SU1217789A1 - Method of automatic control for process of industrial waste water neutralization - Google Patents

Description

The invention relates to the treatment of wastewater in the production of ammophos and can be used on co-reagent industrial effluents, contaminated with compounds of phosphorus salts, in the chemical, metallurgical and energy sectors.

The drawing shows a diagram of the device that implements the method.

The device contains a mixer-reactor 1, regulator 2 for stabilizing the pH value of purified water, regulator 3 for stabilizing the consumption of reagent, regulator 4 for stabilizing the ratio of reagent consumption: air flow, regulator 5 for stabilizing the water level in the neutralizer, regulator 6 for stabilizing the consumption of purified water , sensors: 7 flow, 8 pH values, 9 concentrations, 10 F concentrations of purified water; Sensors: II flow, 12 electro. water content, 13 pH values, 14 temperatures, 15 densities, 16 concentrations P.) 5, 17 F concentrations, 18 SO concentrations of the water to be purified; sensors: 19 lime milk concentration, 20 lime lime consumption at the reactor inlet; sensors Kif: 21 reactor water levels, 22 air flow rates; drawing unit 23, which contains a modeling block 24, a block 24 model model coefficient correction 25 block, a block 26 for outputting optimal parameters to the controllers and a block 27 for parameter constraints.

The method is carried out as follows.

Purified water is mixed with the milk of lime by bubbling the air in reactor 1. Purified water is sent to a sump. In the neutralization process, the pH of the purified water is maintained in a predetermined range by regulator 2 by changing the supply of milk of lime reagent along the bypass line. The flow rate of the reactant at the reactor inlet is measured by the baseline by the sensor 20 and is controlled by the controller 3 by changing the flow rate of the reactant. Reagent consumption and air consumption are measured by sensors 20 and 22, and their ratio is controlled by regulator 4 by changing the air supply. The water level in the neutralizer is measured

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sensor 21 and regulate the controller 5 by changing the flow rate of purified water. The inlet flow of purified water is measured by sensor 11 and is controlled by regulator 6 by changing the supply of purified water. In block 24, the simulation of the computing device 23 has a controllable process model in the form

101

 (., X, X2, X j, X c, X, X, Xg,

 l-

(one)

IS

 (, X, X2, X J, Xj, X, X, X,

Ha, hd, x. , X, X);

(2)

Yj-f (x x xj x, xg x x.,

XjXg X)

(3)

Y - Y. 3

where ,, aj; - coefficients of the equation (I) - (.3);

X - - input parameters

process, measured by sensors 11-22, respectively; - output process parameters measured by sensors 8-10, respectively.

For optimal control of the process, an optimality criterion was chosen, which consists in minimizing the sum of concentrations and F in purified water, i.e.

35

 Y, + Y,

nin.

if there are bilateral restrictions on the pH value of purified water, i.e.

18 top 1 1NIL;

In addition, there are similar two-sided restrictions on such input parameters as X ,, X,

X., and, this criterion allows

Based on the equations (1) - (3) and constraints on Y, X, X, X, X to find the minimum possible value of Y, j is UZ and, accordingly, the optimal values of Y, X, X, X and. Restrictions on the parameters are enclosed in block 27.

In block 26, the optimal values are determined based on the optality criterion for the current values of the parameters measured by the sensors 12–19, and taking into account the two-sided technological limitations inherent in block 27,.

on the parameters Y, X ,, X ,, X, X., according to equations (1) - (3) of the neutralization process based on the scanning algorithm, the optimum values of the parameters are developed for issuing tasks to the regulators 2-6.

In connection with the non-stationarity of the neutralization process after a predetermined period of time (2 hours) in the correction unit 25 for current values received from the sensors. 7-10, 21, 11-20 and 22, according to the well-known algorithm, periodic corrections are made3 |

coefficient of a

i; -2i

the process is nitra-

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equations SP - (3 lizatsii.

After adjusting the coefficients of equations (1) - (3) of the neutralization process in block 26, a new recalculation of the optimal values of the parameters for issuing tasks to the regulators 2, 3, A and 6 is performed.

Thus, ensuring a minimum of the criterion of optimality in block 25 makes it possible to ensure the minimum value of the concentrations and F c. purified water and thereby increase the efficiency of the neutralization process.

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Editor A.Dolinich

Compiled by A.Popov Tehred S.Migunova

Order 1070/26 Circulation 865 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, st. Project, 4

Proofreader E. Sirohman

Claims (1)

METHOD FOR AUTOMATIC CONTROL OF THE NEUTRALIZATION PROCESS OF PRO · 'INDUSTRIAL WASTE WATERS, including measuring the pH flow rate, conductivity of the treated water, the pH of the purified water, stabilizing the pH of the purified water by changing the flow of lime milk along the bypass line, that, in order to optimize the neutralization process by increasing the reliability of control, additionally measure the temperature, density and concentration of P _g 0 ^, F, SO _{3 of} purified water, the flow rate and concentration of P _x 0 ₅ and F ^- purified water, the flow rate and concentration of lime milk, air flow for bubbling, the water level in the neutralizer, the optimality criterion is calculated using the measured parameters, which is used as the minimum value of the sum of the concentrations of P ₂ 0 ₅ and F in the purified water, the flow rate of purified water and the flow of milk of lime are stabilized by changing their flow rate, · Water level g in the converter by changing the flow rate of purified water, the ratio of the flow of milk of lime - air flow rate for bubbling by changing the flow rate of air, while the task is to measure the flow rate of the cleaned water and milk of lime, the water level in the neutralizer, the ratio of the flow rate of milk of lime - air consumption for sparging, pH, purified water is determined by the criterion of optimality.