SU542544A1 - Method for automatic protection of chemical processes - Google Patents

Description

one

The invention relates to the field of chemical technology and can be used in systems for automatic protection of potentially hazardous processes.

There is a known method of automatically protecting a chemical process by generating warning signals for the flow and pressure of gaseous products with a correction in the power consumed by the motor of the agitator.

1 There is a known method for automatically protecting a chemical process by generating warning signals based on the rate of change in temperature of the reaction mass, flow rate and pressure of gaseous products in apparatus 2.

As a prototype, a method of automatic protection of chemical processes is adopted by forming the initial protective effects and dumping the reaction mass according to the temperature of the gas phase 3.

However, when the process enters an emergency mode as a result of intense gas evolution, the gas phase temperature changes much slower than the level of foamed reaction mass increases, therefore the protection system for the gas phase temperature is more inertial and gives a control signal with a large delay.

2

In order to increase the speed and eliminate the false triggering of the protection system according to the proposed method, the initial protective effects are generated by the difference in temperature between the sensor located at the initial m dangerous level of the foam layer of the reaction mass in the apparatus and the sensor located in the gas phase, and reset

carried out by the value of the temperature difference between the sensor located at the maximum allowable level of the foam layer of the reaction mass in the apparatus, and the sensor located in the gas phase, with a reset signal given after the initial protection signal.

A schematic diagram is provided in the outline, illustrating the method of protection. The method is carried out as follows.

zom. As a result of the gassing in emergency mode, the reaction mass in the reactor 1 rises, its level rises and reaches the temperature sensor 2, which fixes the lower dangerous mass level. Sensor 2

transitions from the gas phase to the foam layer of the reaction mass and, due to the change in heat transfer conditions, signals appear between the sensor 3 temperature in the gas phase and the temperature sensor 2,

included in the differential circuit.

By the value of the temperature difference, the functional unit 4 forms the initial protective effects: on the cut-off of the dosage of the reagent with the help of the valve 5, on the non-switching of the heating mode to the cooling mode using the valves 6, 7 to supply the coolant, 8, 9, for the addition of the refrigerant to intensify the stirring of the agitator with using the drive 10. At the same time, the signal from the functional unit 4 warns of possible clogging of the flow from the reactor 1.

If the level of the foaming response mass reaches the temperature sensor of the maximum allowable level 11, then the difference between the signals occurring between sensors 11 and 3, the functional unit 12 generates a control signal for opening the valve 13 from the reactor.

In order to prevent false triggering of the protection system, it is carried out to prevent accidental discharge of the reaction mass with the logic block 14, which blocks the functional block 12 from accidental triggering. And only on the signal of the initial protection the logical block removes the “Prohibition on reset.

Claims (3)

1. Author's certificate of the USSR 306868, cl. At 01J 3/00, 1970 2. USSR author's certificate Luo 340443, cl. BG1J 3/00, 1967 3. Authors certificate of the USSR LGD 339308, cl. At 01J 3/00, 1970 S 6