JPH0979512A - Low-pressure steam heater by heating medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a low-pressure steam heater by heating medium which makes it possible to rapidly alter the heating steam temperature of the medium. SOLUTION: A boiler 1 for heating medium is connected to the jacket 6 of a reaction kettle 2 via a pressure regulating valve 8 and a vapor-liquid separator 9. The jacket 6 is connected to the ejector 20 of a vacuum pump 7 via a pipeline 16. The pump 7 has the ejector 20, a tank 21, a circulation pump 22 and their connecting pipeline 23. Cooling liquid is supplied to the outer surface of the tank 21. Heating medium 27 in the tank 21 is connected to a cooling tower 34 via a pipeline 36.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating medium for heating an object to be heated by steam of a heating medium, which is used in various heating processes in the petrochemical industry, the synthetic fiber industry, the synthetic resin industry and the like. The present invention relates to a steam heating device.

[0002]

2. Description of the Related Art As an example of a conventional steam heating device using a heat medium, one shown in FIG. 2 has been used.
This is to heat the medium to be heated in the reaction vessel 2 by supplying the heat medium vapor generated in the heat medium boiler-1 as the evaporator of the heat medium to the reaction vessel 2 which is a kind of heat exchanger. , The condensate of the heat medium vapor condensed by heating is caused to flow down into the tank 3,
It is collected in the boiler 1 by the circulation pump 4.

Although various kinds of heat mediums are commercially available and used, those having a lower pressure and a higher temperature are generally used as compared with the steam generated by boiling normal water, and the heating device is highly resistant to heat. It can be heated at a relatively high temperature without pressure design, and is widely used in various heating processes.

[0004]

When the conventional steam heating device using a heat medium is used, there is a problem that the heating temperature cannot be changed promptly. In particular, when the heating temperature of the heating medium vapor was lowered, it could not be changed promptly. This means that the steam pressure must be changed in order to change the temperature of the heat carrier steam, but the steam pressure generated in the evaporator or boiler or the steam pressure can be changed quickly by adjusting various valves. This is because it cannot be done. Further, in order to lower the heating temperature, it is necessary to lower the steam pressure, but in the above-mentioned conventional one, this decrease in steam pressure must wait until the object to be heated deprives the heat of condensation of the heated steam. Therefore, the heating temperature cannot be changed more quickly.

Therefore, a technical object of the present invention is to obtain a low-pressure steam heating device using a heat medium, which can rapidly change the steam heating temperature in heating the heat medium with steam.

[0006]

[Means for Solving the Problems] The technical means of the present invention taken to solve the above-mentioned technical problem is to connect a steam supply pipe of a heat medium to a primary side of a heat exchanger, When recovering the condensed heat medium to a recovery destination such as an evaporator, a vacuum pump consisting of an ejector, a tank, and a circulation pump is connected to the secondary side of the heat exchanger, and the heat medium in the vacuum pump is removed. A cooling tower for cooling is connected.

[0007]

[Operation] By connecting a vacuum pump consisting of an ejector, a tank and a circulation pump to the secondary side of the heat exchanger and connecting a cooling tower for cooling the heat medium in the vacuum pump, the heat medium When changing the steam heating temperature of, the steam temperature is quickly changed by adjusting the temperature of the heat medium that circulates in the vacuum pump by the cooling tower to adjust the vacuum degree of the vacuum pump, that is, the suction amount. However, at the same time, the steam temperature can be changed promptly. By increasing the cooling amount in the cooling tower and lowering the liquid temperature of the heat medium in the vacuum pump, the suction amount of the vacuum pump can be increased and the heating steam pressure can be lowered more quickly. The heating temperature can also be lowered. on the other hand,
If the cooling amount in the cooling tower is reduced and the liquid temperature of the heat medium in the vacuum pump is not lowered, the suction amount of the vacuum pump is reduced or almost eliminated to measure the recovery of the steam pressure and raise the steam heating temperature. be able to.

[0008]

EXAMPLE An example showing a concrete example of the above technical means will be described (see FIG. 1). In this embodiment, an example in which the reaction kettle 2 is used as a heat exchanger is shown, and the same members as those in the prior art shown in FIG.

The heat medium boiler 1 serving as an evaporator is connected to the jacket portion 6 of the reaction kettle 2 and the lower portion of the jacket portion 6 is connected to the vacuum pump 7. The vacuum pump 7 is connected to the tank 3 and the circulation pump 4. The low-pressure steam heating device using the heat medium is configured by connecting to the boiler 1 for heat medium via.

The heating medium boiler 1 and the reaction vessel 2 are connected by a pressure adjusting valve 8, a gas-liquid separator 9 and a heating steam supply pipe 11 via a pressure sensor 10. The pressure adjusting valve 8 adjusts the steam pressure in the heating steam supply pipe 11 detected by the pressure sensor 10 to a predetermined value, and the gas-liquid separator 9 controls the heat medium in the heating steam supply pipe 11. The vapor and the liquid are separated, and only the separated vapor is supplied to the jacket portion 6 of the reaction kettle 2,
The liquid is discharged from the steam trap 12 provided below the liquid. The gas-liquid separator 9 may be of a collision type, a centrifugal type, a filter type, or the like.

A jacket portion 6 arranged on the outer periphery of the reaction kettle 2.
The lower connection port 13 is connected to the ejector 20 of the vacuum pump 7 by a pipe line 16 in which a steam trap 14 and a bypass valve 15 are provided in parallel. Further, the outlet of the steam trap 12 of the gas-liquid separator 9 is connected to the ejector 20 via the conduit 17.

The vacuum pump 7 is composed of an ejector 20, a tank 21, a circulation pump 22 and a connecting pipe line 23. The ejector 20 is formed of a nozzle portion 25 and a diffuser portion 26. The heat medium 27 in the tank 21 is replaced by the tank 2
The cooling tower 34 is connected to the cooling tower 34 from the center of the side portion 1 through a pipe 36 and a pump 37.

The cooling tower 34 is a closed cooling tower, and comprises a fan 30, a nozzle 31, a cooling coil 32, a cooling liquid 33, and a pump 35 for circulating the cooling liquid 33.
Water or a refrigerant can be used as the cooling liquid 33.
The heat medium 27 passing through the inside of the cooling coil 32 is transferred to the fan 30.
Is cooled by evaporation of the air flow and the cooling liquid indicated by the three arrows.

The vacuum pump 7 circulates the heat medium 27 in the tank 21 through the ejector 20 by the circulation pump 22, and the nozzle portion 25 of the ejector 20 generates a suction force corresponding to the temperature of the heat medium 27. The heat medium is sucked from the jacket portion 6 of the reaction vessel 2 and the inside of the jacket portion 6 is maintained at a predetermined pressure state. The liquid temperature of the heat medium 27 can be lowered by increasing the cooling amount in the cooling tower 34.

A part of the connecting pipe line 23 of the vacuum pump 7 is branched to connect the pipe line 38 so that a part of the circulating heat medium is supplied from the pipe line 39 to the tank 3. Four
0 to connect a part of the circulating heat medium to the steam supply pipe 11 for heating
It is injected into the primary side of the gas-liquid separator 9 therein. Even when the heat transfer medium whose pressure is adjusted by the pressure adjusting valve 8 by the pipe 40 becomes superheated steam, a part of the circulating heat transfer medium is injected and heat is exchanged in the gas-liquid separation unit 9 to obtain the saturation temperature. The heat medium vapor can be used.

Next, the operation will be described. Boiler for heat medium-1
The heat medium vapor generated in 1 is supplied to the jacket portion 6 of the reaction vessel 2 after being pressure-adjusted via the pressure adjustment valve 8. The inside of the jacket portion 6 is in a predetermined low pressure state by the suction force of the ejector 20 of the vacuum pump 7, and the heat medium vapor supplied to the jacket portion 6 reaches a predetermined pressure, that is, the vapor temperature, in the reaction vessel. The object to be heated in 2 is heated. The heat medium vapor that has been heated and deprived of heat condenses into a liquid, is sucked by the ejector 20 through the steam trap 14, and reaches the tank 21.

The heat medium 27 in the tank 21 reaches the cooling tower 34 from the pipe 36, is cooled to a predetermined temperature, is supplied to the ejector 20 by the circulation pump 22, and is again jacketed.
Aspirate the heat medium inside. Since the suction force generated by the ejector 20 is determined by the temperature of the fluid passing through the ejector 20, the suction force of the ejector 20, that is, the degree of decompression, is adjusted by appropriately adjusting the liquid temperature of the heat medium 27 in the tank 21. Can be controlled. By controlling the suction force of the ejector 20, the pressure state inside the jacket portion 6 can be controlled, and the pressure inside the jacket portion 6 can be changed from a negative pressure state below atmospheric pressure to a positive pressure state above atmospheric pressure. Can be controlled.

When a heat medium called Dowsum is used as the heat medium, the steam temperature is about 210 ° C when the steam pressure is 0.3 kg in absolute pressure, and about 260 ° C when it is 1.1 km. The steam temperature can be controlled by controlling the steam pressure.

In the present embodiment, when the heating temperature in the jacket portion 6 is changed, it can be carried out promptly by adjusting the liquid temperature of the heating medium by the cooling tower 34.

In this embodiment, the reaction vessel 2 was used as the heat exchanger, but other heat exchangers such as synthetic fibers and synthetic resins, or heat exchangers for foods, medical products, etc. Can also be used as.

[0021]

As described above, according to the present invention, by controlling the liquid temperature of the heat medium in the vacuum pump by the cooling tower, the degree of vacuum of the ejector section of the vacuum pump is adjusted to control the heat medium of the heat medium. It is possible to obtain a low-pressure steam heating device using a heat medium, which can quickly change the heating steam pressure, that is, the heating steam temperature.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a low-pressure steam heating device using a heat medium according to the present invention.

FIG. 2 is a configuration diagram showing a conventional steam heating device using a heat medium.

[Explanation of symbols]

 1 Boiler for heat medium 2 Reaction kettle 6 Jacket 7 Vacuum pump 8 Pressure adjustment valve 9 Gas-liquid separator 14 Steam trap 20 Ejector 21 Tank 22 Circulation pump 27 Heat medium 34 Cooling tower

Claims (1)

[Claims] 1. A secondary side of a heat exchanger in which a steam supply pipe for a heat medium is connected to a primary side of the heat exchanger and the heat medium condensed by the heat exchanger is recovered to a recovery destination such as an evaporator. A low-pressure steam heating device using a heat medium, wherein a vacuum pump consisting of an ejector, a tank and a circulation pump is connected in series to a cooling tower for cooling the heat medium in the vacuum pump.