JPH0656909A - Temperature control device of reactor - Google Patents

Abstract

PURPOSE:To accurately control the polymn. temp. in a reactor by feeding a monomer into the reactor, heating the monomer, feeding a catalyst, and, after a predetermined time, lowering rapidly the temp. of water fed into a jacket. CONSTITUTION:After a monomer is fed into a reactor 1, the opening of a mixing control valve 10 is controlled with a jacket inlet temp. controller 18 to mix warm water 11 with an industrial water 12 in a suitable ratio, controlling the temp. 16 at the inlet of a jacket 2 and elevating the monomer temp. 15 in the reactor 1 to a specified temp. Then, a polymn. catalyst is fed into the reactor 1 and simultaneously the opening of the mixing control valve 10 is controlled with the jacket inlet temp. controller 18 so that the industrial water 12 only is fed into the jacket 2. After a predetermined time, the opening of a brine flow control valve 8 is controlled with the jacket inlet temp. controller 18 to control the flow rate of a brine into a brine cooler 9, further lowering the temp. 16 at the inlet of the jacket 2. Thus the polymn. can be carried out at a predetermined temp.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature control device for a reactor, in which a jacket for controlling the internal temperature is provided on the outer peripheral portion of the reactor, and the waste water passing through the jacket is supplied again into the jacket. It is applied to a pressure-sensitive adhesive production line in which a brine cooler is installed in the circulation system.

[0002]

2. Description of the Related Art In the process of manufacturing an adhesive, there is a reaction control step in the middle of the process. In such a reaction control process, various temperature control systems for accurately controlling the polymerization reaction have been proposed, and the temperature control system of the double kettle reactor disclosed in Japanese Utility Model Publication No. 3-23748 is one of them. is there.

This temperature control system detects the internal temperature of the reactor and inputs it to the internal temperature controller of the reactor. The output of this internal temperature controller of the reactor is taken into the inlet temperature controller of the jacket and supplied to the jacket. The temperature of hot water is controlled. Then, hot water adjusted to a predetermined temperature in the hot water tank is supplied to the jacket by adjusting the mixing ratio of steam and cold water.

[0004]

Generally, in the temperature control device of the reactor, there is a time delay of several minutes or more before changing the jacket temperature and responding. In particular, in the production of pressure-sensitive adhesives, a large amount of heat is generated immediately after the polymerization catalyst is charged, and the internal temperature of the reactor rises significantly. Therefore, if the cooling timing is delayed, phenomena such as overshoot and runaway occur, the internal temperature becomes unstable and the quality deteriorates, and there is a safety problem.

Particularly, in the above-mentioned conventional temperature control system, since hot water once stored in the hot water tank is supplied to the jacket, even if an overshoot or runaway occurs,
It is difficult to rapidly reduce the temperature of hot water, and the above-mentioned problems remain.

The present invention has been made in view of the above circumstances, and an object thereof is to reduce the temperature of water supplied to a jacket at once in a reactor for a predetermined time after the polymerization catalyst is charged. An object of the present invention is to provide a temperature control device for a reactor that can accurately control the reaction temperature in the above.

[0007]

In order to solve the above problems, the temperature control device for a reactor according to the present invention is provided with a jacket for controlling the internal temperature on the outer peripheral portion of the reactor, and Apply the wastewater that has passed through the jacket again to the inside of the jacket by applying it to the adhesive production line where a brine cooler is installed in the circulation system and detect the internal temperature of the reactor. Temperature detector for detecting the inlet temperature of the supplied water, a mixing control valve for adjusting the mixing ratio of the hot water of the supplied water and the industrial water, and a reactor by the internal temperature detector While controlling the opening and closing of the mixing control valve based on the internal temperature of the jacket and the inlet temperature of the jacket by the inlet temperature detector, a predetermined time after the polymerization catalyst is charged into the reactor. During it is configured to include a jacket inlet temperature controller for controlling the mixing control valve so as to supply only industrial water in the jacket.

[0008]

The jacket inlet temperature controller first controls the inlet temperature of the jacket by mixing hot water and industrial water to raise the monomer temperature to a predetermined temperature. Next, the mixing control valve is controlled so that the water supplied to the jacket is switched to only industrial water in accordance with the timing of charging the polymerization catalyst. As a result, the water supplied to the jacket is cooled all the way to the temperature of the industrial water. Then, after a predetermined time, the normal control is restored again.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the overall structure of a temperature control device for a reactor according to the present invention.

In the figure, the reactor 1 is provided with a jacket 2 for controlling the internal temperature on the outer peripheral portion thereof. The pipe on the output side of the jacket 2 is branched into a discharge pipe 3 for discharging the supply water in the jacket 2 to the outside of the system and a circulation pipe 4 for circulating the water in the jacket 2 again.
The discharge pipe 3 is provided with a discharge valve 5, and the circulation pipe 4 is provided with a circulation valve 6. Also, this circulation pipe 4
Is connected to the input side of the jacket 2 via a cold water circulation pump 7 and a brine cooler 9. Further, the brine cooler 9 is provided with a brine flow control valve 8.

On the other hand, a hot water pipe 11 for supplying hot water and an industrial water pipe 12 for supplying industrial water are connected to the mixing control valve 10, and the output side of the mixing control valve 10 is a pipe 13. It is connected to the input side of the cold water circulation pump 7 via.

In the pressure-sensitive adhesive production line thus constructed, an internal temperature detector 15 for detecting the internal temperature is provided inside the reactor 1, and a pipe 4a for connecting the brine cooler 9 and the jacket 2 is provided. In addition, a jacket inlet temperature detector 16 for detecting the temperature of the supply water flowing near the inlet of the jacket 2 is provided.

The internal temperature data detected by the internal temperature detector 15 is led to the reactor internal temperature controller 17, and the jacket inlet temperature data detected by the jacket inlet temperature detector 16 is the jacket inlet temperature data. It is led to the temperature controller 18. Further, the output of the reactor internal temperature controller 17 is led to the jacket inlet temperature controller 18, and the output of the jacket inlet temperature controller 18 is used as a control signal for controlling the opening / closing of each valve. 10 and the brine flow rate control valve 8.

The jacket inlet temperature controller 18 determines the internal temperature of the reactor 1 (reaction temperature) based on the output of the reactor internal temperature controller 17 and the jacket inlet temperature data detected by the jacket inlet temperature detector 16. The opening / closing control of the mixing control valve 10 and the brine flow rate control valve 8 is performed so that) becomes a preset target temperature.

Next, the operation of the temperature adjusting device applied to the manufacturing line having the above-mentioned structure will be described.

In this example, a case where an acrylic pressure-sensitive adhesive is manufactured by the reactor 1 having the above-mentioned structure will be described. Here, the internal volume of the reactor 1 is 500 liters, the raw material and the compounding composition of the adhesive are butyl acrylate: 97 parts, acrylic acid: 3 parts, ethyl acetate: 100 parts, and BPO (benzoyl peroxide) as a polymerization catalyst. Was used at a target temperature of 70 ° C. The hot water in the hot water pipe 11 was set to about 90 ° C, and the industrial water in the industrial water pipe 12 was set to about 40 ° C. 2 is a graph showing the relationship between the jacket temperature and the reaction temperature by the device of the present invention,
The following description will be made with reference to FIG.

When the production of the acrylic pressure-sensitive adhesive is started (indicated by time t1 in FIG. 2), the jacket inlet temperature controller 18 first controls the opening of the mixing control valve 10 to appropriately mix hot water and industrial water. The temperature of the inlet of the jacket 2 is controlled to raise the temperature of the monomer in the reactor 1 to 70 ° C. Next, the jacket inlet temperature controller 18 controls the opening degree of the mixing control valve 10 in accordance with the timing of introducing the polymerization catalyst (indicated by time t2), and the water supplied to the jacket 2 is industrial water (about 40 ° C.). The mixing control valve 10 is controlled so that it becomes only. As a result, the water supplied to the jacket 2 is cooled all the way to the industrial water temperature of about 40 ° C. and the reactor 1 is cooled rapidly, so that the reaction temperature can be controlled without delay. In this way, only the industrial water is continuously supplied to the jacket 2 for the predetermined time T1 until the time t3.

As a result, as shown in FIG. 2, although the reaction temperature reaching the target temperature (70 ° C.) slightly exceeds the target temperature after that, the reaction temperature does not substantially exceed the target temperature and is almost along the target temperature. Transition to.

On the other hand, when the polymerization catalyst is put into the reactor 1 and a predetermined time T1 elapses, the jacket inlet temperature controller 18 then controls the opening of the brine flow control valve 8.
The flow rate to the brine cooler 9 is adjusted, the temperature at the inlet of the jacket 2 is further lowered, and the temperature is cooled to about 10 ° C. Thereby, the reactor 1 is further cooled, so that the reactor 1
The internal reaction temperature will change along the target temperature without overshooting.

Thus, only the industrial water is used for the jacket 2
The temperature of the jacket can be immediately changed by directly supplying the temperature to the temperature control device, so that the temperature can be controlled without a response delay. As a result, the actual reaction temperature could be controlled within a range of ± 2 ° C or less of the target temperature, and a high quality adhesive could be manufactured.

FIG. 3 shows the results when the reaction temperature is controlled by the conventional temperature control device. As shown in the figure, in the conventional apparatus, when the polymerization catalyst is supplied (time t2), the reaction temperature largely overshoots the target temperature due to the control response delay. As a result, the accuracy of the reaction temperature could not be set to ± 4 ° C or lower.

[0023]

The reactor temperature control apparatus according to the present invention comprises an internal temperature detector for detecting the internal temperature of the reactor and an inlet temperature detector for detecting the inlet temperature of the feed water supplied into the jacket. Mixing based on the internal temperature of the reactor by the internal temperature sensor and the inlet temperature of the jacket by the inlet temperature sensor, and the mixing control valve that controls the mixing ratio of the hot water supplied into the jacket and the industrial water. A structure with a jacket inlet temperature controller that controls the opening and closing of the control valve and controls the mixing control valve so that only the industrial water is supplied to the jacket for a predetermined time after the polymerization catalyst is charged into the reactor. As a result, the reaction temperature that has reached the target temperature will change substantially along the target temperature without significantly exceeding the target temperature, and it is possible to control the reaction temperature without a response delay. It is possible to produce high quality pressure-sensitive adhesive. Also, when cooling after the polymerization catalyst is charged, if the cooling is insufficient with only the supply of industrial water, it is switched to a brine cooler, so even if the internal temperature of the reactor fluctuates significantly due to unpredictable disturbance, Control without response delay is possible. Further, by providing the brine cooler in the circulation system, various effects can be obtained such that the capacity of the cooler can be reduced and the facility cost can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a temperature control device for a reactor according to the present invention.

FIG. 2 is a graph showing the relationship between jacket temperature and reaction temperature according to the temperature control device of the present invention.

FIG. 3 is a graph showing the relationship between jacket temperature and reaction temperature by a conventional temperature control device.

[Explanation of symbols] 1 reactor 2 jacket 9 brine cooler 10 mixing control valve 11 hot water piping 12 industrial water piping 15 internal temperature sensor 16 jacket inlet temperature sensor 17 reactor internal temperature controller 18 jacket inlet temperature control Total

Claims (1)

[Claims] 1. An adhesive provided with a jacket for controlling an internal temperature on an outer peripheral portion of a reactor, and a brine cooler provided in a circulation system for supplying waste water passing through the jacket into the jacket again. In the production line, an internal temperature detector for detecting an internal temperature of the reactor, an inlet temperature detector for detecting an inlet temperature of the feed water supplied into the jacket, and a feed water supplied into the jacket. Mixing control valve for adjusting the mixing ratio of the hot water and industrial water, the opening and closing control of the mixing control valve based on the internal temperature of the reactor by the internal temperature detector and the inlet temperature of the jacket by the inlet temperature detector. In addition, the mixing control valve is controlled so that only industrial water is supplied to the jacket for a predetermined time after the polymerization catalyst is charged into the reactor. The reactor temperature control apparatus characterized by comprising a jacket inlet temperature controller.