JPS61208522A - Temperature controller - Google Patents

Abstract

PURPOSE:To control the temperature of a tank with high accuracy by adding the exit temperature signal to an operating signal obtained by the deviation between the intra-tank temperature signal and the temperature setting signal to obtain the target signal of a jacket entrance temperature controller. CONSTITUTION:The temperature of a reaction tank 1 containing a raw material, etc. is controlled by supplying a heat medium 2 to a jacket. The temperature of the tank 1 is detected by an intra-tank temperature detector 4, and the intra- tank temperature signal S1 is sent to an intra-tank temperature controller 23. Then a cooling water control valve 8 and a steam flow rate control valve 9 are opened and closed by the operating signal M. Here the exit temperature detector 20 of the medium 2 is added together with a target production means 22. This means 22 contains the controller 23 which produces the operating signal m1 from the signal S1 and the temperature setting signal Ts and an adder 24 which adds the signal m1 delivered from the controller 23 to the exit temperature signal (d). Then a controller 21 obtains the deviation between the entrance temperature signal P and the signal M1 and carries out a P arithmetic, etc. so as to set the deviation at zero. Then the operating signal Ma is delivered to both valves 8 and 9 respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a concentration control device that controls the temperature inside a reaction tank or the like by heating and cooling it with a heat medium.

[Technical background of the invention]

FIG. 4 is a configuration diagram of a conventional temperature control device, which controls the internal temperature of a reaction tank 1 containing raw materials or intermediate products by supplying a heat medium 2 to the jacket of the reaction tank 1. It is. Note that the reaction is performed while the raw materials or intermediate products are stirred by the stirrer 3. Specifically, the concentration in the tank is controlled as follows. That is, the temperature inside the tank is detected by the temperature detector 4 provided in the reaction tank 1, and the concentration signal S1 in the tank is sent to the humidity controller 5.

This in-tank temperature controller 5 calculates the deviation between the in-tank temperature signal s1 and the temperature setting signal Ts, and adjusts P so as to make this deviation zero.
ID calculations (proportional, integral, and differential calculations) are performed and a position-type target value signal m is output to the jacket inlet temperature controller 6. The jacket inlet temperature controller 6 receives the inlet temperature signal P of the heat medium detected by the inlet temperature detector 7 provided at the jacket inlet, and receives the inlet temperature signal P and the target value from the controller 5. A deviation from the signal m1 is determined, a P calculation, etc. is performed to make this deviation zero, and the operation signal M is output. In this way, the cooling water control valve 8 and the steam flow rate control valve 9 open and close in response to the operation signal M, respectively, and the flow rates of the cooling water 10 and the steam are adjusted.
2 and the heater 13 adjust the temperature of the heat medium 2. As a result, the temperature inside the reaction tank 1 is controlled. In addition,
The cooling water control valve 8 is fully open when the operation signal M is 0%, and as the operation signal M increases, the opening degree decreases and the operation signal becomes 5%.
When it becomes 0% or more, it becomes a closed state. On the other hand, the steam flow rate control valve 9 is in a 0%, ie, closed, state when the operating signal M is 0 to 50%, and when the operating signal is 50% or more, it opens as the operating signal M increases, and becomes fully open at 100%.

By the way, the following requirements are required in petrochemical processes and the like. In other words, high controllability is required to achieve high quality and homogenization of products, and especially when disturbances such as temperature program control, endothermic reactions, and exothermic reactions are involved, high coordination and controllability are required. .

[Problems with background technology]

However, the above device has the following drawbacks. In other words, it is best to adjust the temperature of the heat medium 2 using information on the difference between the jacket inlet temperature and outlet concentration.
Since only the inlet temperature is used, changes in the outlet temperature are not considered, and the configuration does not allow for highly accurate temperature control. In addition, the temperature inside the tank is controlled by a program using a controller, so it will fluctuate slightly. Therefore,
In order to control the temperature inside the tank with high precision, it is best to change the heat transfer efficiency, which is determined by the difference between the inside temperature of the tank and the average temperature at the entrance and exit of the jacket, but the above device does not have this means, and its controllability is limited. The control changes depending on the state. Therefore, the demands for higher quality and uniformity of products have not been satisfied, nor has the demand for labor saving been satisfied.

[Purpose of the invention]

The present invention has been made based on the above-mentioned circumstances, and its object is to provide a temperature control device that can further improve accuracy by taking into account the outlet temperature of the jacket.

[Summary of the invention]

The present invention provides an outlet temperature detector that detects the temperature of the heat medium flowing out from the tank, and generates an operation signal obtained from the deviation between the tank temperature signal from the tank temperature sensor and the set signal in the target creation means. The temperature control device corrects the output temperature signal from the outlet temperature detector according to a change in the output temperature signal and outputs the signal as a target signal to a temperature controller that adjusts the temperature of the heat medium.

[Embodiments of the invention]

Next, before describing the embodiment, the temperature T1 of the heat medium 2 at the jacket inlet will be described. Assuming that the amount of heat required in the reaction tank 1 is Qd, the required amount of heat Qd can be expressed as Qd-V.rho.C.DELTA.TO (1). Here, ■ is the raw material input volume 1, ρ is specific gravity, C is specific heat, ΔT
O is the output of the jacket inlet temperature controller 21.

In addition, the actual input heat amount Qa is expressed as Qa-/Fwdt-pw x Cw (T i -To) (2), where l"w is the flow rate of the heat medium 2, ρW is the specific gravity of the heat medium 2, and CW is the specific heat, T1 is the jacket inlet temperature, and To is the jacket outlet temperature.

Here, if the heat exchange efficiency is η, then Qd-Qa/η (3), so if the jacket inlet temperature T1 is calculated from the above equations (1) to (3), Ti-To+ ■・SC・Δ■C ÷ (η・fFwdt・ρw−Qw) (4). Here, since Fw=constant and every predetermined time interval, /Fwdt=constant. Therefore, the above formula (4) % Formula % (5) Next, a first embodiment of the present invention will be described with reference to the configuration diagram shown in FIG. In this figure, the same parts as in FIG. 4 are given the same reference numerals, and detailed explanation thereof will be omitted. The features of this invention device include an outlet temperature detector 20 that detects the temperature of the heat medium 2 flowing out from the jacket, and an operation signal obtained from the deviation between the tank internal temperature signal S1 and the temperature setting signal TS. The purpose is to provide a target generating means 22 which outputs the target signal M1 of the jacket inlet temperature detector 21 by adding the outlet temperature signal d to m1. Specifically, the target creation means 22 includes an in-tank hot water temperature controller 23 that creates an operation signal m1 from an in-tank concentration signal S1 and a temperature setting signal Ts, and an outlet temperature signal in the operation signal m1 output from this controller 23. and an adder 24 that adds d.

Next, the temperature control of the heat medium 2 in the apparatus configured as described above will be explained. The heat medium 2 is cooled or heated by a cooler 12 or a heater 13 and sent to the jacket of the reaction tank 1 . In this reaction tank 1, heat exchange is performed by a heat medium 2, and heat is supplied to the raw materials and intermediate products in the tank and is discharged. Here, the heat medium temperature at the jacket inlet is detected by the inlet temperature detector 7, and the outlet temperature detector 20
The heat medium temperature at the jacket outlet is detected by On the other hand, the tank temperature detector 4 detects the tank temperature and outputs the tank temperature detection signal S1 to the tank concentration controller 23. This in-tank concentration controller 23 determines the deviation between the in-tank temperature signal S1 and the temperature setting signal Ts, and selects a PID that makes this deviation zero.
The calculation is executed and a speed-type operation signal m1 is output to the adder 24.

Here, the operation signal m1 is (K/η)・ΔTc of equation (5)
corresponds to The adder 24 combines the operating signal m1 and the outlet temperature signal d from the outlet temperature detector 20 (i.e., T in equation (5)).
(equivalent to o) and output to the jacket inlet temperature controller 21 as a target signal. This allows l! Savings 2
1, the target signal M1 is indicative of the jacket inlet temperature Ti shown in equation (5), that is, it is based on the change in the outlet temperature. Thus, the controller 21 calculates the deviation between the inlet temperature signal P and the target signal M1, performs a P calculation etc. to make this deviation zero, and outputs the operation signal Ma to the multi-valve 8.9. As a result, the temperature of the heat transfer medium 2 is adjusted according to the fluctuation of the outlet concentration and is sent to the jacket of the reaction vessel 1.

In this way, in the first embodiment, the outlet temperature signal d detected by the outlet temperature detector 20 is added to the operation signal m1 obtained from the deviation between the tank internal temperature signal S1 and the temperature setting signal TS, and the output temperature signal d detected by the outlet temperature detector 20 is added to Since the configuration uses the target signal of the inlet temperature controller 21, feedforward control is performed based on the outlet temperature, that is, the cooling and heating of the heat medium 2 is adjusted based on the jacket outlet temperature, so that the influence of temperature changes in the control system can be adjusted at any time. By making corrections, this change can be suppressed before it occurs, and the temperature inside the tank can be controlled with high precision.

Next, the second real mttA will be explained with reference to the configuration diagram shown in FIG. Note that the same parts as in FIG. 1 are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

The difference between this apparatus and the apparatus shown in FIG. A target generating means 30 is provided which has a function of correcting the heat exchange rate using the reciprocal of the signal and outputting a target signal for the jacket inlet temperature controller 21 from the tank internal temperature signal and the concentration setting signal Ts. be. Specifically, the target creation means 30 includes an average calculation unit 31 that calculates the average temperature signal of the inlet temperature signal p and the outlet temperature signal 'd, and a subtraction unit 32 that calculates the deviation between the average temperature signal and the tank temperature signal $1. , an absolute value calculation unit 33 that calculates the absolute value of the deviation signal from the subtraction unit 32, and an absolute value calculation unit 33 that calculates the reciprocal of the absolute value from the sieve unit 33 and calculates the inverse of the absolute value from the sieve unit 33
5, and a speed type tank which has a function of correcting the proportional gain by receiving the reciprocal number, and generates and outputs a target signal M2 from the deviation between the tank internal temperature signal S1 and the temperature setting signal Ts. It is composed of an internal temperature controller 34.

Next, the action will be explained. The heat medium 2 is detected at the inlet and outlet of the jacket by an inlet temperature detector 4 and an outlet moisture detector 20, respectively, and the inlet temperature signals S1,
The outlet temperature signal d is sent to the average calculation section 31. This average temperature calculation unit 31 calculates an average temperature signal, that is, (T i −To )/2 from each input temperature signal S1, d, and sends it to the subtraction unit 32, which calculates the temperature inside the tank. Subtract the average temperature signal from the signal $1. That is, (Tx - (T i + To )/2) is calculated and sent to the absolute value calculation section 33 and further sent to the reciprocal number calculation section 35 . As a result, the reciprocal unit 35 outputs 1/l TX - (T i +To )/2 l. In this way, the proportional gain is corrected by the gain adjustment mechanism installed inside the tank temperature controller 34. and,
This tank temperature controller 34 calculates the deviation between the tank temperature signal S1 and the temperature setting signal TS, and performs PID calculation using a modified proportional gain to make this deviation zero. outputs the target signal M2. Here, modifying the above proportional gain is based on the above (5).
The heat exchange efficiency η in the equation will be corrected. therefore,
The heat exchange efficiency η changes in proportion to ΔT (average temperature difference) = ((TX - T I ) + (Tx - To )/2 = Tx - (T I + To )/2, so this change Based on this, the change in efficiency η can be approximated.

Thus, the controller 21 outputs the inlet temperature signal P and the target signal M1.
The operating signal Ma obtained by performing a P calculation or the like to make this deviation zero is output to the joint venture 8.9. As a result, the temperature of the heat transfer medium 2 is adjusted according to the fluctuation of the outlet temperature and is sent to the jacket of the reaction vessel 1.

In this way, in the second embodiment, an average temperature signal is obtained from the outlet temperature signal d and the inlet temperature signal S1, the deviation between this average temperature signal and the bath temperature signal S1 is obtained, and then the deviation signal is calculated. Since the target generation means 30 is configured to correct the heat exchange coefficient using a reciprocal and output a target signal for the jacket inlet temperature controller 21 from the tank internal temperature signal and the temperature setting signal TS, the inlet temperature and the outlet temperature can be adjusted. Since the heat transfer efficiency and rate are corrected based on the difference between the temperature and the temperature, the temperature inside the tank can be controlled with high precision as in the first embodiment.

As described above, the first and second embodiments improve the quality of products,
Uniformity can be achieved.

Note that the present invention is not limited to the above embodiments. For example, each controller may be of either a position type calculation type or a velocity type calculation type. Furthermore, a predetermined method for generating numbers between broken lines in a graph may be used to correct the proportional gain.

In this case, a function generating section storing a function as shown in FIG. 3 may be provided, and the absolute value from the absolute value calculating section 33 may be inputted to the function generating section to provide a gain correction signal to the premises temperature controller 34. Bye.

〔Effect of the invention〕

As described in detail above, according to the present invention, it is possible to provide a temperature control device that can further improve accuracy by taking into account the outlet temperature of the jacket.

[Brief explanation of the drawing]

1 is a block diagram showing a first embodiment of a temperature control device according to the present invention, FIG. 2 is a block diagram showing a second embodiment of a temperature control device according to the present invention, and FIG. 3 is a block diagram showing a second embodiment of a temperature control device according to the present invention. FIG. 4 is a diagram for explaining the operation of the numerical value generator applied to the embodiment of the present invention, and FIG. 4 is a configuration diagram of a conventional temperature control device. 1... Reaction tank, 2... Heat medium, 4...
... Tank temperature detector, 7 ... Inlet temperature sensor, 8 ... Cooling water control valve, 9 ... Steam flow control valve, 12 ... ...Cooler, 13...
・Heater, 21...Jacket inlet temperature controller, 22...Target creation means, 23...Tank temperature control t1.24...Adder , 30...
... Goal creation means, 31 ... Average calculation section, 3
2... Subtraction section, 33... Absolute value calculation section, 34... Tank temperature controller, 35...
Reciprocal calculation section. Applicant's agent Patent attorney Takehiko Suzue No. 11

Claims (3)

[Claims] (1) A temperature control device in which a temperature controller generates an operation signal based on an inlet temperature signal detected at the inlet of the tank to control the temperature of the heat medium supplied to the tank, controls the internal temperature of the tank. An in-tank temperature sensor for detecting the temperature, an outlet temperature detector for detecting the temperature of the heat medium flowing out from the tank, and a deviation between the in-tank temperature signal and the setting signal from the in-tank temperature detector. 1. A temperature control device comprising: a target generating means for correcting the operation signal according to a change in the outlet temperature signal from the outlet temperature detector and outputting the corrected operation signal as a target value signal for the temperature controller. (2) The temperature control device according to claim (1), wherein the target generation means obtains the target signal by adding the outlet temperature signal to the operation signal obtained from the deviation between the tank internal temperature signal and the setting signal. (3) The target generation means obtains an average temperature signal of the outlet temperature signal and the inlet temperature signal, obtains a deviation signal between this average temperature signal and the tank internal temperature signal, and then calculates the temperature signal using the reciprocal of the deviation signal. The temperature control device according to claim 1, wherein the target signal is obtained from the bath temperature signal and the setting signal by correcting the exchange efficiency.