Method of control over the process of decomposition of the aluminate solution in the alum earth production |
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IPC classes for russian patent Method of control over the process of decomposition of the aluminate solution in the alum earth production (RU 2310607):
    
 Method for moisture stabilization of dairy butter / 2302108
Continuous action butter machine includes seasoning reservoirs, churning machine with mixer and normalizing component batching pump. At outlet of continuous action butter machine, value of expected butter moisture deviation is determined from a formula. Churning machine mixer rotation frequency is controlled together with feeding of normalizing component depending on deviation of moisture from given value with consideration of value of expected component.
 Method for stabilizing of butter moisture normalization process / 2298918
Method involves regulating rotational frequency of churn mixer and feeding normalizing component depending on butter moisture content deviation from predetermined value; changing cream churning temperature depending on changing of butter moisture content deviation from predetermined value. When butter moisture content is below predetermined value, cream temperature is changed by value equivalent to normalizing component dosing value. When butter moisture content is above predetermined value, cream temperature is changed by value equivalent to butter moisture content deviation from predetermined value. Method allows butter yield to be increased to more than 180 kg per working shift.
 Device for remote controlling of parameters of industrial area / 2279704
Device can be used for inspection and control and levels of physical factors of industrial area. Device has control unit, signal converters, temperature detector, noise detector and illumination detector, illumination and noise signal converters for any detector, maximal and minimal temperature presetting devices. Device also has ultimate level noise level set-point device, ultimate limiting illumination level set-point device, comparator for any measured parameters ultimate values set-point device (as temperature, noise and illumination level), logic gates for any factor to be controlled, permanent memory unit, temperature, noise and illumination values counters and oscillator.
 Process for automatic control of sugar clarification and automatic control system for performing the same / 2267149
Method for automatic control of clarification of sugar by means of sugar-containing solution in successively joined auger and horizontal sectional clarifying agitator at supplying sugar to auger comprises steps of controlling flow rate of sugar-containing solution to clarifying agitator depending upon concentration of dry matters in clarified product; supplying to auger catholyte with pH 10 - 11.5 and feeding to first section of clarifying agitator milk of lime; controlling flow rate of catholyte in such a way that in those section of clarifying agitator where clarifying process is going on for 4 - 6 min concentration of dry matters is in range 12 -18% and controlling flow rate of milk of lime in such a way that pH in the same section is in range 10.8 - 11.5; supplying sugar- containing solution to next sections of clarifying agitator along motion direction of sugar in it; measuring concentration of dry matters in order to control flow rate of sugar-containing solution in last section of clarifying agitator. Automatic control system for controlling clarification of sugar in successively joined auger and horizontal sectional agitator includes circuit for stabilizing concentration of dry matters of clarified product with use of pickup for measuring concentration of dry matters. Auger is provided with branch pipes for feeding catholyte into it. Clarifying agitator includes branch pipe for feeding lime of milk to first section. Pickup for measuring concentration of dry matters is arranged in last section of clarifying agitator. System includes in addition circuit for controlling quality of clarification having pickups for measuring pH and concentration of dry matters, both placed in one section of clarifying agitator and pickup for measuring catholyte flow rate; regulators and valves. One valve is mounted inline for feeding milk of lime and other valve is mounted inline for feeding catholyte.
 Method for automatic control of sugar liquoring process and system for automatic control of realization of this method / 2260832
Method for automatic controlling of sugar liquoring process in horizontal sectional liquoring continuous-action mixer and accumulating mixer includes changing flow of liquoring solution with consideration of liquoring concentration in accumulating mixer. Into sections, where concentration of dry substances does not exceed 18%, lime milk is fed, flow of which is adjusted so, that pH of liquoring in this sections was 10,8-11,2, and stop of sugar feeding into liquoring mixer is performed when liquoring level in accumulating mixer reaches certain level. System for automatic control of sugar liquoring process in horizontal sectional liquoring continuous-action mixer and accumulating mixer includes level sensor in accumulating mixer, mounted in said mixer, liquoring concentration sensor and liquoring solution feeding adjuster into first section of liquoring mixer. Each section of liquoring mixer, except last one, is provided with branch pipe for feeding lime milk, pH indicator and dry substances concentration indicator. Also, system is provided with serially connected valve for stopping sugar feed into liquoring mixer and adjuster, input of which is connected to level indicator, mounted in accumulating mixer, while the latter is connected to liquoring solution feeding adjuster into first section via set-point device, connected to concentration sensor. Use of device allows to increase efficiency of sugar purification due to forming of favorable conditions for decomposition of reducing substances during liquoring. Containment level of reducing substances in sugar liquoring is decreased in 1,4-1,4 times.
 Control method for high-viscous oil product discharge from railroad tank cars / 2257327
Method involves determining temperature of outer tank car wall by measuring thereof in lower tank car case portion, which is the nearest to tank car bottom; comparing the measured temperature with one estimated from heat calculations performed with the use of control computer. The temperature is calculated from well-known correlations with taking into consideration previously measured temperature of ambient air and wind velocity, technical characteristics of tank cars, physical properties of oil product to be discharged and air.
Method of automatically governing biotechnological process / 2248399
Invention concerns governing periodical air-intake biotechnological process carried out in bioreactor. Method comprises measuring oxygen content in effluent gas, working volume of culture medium, concentration of biomass, and concentration of intermediate product of its vital activity. Measured parameters allow specific oxygen consumption rate and velocity of intermediate product concentration change to be determined to enable regulation of feeding air used in aeration, supplying nutritional medium, and agitating culture medium. Moreover, temperature of culture medium, temperature of supplied and withdrawn cooling agent, and consumption of the latter are measured to use these parameters for determining biomass heat release rate and velocity of intermediate product amount change. The two latter parameters enable regulation of feeding air used in aeration and supplying nutritional medium. The following characteristics are thus improved: elevating power by 8.1%, maltase activity by 7.9% and resistance by 7.4%.
 Method for automatic controlling of continuous malting process / 2248390
Method involves providing continuous malting process in rotating drum; measuring and stabilizing temperature of malt by changing air flow rate for cooling of grain under germination procedure; additionally measuring malt moisture content and regulating it depending on changing of malt moisture content as compared to set values by changing water supply for grain moistening during germination process; also, regulating water supply for cooling air and correcting changing of air flow rate for cooling of grain under germination process depending on changed temperature of malt as compared to set values.
 Method for automatic humidity control in the production process of cheese / 2231106
The invention relates to the dairy industry, in particular to the management of production of cottage cheese
 Method for bauxite reprocessing / 2267462
Bayer method for alumina production from bauxite includes bauxite breakage, wet milling in presence of reversible solution obtained after mother liquor boiling down, dilution of leached pulp, thickening, filtration, decomposition of aluminate solution to isolate aluminum hydroxide and to produce mother liquor, aluminum hydroxide calcination to produce alumina, and non-operative decomposer cleaning by precipitate washing with alkali solution. Part of mother liquor is boiled down up to concentration of 220-260 g/l Na2O3 and fed in decomposition step into non-operative decomposers to cleaning thereof from aluminum hydroxide precipitate. After cleaning process solution is decomposed in operative decomposers.
 Method of deposition and classification of aluminum hydroxide / 2263635
Proposed method includes delivery of supersaturated aluminate solution into cooling loops by two flows; lesser flow is delivered to agglomeration stage and larger flow is directed to two crystal growth stages; after agglomeration stage, pulp is combined with part of larger flow directed to first crystal growth stage. After each crystal growth stage, pulp is subjected to classification; after first crystal growth stage, three stages of classification are performed for obtaining unloading flows. Finely-dispersed particles obtained in discharge of third classification stage are directed for agglomeration. After second crystal growth stage, classification is performed in one stage at obtaining production aluminum hydroxide; unloading flows obtained after each stage of three-stage classification performed after first stage of growth are used for seeding at two growth stages; granulometric composition of production hydroxide thus obtained is controlled by partial redistribution of unloading flows of classifiers. Proposed method makes it possible to increase size of aluminum hydroxide without reduction of deposition loop productivity and to reduce production floor at agglomeration and classification stages.
 Method for separating aluminum hydroxide out of solution / 2256616
Method comprises steps of hydraulic separation of hydroxide pulp for producing discharged products containing fine fraction of hydroxide and condensed hydroxide containing large fraction; condensation of discharged products; transporting condensed hydroxide after its hydraulic separation to one agitator, then to filtration and transporting hydroxide after condensation of discharged products to other agitator, then to filtration and repulping.
 Aluminum hydroxide classification method / 2255044
Method comprises two-step separation of hydrate suspension in centrifugal field of hydrocyclones to give, as bottom product, "sand-type" hydroxide with content of -4 mcm fractions at most 10%. First-step hydrocyclone discharge is passed to second classification step and second-step classification is effected in hydrocyclones with diameter equal to 0.4-0.7 that of the first-step hydrocyclone. Hydrate suspension is preliminarily diluted with clarified solution or water to content of solids 250 g/l.
 Method decomposition / 2231497
The invention relates to the production of alumina, namely the process of decomposition
 Installation for carbonization aluminate solutions / 2230030
The invention relates to the production of alumina from nepheline treatment or low-grade bauxite in processes where decomposition of the aluminate solutions by carbonization combustion gases containing carbon dioxide
 The apparatus for carbonization of aluminate solutions / 2226175
The invention relates to the production of alumina by the method of decomposition of the aluminate solutions by treatment of gases containing carbon dioxide
 A method of processing aluminate solutions / 2200706
The invention relates to the field of hydrometallurgical technology industries, in particular the production of alumina by the method of sintering
 Method for processing of aluminium-containing raw materials / 2197429
The invention relates to the processing of aluminium-containing raw materials by the method of sintering and can be used to obtain aluminum hydroxide pseudoboehmite patterns
 A method of processing aluminate solution in the production of alumina from nepheline / 2184703
The invention relates to the production of alumina sintering method, in particular the production of alumina from nepheline raw materials
Aluminum hydroxide classification method / 2255044
Method comprises two-step separation of hydrate suspension in centrifugal field of hydrocyclones to give, as bottom product, "sand-type" hydroxide with content of -4 mcm fractions at most 10%. First-step hydrocyclone discharge is passed to second classification step and second-step classification is effected in hydrocyclones with diameter equal to 0.4-0.7 that of the first-step hydrocyclone. Hydrate suspension is preliminarily diluted with clarified solution or water to content of solids 250 g/l.
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FIELD: nonferrous metallurgy industry; methods to control the process of decomposition of the aluminate solutions. SUBSTANCE: the invention is pertaining to the field of nonferrous metallurgy and may be used to control the inertia processes, the outlet parameter of which is nonlinearly, predominantly extremely, linked with the inlet parameters. The method to control the process of decomposition of the aluminate solution in production of the alum earth exercised in the battery of the sequentially connected apparatuses- decomposers supplied with the devices of cooling of the source aluminate solution and the decomposing pulp, the devices of separation of the decomposing pulp at the battery outlet into the large-sized production fraction and small-sized fraction in compliance with the dimension of the solid particles in the pulp, with feeding of the source aluminate solution into the head decomposer, and the small-sized fraction and the part pf the large-sized fraction - in the capacity of the streams of the seed - in the decomposers of the head part of the battery provides for measurements of the consumption of the aluminate solution inlet stream, measurement of the consumption of the seed stream, the temperature of the aluminate solution and the pulp, contents of the aluminum oxide and the caustic alkali in the aluminate solution, contents of the particles of the preset class in the commercial hydroxide, stabilization of consumption of the seeds streams, the temperature of the aluminate solution and the decomposing pulp and alterations on each step of the control of the preset stabilizing values. The preset for stabilization at each step of the control values of the consumption of the seed streams and the temperature of the inlet aluminate solution and the decomposing pulp are determined by means of the approximated mathematical model consisting of in series connected the linear dynamic link, which inlets are the measured values of all indicated parameters, and the linear static link determining the predictable value of the speed of fluctuation of the contents of the particles of the preset size in the commercial hydroxide, average and centered the measured values of all parameters, depending on which and on the predictable value of the speed of fluctuation of the contents of the particles of the preset size determine and set the given for stabilization on that step of control the values of the parameters. The invention allows to maintain the quality of the ready product - the contents of the preset fraction of aluminum hydroxide. EFFECT: the invention allows to maintain the quality of the ready product - the contents of the preset fraction of aluminum hydroxide. 2 cl, 2 dwg, 1 ex
The present invention relates to the field of non-ferrous metallurgy and can be used to control the inertial processes whose output parameter nonlinear, mainly extremely related to the input parameters. One of such processes in alumina production is the process of decomposition (decomposition) aluminate solution with separation in the solid-phase aluminum hydroxide. Apparatus and process decomposition is carried out in a battery of series-connected tank vehicles (decomposer), each of which is stirring the solution. In a separate decomposer (usually in the head phones battery) is "the seed" - a slurry containing solid particles of aluminum hydroxide, which is deposition of hydroxide from the solution. As you move the solution from the previous decomposer in subsequent decomposita pulp enriched solid phase aluminum hydroxide. After the pulp from the last decomposer solid phase is separated from the mother liquor (filtered) and is productive hydroxide supplied for further processing to obtain alumina. Part of the production of hydroxide is separated and diluted returns to the process of decomposition. This process is inertial and the residence time of the pulp in the bath the ray is 30-60 hours. In terms of decomposition of the aluminate solution, separation in the solid phase crystals of aluminum hydroxide and their growth depends on: the composition of the input aluminate solution (containing caustic alkali and dissolved aluminum hydroxide), its temperature, the quantity of seed temperature decomposing pulp, the intensity of mixing, time of the pulp in the battery decomposers. Usually to control the decomposition process is to maximize the number of productive hydroxide, in which the content of the particles are large (usually more than 40-45 MC) fraction is not less than the specified value (usually 80-90%). The specified parameter is extremely dependent on process parameters of decomposition: quantity, composition and temperature input aluminate solution, the amount of seed and temperature decomposer. There are ways to manage the process of decomposition, including the measurement and stabilization temeperatures regime and stabilization of the bare relationship - cost ratio of seed to the aluminate solution (see Handbook of metallurgy of nonferrous metals. Alumina production. Publisher metallurgy, M., 1970, s-308). Practice shows that this method does not allow production hydroxide with a given particle size, pascalc the influence of uncontrolled (or not consider) perturbations (changes in the composition of aluminate solution, the temperature fluctuations etc) lead to wavy grain size production hydroxide, and the frequency of these oscillations is 2-3 months. There are ways to manage the process of decomposition of the aluminate solution, comprising mixing aluminate solution and the seed and feed the seed suspension in the different stages of the decomposition process, measuring the flow of aluminate solution, the content of aluminum hydroxide in the seed suspension and its granulometric composition and change threads seed suspension depending on the deviation of the composition from the target value (see A.S. USSR №93029067 from 03.06.1993, A.S. No. 96124203 from 25.12.1996). The objective of such methods is to obtain production of hydroxide "sand" type (with a high content of particles of the coarse fraction). The disadvantage of these methods is poor stabilization of a given composition production hydroxide, because they do not take into account the influence of temperature on the decomposition process. A known method of controlling the decomposition process (see A.S. USSR №2051099 from 02.08.1991), according to which the aluminate solution is mixed with the seed and the resulting suspension is sent to two parallel at different temperatures of the battery, measure the granulometric composition of the aluminum hydroxide in the seed suspension and discard the Institute from the specified values change the direction of flow resulting suspension in parallel to the battery. This method also does not lead to stabilization of granulometric composition of production hydroxide. The known method for automatic regulation of the process of decomposition of aluminate solution (see A.S. USSR №1348299 from 08.08.1985), according to which stabilize caustic module in the solution decomposing pulp changing temperature, and seed ratio - changing mass flow seed hydroxide, measure the composition of the pulp at the outputs of the upper and lower levels of the last decomposer and the granulometric composition of total output stream and change the flow of the pulp from the upper level of decomposer depending on the deviation of the total composition of the output stream from the specified value. The disadvantage of this method is the need to use decomposers top and bottom unloading and the impossibility of obtaining the maximum in the specific conditions of particles of a given faction in the production hydroxide. As the prototype accepted way of managing the process of decomposition, described in the book "alumina" (Proceedings YOU No. 77, Leningrad, 1971, s-186). According to the prototype in the process of decomposition stabilize the temperature input aluminate solution and the value of the bare relationship. In this case, applying the mathematical model of the process of decomposition, op is adelayda the influence of the perturbation process (the number and composition of the input aluminate solution, temperature) on the output process indicator. As the output measure adopted caustic module decomposing pulp (the content of the aluminum hydroxide), which value should be the maximum for a given size of particles of the hydroxide. Using a mathematical model count set value temperature input aluminate solution and the value of the bare relationship. To improve the accuracy of management periodically measure the value of the output parameter (the content of the aluminum hydroxide) and adjust the coefficients of the mathematical model. This trick aims to compensate the inaccuracy of the applied mathematical model, errors of measurement (instrumentation and chemical methods of analysis), changes in the characteristics of the control object in time (covering equipment, inlay heat transfer surfaces), uncontrolled perturbations (level change in decomposer, changing conditions, mixing etc). However, as practice shows, the application of these methods can not achieve the maximum possible under specific conditions the content in the production hydroxide solids of a given composition. The objective of the invention is to maintain extreme indicator of the quality of the finished product - content ass is authorized fractions of aluminum hydroxide, that will improve technical and economic performance as process decomposition and hydrochemical cycle of alumina production. The achievement of the technical result is ensured by the fact that in the process control method of decomposition of aluminate solution in alumina production, carried out in a battery of series-connected devices - decomposers equipped with devices for cooling the source of aluminate solution and decomposing pulp, device classification decomposing pulp outlet batteries at a major production and fine fractions by size of solid particles in the pulp, with the filing of the original aluminate solution in the head decomposer, small and part of a large fraction - as thread starters in decomposer the head part of the battery, including the measurement of the flow rate of the input stream aluminate solution, the flow rate of the seed temperature aluminate solution and decomposing the pulp content of alumina and caustic alkali aluminate solution, the content of particles of a given class in the production hydroxide, stabilizing the flow of the seed temperature aluminate solution and decomposing pulp and change at each step of the control specified stabilized values determined using the mathematical model m is sa decomposition depending on the measured content of particles of a given class in the production hydroxide, set to stabilize at each step, the control value of the flow of seed and input temperature aluminate solution and decomposing pulp is determined using an approximated mathematical model consisting of a series connection of a linear dynamic link, the inputs of which are the measured values of all these parameters, and linear static link, determining the predicted value of the rate of change of the content of particles of a given size class in the production hydroxide, average and center the measured values of all parameters, depending on which and the predicted values for the rate of change of the content of particles of a given size class define and establish set to stabilize at this step, the control parameter values. When the deviation of the predicted values for the rate of change of the content of particles of a given size class in this step, control from zero by an amount equal to or more than 5% from its value at the previous step, the value of the control actions in this step, the control set in proportion to the magnitude and sign of the deviation. When the deviation of the predicted values for the rate of change of the content of particles of a given size class in this step the Board from a zero value to a value less than 5% from its value at the previous step, the amount of control actions in this step, the control set is proportional to the sign of the deviation at a constant value selected from the range of 0.5-1.0°With temperature and 5-10% from the nominal flow of the flow of the seed. Using the mathematical model, consisting of a series connection of a linear dynamic part and the static link that allows you to achieve the following objectives: - take into account the inertia of an object in linear dynamic link; - consider the extreme nature of the dependence of the output process parameter from the input parameter. Used static link is linear, predicts the rate of change of the content of particles of a given size in the production hydroxide and replaces the commonly used nonlinear static link that describes the dependence of the output parameter of the process decomposition of the input parameters (perturbations and controls). Thus, we get the mathematical model of the standard patterns in which two series-connected element is linear and for which it is possible to synthesize the optimal control algorithm, i.e. to calculate and implement at each step the optimal control when the measured parameter values (controlled perturbations and implemented controls) control actions (C the data values of temperature aluminate solution and decomposing pulp, consumption of seed), which provide the maximum possible content in the production hydroxide particles of a given size class. Based on task conditions, such control is provided by the stabilization of the predicted values for the rate of change of the contents of this class of particles (exit static link) at the zero level. Averaging and centering of the measured values of the parameters can eliminate measurement errors. The coefficients of the mathematical model is usually identified on actual decomposition process that ensures that the changes in the properties of the control object and the influence of uncontrolled disturbances. During this period of time, which is the identification, must be greater than the inertia of the process that ensures that the changes in the properties of the object per stay aluminate solution in the battery decomposers. According to another variant of the control method when the deviation of the predicted values of the parameter in this step, control from zero by an amount equal to or more than 5% from its value at the previous step, the value of the control actions in this step, the control set in proportion to the magnitude and sign of the deviation. This trick allows you to set this value in rawsumer impact, which exceeds the impact of uncontrollable perturbation parameters. Another variant of the control method when the deviation of the predicted values of the parameter in this step, control from zero to a value less than 5% from its value at the previous step, the control value of control actions in this step, the control set is proportional to the sign of the deviation at a constant value selected from the range of 0.5-1.0°With temperature and 5-10% from the nominal flow of the flow of the seed. This technique allows you to set the power control actions, which enables the estimation of the parameters of the control object. Figure 1 shows the control system, which allows to implement the proposed control methods. Aluminate solution 1 through the heat exchange device 2 enters the head decomposer 3 batteries decomposition. In the same decomposer is 4 seed. Decomposita pulp 5 through the heat exchanger 6 flows into the tail decomposer 7 batteries decomposition, and then classified in the classifier 8. A large fraction of production hydroxide through a distribution tank 9 is supplied to further processing. Part of a large fraction 10 together with a small fraction of hydroxide 11 served in head is decomposer battery as seed. To measure the costs of aluminate solution (block 12) and the seed (block 13) can be applied electromagnetic flowmeters, for example, type IL. Temperature measurement aluminate solution (block 14) and decomposing pulp (block 15) can be performed using resistance thermometers, such as SCI. Measurement of the composition of the input aluminate solution (the content of aluminum hydroxide and caustic module) is carried out periodically by chemical methods of laboratory analysis of samples (block 16). Measurement of granulometric composition of production hydroxide (content of solids of a given size class) is periodically laboratory methods of physical analysis of samples (block 17). Regulators P1, P2, P3 are respectively the stabilizer of the set value of the flow rate of the seed temperature aluminate solution and decomposing pulp and can be implemented by any type of standard PID controllers (or program in the programmable controller, for example, of the type Simatic S-7). Consumption of seed varies regulatory body 18 (e.g., valve), and the temperature of the aluminate solution and decomposing pulp, respectively regulating valves 19 and 20 are installed in the piping of the cooling medium 21. The block 22 is a computing unit that inputs the km vtorogo filed the signals measured parameters (composition of the aluminate solution, costs aluminate solution and the seed temperature aluminate solution and decomposing pulp, the composition of production hydroxide), and the output is specified values of consumption, seed and temperature aluminate solution and decomposing pulp. In block 22 is calculated by the formulas mathematical models, as well as averaging and alignment of all measured parameters. The block 22 may be implemented by a program in the controller or a personal computer equipped with input devices and output physical or interface signals. Periodically (at each step) the estimated value of the output unit 22 receives as signal assignments to the inputs of the regulators P1, P2 and P3. Example 1 the implementation of the method The decomposition process is carried out in a battery of 12 decomposers, with a capacity of 3000 m3each. At the entrance to the battery is mounted in a water heat exchanger pipe in pipe". Between the fifth and sixth decomposers also installed a heat exchanger of the same type. At the output of the battery is installed classifier for the separation decomposing pulp fractions: small - drain classifier, "large" is the bottom product of the classifier. The input stream aluminate solution varies in the range of 640-700 m3per hour, the composition of the aluminate solution is changed in the range of 140-150 g/l content hydroxide, 1,6-1, caustic module. Temperature aluminate solution varies in the range of 60-70°and the temperature decomposing pulp is in the range of 55-60°C. the Flow rate of the seed (seed ratio) varies in the range from 1.8 to 2.1, the content of fraction >45 MK in the seed was changed in the range of 75-85%. The frequency of chemical analysis of the composition of the aluminate solution was 4 hours, the frequency of physical analysis of granulometric composition of production of Oh - 8 hours. The results of the process control system decomposition (content fraction >45 MK in the final hydrate) is shown in figure 2, where: a - the results of the work on the prototype method, actually received for the time period of 64 weeks; b - results of the proposed method of control. For clarity, the results of the proposed method were simulated under the same conditions as the work on the prototype method. As can be seen, the average increase in output production of hydroxide on the considered time interval was more than 15%. Thus the range of change in the consumption of the seed (the seed of the relationship) was 1.9 to 2.0, the range of change in temperature aluminate solution of 5°and temperature decomposing pulp 5°C. Set values changed with a frequency of 1 time per day. Averaging the measured values was carried on and the interval time of 5 hours. Adopted in the description of the concept of "nominal flow is the value of the flow, defined by technological regulation of the process of decomposition of aluminate solution in alumina production and not changing in the management process. 1. The process control method of decomposition of aluminate solution in alumina production, carried out in a battery of series-connected devices-decomposers equipped with devices for cooling the source of aluminate solution and decomposing pulp, device classification decomposing pulp outlet batteries at a major production and fine fractions by size of solid particles in the pulp, with the filing of the original aluminate solution in the head decomposer, small and part of a large fraction - as thread starters in decomposer the head part of the battery, including the measurement of the flow rate of the input stream aluminate solution, the flow rate of the seed temperature aluminate solution and decomposing pulp, the content of alumina and caustic alkali in aluminate solution, the content of particles of a given class in the production hydroxide, stabilizing the flow of the seed temperature aluminate solution and decomposing pulp and change at each step of the control specified stabilized values determined using mate is eticheskoi process model decomposition based on the measured content of particles of a given class in the production hydroxide, wherein the set to stabilize at each step, the control value of the flow of seed and input temperature aluminate solution and decomposing pulp is determined using an approximated mathematical model consisting of a series connection of a linear dynamic link, the inputs of which are the measured values of all these parameters, and linear static link, determining the predicted value of the rate of change of the content of particles of a given size class in the production hydroxide, average and center the measured values of all parameters, depending on which and the predicted values for the rate of change of the content of particles of a given size class define and establish set to stabilize at this step, the control value parameters. 2. The method according to claim 1, characterized in that when the deviation of the predicted values for the rate of change of the content of particles of a given size class in this step, control from zero by an amount equal to or more than 5% from its value at the previous step, the value of the control actions in this step, the control set in proportion to the magnitude and sign of the deviation. 3. The method according to claim 1, characterized in that when the deviation of prognoziruet the CSO value of the velocity changes in the content of particles of a given size class in this step, control from zero to a value less than 5% from its value at the previous step, the amount of control actions in this step, the control set is proportional to the sign of the deviation at a constant value selected from the range of 0.5-1.0°With temperature and 5-10% from the nominal flow of the flow of the seed.
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