JP5780185B2 - Waste heat recovery device - Google Patents

Description

  The present invention relates to an exhaust heat recovery apparatus.

  Uses reversible chemical reactions such as adsorption and hydration of substances as an exhaust heat recovery device that recovers exhaust heat from exhaust heat means (exhaust heat source) such as cogeneration systems and effectively uses the recovered heat. There is a chemical heat pump using a chemical heat storage material that absorbs and releases heat (heat storage and heat dissipation) (see, for example, Patent Document 1).

  This exhaust heat recovery device reacts with a reaction medium to generate heat, absorbs heat and regenerates the reaction medium, converts the reaction medium from liquid to gas, and communicates with the reaction part. And an evaporation unit configured to be able to supply the reaction medium.

  In this exhaust heat recovery device, the reaction unit uses the exhaust heat recovered from the exhaust heat means to regenerate the reaction medium that has reacted with the chemical heat storage material (heat storage process), and the reaction medium supplied from the evaporation unit It reacts with chemical heat storage materials to release heat (heat dissipation process).

Japanese Patent Laying-Open No. 2005-230738

  By the way, when the exhaust heat recovery device is used to recover exhaust heat from the exhaust heat means and to return the heat to the exhaust heat means, the temperature of the returned heat is the temperature of the exhaust heat means. If it is far away from, the merit of refluxing heat is small. For this reason, in the use which recirculates heat to the exhaust heat means, there is a problem that the exhaust heat recovered from the exhaust heat means cannot be effectively used.

  The temperature of heat released from the chemical heat storage material (exothermic temperature) is determined by the pressure in the reaction unit, that is, the pressure corresponding to the evaporation temperature of the reaction medium in the evaporation unit communicating with the reaction unit. For this reason, when the reaction medium is evaporated in the evaporation section at room temperature, the temperature of the heat released from the chemical heat storage material becomes a temperature corresponding to the internal pressure of the evaporation section at this time. Usually, this temperature is far from the temperature of the exhaust heat means itself, and is inappropriate for the heat to be recirculated to the exhaust heat means.

  In view of the above points, an object of the present invention is to provide an exhaust heat recovery apparatus that can effectively use exhaust heat recovered from exhaust heat means.

In order to achieve the above object, in the invention described in claim 1,
A reaction section (2, 3) having a chemical heat storage material that generates heat by reacting with the reaction medium and absorbs heat to regenerate the reaction medium;
An evaporation section (4) configured to convert the reaction medium from a liquid to a gas and to be able to supply the reaction medium in communication with the reaction section;
The reaction unit regenerates the reaction medium that has reacted with the chemical heat storage material using the exhaust heat recovered from the heat exhaust means, and reacts the reaction medium supplied from the evaporation unit with the chemical heat storage material to generate heat associated with the reaction. Is configured to heat the heat medium and supply it to the exhaust heat means.
The evaporation unit is configured to heat the reaction medium using the exhaust heat recovered from the exhaust heat means to convert the reaction medium from liquid to gas, and the internal pressure of the evaporation unit uses the exhaust heat. Thus, the pressure is in accordance with the evaporation temperature of the heated reaction medium .

  Here, as described above, the temperature (exothermic temperature) of the heat released by the chemical heat storage material during the reaction with the reaction medium is equal to the pressure in the reaction part, that is, the evaporation temperature of the reaction medium in the evaporation part communicating with the reaction part. If the evaporation temperature of the reaction medium is high, the exothermic temperature of the chemical heat storage material is high, and if the evaporation temperature of the reaction medium is low, the exothermic temperature of the chemical heat storage material is low. The temperature of the exhaust heat is a temperature closer to the temperature of the exhaust heat means than the normal temperature.

  For this reason, according to the present invention, the reaction medium is evaporated in the evaporation section at a temperature closer to the temperature of the exhaust heat means than the normal temperature by using the exhaust heat recovered from the exhaust heat means. Compared with the case where the heat is performed at room temperature, the temperature of the heat recirculated to the heat exhausting means can be shifted to the temperature side of the heat exhausting means.

  As a result, according to the present invention, compared with the case where the reaction medium is evaporated at room temperature, heat at an appropriate temperature can be recirculated to the exhaust heat means, and the exhaust heat recovered from the exhaust heat means can be recovered. Effective use.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is the schematic which shows the whole structure of the waste heat recovery apparatus in 1st Embodiment of this invention. It is explanatory drawing for demonstrating the action | operation of the waste heat recovery apparatus of FIG. It is explanatory drawing for demonstrating the action | operation of the waste heat recovery apparatus of FIG. The measurement result of the CaBr 2 · _H 2 _O and water vapor pressure curve of the present invention we have determined.

(First embodiment)
As shown in FIG. 1, the exhaust heat recovery apparatus 1 of the present embodiment recovers exhaust heat from the factory furnace 100 and supplies heated air to the factory furnace 100.

  The factory furnace 100 is an energy conversion means that is supplied with fuel and oxidant as energy sources and converts energy by utilizing the oxidative heat generated by the fuel and oxidant, and also discharges heat that is discharged along with this energy conversion. It is a heat means. As the fuel, natural gas, city gas, heavy oil, kerosene and the like are used. Specifically, the factory furnace 100 converts the fuel into thermal energy of about 500 ° C. by combustion of fuel and air, and discharges combustion gas around about 155 ° C.

  The exhaust heat recovery apparatus 1 includes two reactors (first and second reactors 2 and 3) as reaction units, an evaporator 4 as an evaporation unit, and a condenser 5 as a condensing unit. .

  Although not shown, each of the first and second reactors 2 and 3 includes a chemical heat storage material, a heat exchanger filled with the chemical heat storage material, and a case for housing the heat exchanger.

The chemical heat storage material reacts with the reaction medium to generate heat and absorbs heat to regenerate the reaction medium. In this embodiment, CaBr ₂ that is an ionic crystal is used as the chemical heat storage material, and H ₂ O is used as the reaction medium. As shown in the following reaction formula (1), CaBr ₂ (solid) reacts (hydrates) with H ₂ O (gas) to generate heat (heat dissipation) and as shown in the following reaction formula (2). In addition, when CaBr ₂ · H ₂ O (solid) is in a hydrated state, it absorbs heat and regenerates (releases) H ₂ O (gas). CaBr ₂ is the temperature of the combustion gas discharged from the factory furnace 100 and can regenerate H ₂ O.

第１、第２反応器２、３は、どちらも、燃焼ガス入口側が、燃焼ガス流路を構成する燃焼ガス用配管１１を介して、工場炉１００の燃焼ガス出口側と接続されている。燃焼ガス用配管１１は、分岐点を有し、分岐点から第１反応器２に向かう流路と、分岐点から第２反応器３に向かう流路とを有している。燃焼ガス用配管１１の分岐点には３方弁１２が設けられている。この３方弁１２は、第１反応器２へ燃焼ガスを供給する状態（第１反応器２への燃焼ガス供給状態）と、第２反応器３へ燃焼ガスを供給する状態（第２反応器３への燃焼ガス供給状態）とを切り替える切替手段であり、特許請求の範囲に記載の第１切替手段に対応する。

In both the first and second reactors 2 and 3, the combustion gas inlet side is connected to the combustion gas outlet side of the factory furnace 100 via the combustion gas pipe 11 constituting the combustion gas flow path. The combustion gas pipe 11 has a branch point, and has a flow path from the branch point to the first reactor 2 and a flow path from the branch point to the second reactor 3. A three-way valve 12 is provided at a branch point of the combustion gas pipe 11. The three-way valve 12 is in a state in which combustion gas is supplied to the first reactor 2 (a combustion gas supply state in the first reactor 2) and in a state in which combustion gas is supplied to the second reactor 3 (second reaction). Switching means for switching the combustion gas supply state to the vessel 3 and corresponds to the first switching means described in the claims.

  In each of the first and second reactors 2 and 3, a combustion gas pipe 14 communicating with the combustion gas discharge port 13 is connected to the combustion gas outlet side.

  Further, the first and second reactors 2 and 3 are both connected to an air inlet 22 with an air pipe 21 constituting an air flow path connected to the air inlet. The air pipe 21 has a branch point, and has a flow path from the branch point to the first reactor 2 and a flow path from the branch point to the second reactor 3. A three-way valve 23 is provided at the branch point of the air pipe 21. The three-way valve 23 supplies air to the first reactor 2 (air supply state to the first reactor 2) and supplies air to the second reactor 3 (to the second reactor 3). Switching means for switching the air supply state). The three-way valve 23 switches between the case where air passes through the first reactor 2 and is supplied to the factory furnace 100 and the case where air passes through the second reactor 3 and is supplied to the factory furnace 100. It is done. The three-way valve 23 corresponds to the third switching means described in the claims.

  In both the first and second reactors 2 and 3, the air outlet side is connected to the air inlet side of the factory furnace 100 via an air pipe 24 that constitutes an air flow path. The air pipes 24 connected to the first and second reactors 2 and 3 are joined together and connected to the factory furnace 100, but the two air pipes 24 are directly connected to the factory furnace 100. It may be connected.

  When the air supplied to the factory furnace 100 passes through the heat exchanger, the heat exchanger included in the first and second reactors 2 and 3 exchanges heat between the air and the chemical heat storage material. When the discharged combustion gas passes through the heat exchanger, heat exchange is performed between the combustion gas and the chemical heat storage material. In the present embodiment, the temperature of the combustion gas when the heat exchange between the combustion gas and the chemical heat storage material is adjusted to 155 ° C. inside the heat exchangers of the first and second reactors 2 and 3. ing.

  The evaporator 4 converts the reaction medium from liquid to gas. The evaporator 4 is a heat exchanger that exchanges heat between the reaction medium and the combustion gas exhausted from the factory furnace 100, recovers exhaust heat from the factory furnace 100, and heats the reaction medium with the recovered exhaust heat. It is like that.

  The combustion gas inlet side of the evaporator 4 is connected to the combustion gas outlet side of the factory furnace 100 via a combustion gas pipe 15 constituting the combustion gas flow path. In FIG. 1, the combustion gas pipe 15 is branched from the combustion gas pipe 11, but may be directly connected to the combustion gas outlet side of the factory furnace 100. A combustion gas pipe 16 communicating with the combustion gas discharge port 13 is connected to the combustion gas outlet side of the evaporator 4.

  In the present embodiment, the temperature of the combustion gas when heat exchange with the reaction medium is adjusted to 100 ° C. inside the evaporator 4. For example, the heat exchange area of the evaporator 4 is adjusted, or the length of the combustion gas pipe 15 between the evaporator 4 and the factory furnace 100 is adjusted.

  The evaporator 4 communicates with each of the first and second reactors 2 and 3 and is configured to supply a reaction medium to the first and second reactors 2 and 3. Specifically, the evaporator 4 is connected to the first reactor 2 via a reaction medium pipe 31 constituting the first reaction medium flow path. The reaction medium pipe is provided with a first on-off valve 32. When the first on-off valve 32 is opened, the evaporator 4 is in communication with the first reactor 2, and the reaction to the first reactor 2 is performed. The medium can be supplied. Similarly, the evaporator 4 is connected to the second reactor 3 via a reaction medium pipe 33 constituting the second reaction medium flow path. The reaction medium pipe 33 is provided with a second opening / closing valve 34, and the opening of the second opening / closing valve 34 brings the evaporator 4 into communication with the second reactor 3, and the connection to the second reactor 3. The reaction medium can be supplied.

  When one of the first and second on-off valves 32 and 34 is opened and the other is closed, the communication state between the first reactor 2 and the evaporator 4 and the communication state between the second reactor 3 and the evaporator 4 are Is switched. Therefore, the first and second on-off valves 32 and 34 are described in the claims as “the communication state between one of the two reactors and the evaporation portion, the other of the two reactors and the evaporation portion. The 2nd switching means "which switches a communication state with is comprised.

  The condenser 5 converts the reaction medium from gas to liquid, and is a heat exchanger that cools and condenses the reaction medium by exchanging heat between the reaction medium and the outside air.

  The condenser 5 communicates with each of the first and second reactors 2 and 3 and is configured to receive the reaction medium regenerated in the first and second reactors 2 and 3. Specifically, the condenser 5 is connected to the first reactor 2 via a reaction medium pipe 35 constituting a third reaction medium flow path. The reaction medium pipe is provided with a third on-off valve 36. When the third on-off valve 36 is opened, the condenser 5 is in communication with the first reactor 2, and the reaction from the first reactor 2 is performed. Media can be accepted. Similarly, the condenser 5 is connected to the second reactor 3 via a reaction medium pipe 37 constituting the fourth reaction medium flow path. The reaction medium pipe is provided with a fourth on-off valve 38. When the fourth on-off valve 38 is opened, the condenser 5 communicates with the second reactor 3, and the reaction from the second reactor 3 is performed. Media can be accepted.

  When one of the third and fourth on-off valves 36 and 38 is opened and the other is closed, the communication state between the first reactor 2 and the condenser 5 and the communication state between the second reactor 3 and the condenser 5 are Is switched. Therefore, the third and fourth on-off valves 36 and 38 are described in the claims as "the communication state between one of the two reactors and the condensing unit, the other of the two reactors and the condensing unit" 4th switching means for switching between the communication state and the communication state ”.

  The evaporator 4 and the condenser 5 are connected by a reaction medium pipe 39 that constitutes a fifth reaction medium flow path. When the fifth on-off valve 40 provided in the reaction medium pipe 39 is opened, the reaction medium condensed in the condenser 5 is supplied to the evaporator 4.

  Further, the exhaust heat recovery apparatus 1 includes an electronic control device 50 as a control means. The electronic control unit 50 controls switching of the three-way valve 12 provided in the combustion gas pipe 11 and the three-way valve 23 provided in the air pipe 21, and the first on-off valve 32 and the second on-off valve. Control of opening / closing of the valve 34, the third on-off valve 36, the fourth on-off valve 38, and the fifth on-off valve 40 is controlled.

  Next, the operation of the exhaust heat recovery apparatus 1 configured as described above will be described with reference to FIGS.

  As shown in FIG. 2, the electronic control unit 50 controls the first and second on-off valves 32 and 34 to open the first on-off valve 32 and close the second on-off valve 34, thereby The vessel 2 and the evaporator 4 are connected. Further, the electronic control device 50 controls the three-way valve 23 provided in the air pipe 21 so that air passes through the first reactor 2 and is supplied to the factory furnace 100.

  Further, the electronic control unit 50 controls the third and fourth on-off valves 36 and 38 to close the third on-off valve 36 and open the fourth on-off valve 38, so that the second reactor 3 and the condenser are opened. Communicate with 5. Further, the electronic control unit 50 controls the three-way valve 12 provided in the combustion gas pipe so that the combustion gas is supplied to the second reactor 3.

In particular, the combustion gas is supplied to the evaporator 4 without controlling the valve. In the evaporator 4, H ₂ O (liquid) is heated at a temperature of 100 ° C.

Thus, in the first reactor 2, as shown in the reaction formula (1), reacted with between H _{2 O} and CaBr ₂ supplied from the evaporator 4, the plant furnace 100 by the heat due to the reaction A first function for heating the supplied air is performed.

At this time, since the first reactor 2 and the evaporator 4 are in communication with each other, the reaction formula (1) proceeds under a pressure corresponding to the internal pressure of the evaporator 4. In the present embodiment, the evaporator 4 is used in which the atmospheric pressure, which is industrially easy to design, is set as the upper limit of the internal pressure. Therefore, the evaporation temperature of H ₂ O in the evaporator 4 is set to 100 ° C. As shown in FIG. 4, the water vapor pressure at 100 ° C. is 101.3 kPa, and the temperature of CaBr ₂ · H ₂ O at the vapor pressure corresponding to this water vapor pressure is 246 ° C. It is the heat radiation temperature in (1). Therefore, the air supplied to the factory furnace can be preheated at 246 ° C.

On the other hand, in the second reactor 3, when combustion gas is supplied, heat input from the combustion gas is received, and H ₂ O reacted with CaBr ₂ is regenerated as shown in the reaction formula (2). The second function is executed. Furthermore, when the second reactor 3 communicates with the condenser 5, the regenerated H ₂ O flows into the condenser 5, and H ₂ O is converted from gas to liquid by the condenser 5.

At this time, since the second reactor 3 and the condenser 5 are in communication with each other, the reaction formula (2) and the condensation of H ₂ O proceed under the same pressure. In the present embodiment, as the reaction formula (2) proceeds at a temperature of 155 ° C., as shown in FIG. 4, when the 155 ° C., the vapor pressure of CaBr ₂ · _{H 2} O is 2.4 kPa, 20 Since the water vapor pressure is equivalent to ° C., the condenser 5 can condense H ₂ O at a temperature of 20 ° C.

The electronic control unit 50 opens the fifth on-off valve 40 to cause the H ₂ O condensed by the condenser 5 to flow into the evaporator 4.

  When the execution of the first function in the first reactor 2 and the execution of the second function in the second reactor 3 are completed, the electronic control unit 50 has two functions, the first function and the second function. The first, second, third and fourth on-off valves 32, 34, 36 and 38 are controlled so as to be switched in the reactor.

  Specifically, as shown in FIG. 3, the electronic control unit 50 controls the first and second on-off valves 32 and 34 to close the first on-off valve 32 and open the second on-off valve 34. Then, the second reactor 3 and the evaporator 4 are communicated. Further, the electronic control unit 50 controls the three-way valve 23 provided in the air pipe 21 so that air passes through the second reactor 3 and is supplied to the factory furnace 100.

  In addition, the electronic control unit 50 controls the third and fourth on-off valves 36 and 38 to open the third on-off valve 36 and close the fourth on-off valve 38, so that the first reactor 2 and the condenser are closed. Communicate with 5. Further, the electronic control unit 50 controls the three-way valve 12 provided in the combustion gas pipe so that the combustion gas is supplied to the first reactor 2.

Even at this time, the combustion gas is supplied to the evaporator 4, and H ₂ O (liquid) is heated at a temperature of 100 ° C. in the evaporator 4.

Thus, in the second reactor 3, as shown in the reaction formula (1), reacted with between H _{2 O} and CaBr ₂ supplied from the evaporator 4, the plant furnace 100 by the heat due to the reaction A first function for heating the supplied air is performed.

On the other hand, in the first reactor 2, when combustion gas is supplied, heat input from the combustion gas is received, and H ₂ O that has reacted with CaBr ₂ is regenerated as shown in the reaction formula (2). The second function is executed. Furthermore, when the first reactor 2 communicates with the condenser 5, the regenerated H ₂ O flows into the condenser 5, and H ₂ O is converted from gas to liquid by the condenser 5.

  As described above, the heat storage device 1 of the present embodiment constitutes a gas-solid absorption type chemical heat pump according to the above reaction formulas (1) and (2) that raise the exhaust heat at 155 ° C. to the high-temperature heat at 246 ° C. .

As described above, in the present embodiment, in one of the first and second reactors 2 and 3, the exhaust heat of the factory furnace 100 is recovered, and the recovered heat is used to react with CaBr ₂ in H ₂ O. In the other of the first and second reactors 2 and 3, H ₂ O supplied from the evaporator 4 and CaBr ₂ are reacted with each other, and air is heated by the heat associated with this reaction to produce a factory furnace. First and second reactors 2 and 3 are configured to supply to 100.

The evaporator 4 is heated of H _{2 O} by using exhaust heat discharged from the factory furnace 100 is configured of H 2 _O to convert from a liquid to a gas.

Here, the heat release temperature during the reaction of CaBr ₂ and H ₂ O is a temperature corresponding to the internal pressure of the first and second reactors 2 and 3. Since the first and second reactors 2 and 3 are in communication with the evaporator 4, the internal pressure of the first and second reactors 2 and 3 is the same as the internal pressure of the evaporator 4. For this reason, unlike the present embodiment, when the evaporation in the evaporator 4 is performed at room temperature, the heat dissipation temperature corresponds to the vapor pressure corresponding to the water vapor pressure at that temperature. For example, when the evaporation temperature in the evaporator 4 is 20 ° C. (room temperature), as shown in FIG. 4, the water vapor pressure at that time is 2.4 kPa, and CaBr ₂ · H at a vapor pressure corresponding to the pressure is obtained. _Since the temperature of ₂ O is 155, the heat release temperature during the reaction of CaBr ₂ and H ₂ O at a vapor pressure corresponding to the pressure is 155 ° C.

On the other hand, in this embodiment, since the evaporation temperature in the evaporator 4 is set to 100 ° C. using the exhaust heat discharged from the factory furnace 100, the reaction of CaBr ₂ and H ₂ O as described above. The heat release temperature at that time is 246 ° C.

As described above, according to this embodiment, the exhaust heat recovered from the factory furnace 100 is used to evaporate H ₂ O in the evaporator 4 at a temperature closer to the temperature of the factory furnace 100 (500 ° C.) than the normal temperature. Since it is performed at (100 ° C.), the temperature of the heat to be refluxed to the factory furnace 100 can be shifted to the temperature side of the factory furnace 100 as compared with the case where H ₂ O is evaporated at room temperature.

As a result, according to the present embodiment, heat at an appropriate temperature can be recirculated to the factory furnace 100 as compared with the case where evaporation of H ₂ O is performed at room temperature, and the exhaust gas recovered from the factory furnace 100 can be recovered. Heat can be used effectively.

In this embodiment, the evaporation temperature in the evaporator 4 is set to 100 ° C. However, if the temperature is within a temperature range in which exhaust heat can be used and is higher than room temperature, the evaporation temperature may be set to another temperature. good. For example, if an evaporator that can withstand a pressure higher than the water vapor pressure at 100 ° C. is used, the evaporation temperature can be higher than 100 ° C., and the heat generation temperature of CaBr ₂ can be higher than 246 ° C. . Further, by setting the evaporation temperature to a temperature between 100 ° C. and 20 ° C., it can be a temperature between the heat generation temperature of the CaBr ₂ 246 ° C. and 155 ° C..

In this embodiment, H ₂ O reacted with CaBr ₂ is regenerated at a temperature of 155 ° C. However, H ₂ O reacted with CaBr ₂ can be regenerated at a temperature other than 155 ° C.

In the present embodiment, in one of the first and second reactors 2 and 3, H ₂ O and CaBr supplied from the evaporator 4 are communicated with the evaporator 4 and supplied with air. ₁ and the first function of heating the air by the heat accompanying the reaction is performed, and the exhaust heat from the factory furnace 100 is supplied to the other of the first and second reactors 2 and 3. Thus, the electronic control device 50 is connected to the first, second, third and fourth on-off valves 32 so that the second function of regenerating H ₂ O that has reacted with CaBr ₂ is performed simultaneously with the first function. 34, 36, and 38 are controlled. Furthermore, the electronic control unit 50 performs the first, second, third, and second so that the first function and the second function are switched between one and the other of the first and second reactors 2 and 3. 4 The on-off valves 32, 34, 36, and 38 are controlled.

  As a result, the exhaust heat recovery apparatus 1 can be continuously operated, and the supply air to the factory furnace 100 can be preheated continuously.

(Other embodiments)
(1) In 1st Embodiment, although the heat medium at the time of recirculating | refluxing heat to the factory furnace 100 was made into the air supplied to the factory furnace 100, it can also be used as the fuel supplied to the factory furnace 100 instead of air. Good, both fuel and air.

  (2) In the first embodiment, the exhaust heat recovery apparatus 1 has the first and second reactors 2 and 3 as the reaction unit, but the number of reactors may be three or more. The number of reactors may be one. In the case of having at least two reactors as the reaction unit, the first function is implemented in one of the two reactors and the second function is implemented simultaneously in the other of the two reactors as in the first embodiment. At the same time, the first function and the second function are switched between one and the other of the two reactors. In the case where there is one reactor, the first function and the second function are switched and executed.

(3) In the first embodiment, the exhaust heat recovery apparatus 1 includes the condenser 5, and the regenerated reaction medium (H ₂ O) is condensed by the condenser 5 and returned to the evaporator 4. The condenser 4 may be omitted and the regenerated reaction medium may be discharged to the outside of the exhaust heat recovery apparatus 1. In this case, a configuration in which the evaporator 4 is supplemented with the reaction medium is employed.

  (4) Although the case where the energy conversion means is the factory furnace 100 has been described in the first embodiment, the exhaust heat recovery apparatus of the present invention can be applied to other energy conversion means. As an energy conversion means, an engine that is mounted on a vehicle or the like, which outputs mechanical energy by using oxidation heat generated by a fuel and an oxidizer, or a fuel cell or the like that outputs mechanical energy. Examples include those that output electrical energy by an electrochemical reaction with the agent.

  (5) In the first embodiment, the exhaust heat recovery apparatus of the present invention is applied to the factory furnace 100 that exhausts 155 ° C. combustion gas, that is, to the exhaust heat means (energy conversion means) that exhausts warm heat. Although applied, it is also possible to apply the exhaust heat recovery apparatus of the present invention to exhaust heat means (energy conversion means) for discharging cold heat.

  Examples of the exhaust heat means for discharging the cold heat include a refrigeration apparatus that generates cold heat of −100 ° C. and discharges the exhaust heat of −10 ° C. after using the cold heat. In this case, in the first embodiment, the factory furnace 100 is changed to this refrigeration apparatus, the combustion gas from the factory furnace 100 is changed to a heat medium that transmits exhaust heat of −10 ° C., and the first and second reactors The air supplied to 2 and 3 is changed to a heat medium. At this time, as the chemical heat storage material, a material that absorbs heat at the exhaust heat temperature (−10 ° C.) of the refrigeration apparatus to regenerate the reaction medium is employed.

  Here, the temperature (exothermic temperature) of the heat released by the chemical heat storage material during the reaction with the reaction medium depends on the evaporation temperature of the reaction medium in the evaporator 4 communicating with the first and second reactors 2 and 3. As shown in FIG. 4, if the evaporation temperature of the reaction medium is high, the exothermic temperature of the chemical heat storage material is high, and if the evaporation temperature of the reaction medium is low, the exothermic temperature of the chemical heat storage material is low.

  Also in this case, the reaction medium is evaporated in the evaporator 4 at a temperature closer to the temperature of the refrigeration apparatus (−100 ° C.) than the normal temperature by utilizing the exhaust heat of −10 ° C., and thus the reaction medium is evaporated. Compared with the case where it is performed at normal temperature, the temperature of the cold heat returned to the refrigeration apparatus can be shifted to the temperature side of the refrigeration apparatus.

  As a result, even in this case, compared with the case where the reaction medium is evaporated at room temperature, heat at an appropriate temperature can be recirculated to the refrigeration apparatus, and the exhaust heat (cold heat) recovered from the refrigeration apparatus can be reduced. Effective use.

(6) Although H ₂ O is employed as the reaction medium in the first embodiment, NH ₃ may be employed instead of H ₂ O. This is because NH ₃ exhibits a hydrogen bond similarly to H ₂ O, and a reaction similar to the above reaction formula occurs.

  Moreover, in 1st Embodiment, although the ion crystal substance which combined Ca ion and Br ion was employ | adopted as a chemical heat storage material, you may employ | adopt another ion crystal substance. However, an ionic crystal obtained by combining at least one of Ca, Mg, Sr, and Ba cations belonging to alkaline earth and at least one of O, F, Cl, Br, and I anions. It is preferable to adopt. This is because a reversible reaction similar to CaBr2 occurs.

  Moreover, you may employ | adopt other chemical heat storage materials, such as a zeolite, not only the above-mentioned ionic crystal substance. The water adsorption reaction of zeolite also corresponds to the reaction described in the claims. The chemical heat storage material used in the exhaust heat recovery apparatus of the present invention may be a chemical heat storage material having vapor pressure characteristics as shown in FIG. In other words, any temperature can be used as long as the temperature at which the reaction medium is evaporated can be shifted from room temperature to shift the temperature at which the reaction medium is regenerated from the temperature at which the reaction medium is evaporated at room temperature.

1 Waste heat recovery device 2 1st reactor (reaction part)
3 Second reactor (reaction unit)
4 Evaporator (evaporator)
5 Condenser (condenser)
12 Three-way valve provided in combustion gas piping (first switching means)
23 Three-way valve provided in the air piping (third switching means)
32 1st on-off valve (2nd switching means)
34 Second on-off valve (second switching means)
36 3rd on-off valve (4th switching means)
38 4th on-off valve (4th switching means)
50 Electronic control device (control means)
100 Factory furnace (heat exhaust means)

Claims (5)

In the exhaust heat recovery device (1) for recovering exhaust heat from the exhaust heat means (100) for exhausting heat and heating the heat medium to supply to the exhaust heat means,
A reaction part (2, 3) having a chemical heat storage material that reacts with the reaction medium to generate heat and absorbs heat to regenerate the reaction medium;
An evaporation section (4) configured to convert the reaction medium from a liquid to a gas and to be able to supply the reaction medium in communication with the reaction section;
The reaction unit regenerates the reaction medium that has reacted to the chemical heat storage material using the exhaust heat recovered from the heat exhaust means, and the reaction medium supplied from the evaporation unit and the chemical heat storage material It is configured to react and heat the heat medium by heat accompanying the reaction and supply it to the exhaust heat means,
The evaporation unit is configured to heat the reaction medium using the exhaust heat recovered from the exhaust heat means to convert the reaction medium from liquid to gas, and the internal pressure of the evaporation unit is The exhaust heat recovery apparatus is characterized in that the pressure is in accordance with the evaporation temperature of the reaction medium heated using the exhaust heat. At least two reactors (2, 3) as the reaction section;
A first switching means (12) for switching between an exhaust heat supply state to one of the two reactors and an exhaust heat supply state to the other of the two reactors;
Second switching means (32, 34) for switching between a communication state between one of the two reactors and the evaporation unit and a communication state between the other of the two reactors and the evaporation unit;
A third switching means (23) for switching between a heat medium supply state to one of the two reactors and a heat medium supply state to the other of the two reactors;
In one of the two reactors, the reaction medium communicated with the evaporation section and the heat medium is supplied to react the reaction medium supplied from the evaporation section with the chemical heat storage material. The first function of heating the heat medium with the heat accompanying the heat is performed, and in the other of the two reactors, the exhaust heat from the exhaust heat means is supplied to react with the chemical heat storage material. Control means (50) for controlling the first, second and third switching means so that a second function for regenerating the reaction medium is performed simultaneously with the first function;
The control means controls the first, second, and third switching means so that the first function and the second function are switched between one and the other of the two reactors. The exhaust heat recovery apparatus according to claim 1. A condensing part (5) configured to communicate with the reaction part and to accept the regenerated reaction medium, and to convert the regenerated reaction medium from gas to liquid;
Fourth switching means (36, 38) for switching between a communication state between one of the two reactors and the condensing unit and a communication state between the other of the two reactors and the condensing unit. Prepared,
When the second function is performed in the other of the two reactors, the control means communicates with the condensing unit to thereby regenerate the regenerated reaction medium from a gas in the condensing unit. Controlling the fourth switching means to convert to
The control means controls the first, second, third, and fourth switching means so that the first function and the second function are switched between two reactors. The exhaust heat recovery apparatus according to claim 2. The reaction medium is H ₂ O or NH ₃ ;
The chemical heat storage material is an ionic crystal that combines at least one of cation of Ca, Mg, Sr and Ba and at least one of anions of O, F, Cl, Br and I. The exhaust heat recovery apparatus according to any one of claims 1 to 3, wherein The exhaust heat means is supplied with a fuel and an oxidant as an energy source, and performs energy conversion using oxidation heat generated by the fuel and the oxidant.
The exhaust heat recovery apparatus according to any one of claims 1 to 4, wherein the heat medium is at least one of the fuel and the oxidant.

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