SU1055774A1 - Method for controlling gas supply to multiple saturator - Google Patents

Abstract

GAS SUPPLY MANAGEMENT METHOD IN A MULTI-SECTIONAL SATURATOR, which provides for determining the magnitude of the velocity mismatch change: neither the gas flow rate from a given sign. comparing the gas flow rate with its current value and adjusting the pH value depending on the comparison result, characterized in that, in order to improve the quality of the juice purification process by improving the accuracy of adjusting the pH of the juice, the gas flow rate in the first two sections of the saturator is adjusted according to the flow rate of Defekovoi juice and carbon dioxide, with a correction for the deviation from the given pH value of the juice at the outlet from the second section of the saturator and the rate of its change, the gas flow to the third section is adjusted by the rejected The actual pH of the juice is from the setpoint and the rate at which it changes at the outlet of the second section of the saturator, and the gas supply to the fourth section is adjusted by the sum of the deviation values (RON of the actual pH of the juice from the setpoint and the rates of change in the pH of the juice) .

Description

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i The invention relates to the sugar industry, in particular, to the automatic control of the process of treating defecated juice with saturation gas in a MULTIPLE-TERM CONTINENT. A known method of purification of juice, involving the determination of the difference in concentrations of carbon dioxide before and after saturation and the flow rate of the acid gas l reacted in the saturator carbon. The disadvantage of this method is the poor quality of juice cleaning. The closest in technical essence and the achieved result is the method of controlling the supply of gas to the saturator, which involves determining the magnitude of the mismatch of the rate of change of gas flow from a given value, comparing the magnitude of the flow rate, gas with its current value and adjusting the pH value depending on the result of comparing - The disadvantages of the known control method are the lack of consideration of the rate of change of gas pressure and carbon dioxide content in the saturation gas, which are disturbing parameters Significantly affect yuschimi to change pH of the juice, and consequently / quality of its CLEAR DIR ki; the lack of consideration of disturbances in the consumption of defecated juice entering the saturator /, which reduces the accuracy of maintaining the desired pH value, on which the quality of juice cleaning depends. In addition, the regulation of the gas supply by the deviation of pH from the specified value does not provide a high accuracy of pH stabilization. . The purpose of the invention is to improve the quality of the juice purification process by improving the accuracy of adjusting the pH of the juice. The goal is achieved by the fact that, according to the method, we envisage the determination of the magnitude of the mismatch of the rate of change in gas flow from a given value, the comparison of the magnitude of the gas flow with its current value and the correction of the pH value depending on the comparison result, the gas flow in the first two sections The saturator adjusts according to the ratio of the costs of defecated juice and carbon-gas, with a correction for the deviation from the given pH value of the juice at the outlet of the second section of the saturator and the efo rate of change, gas consumption in t In this section, the section is adjusted for the deviation of the actual pH of the juice from the target and the rate of its change at the outlet of the second section of the saturator, and the gas supply to the fourth section is adjusted by the sum of the deviations of the actual pH of the juice from the target and the rates of change of the pH of the juice at the outlet. sections of the saturator. . The drawing shows a device for carrying out the proposed method. The device includes a multisection saturator 1 equipped with 2-4 pH sensors with 5-7 high-resistance converters and 8-10 electropneumatic electrophoresisers, recording devices 11-13 of H size, recording recorder 14 of juice and carbon dioxide consumption, regulator 15 of juice and carbonic acid ratio gas, slit juice flow meter 16 with sensor 17, measuring diaphragm 18 with sensor 19, gas analyzer 20 with secondary device 21, unit 22 for determining carbon dioxide consumption, regulating dampers 23-25, summation units 26-28, amplifiers 29 32 and 33 of power, regulators 34 and 35, receiver 36, equipped with regulator 37 and gas relief valve 38. The method is carried out as follows. A slit flow meter 16 with a sensor 17 and a measuring diaphragm 18 with a sensor 19 measure the flow rate of the juice and the saturation gas entering the saturator. At the same time, in block 22, the flow rate of carbon dioxide is determined by the flow rate of saturation gas and the content of carbon dioxide in it, which is measured by the gas analyzer 20c with the secondary device 21. Then, the flow recorder 14 records the flow rates of juice and carbon dioxide. After that, the deviation of the actual pH value of the juice from the preset at the exit from the second section of the saturator is formed. For this, a pH recorder 11 determines the pH sock value at the outlet of the second section of the saturator, corresponding to the alkalinity of the filtered juice 0.14% CaO. The actual value is measured by a high-impedance transducer 5 with a sensor 2, the output current signal of which in the electropneumatic transducer 8 is converted into a pneumatic signal corresponding to the actual value of pp juice. Then, in block 26, the summation of the actual pH value of the juice from the set value is determined, and the rate of change of the deviation is determined in block 29 of the preliminary. The peculiarity of the latter is that the deviation generated in summation unit 26 in the steady state is repeated by the precautionary unit 29, and in the dynamics another deviation rate is also generated. The output signal of the block 29 is fed to the input

regulator 15 and after comparing and adjusting the ratio of the flow of juice and carbon dioxide in it enters the complementary mechanism of the control valve 23. Adjusting the output signal from the second sec- tion of saturation makes it possible to take into account the dynamics of the process before the third section and to achieve high accuracy of maintaining pH.

Then the recorder 12 set the pH value at the outlet of the third section of the saturator, the corresponding alkalinity of the juice is also 0.14% CaO. The actual value is measured by a high KooMHtJM converter b with a sensor 3, the output current signal of which in the electropneumatic converter 9 is converted into a pneumatic signal corresponding to the actual pH value of the juice. In the controller 34, a control signal is formed that is proportional to the magnitude of the deviation of the pH from the predetermined value and the rate of its change. Further, in block 27, this signal is corrected for the deviation of the pH of the juice at the output of the second section and its rate of change, and then amplified in the power amplifier 32 and enters the additional mechanism of the control flap 24.

To supply gas to the fourth section of the saturator with a recorder, cm 13 set the pH of the juice at the outlet of the fourth section, corresponding to alkalinity, for example, 0.11% CaO. The actual value is measured in a high-impedance converter 7 with a sensor 4, the output current signal of which in an electropneumatic converter 10 is converted into a pneumatic signal corresponding to a factor. tichesky pH value of juice. In controller 35, a control signal is formed / proportional to the value of

deviations of the pH from the target value, and the speed of its change. Further, in block 28. Summing up, when signals from blocks 30 and 31 of the alert enter it, this signal is corrected by the deviations of the pH of the juice and the rate of their changes at the outputs from the second and third sections of the saturator and, increasing in the power amplifier 33, enters the executive

0 the mechanism of the regulating valve 25. The correction of the output signal from the regulator 35 in the summation unit 28 allows to take into account the dynamics of the process before the fourth section of the saturator and to improve the accuracy of the adjustment of the pH of the juice at the outlet of the saturator.

In order to compensate for perturbations due to gas pressure, the gas pressure is stabilized by the regulator 37 and the gas relief valve 38. When connecting to the regulator nipple 37, a pressure pressure tube is connected. Head Receiver 36.

The need for more accurate maintenance of a given pH value at the outlet of the saturator is determined by the technological regulations of the process. Thus, significant deviations in the pH of the juice in the direction of increase during transient processes lead to penia of the juice and deterioration of its filtration properties, while deviations of the pH of the juice in the direction of lower pH lead

5 to the increase of its chromaticity due to the peptization of a part of nesahars. Gradual. lowering the pH of the juice with a given technological regulation provides for obtaining a fine powder 0 with increased alkalinity, which has a greater adsorptive capacity, which will lead to more complete removal of non-sugars and improvement in the quality of the purified juice.

Claims (1)

METHOD FOR MANAGING GAS SUPPLY TO A MULTI-SECTION SATUATOR, which provides for determining the mismatch of the rate of change of gas flow from a given value, comparing the gas flow rate with its current value and adjusting the pH value depending on the comparison result, characterized in that, in order to improve the quality of the juice purification process by increasing the accuracy of regulating the pH of the juice, the gas flow rate in the first two sections of the saturator is regulated by the ratio of the flow rates of the defecated juice and carbon dioxide, with correction for the deviation from the set pH value of the juice at the outlet of the second section of the saturator and the rate of change, the gas flow rate in the third section is adjusted by the deviation of the actual pH of the juice from the set value and the rate of its change at the outlet of the second section of the saturator, and the gas supply to the fourth section is adjusted by the sum of deviations ^{of the} actual pH of the juice from the given and the rate of change of the pH of the juice at the outlet of the second and third sections of the saturator.