JPH05187749A - Reduced pressure cooling device - Google Patents

Abstract

PURPOSE:To provide a reduced pressure cooling device in which a large amount of cooling water may not be required due to evaporative cooling and water cooling and further a cooling disturbance and delay in cooling are not generated. CONSTITUTION:A cooling water supplying pipe 12 is connected to a jacket part 5 of a reaction device 21 through a flow, adjusting valve 13. A temperature sensor 15 for use in sensing the temperature of cooling water within the reaction device 21 and a temperature sensor 16 for use in sensing the temperature of the cooling water in the jacket part 5 are fixed. The temperature sensors 15, 16 and the flow, adjusting valve 13 are connected through a control part. A lower part of the jacket part 5 is connected to an ejector 32 of a combined pump 22. The ejector 32, a tank 31 and the pump 30 are made to communicate with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cooling an object to be cooled by reducing the pressure in a cooling chamber, and in particular, vaporizing cooling by evaporation latent heat of cooling water and cooling water by cooling water. Regarding a cooling device. Specifically, the present invention relates to a cooling device for a reaction kettle that performs various reactions, and a cooling device for foods, films, synthetic fibers and the like. These things may be altered or cause an abnormal reaction due to a slight temperature change, and the improvement of cooling temperature control accuracy has a great influence on product quality and productivity.

[0002]

2. Description of the Related Art As a vaporization cooling device for a reaction vessel as an example of a conventional reduced pressure cooling device, for example, Japanese Patent Laid-Open No. 1-31533
There is one disclosed in Japanese Patent No. This is a combination pump that combines an ejector, a tank, and a pump, a switching valve means that can supply a part of the discharge water of the combination pump to the fluid chamber of the reaction vessel, and a temperature control that controls the temperature of the fluid passing through the inside of the ejector. And discharge water from a combination pump for cooling is supplied to the fluid chamber of the reaction vessel to evaporatively cool the reaction vessel. The fluid chamber is depressurized by the suction action of the ejector, and the supplied discharge water as cooling water takes the heat of the reaction kettle and immediately vaporizes it, thereby efficiently cooling it with a large amount of latent heat of vaporization.

[0003]

The above-mentioned conventional device has a problem that the temperature of the object to be cooled cannot be controlled with high accuracy. This is because it is necessary to control the evaporation amount of the cooling water in order to control the temperature of the object to be cooled, and it is necessary to accurately control the depressurized state of the fluid chamber in order to control the evaporation amount. However, in order to control the depressurized state, it is necessary to control the temperature of the fluid passing through the ejector. Actually, it is necessary to control the fluid temperature with high precision by means of the jule heat or heat dissipation associated with the pump and circulation. Because it is difficult. Also, instead of evaporative cooling by latent heat of vaporization of cooling water,
Since the amount of cooling heat is small with only simple water cooling, there are problems that a large amount of cooling water is required, uneven cooling occurs, or a cooling delay occurs.

Therefore, a technical object of the present invention is to obtain a decompression cooling device which does not require a large amount of cooling water, does not cause uneven cooling or delay, and can cool an object to be cooled with high temperature accuracy. ..

[0005]

The structure of the reduced pressure cooling device of the present invention is as follows. A decompression cooling chamber for cooling the object to be cooled, a cooling water supply passage communicating with the decompression cooling chamber, a flow rate control valve provided in the cooling water supply passage, and a decompression pump communicating with the decompression cooling chamber, A temperature detecting means for detecting the temperature of the object to be cooled and the cooling water is provided, and a control section for controlling the opening and closing of the flow rate adjusting valve by a detection signal from the temperature detecting means is provided.

[0006]

Function The decompression cooling chamber is decompressed by the communicating decompression pump. On the other hand, cooling water is supplied to the decompression cooling chamber from the cooling water supply passage via the flow rate control valve. The cooling heat quantity for cooling, that is, the total heat transfer quantity: Q can be calculated by the following general formula. Q = A ・ U ・ ΔT where A: cooling heat transfer area U: overall heat transfer coefficient ΔT: temperature difference between the object to be cooled and cooling water The cooling heat transfer area (A) is the shape and size of the cooling chamber. Is a value that is determined when the value is determined, and the overall heat transfer coefficient (U) is a value that is determined when the latent heat of vaporization of cooling water is determined in evaporative cooling.
Therefore, the above ΔT, that is, the temperature of the object to be cooled and the temperature of the cooling water are detected by the temperature detecting means, and the flow control valve is controlled through the control unit so that the temperature difference between them becomes a predetermined value. It is possible to control the amount of cooling heat (Q) and, by extension, control the temperature of the object to be cooled by adjusting.
When the amount of cooling heat is insufficient and it is necessary to further cool the object to be cooled, the opening degree of the flow rate control valve is increased by the detection signal from the temperature detecting means of the object to be cooled and a larger amount of cooling water is supplied. Thus, the object to be cooled is vaporized and water cooled.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The illustrated embodiment will be described in detail. In the present embodiment, an example using a reaction kettle as a reduced pressure cooling device is shown. The reaction vessel 21 having the jacket portion 5 as the decompression cooling chamber, the combination pump 22 as the decompression pump, the cooling water supply passage 12 and the flow rate control valve 13 constitute a decompression cooling device. The reaction vessel 21 forms a jacket portion 5 over substantially the entire circumference, and is provided with a raw material inlet 3, a supply pipe 8 through a raw material supply valve 7, a product outlet 4, and an agitator 6, and the jacket portion 5 is supplied with cooling water. A port 1 and outlets 2 and 9 for cooling liquid or vaporized vapor are provided. A temperature sensor 15 as a temperature detecting means for detecting the temperature of the object to be cooled is provided in the reaction vessel 21.
At the same time, the temperature sensor 16 for detecting the temperature of the cooling water is attached inside the jacket 5. The temperature sensors 15 and 16 are connected to the flow rate control valve 13 via a control unit (not shown).

The combination pump 22 as a pressure reducing pump comprises a tank 31, a pump 30, and an ejector 32. The pump 30 has a structure in which the suction side is connected to the tank 31, the discharge side is connected to the nozzle 33 of the ejector 32, and the diffuser 34 of the ejector 32 is connected to the upper space of the tank 31 to react with the ejector 32. The outlets 2 and 9 of the shuttle 21 are connected via valves 10 and 11. Tank 3
1 has a communication hole 35 communicating with the atmosphere in the upper part,
A pipe 36 for adding cooling water is connected to the inside of the tank 31, and a discharge pipe 37 for discharging excess water is connected to the lower portion. The combination pump 22 is configured to supply the cooling water in the tank 31 to the ejector 32 by the operation of the pump 30 to cause the ejector 32 to suck the cooling water, and then to return it to the tank 31. The decompression pump is not limited to the combination pump 22 of the present embodiment, but other conventionally known vacuum pumps can be used.

A heat exchanger 25 is connected to the cooling water supply pipe 12. The heat exchanger 25 adjusts the temperature of the cooling water by communicating the refrigerant supply pipe 26 therein. This heat exchanger 25 is unnecessary if it is not necessary to adjust the temperature of the cooling water.

A control unit (not shown) connected to the flow rate control valve 13 has a storage unit for preliminarily storing an equation Q = A · U · ΔT for calculating a cooling heat quantity, and a setting unit for setting the temperature of the object to be cooled. A built-in computing unit that computes the opening of the flow rate control valve 13 based on the set temperature, a display unit that displays the detected temperature, and the like.

Next, the operation will be described. The pump 30 is driven to cause the ejector 32 to perform a suction action so that the inside of the jacket portion 5 is depressurized. The cooling water supplied to the jacket portion 5 via the flow rate control valve 13 immediately evaporates and evaporates and cools the reaction vessel 21 due to the heat and reduced pressure of the reaction vessel 21. The temperature of the object to be cooled in the reaction vessel 21 is detected by the temperature sensor-15.
The temperature of the cooling water in the jacket portion 5 is detected by the temperature sensor 16, and the opening of the flow rate control valve 13 is increased in the control portion to supply a large amount of cooling water. Is further cooled by evaporative cooling of cooling water and water cooling.

The cooling water in the jacket portion 5 and the vaporized steam generated by the vaporization cooling are sucked into the ejector 32 from the respective outlets 2 and 9 and reach the tank 31. A part of the cooling water is evaporated into the atmosphere through the communication hole 35 or is discharged out of the system through the discharge pipe 37.

[0013]

The present invention has the following effects. By performing evaporative cooling or evaporative cooling and water cooling depending on the temperature of the object to be cooled, a large amount of cooling water is not required as in the case of only water cooling, and uneven cooling or cooling delay may occur. In addition, since the cooling water supplied to the decompression cooling chamber can be kept at a constant temperature without circulation, the temperature of the object to be cooled can be maintained with high accuracy.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of a reduced pressure cooling device of the present invention.

[Explanation of symbols]

 5 Jacket part 12 Cooling water supply pipe 13 Flow rate control valve 15, 16 Temperature sensor 21 Reactor 22 Combined pump 30 Pump 31 Tank 32 Ejector

Claims (1)

[Claims] 1. A decompression cooling chamber for cooling an object to be cooled, a cooling water supply passage communicating with the decompression cooling chamber, a flow rate control valve provided in the cooling water supply passage, and a decompression communicating with the decompression cooling chamber. A decompression cooling device comprising a pump, temperature detecting means for detecting the temperature of an object to be cooled and cooling water, and a control section for controlling the opening and closing of the flow rate adjusting valve according to a detection signal from the temperature detecting means.