediate medium control value.

The invention according to claim 4 employs a technical means in which the control device gradually increases the opening degree of the control valve in the restricted state as the warm-up of the waste heat recovery device progresses. .

  The invention according to claim 5 employs technical means characterized in that the restricted state is a small opening range that does not include full opening.

  The invention according to claim 6 employs a technical means characterized in that the release state is a large opening range including full opening.

  The invention according to claim 7 employs technical means in which the control device further adjusts the opening degree of the control valve to the released state after the warm-up period.

  According to an eighth aspect of the present invention, the control device includes a sensor (48) for detecting the temperature or pressure of the intermediate medium, and an electric control device (49) for inputting the detection signal of the sensor and driving the control valve. Adopt technical means characterized by providing.

  In addition, the code | symbol in the parenthesis as described in a claim and said each means shows the correspondence with the specific means as described in embodiment mentioned later as one aspect.

(First embodiment)
Hereinafter, a first embodiment in which the present invention is applied to a waste heat recovery device 4 of an in-vehicle device 1 mounted on a vehicle will be described. FIG. 1 is a block diagram showing the configuration of the in-vehicle device 1. The in-vehicle device 1 includes a heat source 2, a heat utilization device 3, and a waste heat recovery device 4.

  The heat source 2 is an internal combustion engine 2 that is also a power source of the vehicle. The internal combustion engine 2 is also simply called an engine EG. The engine 2 includes a main body 21, an exhaust system 22 extending from the main body 21, and a cooling water system 23. The waste heat medium is exhaust gas. The exhaust system 22 is also called a waste heat system. The exhaust system 22 has an exhaust pipe for flowing exhaust gas. A catalyst 24 for purifying exhaust gas is disposed in the exhaust system 22. The utilization medium is cooling water. The cooling water system 23 is also called a utilization system. The cooling water system 23 constitutes a circulation path including the main body 21. A pump driven by the main body 21 or an electric pump is provided in this circulation path.

  The heat utilization device 3 is a device that utilizes the heat of the cooling water flowing through the cooling water system 23 of the engine 2. The heat utilization device 3 is also called a hot water device HWD. The heat utilization device 3 can be incorporated in the cooling water system 23 of the engine 2 in series. The heat utilization device 3 can include at least one of a heat exchanger for a vehicle heating device, a hot water tank for an engine warm-up device, and a heat exchanger for cooling the engine 2. In a typical embodiment, the heat utilization device 3 can include a heat exchanger for a heating device and a heat exchanger for cooling the engine 2.

  The waste heat recovery device 4 is incorporated between the cooling water system 23 of the engine 2 and the exhaust system 22 of the engine 2. The waste heat recovery device 4 mainly takes in the heat of the exhaust system into the cooling water system. The heat taken in by the waste heat recovery device 4 is supplied to the heat utilization device 3. As a result, the heat utilization device 3 can utilize both the heat of the cooling water supplied from the engine 2 and the heat taken in by the waste heat recovery device 4. The heat taken in by the waste heat recovery device 4 can also be used for heating the engine 2.

  The waste heat recovery device 4 includes a waste heat recovery device 40. The waste heat recovery unit 40 thermally connects the engine exhaust system 22 and the engine cooling water system 23 via an intermediate medium. The waste heat recovery unit 40 is a circulation type heat pipe, and an intermediate medium that can be changed into a gas phase and a liquid phase by a temperature difference in the waste heat recovery unit 40 is enclosed therein. The intermediate medium is also called a heat pipe medium. The waste heat recovery device 40 includes an evaporation unit 41 provided in the exhaust system 22, a condensing unit 42 provided in the cooling water system 23, and a circulation passage connecting the evaporation unit 41 and the condensing unit 42. The circulation passage includes a steam passage 43 and a liquid passage 44. Further, the waste heat recovery device 40 includes a circulation restriction valve 45 provided in the liquid passage 44. The evaporator 41 boiles and evaporates the intermediate medium by exchanging heat with the exhaust gas. The condensation unit 42 condenses and liquefies the intermediate medium by exchanging heat with the cooling water. The vapor passage 43 supplies the vapor of the intermediate medium evaporated by the evaporation unit 41 to the condensing unit 42. The liquid passage 44 supplies the liquid of the intermediate medium condensed by the condensing unit 42 to the evaporation unit 41.

  The circulation restriction valve 45 restricts the opening degree of the liquid passage 44 when the temperature or pressure of the intermediate medium reaches the second control value TH2. The second control value TH2 is also called an intermediate medium control value for controlling the intermediate medium. The circulation restriction valve 45 includes a pressure sensitive member such as a diaphragm that senses the pressure of the intermediate medium in the waste heat recovery unit 40, and a valve that opens and closes the liquid passage 44 by the displacement of the pressure sensitive member. Regarding the configuration of the circulation restriction valve 45, the contents of the prior art documents can be referred to. When the circulation restriction valve 45 restricts the opening degree of the liquid passage 44, the evaporation of the intermediate medium in the evaporation unit 41 is reduced, and the heat recovery from the exhaust gas is reduced. As a result, the heat recovery operation is stopped. The second control value TH2 of the circulation restriction valve 45 is set so as to avoid an excessive increase in the pressure of the intermediate medium or an excessive increase in the temperature of the cooling water.

  The waste heat recovery device 4 further includes a control valve 46 and a control device 47. The adjustment valve 46 adjusts the opening degree of the cooling water passage connected to the condensing part 42 of the waste heat recovery device 40. The control valve 46 is provided in the entrance side passage of the condensing unit 42. The adjustment valve 46 can continuously adjust the opening of the passage from the fully closed state to the fully open state. The control device 47 includes a sensor 48 that detects the pressure of the intermediate medium, and an electrical control device 49 that inputs a detection signal of the sensor 48 and drives the adjustment valve 46. The electric control device 49 is also called an electric control unit ECU. The sensor 48 detects the pressure of the intermediate medium and outputs a detection signal corresponding thereto. The electrical control device 49 is a device including a microcomputer. The electrical control device 49 inputs detection signals from a plurality of sensors including the sensor 48 and drives the control valve 46 by executing a program stored in advance in a storage device. The control device 47 provides a means for adjusting the opening of the adjustment valve 46 to a restricted state during the warm-up period. The control device 47 also provides means for adjusting the opening degree of the adjustment valve 46 to a release state larger than the limit state when the temperature or pressure of the intermediate medium reaches the first control value TH1 during the warm-up period. The first control value TH1 is also called a utilization medium control value for controlling the utilization medium. Further, the control device 47 also provides means for adjusting the opening degree of the adjustment valve 46 to the released state after the warm-up period.

  FIG. 2 is a flowchart showing the operation of the electrical control device 49. The electric control device 49 repeatedly executes the flowchart at a predetermined cycle while the power switch such as the ignition switch of the vehicle is in the on state. As a result, the electrical control device 49 provides standby operation, warm-up operation, protection operation, and load operation.

  In step 101, the detection signal of the sensor 48 is input. In step 101, it is determined whether or not exhaust heat recovery by the waste heat recovery device 4 is necessary. For example, when there is a request from the heat utilization device 3, it is determined that there is a collection request when the cooling water temperature is a predetermined value or less. If there is no collection request, the process proceeds to step 103. In step 103, standby operation is performed. In the standby operation, the control valve 46 is maintained in a minute opening state. Even when exhaust heat is not recovered, high temperature exhaust gas flows through the evaporation section 41. In order to avoid the waste heat recovery unit 40 from reaching an excessively high temperature, a predetermined amount of cooling water is caused to flow according to the minute opening state in the standby operation.

  If it is determined in step 102 that there is a collection request, the process proceeds to step 104. In step 104, it is determined whether or not the engine 2 is warming up after being started. For example, any of the conditions such as when the engine 2 is within a predetermined time from the start, when the cooling water temperature is lower than a predetermined temperature, or when the pressure of the intermediate medium of the waste heat recovery unit 40 is lower than a predetermined value When at least one is established, it is determined that the engine is warming up. If it is not during the warm-up period, that is, after the warm-up is completed, the flowchart branches to step 105. In step 105, load operation is performed. In the load operation, the opening degree of the adjustment valve 46 is adjusted to the release state. This release state is a large opening range including full opening. In the load operation, the opening degree of the adjustment valve 46 is adjusted to an opening degree corresponding to a load such as a heat consumption amount by the heat utilization device 3. For example, according to the coolant temperature at the outlet of the heat utilization device 3, the amount of recovered heat can be increased by increasing the opening of the control valve 46 as the temperature decreases.

  If it is determined in step 104 that the engine is warming up, the process proceeds to step 106. In step 106, it is determined whether or not the pressure PR of the intermediate medium in the waste heat recovery unit 40 is greater than the lower limit value TH0. The lower limit value TH0 is provided in order to shorten the time required for warming up the waste heat recovery unit 40. If the pressure PR is less than or equal to the lower limit value TH0, the process proceeds to step 103. Since it can be evaluated that the pressure PR of the intermediate medium is too low, the same minute opening as in the standby operation is provided. Therefore, the flow rate of the cooling water supplied to the waste heat recovery unit 40, in other words, the heat taken out from the waste heat recovery unit 40 is limited. As a result, the amount of heat necessary for heating the waste heat recovery device 40 with the exhaust gas and warming it up is suppressed.

  If it is determined in step 106 that the pressure PR is greater than the lower limit value TH0, the routine proceeds to step 107. In step 107, it is determined whether or not the pressure PR is smaller than a first control value TH1 as an upper limit value. When the pressure PR is smaller than the first control value TH1, the process proceeds to step 108. In step 108, warm-up operation is performed. In the warm-up operation, the control valve 46 is adjusted to the limit opening. The limit opening is a small opening range that does not include full opening. Furthermore, in this warm-up operation, the opening of the control valve is adjusted so as to gradually increase as the warm-up progresses from the start of the warm-up operation. In the warm-up operation, the opening degree of the control valve 46 is increased as the pressure PR increases. However, the range is limited to the small opening range.

  If it is determined in step 107 that the pressure PR is equal to or higher than the first control value TH1, the process proceeds to step 109. In step 109, the protection operation is performed. In the protective operation, the control valve 46 is kept fully open. When the control valve 46 is fully opened, the maximum cooling water that can flow at that time flows into the condensing unit 42 and the maximum condensing capacity is exhibited. As a result, even if the pressure PR of the intermediate medium is excessively increased, the condensing capacity is increased, so that it is possible to avoid the excessive increase of the pressure PR. The first control value TH1 is provided in order to avoid an excessive increase in the pressure of the intermediate medium in the waste heat recovery unit 40. In addition, when the temperature of the cooling water is high or the cooling water flow rate is small, the excessive increase in the pressure PR may not be suppressed only by fully opening the control valve. In this case, the pressure PR may exceed the first control value TH1 and reach the second control value TH2. In such a case, the circulation restriction valve 45 provided in the waste heat recovery device 40 is closed, so that the evaporation of the intermediate medium is restricted and an excessive increase in the pressure PR is avoided. In order to provide such stepwise protection operation, the first control value TH1 is set to a temperature or pressure lower than the second control value TH2.

  FIGS. 3A, 3 </ b> B, and 3 </ b> C are graphs showing state changes when the control valve 46 is kept fully open after the engine 2 is started. 4 (A), 4 (B), 4 (C), and 4 (D) are graphs showing state changes when the control valve 46 is controlled according to this embodiment after the engine 2 is started. It is. The solid line in FIG. 4 shows the case where the exhaust gas temperature rises slowly. The dashed-dotted line in FIG. 4 shows a case where the exhaust gas temperature suddenly rises due to an increase in the amount of fuel supply. Q indicates the increase or decrease in the amount of heat seen from the cooling water system. DV indicates the opening degree of the control valve 46. TE indicates the temperature of the exhaust gas. PR indicates the pressure of the intermediate medium in the waste heat recovery unit 40.

  FIG. 3 shows a case where the engine 2 is started at time t0 from a state where the engine 2 is cooled to room temperature. When the engine 2 is started, the exhaust gas temperature TE rises. In such a transient state, the exhaust gas temperature TE rises rapidly, but the temperature of the equipment belonging to the exhaust system 22 rises with a delay. Such a delay is caused by the heat capacities of the exhaust pipes and the catalyst 24 constituting the exhaust system 22 and the heat capacity of the waste heat recovery unit 40 itself. Therefore, a delay time occurs in order for the waste heat recovery device 40 to recover the heat of the exhaust gas. Furthermore, due to these heat capacities, immediately after the engine 2 is started, the waste heat recovery unit 40 takes heat of the cooling water. For example, the amount of heat is taken from the cooling water system until time tc. Further, coupled with heat radiation to the atmosphere in the cooling water system that occurs at the same time, the rise in the cooling water temperature is delayed.

  FIG. 4 shows a case where the engine 2 is started at time t0 from a state where the engine 2 is cooled to room temperature. When the engine 2 is started, the exhaust gas temperature TE rises. As the exhaust gas temperature TE rises, the pressure PR of the intermediate medium rises. While the pressure PR is lower than the lower limit value TH0, the opening degree DV of the control valve 46 is maintained at a minute opening degree.

  Thereafter, when the pressure PR becomes higher than the lower limit value TH0 at time t1, the warm-up operation is started. During the warm-up operation, the opening degree DV of the control valve 46 is set in direct proportion to the pressure PR. Therefore, as the pressure PR increases, the opening degree DV increases. However, the increase range of the opening degree DV is limited to the small opening degree range. This small opening range is set to a range equal to or less than the half opening of the control valve 46. During the warm-up operation, the opening degree of the control valve 46 increases as the warm-up progresses, so that an excessive increase in the pressure of the intermediate medium is avoided. Immediately after the engine 2 is started, the exhaust gas temperature TE may increase rapidly. Control for gradually increasing the opening degree DV of the control valve 46 is effective for avoiding an excessive increase in the pressure of the intermediate medium even if the exhaust gas temperature TE suddenly increases. The warm-up operation is continued until the warm-up period is completed. For example, the warm-up operation is continued until the pressure PR reaches the first control value TH1. In this embodiment, the warm-up period is from time t0 to time t2 or from time t0 to time t3. Therefore, the standby operation in step 103 and the warm-up operation in step 108 mean the warm-up operation in a broad sense.

  When the exhaust gas temperature TE further increases, the pressure PR reaches the first control value TH1. When the pressure PR becomes equal to or higher than the first control value TH1, the protective operation is started. When the pressure PR becomes equal to or higher than the first control value TH1 at time t2 or time t3, the opening degree DV of the control valve 46 is adjusted to full open. Therefore, the opening degree DV of the control valve 46 increases rapidly. As a result, a large amount of cooling water is supplied to the condensing unit 42, the condensation of the intermediate medium is promoted, and the increase in the pressure PR is suppressed.

  When the exhaust gas temperature TE further increases, the pressure PR may reach the second control value TH2. When the pressure PR reaches the second control value TH2 at time t4, the circulation restriction valve 45 closes the liquid passage 44. Accordingly, the circulation of the intermediate medium in the waste heat recovery unit 40 is interrupted, and the heat transport is stopped. As a result, the evaporation of the intermediate medium is limited, the increase in the pressure PR is suppressed, and the temperature rise in the cooling water is also suppressed. The circulation restriction valve 45 opens again when the pressure PR of the intermediate medium returns to the normal range, and resumes heat transport.

  In this embodiment, during the warm-up period, the opening degree of the control valve 46 is adjusted to the restricted state, so that it is possible to suppress the amount of heat taken out from the cooling water system 23. Further, when the temperature or pressure of the intermediate medium reaches the first control value TH1 during the warm-up period, the opening degree of the adjustment valve 46 is adjusted to a release state larger than the limit state. For this reason, it can be avoided that the intermediate medium reaches an abnormal state such as excessively high temperature or excessively high pressure.

  In addition, since a circulation type heat pipe including the circulation restriction valve 45 is adopted as the waste heat recovery device 40, the intermediate medium is prevented from reaching an excessively high temperature and an excessively high pressure even by the second control value TH2. The Furthermore, since the first control value TH1 is at a lower temperature or lower pressure than the second control value TH2, multiple protections can be provided.

  Further, since the control device 47 gradually increases the opening of the control valve as the warm-up progresses, it is possible to avoid excessive heat accumulation in the intermediate medium. Moreover, since the small opening range which does not include a full open is employ | adopted as a restriction | limiting state, warming-up can be accelerated. On the other hand, since a large opening range including full open is employed as the release state, abnormal states such as excessive high temperature and excessive high pressure of the intermediate medium can be avoided with high probability. Furthermore, since the opening degree of the control valve is adjusted to the released state after the warm-up period, the heat of the exhaust gas can be sufficiently recovered after the warm-up is completed.

(Other embodiments)
The present invention is not limited to the above-described embodiments, and can be modified or expanded as follows without departing from the spirit of the present invention.

  For example, the control device 47 may be configured to detect the temperature of the intermediate medium and adjust the opening of the control valve instead of the pressure of the intermediate medium. Further, instead of the sensor 48 and the electrical control device 49 constituting the control device 47, a temperature-displacement converter such as a thermostat or a pressure-displacement converter such as a diaphragm can be used to drive the control valve. it can.

  The opening of the adjustment valve in each operating state can be adjusted as follows instead of the above embodiment. In the standby operation, the control valve may be adjusted to a fully closed state. In the warm-up operation, the control valve may be fixed at a small opening that is slightly larger than the fully closed state and smaller than the middle opening. Further, in the warm-up operation, the opening degree of the control valve may be gradually increased as time elapses. In the protective operation, the control valve may have a large opening that is slightly smaller than the full opening and larger than the middle opening. In the load operation, the control valve may be fully opened or fixed at a large opening. Furthermore, also in the load operation, the same determination as that in step 106 may be performed to shift to the protection operation.

  The waste heat recovery unit 40 can use a heat pipe in which the steam passage and the liquid passage are combined into one passage instead of the circulation heat pipe. The usage system 23 can be a system in which hot water circulated independently of the cooling water of the engine 2 instead of the system in which the cooling water of the engine 2 circulates. Moreover, the utilization medium of the utilization system | strain 23 can be made into the fluid for lubricating or operating a vehicle equipment instead of cooling water. For example, the utilization medium may be engine oil for lubricating the engine 2, transmission oil used for lubricating and operating a vehicle transmission, or differential oil for lubricating a differential gear.

The waste heat recovery device 4 can be applied to a stationary internal combustion engine instead of the in-vehicle device 1. For example, the waste heat recovery device 4 may be combined with a cogeneration device that uses an internal combustion engine as a power source and a heat source. As the heat source, an external combustion engine or the like can be used instead of the engine 2.

FIG. 1 is a block diagram showing a configuration of an in-vehicle device 1 according to an embodiment to which the present invention is applied. FIG. 2 is a flowchart illustrating the operation of the control device according to the embodiment. FIG. 3 is a graph showing a change in state when the opening of the control valve is fixed fully open. FIG. 3 (A) is a graph showing the amount of heat of the cooling water system, and FIG. 3 (B) is an open state of the control valve. FIG. 3C is a graph showing the exhaust gas temperature. 4A and 4B are graphs showing state changes according to the embodiment, in which FIG. 4A is a graph showing the amount of heat of the cooling water system, FIG. 4B is a graph showing the opening of the control valve, and FIG. ) Is a graph showing the exhaust gas temperature, and FIG. 4D is a graph showing the pressure of the intermediate medium.

Explanation of symbols

2 Engine 21 Main Body 22 Exhaust System 23 Cooling Water System 3 Heat Utilization Device 4 Waste Heat Recovery Device 40 Waste Heat Recovery Device 41 Evaporator 42 Condenser 43 Steam Passage 44 Liquid Passage 45 Circulation Limit Valve 46 Control Valve 47 Control Device 48 Sensor 49 Electrical control device

Claims (8)

The exhaust system (22) through which the exhaust gas of the internal combustion engine or the external combustion engine (2) flows and the utilization system (23) through which the utilization medium flows are thermally connected via an intermediate medium, and the heat of the exhaust system is utilized in the above manner. waste heat recovery device that Ru incorporated system (40),
Control valve adjusts the opening degree of the passage of the available media, adjusting the flow rate of the available media to be supplied to the waste heat recovery unit (46),
During the warm-up period of the waste heat recovery device, the opening degree of the control valve is adjusted to a restricted state, and when the temperature or pressure of the intermediate medium reaches the utilization medium control value (TH1) during the warm-up period. And a control device (47) for adjusting the opening of the control valve to a release state larger than the limit state. The waste heat recovery unit (40)
An evaporation section provided in the exhaust system;
A condensing part provided in the utilization system;
A circulation passage including a steam passage and a liquid passage connecting the evaporation section and the condensation section;
A circulation type heat pipe provided with a circulation restriction valve (45) that is provided in the liquid passage and restricts the opening degree of the liquid passage when the temperature or pressure of the intermediate medium reaches an intermediate medium control value (TH2). The waste heat recovery apparatus according to claim 1.   The waste heat recovery apparatus according to claim 2, wherein the utilization medium control value is a temperature or a pressure lower than the intermediate medium control value. The waste according to any one of claims 1 to 3, wherein the control device gradually increases the opening of the control valve in the restricted state as the warm-up of the waste heat recovery device progresses. Heat recovery device.   The waste heat recovery apparatus according to any one of claims 1 to 4, wherein the restricted state is a small opening range that does not include full opening.   The waste heat recovery apparatus according to any one of claims 1 to 5, wherein the release state is a large opening range including full opening.   The waste heat recovery apparatus according to claim 6, wherein the control device further adjusts the opening of the control valve to the released state after the warm-up period. The controller is
A sensor (48) for detecting the temperature or pressure of the intermediate medium;
The waste heat recovery apparatus according to any one of claims 1 to 7, further comprising an electrical control device (49) for inputting a detection signal of the sensor and driving the control valve.

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