SU1002296A1 - Device for automatically controlling synthesis of ethylethoxy silanes - Google Patents

Description

The invention relates to devices for automatic control of the temperature-time program for the synthesis of ethyl xysilanes and can be used in the automation of the production of polydiethylphenylsilksanes and lacquers based on them and other products in the chemical industry. The synthesis of ethylethoxysilanes is one of the main stages in the production of polydiethylphenylsiloxane varnishes. Ethylztoxysilanes are synthesized in steel-equipped reactors equipped with a steam jacket and an agitator. Magnesium in the form of chips is loaded into the reactor, and, supplying steam to the jacket, the apparatus is heated to 30-50 C. A little reaction mixture (toluene, ethyl chloride and ethyl ether) is fed into the reactor from the metering device to trigger the reaction. Because of the heat generated by the exothermicity of the reaction, the temperature of the reaction mass rises to 80 ° C, which indicates the start of the reaction. To lower the temperature of the reaction mixture, the water supply system of the main line is fed into the jacket of the reactor and, at the same time, the reaction mixture from the dosing mernik. The desired synthesis temperature is controlled by the speed at which the reaction mixture is introduced and the intensity of cooling with water supplied to the jacket. After the entire reaction mixture has been introduced, the mass in the reactor is gradually C heated in steam for 2-3 hours and fed to the jacket of the apparatus and maintained for 2-3 hours while operating the stirrer. The resulting mixture of ethyl ethoxysilanes (ethyl paste) is cooled with water supplied reactor jacket. The operation of the synthesis of ethylethoxysilanes is completed. The regulation of the process of synthesis of ethyl ethoxysilanes is currently carried out manually, which requires close attention and high qualification of the operator, and in real conditions of production inevitably leads to a decrease in the accuracy of parameters maintenance, lengthening the cycle of the synthesis process, to a violation of the required characteristics of the prepared product. A device for automatic control of a dimethyldioxane synthesis reactor is known, which contains a temperature controller for the hydrogen-hydrated fraction, the output of which is connected to a valve on the steam supply line to the heat exchanger, and the inlet is connected to a hydrocarbon fraction temperature sensor, a temperature controller in the reference element reactor, a relay element the insensitivity zone, the input of which is connected to the temperature sensors of the hydrocarbon fraction, and the output to the control input of the logic unit connected to the output from the control unit ohm condensate t.emperatury via series connected nye integrator and an adder, and an input - a comparing element regulator reactor temperature connected to temperature controller torus hydrocarbon fraction EI. This device does not provide high quality output product. It is also known a device for the automatic control of the synthesis process, for example, lacquer resins in a reactor with the input of the reaction mixture from the metering device, containing a temperature controller connected to the input variable with a temperature sensor of the reaction mixture in the reactor, and with a task input — with a software setpoint for temperature, an actuator on the coolant supply line to the reactor jacket and a correction unit t 3 The correction unit in a known device The unit is designed to automatically change the settings for temperature control depending on the part of the temperature-time synthesis program. Studies of the transient characteristics of the synthesis of ethyl ethoxysilanes have shown that the selected optimal settings of the temperature controller provide the required quality of the control process for all parts of the temperature-time program. Therefore, for the conditions of the synthesis of ethyltoxy silanes, the need for a unit that adjusts the temperature regulator in time is no longer necessary. The disadvantage of this device is that it does not provide high quality control of the temperature conditions of the process, which leads to higher energy costs and unproductive losses of raw materials and products. This is due both to the nature of the time-temperature synthesis program, and the need to automatically control and switch the reaction mixture into the reactor, the energy flow of steam, water, condensate, the upper and lower drain. At various stages of the synthesis of ethyl ethoxysilanes, the temperature regime in the reactor must be controlled by varying the supply of the reaction mixture, cooling water or coolant, which is also not realized in the known device. In addition, the known device does not provide consistent regulation of the level and pressure in the metering unit with the synthesis process in the reactor. The aim of the present invention is to improve the quality of the product obtained, to reduce energy consumption and unproductive losses of raw materials and products due to an increase in the quality of temperature control. This goal is achieved by the fact that a known device containing a temperature controller associated with the inlet is variable with the temperature sensor of the reaction mixture in the reactor, and the task input is with a programmed temperature setter, an actuator on the coolant supply line is additionally introduced with a level indicator in the metering unit, the command unit, the positional temperature controller of the reaction mixture in the reactor, relays, triggers, comparison elements AND, starter, actuators on the azo lines the air into the metering unit, the reaction mixture into the reactor, the cooling water into the reactor jacket, the condensate, the upper and lower drains from the reactor jacket, while the output of the level gauge in the metering unit is connected to the first input of the first trigger, to the first input of the first element And, with the actuators on the lines of nitrogen and air in the metering unit, the second input of the first trigger is connected to the first input of the second comparison element AND and the output of the actuator, and the output of the first trigger is connected to the first input of the first relay, the second input the first relay is connected to the output of the temperature controller, the second input of the second comparison element I and the first input of the command unit, and the output of the first relay is connected to the actuator on the supply line of the reaction mixture to the reactor, the second input of the first comparison element I connected with the input of the program setting unit - / temperature, with the input of the second relay and the output of the second trigger, and the output of the first comparison element I is connected to the second input of the command block, the output of the second comparison element and connected to the first input of the second trigger and the third input of the command block, the second input of the second trigger connected to the output of the third element of the comparison And, the output of this expensive relay is connected to the first input of the third relay, the first input of the third element of the comparison And is connected to the input setting of the temperature controller and the output of the software The first setpoint, the second input of the third element of the comparison I is connected with the second input of the third relay and the output of the positional temperature controller, the input of the positional temperature controller is connected to the temperature sensor of the reaction mixture in the reactor, the output of the command unit is connected to the heat carrier lines in the jacket reactor, condensate, upper and lower drains from the reactor jacket, as well as with the third input of the third relay, the output of the third relay is connected to the actuator on the coolant supply line water in the reactor tube. Figure 1 presents the block diagram of the device; Fig. 2 is a diagram of the temporal-time program for the synthesis of ethyl ethoxyanes and a sequence diagram of the operation of the actuators. In the reactor 1, the reaction mixture comes from the mernik-metering device 2 through the flow meter 3. The device contains a sensor 4 of the temperature of the reaction mixture in the reactor 1, a level 5 signaling device, command, ny. block 6, temperature controller 7, temperature programmable temperature adjuster 8, position controller 9 of relay temperature 10-12, triggers 13 and 14, elements 1 17 of the comparison H, starter 18, actuators 19-26, installed respectively on the nitrogen lines, air, reaction mixture, heat carrier, upper drain, cooling water, condensate, and lower drain. In Figure 2, a diagram of the temperature schedule for the synthesis of ethyl ethoxy silanes shows how the temperature of the reactor varies with the herd process. It follows from the diagram that raising the temperature in the reactor prior to the start of the reaction and unloading the reducer is carried out with manual control, and the temperature is reduced, its control is introduced into the automatic mode when the reaction mixture is preheated, held and deposited. The sequence diagram of the operation of the actuators shows the order and du of their inclusion at various stages of the synthesis process. The shaded part indicates that the appropriate process or power line is open. At the beginning of the process operation, the dipstick 2 is filled with the reaction mixture. The output signal of the 5 level detector goes to the actuators 19 and 20 installed in the nitrogen and air lines into the metering unit 2. At the same time, the nitrogen enters the meter doser, creating a pressure head of 0.7 MPa in it, and overlaps the line air, i.e. a line connecting the bore of the dipstick with the atmosphere. The initial stage of the process is pg, reaction call (raising the temperature to 110 ° C by supplying the reaction mixture is carried out manually by the operator at a place or remotely from the instrumentation and automation. When the call for the reaction occurs, the device is started for automatic temperature-time control Ethyl ethoxysilanes synthesis program. The device works as follows. When the actuator 18 is pressed, the signal goes to the AND element 16 and the trigger 13. To the second input, an EleieHTa 16 comparison signal and the signal stunts from the temperature controller 7 only if the temperature in the reactor is at least 110 ° C. If there are two signals from the starter 18 and controller 7, the signal 1 is output from the output element 16 of the comparison And, which is fed to the command unit 6 including it and trigger 14, setting it in a position where signal 1 is generated at its output, trigger output signal 14 is fed to relay 11, which sends a signal through relay 12 to actuator 24, which opens cooling water supply to reactor jacket} on software 8 adatchik temperature, including it in the comparison member 15 and, thus preparing circuit povtornogo.vklyucheni command unit 6 .. The signal outputted from. the actuator 18 to the trigger 13 generates the O signal at its output. The output signal of the trigger 13 goes to the relay 10 and sets it to the state where the output of the temperature regulator 7 goes to the actuator Mechanism 21 installed on the supply line the reaction mixture into the reactor 1. Thus, the temperature control loop by the feed of the reaction mixture is included. Simultaneous activation of the software setpoint 8 and the automatic temperature control circuit is necessary to improve the quality of regulation and eliminate the false actuation of the actuator 21. When the temperature of the reaction mixture in reactor 1 decreases from 110 to 70 ° C, the command unit 6 is turned off, and the temperature controller 7 receives a signal the constant task from software z-adatchika 8, i.e. The stage of entering the reaction mixture has begun. When the temperature in the reactor is below 65 ° C, 4VO is possible at the end of the stage of entering the reaction mixture due to the reactivity of the mass, at the outlet

position regulator 9 (/ tuned to signal 1, which is fed to relay 12 and interrupts the signal from relay 11 to actuator 24. At the same time, actuator 24 draws cooling water to reactor jacket 1.

When emptying, the measuring device-metering 2 triggers the 5 level detector and its output signal goes to the comparison element 15. And, which, if there is a signal 1 from the trigger 14, generates a signal 1 at the output. and re-enables the command block b on the trigger. 13, generates a signal 1 at its output, which is fed to the relay 10 and puts it into a state when the signal from the output of the regulator 7 to the actuator 21 is cut off and the latter overlaps the reaction mixture supply line to reactor 1; to actuators-mechanisms 19 and 20, which, respectively, cut off the flow of nitrogen into the dipstick 2 and connect its cavity with the atmosphere,

Further control of the process is carried out by commands from the command block b by acting on the actuators in accordance with the cyclogram shown in FIG. 2. At the stage of heating the reactor 1 in accordance with the bad program, unit 6 connects the output of temperature controller 7 to the actuator 22 installed on the supply line of the coolant in the jacket of the reactor 1, i.e. at this stage: the regulation of the temperature of the reaction mixture in the reactor is carried out according to the program from the setpoint 8 by supplying a heat carrier,

At the end of the reactor preheating stage, the signals from the command block b, the actuators 22 and 25, shut down the steam and condensate supply lines. In the temperature holding stage, the heated reaction mass is held for 2 hours without steam and cooling water. At this stage, in accordance with the sequence diagram of the actuators (figure 2), the signals from the command block b, the actuators 23 and 26 open the lines of the upper and lower drain. Kdn-f sat is drained to the jacket of reactor 1, after which the actuator 26 overlaps the bottom drain line ..

At the end of the temperification stage, the command unit 6 is through. Relay 12 outputs a signal to the executive mechanism 24 to open the cooling water supply to the reactor jacket. The cooling stage has begun. The command unit 6 is turned off. By reducing the temperature in the reactor below

The control regulator 9 generates a signal H to the relay 12, which closes the signal going to the actuator 24. In this case, the actuator closes the cooling water supply to the jacket of the reactor 1; on the comparison element 17, And.., which already received a signal from the program setting device 8, At the output of the comparison element 17, a signal appears that arrives at the trigger 14 and generates an output signal at its output. In this case, the relay 11 returns to its initial state , t, e, the signal for opening the cooling water supply is blocked, and the program control unit 8 is turned off. When the setting device 8 is disconnected, the signal from the temperature controller 7 is removed, at the output of which a signal equal to Susan zero is formed, at which the actuator 21 blocks the reaction mixture supply line. The synthesis of ethylethoxysilanes is completed. The control device is in the initial state and is ready, after unloading the reactor 1, for the next operation.

The use of this device for automatic control, temperature-time, of the program for the synthesis of ethylacisilanes provides, in comparison with existing devices, a higher quality of process control and, as a result:

-improves the quality of the product;

- reduces energy consumption for the synthesis process;

-reduces the loss of s.yr and finished product.

Claims (1)

Invention Formula A device for automatically regulating the synthesis process / ethylethoxysilanes in a reactor with the input of the reaction mixture from the metering device containing a temperature controller connected to the input is variable with the temperature sensor of the reaction mixture in the reactor, and the input of the task with a program setpoint temperature actuator on the supply line the heat carrier in the jacket of the reactor, characterized in that, in order to improve the quality of the product obtained, to reduce energy consumption and unproductive losses of raw materials and product due to improving the quality of the temperature control mode, it additionally contains a level indicator in the measurer, the control unit, the position regulator of the temperature of the reaction mixture in the reactor, the relay. triggers, elements of comparison And, starter, actuators on the lines of nitrogen and air in the metering unit, the reaction mixture in the reactor, cooling water in the jacket of the reactor, condensate, upper and lower flaring from the jacket of the reactor, the metering device is connected to the first input of the first trigger, to the first input of the first element of comparison I, with actuators on the lines of nitrogen and air in the measuring device, the second input of the perBo: Po trigger connected to the first input of the second element of comparison And you the actuator travel, and the output of the first trigger is connected to the first input of the first relay, the second input of the first relay is connected to the output of the temperature controller, the second input of the second comparison element I and the first input of the command block, and the output of the first relay is connected to the actuator on the reaction supply line in the reactor, the second input of the first element of the comparison And. connected to the input of the programmable temperature setting device, to the input of the second relay and the output of the second trigger, and the output of the first comparison element I is connected to the second input of the command unit, the output of the second comparison element I is connected to the first input of the second trigger and the third input of the command unit, the second input of the second trigger connected to the output of the third EE element of the comparison And, the output of the second relay is connected to the first input of the third relay, the first input of the third element of the comparison And is connected to the input setting of the temperature controller and the output of the prog the frame input, the second input of the third comparison element I is connected to the second input of the third relay and the output of the positional temperature controller, the input of the positional temperature controller is connected to the reaction temperature sensor in the reactor, the output of the command unit is connected to the reactor lines on the coolant lines , condensate, upper and lower drains from the reactor jacket, as well as with the third input of the third relay, the output of the third relay is connected to the actuator on the cooling supply line kvdey water in the jacket of the reactor. Sources of information taken into account in the examination 1, USSR Author's Certificate No. 409726, cl. 01 J 1/00, 1974. 2, Manusov E. B. Control and regulation of technological processes of paint and varnish production, M, Himi, 1977, p. 50. Ti gNlAzot Air Reaction JL2 / mixtures rv carrier PG p «SI Condensate Xh« ej-t} Lower c / bend 26 II fJ /four {five // /five 18