JPS61128071A - Heat accumulator for chemical heat pump - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat storage device for a chemical heat pump, and more specifically, an endothermic reaction in which isopropanol, a type of alcohol, is used as a reactant to decompose it into acetone and hydrogen. , the opposite exothermic reaction is combined, and the intermediate temperature of 50~
This relates to a chemical heat pump heat storage device that can obtain an easily available high heat source of 150 to 200 degrees Celsius from a low heat source of 120 degrees Celsius, and can use this high heat source for a wide range of purposes such as steam power generation and steam heating. be.

Conventional technology Chemical heat pumps using isopropanol as a reactant are described in Mainichi Shimbun, April 23, 1982.
It is described in the Nikkei Sangyo Shimbun dated June 6, 1982, the Journal of the Chemical Society of Japan published June 10, 1980, etc. That is,
A conventional chemical heat pump of this type has a configuration as shown in FIG.

In FIG. 2, 71 is a shell-and-tube heat exchanger type dehydrogenation reactor that decomposes liquid isopropanol into gaseous acetone and hydrogen using waste heat at about 80°C as a heat source; The generated gaseous substance is cooled in an upper shell-and-tube heat exchanger type dephlegmator 75, and the gaseous acetone and gaseous isopropanol accompanying the hydrogen are condensed and separated. A tray-type distillation column 74 is a shell-and-tube type in which unreacted gas of acetone and hydrogen from the distillation column 72 is introduced, heat is generated by a hydrogenation reaction at about 200° C., and the reaction product gas is returned to gaseous isopropanol. A heat exchanger type hydrogenation reactor, 75 indicates the distillation column 72 and the hydrogenation reactor 7.
The hydrogenation reactor 74 is provided between the distillation column 72 and the hydrogenation reactor 74.
Gaseous acetone and hydrogen flowing into the hydrogenation reactor 74
76 is an indirect contact type heat exchanger that heats and raises the temperature of the isopropanol gas flowing from the isopropanol gas to the distillation column 72 and the unreacted acetone and hydrogen gas;
This blower is provided between the distillation column 72 and returns the isopropanol gas, which has lost part of its heat in the heat exchanger 75, and the unreacted acetone and hydrogen gases to the distillation column 72.

To explain further, heat source fluids such as hot water and steam heated to approximately 80℃ due to factory waste heat, geothermal heat, solar heat, etc.
The waste heat fluid enters the dehydrogenation reactor 71 from the waste heat fluid supply pipe 77 , heats the liquid isopropanol inside, and supplies the waste heat fluid to the waste heat fluid discharge pipe 7 .
It is discharged from 8. Meanwhile, about 80°C in the dehydrogenation reactor 71
A part of the liquid isopropanol (the boiling point of isopropanol is 82.4°C at atmospheric pressure) heated at is decomposed into hydrogen (the boiling point of hydrogen is -252, 7°C at atmospheric pressure), becomes a gas-liquid mixed fluid, and is introduced into the distillation column 72 through piping 79, whereupon the gas rises and enters the dephlegmator 73. However, at this time, gaseous acetone and hydrogen are accompanied by gaseous isopropanol, so in the partial condenser 75.

The isopropanol is cooled to about 45° C. by the cooling water flowing in from the cooling water supply pipe 81 and flowing out from the cooling water discharge pipe 82, and the isopropanol is condensed and separated from gaseous acetone and hydrogen, reaching the bottom of the distillation column 72. The acetone and hydrogen are returned to the dehydrogenation reactor 71 through the liquid circulation pipe 80 along with the catalyst, but the acetone and hydrogen remain in gaseous state through the first unreacted gas line 83 and are heated to approximately 180°C in the heat exchanger 75. The unreacted gas is heated and introduced into the hydrogenation reactor 74 through a second line 84 .

In this hydrogenation reactor 74, gaseous acetone and hydrogen react in the presence of a nickel particulate catalyst.
It generates heat due to the hydrogenation reaction at ℃ and returns to gaseous isopropanol as a reaction product gas. This gaseous isopropanol at about 200°C, unreacted acetone gas, and hydrogen gas pass through the reaction product gas first line 85 and reach the heat exchanger 75, and the temperature is maintained at about 75°C without losing part of the heat. The reaction product gas is then returned to the distillation column 72 via the blower 76 in the second reaction product line 86, and the isopropanol is condensed in the distillation column 72. In addition, boiler water and the like is supplied from the first water supply pipe 87 to the steam drum 88, further passes through the second water supply pipe 89, and is heated in the hydrogenation reactor 74 to become a steam/water mixed flow.
Steam pipe 90 leads to a steam drum 88, where steam and water are separated and sent from a second steam pipe 91 to a predetermined device.

In the above description, the temperature of the waste heat (the temperature inside the dehydrogenation reactor 71) is about 80° C., but the temperature is not limited to this. In other words, the conventional technology described above utilizes the difference in boiling points between isopropanol and acetone, and since the boiling point changes depending on the pressure, if the pressure inside the reaction system is changed, the temperature of the waste heat can be raised to higher than 80°C. It can be low or low. Now, if the pressure of the reaction system is atmospheric pressure, the temperature of the waste heat is limited to about 80℃, but if the temperature of the waste heat is 50 to 1
When the temperature is 20°C, the pressure of the reaction system is correspondingly increased from 0.5 to 10 kg4. (absolute pressure).

Further, the upper limit of the temperature of the reactor 74 on the high-heat side is 202° C. if the pressure is atmospheric pressure, so the temperature may be lower than this, and if the pressure is increased, the temperature will rise.

Problems to be Solved by the Invention As mentioned above, conventional chemical heat pumps do not have a heat storage device, so if there are fluctuations in the waste heat source on the waste heat side or fluctuations in the load on the heat usage side, There is an excess or deficiency of gaseous acetone and hydrogen, which are unreacted substances, and gaseous isopropanol, which is a reaction product, and the balance between supply and demand is disrupted. There is a problem in that people have to refrain from using it.

In order to solve these problems, the present invention stores heat when there is excess heat from the waste heat source, and releases the stored heat when there is insufficient heat. The object of the present invention is to provide a heat storage device for a chemical heat pump that can utilize heat.

Means for solving the problem: A condenser that cools the gaseous acetone and hydrogen from the distillation column and condenses the acetone to separate it from the hydrogen, and a separation column that vaporizes the liquid acetone from the condenser. A hydrogen gas holder was installed for hydrogen, an acetone liquid storage tank was installed for acetone, and an isopropanol liquid storage tank was installed for isopropanol. In other words, the present invention has a structure in which, in a chemical heat pump using isopropanol as a reactant, there is a condenser that introduces acetone and hydrogen from a distillation column and condenses the acetone, and a condenser that condenses the acetone. a hydrogen gas line for supplying to the low-temperature side inlet of the reactor, and a separation column that introduces liquid acetone from the condenser and heats and vaporizes it with reaction products and unreacted substances from the high-temperature side of the heat exchanger. and a blower for supplying gaseous acetone and unreacted substances vaporized in the separation column to the low-temperature side inlet of the heat exchanger.

A pump that supplies a part of the liquid acetone condensed in the condenser to the inner upper part of the distillation column and another part to the inner upper part of the separation column, and a pump that supplies the isopropanol condensed in the separation column. and a pump for supplying the distillation column,
and a hydrogen gas holder that temporarily stores and stores hydrogen gas between the hydrogen gas line and the acetone line that supplies liquid acetone to the separation column. An isopropanol liquid storage tank in which liquid acetone is temporarily stored and discharged between an acetone liquid storage tank that stores and flows out liquid acetone and a liquid return line that supplies condensed isopropanol from the separation column to the distillation column. It is characterized by having the following.

Operation Gaseous acetone and hydrogen from the distillation column are introduced into a condenser where the acetone is condensed and separated from the hydrogen, and the separated hydrogen is fed to the cold side inlet of the heat exchanger.

On the other hand, acetone condensed in the condenser is sent to a separation column, heated by reaction products and unreacted substances from the high temperature side of the heat exchanger, vaporized, and supplied to the low temperature side inlet of the heat exchanger. be done. Ingropanol condensed in the separation column is returned to the distillation column in a liquid state. Therefore, in the dehydrogenation reactor, the hydrogenation reactor, and the heat exchanger, predetermined reactions and steps are carried out in the conventional manner.

In addition, if there is a change in the waste heat side or the heat use side, each substance is stored or released separately in the hydrogen gas holder, acetone liquid storage tank, and isopropanol liquid storage tank depending on the excess or deficiency. Therefore, rational utilization of waste heat is always achieved.

Embodiment FIG. 1 shows an embodiment of the present invention, in which 1 is a dehydrogenation reactor, 2 is a distillation column, 3 is a heat exchanger, and 4 is a dehydrogenation reactor.
is a hydrogenation reactor, 5 is a steam drum, 6 is a waste heat fluid supply pipe, 7 is a waste heat fluid discharge pipe, 8 is piping, 9 is a liquid circulation pipe,
10 is a first water supply pipe, 11 is a second water supply pipe, 12 is a first steam pipe, and 15 is a second steam pipe, which are basically the same as shown in FIG. 2 up to this point.

14 is a shell-and-tube heat exchanger type condenser that is installed on the dehydrogenation reaction side and introduces gaseous acetone and hydrogen from the distillation column 2 to condense the acetone and separate it from the hydrogen; 15; 16 is a cooling water supply pipe to the condenser 14, 16 is a cooling water discharge pipe thereof, 17 is a flow rate adjustment valve provided in the cooling water discharge pipe 16, and 18 is a pipe for supplying hydrogen from the condenser 14 to a heat exchanger 3. 19 is a condensate storage tank, 20 is this tank 19
A condensate line 21 connecting the condenser 14 to the hydrogenation reaction side introduces liquid acetone from the condensate storage tank 19 to the reaction product from the high temperature side outlet of the heat exchanger 3. and a separation column 22 for heating and vaporizing unreacted substances;
The line 25 is the acetone liquid first line 22 and the distillation column 2.
24 is a third acetone liquid line that connects the first acetone liquid line 22 with the upper part of the separation column 21, and 25 is provided in the first acetone liquid line 22. A pump, 26 is a flow rate regulating valve provided in the second line 23 of the acetone liquid, 27 is a flow rate regulating valve provided in the third line 24 of the acetone liquid, and 28 is a shell-and-tube heat exchanger type cooling device to be described later. vessel.

29 is a cooling water supply pipe to the cooler 28, 30 is a cooling water discharge pipe thereof, 61 is a reboin of a shell-and-tube heat exchanger type described later, and 52 is a connection between the top of the separation column 21 and the hydrogen gas line 18. An acetone gas line 33 is a blower installed on the acetone gas line 32.

34 is a first reaction product gas connected to the hydrogenation reactor 4.
line, 35 is a second reaction product gas line connecting this line 34 and the high temperature side inlet of the heat exchanger 3, 36 is a third reaction product gas line connecting this line 34 and the ribo-in 31, and 37 is the cooling A fourth reaction product gas line 38 connects the reactor 2B and the high temperature side outlet of the heat exchanger 5, a fifth reaction product gas line 38 connects the ribo-in 31 and the middle of the fourth reaction product gas line 67; A flow rate regulating valve 40 provided in the reaction product gas fifth line 38 is connected to the separation column 21.
A liquid return line that supplies the condensed liquid from the bottom to the center of the distillation column 2, 41 is a pump provided in the liquid return line 40, and 42 is a flow rate adjustment valve provided in the liquid return line 40. , 45 is a flow rate regulating valve provided in the waste heat fluid discharge pipe 7, 44 is a pressure controller that detects the pressure of the distillation column 2 and controls the valve 43, and 45 is the hydrogen gas line 1.
8, a temperature controller that detects the gas temperature and controls the valve 17; 46, an unreacted gas line connecting the hydrogenation reactor 4 and the low temperature side outlet of the heat exchanger 3; 47, the unreacted gas A flow rate adjustment valve provided in the line 46, 48 a pressure controller that detects the pressure of the steam drum 5 and controls the valve 47, 49 a flow rate adjustment valve provided in the first water supply pipe 10,
50 detects the liquid level of the steam drum 5 and closes the valve 49.
51 is a flow rate controller that detects the flow rate of the liquid return line 40 and inputs a detection signal from a detector 52 that detects the liquid level of the distillation column 2 to control the valve 42. , 53 is a flow rate controller that detects the flow rate of the acetone liquid fifth lie/24 and controls the valve 27, and 54 is a liquid level controller that detects the liquid level of the separation column 21 and controls the valve 59. , 55 is a liquid level controller that detects the liquid level of the condensate storage tank 19 and controls the valve 26, 56 is a hydrogen gas holder, and 5-'7 is provided as a branch from the hydrogen gas line 18. a hydrogen gas storage line connected to the holder 56; 58 is a compressor provided in the line 57;
59 is an on-off valve provided on the line 57; 60 is a hydrogen gas extraction line connecting the hydrogen gas storage line 57 and the hydrogen gas line 18 between the holder 56 and the valve 59;
1 is an acetone liquid storage tank; 62 is an acetone liquid storage line that is branched from the third acetone liquid line 24 and connected to the tank 61;

63 is an on-off valve provided in the line 62; 64 is an acetone liquid extraction line connecting the tank 61 and the line 24; 65 is a pump provided in the line 64; 66;
67 is an isopropanol liquid storage tank, 67 is an innopropanol liquid storage line that is branched from the discharge side of the pump 41 of the liquid return line 40 and connected to the tank 66, and 68 is an innopropanol liquid storage line that is connected to the line 67. 69 is an isopropanol liquid take-out line connecting the tank 66 and the suction side of the pump 41 of the liquid return line 40, and 70 is an on-off valve provided in the line 69.

In a chemical heat pump configured as shown in Figure 1, isopropanol is used as a reactant,
The endothermic reaction is carried out in the dehydrogenation reactor 1 using waste heat of about 80°C as a heat source, and the exothermic reaction is carried out at about 200°C in the hydrogenation reactor 4. a condenser 14 for condensing acetone and separating it from hydrogen;
A separation column 21 for vaporizing the condensed acetone, a hydrogen gas holder 56. Since it has an acetone liquid storage tank 61, an isopropanol liquid storage tank 66, etc., each substance can be transferred and stored between the dehydrogenation reaction side and the hydrogenation reaction side.
Hydrogen is carried out in the gaseous state, and acetone and isopropanol are carried out in the liquid state.

That is, to explain each device, the condenser 14 is as follows:
Gaseous acetone and hydrogen generated in the distillation column 2 are introduced and cooled to condense the acetone, and the hydrogen separated here is sent to the low temperature side inlet of the heat exchanger 3 via the hydrogen gas line 18.

On the other hand, the acetone condensed in the condenser 14 reaches the condensate storage tank 19 via the condensate line 20, and further flows through the first acetone line 22 by the pump 25, and a portion passes through the second acetone line 25 for distillation. It is supplied to the inner upper part of the column 2, and the other part is supplied to the inner upper part of the separation column 1 through the fifth acetone liquid line 24.

In the distillation column 2, the acetone liquid is supplied from the second acetone liquid line 23 and falls from above.

It comes into direct contact with the gaseous inglobanol, acetone, and hydrogen generated in the dehydrogenation reactor 1 and introduced into the distillation column 2, and the liquid acetone evaporates and joins the gaseous acetone and hydrogen and is entrained. The gaseous isopropanol condenses and reaches the bottom of the column.

The cooler 28 cools isopropanol, which is a reaction product gas, and acetone and hydrogen, which are unreacted gases, from the high-temperature side outlet of the heat exchanger 3, so that some isopropanol is condensed and the rest is separated using a gaseous fluid. The central part of the column 21 is fed.

In the separation column 21, the acetone liquid supplied from the acetone liquid 32nd inn 24° and falling from above comes into direct contact with the fluid supplied from the cooler 28.

The liquid acetone is evaporated, and among the fluids supplied from the cooler 28, Ingropanol is condensed and reaches the bottom of the tower, while the others are combined with hydrogen in the hydrogen gas line 18 by the blower 55 and sent to the heat exchanger 3. is supplied to the cold side inlet of the

The reboiler 51 provides the separation tower 21 with the amount of heat that is insufficient to evaporate the entire amount of the acetone liquid dropped by the separation tower 21. That is, the reboiler 31 is provided to supplement and adjust the amount of heat that is insufficient in the separation column 21.

The pump 41 pumps liquid ingropanol accumulated at the bottom of the separation column 21 to the distillation column 2.

When there is excess hydrogen generated in the condenser 14, the hydrogen gas holder 56 closes the on-off valve (not shown) provided in the hydrogen gas take-out line 60 and closes the on-off valve 59 on the hydrogen gas storage line 57. When the hydrogen is opened, the compressor 58 is operated and the excess hydrogen is injected and stored. Conversely, when there is a shortage, the on-off valve 59 is closed and the compressor 58 is operated.
is stopped, the on-off valve of the hydrogen gas take-out line 60 is opened, and the stored hydrogen is supplied from the line 60 to the hydrogen gas line 18.

In addition, during steady operation with no excess or shortage of hydrogen, compressor 5
8 is stopped, and both the on-off valve 59 and the valve of the hydrogen gas extraction line 60 are closed.

When the acetone liquid generated in the condenser 14 and stored in the condensate storage tank 19 is in excess, the acetone liquid storage tank 61 opens the on-off valve 66 and pumps the acetone liquid into the 32nd inn 24 using the pump 25. The surplus of the flowing acetone liquid is stored, and if there is a shortage, the on-off valve 6 is used.
3 is closed and the pump 65 is operated to supply the stored acetone solution from the acetone solution take-out line 64 to the acetone line 24.

In addition, during steady operation where there is no excess or shortage of acetone, the on-off valve 63
is kept closed and the pump 65 is stopped.

The isopropanol liquid storage tank 66 is equipped with an on-off valve 6 when there is excess isopropanol liquid generated in the separation column 21.
8 is opened and the on-off valve 70 is closed, and the excess isopropanol liquid flowing through the liquid return line/40 is transferred to the ingbanol liquid storage line 67 by the discharge force of the pump 41.
On the contrary, if there is a shortage, the on-off valve 68 is closed and the on-off valve 70 is opened to transfer the stored isopropanol liquid to the isopropanol liquid take-out line 69.
The water is sucked into the pump 41 from there. Note that during steady operation where there is no excess or deficiency in the isopropanol liquid, the on-off valves 68 and 70 are kept closed.

Therefore, gaseous acetone and hydrogen are supplied from the unreacted gas line 46 to the chemical heat pump ■r diureation reactor 4 shown in FIG. A hydrogenation reaction of
In addition, if there is an excess or deficiency in the unreacted material or the reacted material, hydrogen gas is added to the tank.56. Acetone liquid storage tank 61. The isopropanol liquid storage tank 66 allows storage and release to be adjusted separately.

Effects of the Invention The present invention provides a chemical heat pump that uses inglobanol as a reactant, and a condenser that introduces gaseous acetone and hydrogen from a distillation column and cools the acetone to condense the acetone and separate it from the hydrogen. A separation column that introduces liquid acetone generated in the condenser and heats and vaporizes it with the reaction products and unreacted substances from the high temperature side of the heat exchanger, and the hydrogen separated in the condenser and The gaseous acetone generated in the separation tower.

Both are sent to the low temperature side inlet of the heat exchanger.

The heat exchange in the heat exchanger and the hydrogenation reaction in the hydrogenation reactor are carried out as specified without any problems. Moreover, a hydrogen gas holder is provided between the hydrogen gas line connecting the condenser and the low-temperature side inlet of the heat exchanger to temporarily store and flow hydrogen gas, and a hydrogen gas holder is provided which allows hydrogen gas to temporarily flow in, store and flow out, and liquid acetone is transferred to the separation column. An acetone liquid tank is used to temporarily store and discharge liquid acetone between the supply acetone liquid line and a liquid return line that supplies condensed isopropanol from the separation column to the distillation column. Since it is equipped with an isopropanol liquid storage tank from which acetone is temporarily stored and discharged, hydrogen, acetone, and isopropanol can be stored and released separately if there is an excess or deficiency of unreacted substances or reacted substances. Therefore, in the relationship between the waste heat side and the heat use side, if there is surplus heat from the waste heat source, it will be stored, and if there is a shortage, the stored heat will be released, and it is always reasonable to do so. It is possible to utilize waste heat.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram of a conventional chemical heat pump. DESCRIPTION OF SYMBOLS 1... Dehydrogenation reactor, 2... Distillation column, 5... Heat exchanger, 4... Hydrogenation reactor, 14... Condenser, 18
...Hydrogen gas line, 21,, separation column, 22, 23
, 24. ...Acetone liquid line, 25...Pump, 5
5..., blower, 40.・Liquid return line, 41...
Pump, 56... Hydrogen gas holder, 61... Acetone liquid storage tank, 66... Innoproper tool liquid storage tank.

Claims (1)

[Claims] 1. A dehydrogenation reactor that decomposes liquid isopropanol into gaseous acetone and hydrogen using waste heat as a heat source, and a dehydrogenation reactor that decomposes liquid isopropanol into gaseous acetone and hydrogen, and cools the gaseous substance generated in this dehydrogenation reactor to convert it into gaseous acetone and hydrogen. A distillation column condenses and separates the accompanying gaseous isopropanol, and the unreacted gas of acetone and hydrogen from this distillation column is introduced and generated by hydrogenation reaction to generate gaseous isopropanol as the reaction product gas. A hydrogenation reactor is provided between the distillation column and the hydrogenation reactor to return gaseous acetone and hydrogen flowing from the distillation column to the hydrogenation reactor from the hydrogenation reactor to the distillation column. In a chemical heat pump, the gaseous acetone and hydrogen from the distillation column are introduced and the acetone is condensed. a hydrogen gas line for supplying the hydrogen separated by the condenser to the low-temperature side inlet of the heat exchanger; and a hydrogen gas line for introducing liquid acetone condensed in the condenser to the high-temperature side of the heat exchanger. a separation tower that heats and vaporizes the reaction products and unreacted materials from the separation tower, and a blower that supplies the gaseous acetone and unreacted materials vaporized in the separation tower to the low-temperature side inlet of the heat exchanger; A pump that supplies a part of the liquid acetone condensed in the condenser to the inner upper part of the distillation column and another part to the inner upper part of the separation column, and a pump that supplies the isopropanol condensed in the separation column. a hydrogen gas holder that is provided with a pump that supplies the distillation column and that temporarily stores and stores hydrogen gas between it and the hydrogen gas line; and an acetone liquid line that supplies liquid acetone to the separation column; Liquid acetone is temporarily stored between an acetone liquid storage tank where liquid acetone is temporarily stored and discharged, and a liquid return line which supplies condensed isopropanol from the separation column to the distillation column. A heat storage device for a chemical heat pump, characterized in that it is equipped with an isopropanol liquid storage tank for storing and discharging an isopropanol solution.