Heat recovery device

Abstract

Disclosed are a heat recovery device and a heat recovery method. According to the heat recovery device, it is possible to recovery heat which is discontinuously generated in a batch reactor. In addition, a heat-exchanged heat exchange medium is supplied to a heat storage facility so that various kinds and a great quantity of steams can be produced, if necessary, thereby utilizing these produced steams in various industrial fields.

Claims

1. A heat recovery device, comprising an insulated tank in which saturated water is stored, a reactor and a heat exchanger, each of which comprises an inlet line and an outlet line, wherein a stream discharged from the reactor enters the heat exchanger along the outlet line of the reactor and is heat-exchanged with the saturated water or a heat exchange medium entering the heat exchanger, and the stream then enters the reactor along the inlet line of the reactor, wherein the reactor is a batch reactor which discontinuously generates a heat source.

2. The heat recovery device of claim 1, wherein the stream discharged from the reactor is heat-exchanged with the heat exchange medium, and wherein the heat exchange medium is condensed water.

3. The heat recovery device of claim 1, wherein the heat exchanger is installed at an inside or an outside of the insulated tank.

4. The heat recovery device of claim 3, wherein the heat exchanger is installed at an outside of the insulated tank, the stream discharged from the reactor enters the heat exchanger along the outlet line of the reactor and is heat-exchanged with the heat exchange medium entering the heat exchanger along the inlet line of the heat exchanger, the stream then enters the reactor along the inlet line of the reactor, and the heat exchange medium after heat exchange enters the insulated tank along the inlet line of the insulated tank.

5. The heat recovery device of claim 3, wherein the heat exchanger is installed inside of the insulated tank in which the saturated water is stored, the stream discharged from the reactor enters the heat exchanger along the outlet line of the reactor and is heat-exchanged with the saturated water stored in the insulated tank, the stream then re-enters the reactor along the inlet line of the reactor.

6. The heat recovery device of claim 4, wherein a temperature of the stream entering the reactor and a temperature of the saturated water stored in the insulated tank satisfy the following General equation 1:
5 C.T.sub.RinT.sub.SW70 C.[General equation 1] wherein, T.sub.Rin represents the temperature of the stream entering the reactor, and T.sub.SW represents the temperature of the saturated water stored in the insulated tank.

7. The heat recovery device of claim 6, wherein the stream entering the reactor is a stream of a condensed reactant.

8. The heat recovery device of claim 5, wherein the condensed water enters the insulated tank along the inlet line of the insulated tank.

9. The heat recovery device of claim 1, wherein the stream discharged from the reactor is a stream of a gas-phase reactant.

10. The heat recovery device of claim 4, wherein the heat exchange medium after heat exchange is a stream of liquid-phase condensed water, and the device further comprises a circulation line connected to the inlet line of the heat exchanger from a lower portion of the insulated tank, and the saturated water discharged from the lower portion of the insulated tank enters the heat exchanger inlet line along the circulation line.

11. The heat recovery device of claim 4, wherein the insulated tank further comprises a steam discharge line.

12. The heat recovery device of claim 11, wherein a temperature of the stream flowing along the steam discharge line and a temperature of the stream entering the insulated tank along the inlet line of the insulated tank satisfy the following General equation 2:
10 C.T.sub.SoutT.sub.Tin200 C.[General equation 2] wherein, T.sub.Sout represents the temperature of the stream flowing along the steam discharge line, and T.sub.Tin represents the temperature of the stream entering the insulated tank along the inlet line of the insulated tank.

13. The heat recovery device of claim 11, further comprising a control unit configured to control a pressure and/or a production amount of the steam.

14. A heat recovery method, comprising; introducing a stream discharged from a batch reactor to a heat exchanger and heat-exchanging with saturated water stored in an insulated tank or heat exchange medium entering the heat exchanger; and re-introducing the stream, which is discharged from the batch reactor and heat-exchanged with the saturated water or the heat exchanged medium to the batch reactor.

15. The heat recovery method of claim 14, wherein the stream discharged from the batch reactor to the heat exchanger is heat-exchanged with the heat exchange medium, wherein the heat exchange medium is condensed water.

16. The heat recovery method of claim 14, further comprising introducing the condensed water or the heat exchange medium after heat exchange to the insulated tank.

17. The heat recovery method of claim 16, wherein a temperature of the stream entering the reactor and a temperature of the saturated water stored in the insulated tank satisfy the following General equation 1:
5 C.T.sub.RinT.sub.SW70 C.[General equation 1] wherein, T.sub.Rin represents the temperature of the stream entering the reactor and T.sub.SW represents the temperature of the saturated water stored in the insulated tank.

18. The heat recovery method of claim 16, further comprising discharging steam from an upper portion of the insulated tank.

19. The heat recovery method of claim 18, wherein a temperature of the steam discharged from the upper portion of the insulated tank and a temperature of the condensed water or the heat-exchanged heat exchange medium entering the insulated tank satisfy the following General equation 2:
10 C.T.sub.SoutT.sub.Tin200 C.[General equation 2] wherein, T.sub.Sout represents the temperature of the steam discharged from the upper portion of the insulated tank and T.sub.Tin represents the temperature of the condensed water or the heat-exchanged heat exchange medium entering the insulated tank.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a graph typically showing an energy consumption amount according to a time in a batch reactor;

(2) FIG. 2 is a view exemplarily showing one embodiment of a heat recovery device of the present application;

(3) FIG. 3 is a view exemplarily showing another embodiment of a heat recovery device of the present application;

(4) FIG. 4 is a view exemplarily showing further another embodiment of a heat recovery device of the present application;

(5) FIG. 5 is a view showing an device according to the comparative example;

(6) FIG. 6 is a view showing a heat recovery process of the present application; and

(7) FIG. 7 is a graph showing variations of an opening/closing degree of a valve, the amount of saturated water in a tank, an internal temperature of the tank, an internal pressure of the tank, a flow rate of steam according to a heat recovery process time and a flow rate of stream of gas-phase reactants discharged from a batch reactor in one embodiment of the present application.

BEST MODE FOR CARRYING OUT THE INVENTION

(8) Hereinafter, the device and the method of the present application are described in detail with reference to the examples and the comparative example. However, the device and the method of the present application are not limited to the below examples.

Example 1

(9) Heat was recovered by means of the heat recovery device in which the heat exchanger was installed at an outside of the insulated tank as in FIG. 3. Specifically, the gas-phase reactant stream having a temperature of 165 C. and discharged from the batch reactor entered the heat exchanger. Separately, the condensed water of 115 C. and 4.8 kgf/cm.sup.2 entered the heat exchanger through the inlet line and the gas-phase reactant stream, which entered the heat exchanger, exchanged heat with the condensed water in the heat exchanger. The heat-exchanged reactant stream was condensed and then re-introduced into the batch reactor under the condition of a temperature of 163 C. Meanwhile, the heat-exchanged condensed water, which was under the condition of 160 C. and 4.8 kgf/cm.sup.2, entered the insulated tank in which the saturated water having a temperature of approximately 130 C., and a valve installed on the steam discharge line of the insulated tank was opened to decrease a pressure in the insulated tank and discharge the steam which was under the condition of approximately 120 C. and 2 kgf/cm.sup.2. In addition, the saturated water, which was under the condition of approximately 130 C. and 5 kgf/cm.sup.2, was discharged from a lower portion of the insulated tank, and was then mixed with the condensed water, which was under the condition of 115 C. and 4.8 kgf/cm.sup.2 and entered the heat exchanger. Then, the saturated water and the condensed water entered the heat exchanger.

Example 2

(10) Heat was recovered by means of the heat recovery device configured to allow the stream discharged from the reactor to directly exchange heat with the saturated water in the insulated tank as in FIG. 4. Specifically, the gas-phase reactant stream, which had a temperature of 165 C. and was discharged from the batch reactor, entered the heat exchanger installed in the insulated tank in which the saturated water having a temperature of approximately 130 C. was stored, and a pipeline in which the gas-phase reactant stream flowed was in direct with the saturated water through the heat exchanger to allow the reactant stream to exchange heat with the saturated water. The heat-exchanged reactant stream was condensed and then re-entered the batch reactor under the condition of a temperature of 163 C., and the valve installed on the steam discharge line of the insulated tank was opened to decrease a pressure in the insulated tank and discharge the steam which was under the condition of approximately 120 C. and 2 kgf/cm.sup.2.

Comparative Example

(11) The gas-phase reactant stream which had a temperature of 180 C. and was discharged from the batch reactor as shown in FIG. 5 was cooled by cooling water having a temperature of approximately 35 C. and was then condensed to a temperature of approximately 178 C. Subsequently, the condensed stream re-entered the batch reactor.

Experimental ExamplePerforming a Simulation Experiment

(12) In order to more accurately find out the process time, an opening/closing degree of the valve according to a flow rate of the gas-phase reactant stream discharged from the batch reactor, the amount of the saturated water in the tank, the internal temperature of the tank, the internal pressure of the tank and the amount of the steam in the above embodiments, the process simulation experiment as shown in FIG. 6 was carried out under a dynamic condition using the Aspen HYSYS, the experiment results were shown in FIG. 7.

(13) It can be found that, as shown in FIG. 7, the amount of the saturated water in the water, the internal temperature and the internal pressure of the tank were increased at the time period between approximately 167.7 hours and 169.8 hours during which the flow rate of the gas-phase reactant stream discharged from the batch reactor was explosively increased, and the amount of the reactant stream was gradually decreased from the time between approximately 170 hours and 173.8 hours to the time at which the reaction was finished so that the amount of the saturated water in the tank, the internal temperature and the internal pressure of the tank were also gradually decreased. However, it can be found that the amount of the gas-phase reactant stream was disappeared between approximately 174 hours and 175.8 hours during which, after finishing the reaction, the reaction was halted until the next operation so that waste heat was discontinuously produced. In this case, it can be found that even though the amount of the saturated water in the tank, the internal temperature and the internal pressure of the tank were rapidly decreased, the steam was continuously produced so that it is possible to continuously produce the steam using the waste heat which was discontinuously generated.