Method for control of potassium chloride preparation |
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IPC classes for russian patent Method for control of potassium chloride preparation (RU 2359909):
    
 Control of process of production of loose form of powdery choline chloride from its aqueous solution / 2356907
Invention is related to automation of technological processes and may be used in automation of process of production of loose form of powdery choline chloride from its aqueous solution. In method that provides for use of crushed and fractionated dry sugar beet pulp as active adsorbent, its mixing with previously heated aqueous solution of choline chloride, and then drying in vibration dryer by superheated steam of atmospheric pressure, separation of spent superheated steam flow into the main one, sent to vibration dryer with creation of recirculation circuit, and additional one sent for reheating of choline chloride prior to its supply for mixing, the novelty is the fact that superheating of atmospheric pressure steam is done with heating steam, at that heating steam is produced by means of steam generator with electric heating elements, feed pump and safety valve, heating steam condensate produced in this process after superheating and condensate produced during heating of aqueous solution of choline chloride is taken to condensate collector, and then in mode of closed circuit is supplied in steam generator, at that flow rate of crushed and fractionated dry pulp is measured, as well as aqueous solution of choline chloride coming for mixing, flow rate and temperature of superheated steam upstream vibration dryer, choline chloride temperature before and after its heating, pressure of choline chloride after heating, temperature and humidity of mixture of crushed and fractionated dry pulp and aqueous solution of choline chloride prior to supply for drying, amplitude and frequency of oscillations in gas-distributing grid of vibration dryer, flow rate and humidity of powdery choline chloride after drying, level of condensate in steam generator and pressure of heating steam, at that flow arte of dry sugar beet pulp after fractionation is used to set flow rate of heated choline chloride coming for mixing, and flow rate and humidity of prepared mixture of crushed and fractionated dry pulp and aqueous solution of choline chloride prior to supply for drying, flow rate and humidity of powdery choline chloride after drying are used to determine amount of evaporated moisture in vibration dryer, which is used to establish flow rate of superheated steam in the main circuit of recirculation, and its temperature is established by current value of temperature of mixture of crushed and fractionated dry pulp and aqueous solution of choline chloride by setting of specified capacity of steam generator affecting power of electric heating elements, at that in case condensate level in steam generator falls below specified value, condensate is supplied from condensate collector, and when pressure of steam in steam generator reaches upper limit value, steam pressure is released through safety valve, if flow rate of mixture of crushed and fractionated dry pulp and aqueous solution of choline chloride deviates prior to supply for drying to the side of increase from specified value, at first frequency is increased, and then amplitude of oscillations in gas-distributing grid of vibration dryer, if flow rate of mixture of crushed and fractionated dry pulp and aqueous solution of choline chloride deviates to the side of reduction from specified value, at first frequency is reduced, and then amplitude of oscillations in gas-distributing grid of vibration dryer, current values of temperature and flow rate of choline chloride prior to heating are used to set flow rate of spent superheated steam in additional recirculation circuit, at that temperature of choline chloride after heating is used to set specified pressure of choline chloride at the inlet to mixer.
 Method of controlling process of sylvinite ore dissolution / 2352385
Invention relates to technique of controlling processes of sylvinite ores dissolution and can be used in production of potassium chloride by dissolution-crystallisation method. Method of controlling processes of sylvinite ores dissolution includes regulation of ore supply depending on content of useful component in input flows, measuring ready solution temperature and determining sodium chloride content in solution by calculation method. Additionally determined are density, temperature and consumption of dissolving solution, content of sodium chloride in it is determined by content of useful component, density and temperature. Ore supply is calculated according to suggested equation and calculated value is given as task to system of weigher control.
 Automated method of controlling and managing process for preparing sugar syrup mixture for crystallisation by cooling / 2342438
Proposed automated method of controlling and managing the process of preparing sugar syrup mixture for crystallisation by cooling makes provisions for regulating the volumetric discharge of water entering the mixer and the level of sugar syrup in it. Regulating the level of the sugar syrup in the vertical mould is achieved by acting on the adjustable-frequency electric drive of the sugar syrup pump. Periodically using the lab the density of the ready sugar syrup is controlled at the exit from the mixer. The active electrical power which is used in the electric motor of the sugar syrup pump, the temperature and pressure differential of the sugar syrup mixture, coming from the mixer and water at the entrance of the mixer are all measured. The water-mass density is calculated by its temperature and the density of the sugar syrup mixture by its pressure differential. Afterwards the volume flow rate is worked out by the measured volume flow rate of water, by the estimated value of the density of water and sugar syrup mixture and by the density of ready sugar syrup measured in the laboratory. The dependency ratio of the active electric power from the volume rate of flow of the sugar syrup mixture and the differential in its pressure N=α1Q3 УΔPy+α2QyΔPy , where N - active electric power; QY - volume rate of flow of sugar syrup mixture entering the mixer; ΔPY - pressure differential of the sugar syrup mixture; α1, α2 - coefficients. The obtained plot is used for future calculations of volume rate of flow of sugar syrup mixture only with measured values of active electric power and pressure differential of the sugar syrup mixture. The current task of the regulator of the volumetric water discharge is determined on the basis of measured values of this output, estimated values of the density of sugar syrup mixture, water and volume rate of flow of the sugar syrup mixture, the determined value of density of ready sugar syrup mixture and the task of the regulator calculated in the previous control step. The solid content of the original sugar syrup mixture is controlled - by its temperature and density in the ready sugar syrup mixture. This invention makes it possible to reduce the loss of sugar from molasses due to a more qualitative stabilisation of the density of molasses on its exit from the mixer.
 Work environment remote control device / 2335795
Device contains control unit, temperature sensor, noise sensor and luminance sensor, temperature, noise and luminance signal converter per each sensor, boundary value generator per each controlled factor, comparator per each generator of maximum permissible values of measured temperature, noise, luminance, logic elements per each controlled factor, read-only storage per each controlled factor, shift registers, value counter of each controlled factor, control unit and generator. Besides, device contains relative humidity detector, air speed transducer and pulse number sensor, signal converters of relative humidity, air speed and pulsation factor per each sensor, boundary value generator per each additional controlled factor, comparator per each generator of each additional controlled factor, logic elements per each controlled factor, read-only storage per each controlled factor, shift registers, counter of maximum relative humidity, counter of minimum relative humidity, counter of air speeds, counter of pulsation factors.
 Work environment remote control device / 2335794
Device contains control unit, temperature sensor, noise sensor and luminance sensor, temperature, noise and luminance signal converter per each sensor, boundary value generator per each controlled factor, comparator per each generator of maximum permissible values of measured parameters, logic elements per each controlled factor, read-only storages per each controlled factor, four shift registers, counter of maximum temperature, counter of minimum temperature, noise counter, luminance, control unit and generator. Besides, device contains chemical sensor with converter, chemical concentration generator, logic element of maximum chemical concentrations, read-only storage of maximum chemical concentrations, shift register, counter of maximum chemical concentrations.
 Air humidity detector / 2332701
Invention can be applied for automated systems of microclimate control in closed warehouse space for improving accuracy of heat and humidity calculation in controlled variable air medium. Detector contains temperature sensor, relative humidity and atmospheric pressure detectors, temperature converter to air vapour pressure, and computing unit. Using of converter and atmospheric pressure detector allows for increased accuracy of humidity detection. Invention provides automated real-time humidity and increased accuracy of humidity detection.
 System of automatic temperature profile support in reactor / 2326424
Invention relates to the chemical industry, particularly to the automatic control systems and can be used for temperature support of the reaction mixture in chemical reactors. The system of automatic temperature profile support in the reactor with distributed constants in maleic anhydride production contains two control systems: cascade automatic control system (ACS) of coolant temperature control in the reactor and ACS of benzene-air mixture fed to the reactor where the correction signal is inleted according to reaction mixture temperature. The correction signal represents the sum of the signals about reaction mixture temperature in the measurement points positioned along the reactor height multiplied to the weight factor determined intuitively or from optimization problem solution. Then the correction signal is compared with assignment signal on the functional generator serving as algebraic adder. The invention allows to increase the temperature support accuracy in the reactor at maleic anhydride production.
 System of engine fuel supply / 2325547
System of engine fuel supply consists of fuel tank wherein the following is installed: a level meter connected to the inlet of a "fuel-water" level regulator, and a control valve to flow out commodity water; the said valve is connected to a control outlet of the regulator. The level meter is made as two sensors of the fuel level, located in a portion of the lowest allowable fuel level mainly at opposite sides of the tank and one water level sensor located at the flow out level. The control valve is assembled so as to provide a positive feedback with the regulator upon receiving a signal on water presence and a negative feedback when there is no signal entry. At the moment of a positive feedback and water flow out the regulator is programmed to let out not more than 100 kg of fuel.
 Method of controlling process of thermal destruction of petroleum residues in pipe furnace / 2318858
Method according to invention determines pressure gradients at exit and entrance in each section of the furnace and real gradient is compared to projected gradient, after which, depending on disagreement value, this value is diminished via variation of fuel consumption in corresponding furnace burner. Projected gradient is calculated using formula: ΔPi=k(L1+b)n, wherein ΔPi is pressure gradient in i-th section of coil, %; k, b, n are coefficients depending on conversion value, nature of raw material, and projected quality of final thermal destruction products; and L1 reduced length of coil from its beginning to i-th measurement point, %.
 Separator / 2314876
The invention is pertaining to the devices for purification of the gas flow from the solid and liquid particles and may be used in the different branches of industry and at the enterprises of the agro-industrial complex at operation of the pneumatic actuators, pneumatic installations, and also in need of usage in the production processes of the air and other gases. The separator is supplied with the automatic control system connected to the electrical slide valves connected with the inlet fitting pipe, the purified gas outlet fitting pipe and the fitting pipe for withdrawal of the separated particles. The separator also is supplied with the sensors of the temperature, humidity and pressure disposed on the inlet and outlet fitting pipes, the sensor of the level of the separated particles allocated in the lower part of the storage bin, the sensor of the gas flow speed connected to the gas flow speed controller. The sensors and the rotary valve drive are connected to the automatic control system. The technical result of the invention is automation of purification of the polluted gas flow from the solid and liquid particles at the heightened purification efficiency.
Method of production of the enriched carnallite / 2308417
The invention presents the method of production of the enriched carnallite and is pertaining to the chemical technology of the inorganic substances, in particular, to the technology of production of the enriched carnallite from the natural ores in compliance with the halurgy technology and may be used at the chemical enterprises producing the enriched carnallite. The offered method of production of the enriched carnallite provides for dissolution the carnallite ore by the mother alkali liquor, clarification of the saturated mother alkali liquor, the vacuum-crystallization of the carnallite from the saturated mother alkali liquor, thickening and centrifuging of the carnallite. The sediment of the carnallite received after the stage of the centrifuging is treated with the carbamide solution in the quantity of 0.01÷1.00 % from the mass of the sediment. The invention allows to prevent reduction of the output of the enriched carnallite.
Method of production of the artificial carnallite / 2307792
The invention is pertaining to the method of production of the artificial carnallite. The method of production of the carnallite includes mixing of the heated concentrated solutions containing potassium and magnesium chlorides, with the potassium chloride in the mass ratio of the solution equal to MgCl2:KCl = (3.2-7.9):1, cooling of the suspensions with crystallization, filtration the carnallite crystallizate, dissolution in the mother liquor at the temperature of 115°С of the waste electrolyte of the magnesium production and feeding of the produced solution for lixiviation of the magnesium chloride from the ore in the chamber of the underground lixiviation. Dissolution of the waste electrolyte of the magnesium production is conducted in the part of the mother liquor in the presence of the water or the sewage of the magnesium production containing magnesium, potassium, sodium chlorides for maintaining the water balance of the process of production of carnallite with reception of the solution containing 4-7 % of potassium chloride. The share of the magnesium chloride in the solution at the chamber outlet of the underground lixiviation is maintained at the level of 28-30 %.The solution received at the outlet of the chamber of the underground lixiviation is subjected to evaporation up to the share of MgCl2 in it at the level of 30-33 % and feed for mixing with the suspension of potassium chloride in the remained heated mother liquor. The method increases the share of extraction of potassium from the raw materials and the recycling solutions into the target product.
Potassium chloride and sodium chloride production process / 2307790
Invention is intended for use in chemical and mining industries to manufacture mineral fertilizers and food salts. Ground sylvinite ore is dissolved in recycled potassium chloride-saturated lye. Resulting solution is directed at a rate of 0.03-0.15 m/s to leaching in the first dissolution column, with its electrodes connected to one of a current source poles, and treated by low-frequency (1-5 Hz) alternating electric field at voltage 30-100 v. Solution thus enriched with potassium chloride is fed together with solid phase into the downstream second dissolution column with its electrodes connected to opposite pole of the current source. Treatment by alternating electric field in the second column is effected under the same conditions as in the first column. Two-step leaching results in potassium chloride solution and sodium chloride-enriched solid phase. Separated sodium chloride is sent to production of food salt. Potassium chloride is separated from solution via crystallization.
Method for chemical removal of impurities from chlorine-magnesium melt / 2307789
Method for chemically removing impurities from chlorine-magnesium melt comprises steps of melting solid dehydrated carnallite in vessel; treating prepared chlorine-magnesium melt by means of chemical reagent and agitating it; using as chemical reagent magnesium granules in salt envelope containing, mass%: metallic magnesium, 50 -95; chlorides of magnesium, potassium, calcium produced from salt casting waste materials of magnesium production by disintegration and separation to magnesium granules in salt envelope and to salt phase. Chemical reagent is fed onto surface or under layer of chlorine-magnesium melt. Chlorine-magnesium melt is treated in chlorinator or in furnace or in vacuum-ladle.
Method of preparation of the carnallite for electrolysis / 2305067
The invention is pertaining to the method of production of the enriched carnallite by its separation from the accompanying ores and impurities. The method of preparation of the carnallite for the electrolysis includes reduction of the carnallite ore, its air separation with partition of the carnallite and the halite, the two-stage dehydration of the carnallite. After reduction the carnallite ore is subjected to dressing within two stages in series: at first using the air separation in the furnaces of the fluidized layer at the temperature in the layer of 20-250°С and the gases speed in the layer of 1.5-7.0 m per second, then the produced carnallite is treated with the heavy suspension in the hydrocyclone. As the heavy suspension use the heavy brine of the potassium chloride with the density of 1.5-1.9 g/dm3. The invention allows to improve the quality and to increase extraction of the carnallite from the carnallite ore.
Method of production of the synthetic carnallite / 2299855
The invention is pertaining to the method of production of the synthetic carnallite for the electrolytic production of magnesium and chlorine and may be used in the nonferrous metallurgy and chemical industry. The method of production of the synthetic carnallite provides for dissolution of the spent electrolyte containing the magnesium chloride, potassium chloride, sodium chloride in the mother liquor of production of the carnallite up to the complete dissolution of the potassium chloride at the temperature of 90-115°С with the following filtration for separation of the non-dissolved sediment containing sodium chloride and production of the clarified carnallite-saturated solution. From the received solution the carnallite is crystallized by refrigeration with the speed of 17-25°С/h. The produced suspension is thickened and filtered for separation of the mother-liquor from the carnallite. The carnallite is dehydrated, dried and returned for intercalation in the dehydrated carnallite. The invention allows to produce the synthetic carnallite of the bigger size and with the low share of impurities.
 Method of processing carnallite dust formed at dehydration of magnesium-chloride material / 2299178
Proposed method of processing carnallite dust formed at dehydration of magnesium-chloride material includes delivery of raw material to fluidized-bed furnace, dehydration and entrapping of dust in cyclones. Dust is withdrawn from cyclones into reservoir, loaded into cyclone chamber and is molten in twisted flow of products of combustion of fuel and chlorine at simultaneous dehydration and cleaning from admixtures by chlorination procedure; thus melt of anhydrous carnallite is obtained which is directed for further use. Besides that, melting of carnallite dust is performed at temperature of 700-1200°C at rate of fuel combustion products at cyclone chamber inlet of 60-200 m/s; hydrogen chloride is used as chlorinating material. Finished anhydrous carnallite melt is used as carnallite flux which is directed to electrolyzers for production of magnesium.
Carnallite preparation process / 2294895
Invention relates to preparation of synthetic carnallite from magnesium chloride solutions using gallium chloride feedstock having as components potassium chloride or mixture thereof with magnesium production electrolyte. Process comprises mixing preheated concentrated magnesium chloride solutions with potassium chloride feed slurry, which has been prepared by interaction of a part preheated mother liquor with potassium chloride feed, subsequent cooling of mixture using vacuum crystallization, isolation of crystallizate, and recycle of the mother solution to starting reactants' mixing stage. Part of mother solution is treated at 90-100°C to isolate calcium sulfate with the aid of a metal sulfate taken in amount required to lower content of calcium chloride in solution to 0.9-1.5%, while maintaining calcium chloride concentration in the mixture of concentrated magnesium chloride solutions within a range of 3 to 6% by means of withdrawing a part of mother liquor for treatment with a metal sulfate. Mixing of solutions with starting reactant is conducted at 90-100°C. As a metal sulfate, aqueous solutions of magnesium sulfate, sodium sulfate, and potassium sulfate are used. As potassium chloride feedstock, potassium chloride or mixture with magnesium production electrolyte. When preparing slurry, preheated mother solution is supplied before or after removal of calcium chloride therefrom, or their mixture.
 Method of production of potassium chloride / 2264984
The invention is pertaining to methods of production of potassium chloride of the heightened purity. The method includes dissolution of the potassium-containing raw in a leaching solution, a crystallization of the end product from the hot clarified saturated with potassium chloride solution at the installation of vacuum crystallization with separation of the end product, a heating and feeding back of the mother liquor. At that dissolution of the potassium-containing raw conduct in a flotation machine in the leaching solution gained by treatment of the mother liquor with a chlorine-containing reactant with addition of an acid up to pH = 3-6. In the capacity of the chlorine-containing reactant is used a water solution of sodium or potassium hypochloride, chlorine, and in the capacity of potassium-containing raw - a halurgical or floatation potassium chloride. The method allows to produce potassium chloride with a reduced content of bromides in it.
 The method of coloring potassium chloride / 2234459
The invention relates to the field of production of fertilizers, in particular potassium chloride with distinctive coloring
Method of production of potassium chloride / 2264984
The invention is pertaining to methods of production of potassium chloride of the heightened purity. The method includes dissolution of the potassium-containing raw in a leaching solution, a crystallization of the end product from the hot clarified saturated with potassium chloride solution at the installation of vacuum crystallization with separation of the end product, a heating and feeding back of the mother liquor. At that dissolution of the potassium-containing raw conduct in a flotation machine in the leaching solution gained by treatment of the mother liquor with a chlorine-containing reactant with addition of an acid up to pH = 3-6. In the capacity of the chlorine-containing reactant is used a water solution of sodium or potassium hypochloride, chlorine, and in the capacity of potassium-containing raw - a halurgical or floatation potassium chloride. The method allows to produce potassium chloride with a reduced content of bromides in it.
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FIELD: chemistry. SUBSTANCE: invention can be used in the process of potassium chloride preparation by the method of solution-crystallisation. The method for the control of the aforesaid process by the way of input water flow varying includes: 1) the adjustment of water flow fed into crystallisation alkali liquor depending on potassium chloride concentration in the liquor and water consumption for washing of crystallisation apparatus; 2) detection of the temperature, density and consumption of alkali liquor. The said measurements allow to determine the sodium chloride content in the alkali liquor. The crystallisation water consumption is calculated on the basis of the obtained data according to proposed equation; the calculated values are input as assignment to the system of water consumption control. EFFECT: invention simplifies the process control of the potassium chloride preparation. 6 tbl, 2 ex
The invention relates to techniques for managing the process of obtaining potassium chloride gallerycheck method at the stage of cooling of the hot liquor and crystallization from him the target product. A known method of controlling the process of obtaining potassium chloride, stabilizing the content of potassium chloride in the product by changing the flow rate of weak solution of salts in the clay slurry and hot saturated lye - see speaker of the USSR №463633, CL C01D 3/04, publ. 1973. The method has a high complexity, since its implementation is impossible without the implementation of a complete chemical analysis of the input streams to determine the chemical composition of the system. Analytical control is a lengthy process, as it involves sampling in preparation for the analysis and determination of components in the system KCl-NaCl-H2O in the presence of MgCl2and other impurities. The results of the analysis comes to the production of potassium chloride with a delay of 3-4 hours, and in terms of large-scale production (for example, BY Uralkali flows entering the crystallization liquor reaches 1500 m3/h) they have a significant impact on the progress of the process does not have. Therefore, the full chemical analysis used statistical material. In practice, to guarantee the quality of kristalliset chloride is th potassium vacuum crystallization setting serves the increased consumption of water. In a small content of chlorides of magnesium and calcium in the ore (less than 0.5%) this leads to a significant loss of potassium chloride by removing excess liquor from the process of obtaining a concentrate. A known method of controlling the process of obtaining potassium chloride by changing the costs of input streams - see prototype speakers of the USSR №948884, CL C01D 3/04, G05D 27/00, publ. 07.08.82. Bull. No. 20. The method provides for the stabilization of the content of potassium chloride in the product by controlling the flow of water coming in on the crystallization liquor depending on the temperature of the liquor, the concentration of potassium chloride, water consumption for flushing crystallization apparatus, flow and temperature of the circulating liquor. The proposed method also regulate the water flow in the apparatus for separation of the liquor from kristalliset depending on the specific content of potassium chloride in the product and consumption of the circulating liquor. The known method is complex, as it does not take into account the actual content in the hot liquor entering the vacuum crystallization unit (ADC) of sodium chloride. With the shortage of water, the flow of which is regulated by the quality of the product, is the crystallization of the cooled liquor of sodium chloride and deterioration in the quality of kristalliset. Therefore, there is a method to include trivet water supply in the apparatus of the Department of liquor from kristalliset. This technique does not always produce a positive result, as the sodium chloride crystals grow crystals of potassium chloride and are not washed out by washing. Increased consumption of water at the UWC entails unbalance in the water, excessive liquor, and loss of useful component. The method also involves the use of methods of analytical control. The task of the invention is to simplify the process of operational management by automating the flow of water depending on the composition and flow rate of the liquor entering the vacuum crystallization installation. This objective is achieved in that, in contrast to the known method, additionally measure the density and consumption of liquor, temperature, density and the content of potassium chloride, by calculation, determine the content of the liquor to sodium chloride and the obtained parameters calculate the flow rate of water supplied to the crystallization, according to the following dependence and the calculated value serves as the task management system water flow:
whereot/h;1t/h;2t/h;3and In23- the dimensionless coefficients which are determined based on the calculation of the material balance of the process of crystallization; Qwater- the water flow on crystallization, t/h; shch-- consumption of liquor supplied to the crystallization, t/h; Fwater- water consumption for technological needs, t/h; CKCl s-K- mass fraction of KCl in the liquor; CNaCl Sch-- mass fraction of NaCl in the liquor, as defined calculated based on: CNaCl Sch-= -Ao/A2+ρshch-/A2-A1CKCl s-K/A2, where ρshch-the density of liquor, t/m3; Ando, A1and a2- the empirical coefficients determined by mathematical processing of empirical data, t/m3. The method consists in the following. In contrast to the known method, the proposed method additionally measure the density and consumption of liquor; temperature, density, and concentration of potassium chloride calculated to define the content of the liquor to sodium chloride and the obtained parameters determine the water flow on the crystallization based on: Qwater= o+B1CKCl s-KIn2CNaCl Sch-In3Qshch-+ 23Q)shch-·CNaCl Sch-- Fwater where InoIn1In2In3In23are coefficients determined based on the calculation of the material balance of the process of crystallization; Qwater- the water flow on crystallization, t/h; Qshch-- consumption of liquor coming into Chris is alizatio, t/h; Fwater- water consumption for technological needs, t/h; CKCl s-K- mass fraction of KCl in the liquor; CNaCl Sch-- mass fraction of NaCl in the liquor, as defined calculated based on:
where ρshch-the density of liquor, t/m3; AndoAnd1And2- the empirical coefficients determined by mathematical processing of empirical data. In matter:
And have a value of:
The quality management of the target product are addressed mainly at the stage of crystallization of potassium chloride from a saturated hot clarified liquor from the stage of dissolution for the installation of vacuum crystallization (ICD). Analysis of data on the chemical composition of liquid phases shows that the NaCl content in the saturated liquor at the entrance to the internals exceeds the saturation concentration, i.e. the solution contains a solid phase sodium chloride and its content may reach 16 kg per cubic meter of solution. The presence of sodium chloride in the clarified liquor is explained by the removal from the stage clarification of crystalline NaCl, crystallising from a saturated solution from the stage of clarification due to its cooling at 1-2°C and the partial evaporation of the water in the clarifiers John. NaCl content in a saturated solution is one of the most important factors determining the flow of water in the process. With increased content NaC water should be made directly to the receiving tank internals in number, providing for the dissolution of sodium chloride. If the water flow is insufficient, the complete dissolution of the salt slurry does not occur, and NaCl, remaining in the solid phase, then covered with crystallized KCl. Water flow through the stages internals this leads to the fact that the mother solution becomes unsaturated in NaCl, and crystallized contains NaCl, resulting in impairment of the quality of the final product. It should be noted that to avoid production of defective products process leading to the issue, for example, 96%of the product instead of 95%, resulting in lower product yield and increase consumption rates of ore and excessive liquor, i.e. leads to the reduction of technical and economic indicators of production. At existing gallerycheck factories consumption of water at the UWC adjust to suit the load, the content of potassium chloride in the liquor and density. Quantitative patterns of water flow at the UWC depending on the input variables of the process is not formalized and operational process control vacuum crystallization are ignored, and the process is carried out according to the results of analytical control. In the proposed method, in contrast to known methods, the management process of obtaining potassium chloride is produced by a change of the input stream in the s by 1 and 2. When developing a mathematical model stage crystallization of potassium chloride has been shown that one of the significant factors that must be considered in the management process, is the mass fraction of NaCl in the feed to the crystallization liquor. Direct measurement of mass fraction of NaCl using the instrumentation is not possible. Therefore, the implemented calculation method for the determination of NaCl on the basis of the automatically measured parameters: the mass fraction of KCl, density and temperature of the liquor on the basis of use developed in VNIIG "Method of coefficient - see method of calculation of the density of the complex salt systems. Proceedings of VNIIG, vol. No. 36, Goskomizdat, 1959. This method allows to determine the empirical coefficients A. Applying a known method three-factor experiment (see, for example, Planning of experiment in chemistry and chemical technology". The Sautin S.N. Ed. "Chemistry", L., 1975) when processing the resulting technological calculations of data received basic equation relating the density of the liquor with its composition and temperature:
Transforming this equation, we obtain the dependence (2) the mass fraction of NaCl in the feed to the crystallization liquor. Dependence for water consumption represents a nonlinear equation describing the optimal the second flow value for the permissible ranges of values of the independent variables of the crystallization process. As independent variables taken: CKCl s-K- mass fraction of KCl in hot clarified saturated liquor; CNaCl Sch-- mass fraction of NaCl in the clarified saturated liquor; Qshch-- consumption of liquor supplied to the crystallization, t/h; Fwater- water consumption for technological needs, t/h Water consumption (Fwaterfor each manufacturer of potassium chloride by the method of crystallization from hot clarified liquor has its value and is determined by the type of installation, vacuum crystallization. For Multihull vacuum crystallization install without control the crystal growth water consumption (Fwateris fixed by the regulation value, which is usually 5-10% of the water flow on crystallization (Qwater). This water is consumed for technological needs - washing piping, sight glasses, etc. Selection of water for technical needs (Fwater) after regulation of its flow by the dependence (1), while the remaining water after selection for technical needs, usually served in zapotocny glass internals. When using multiple installation with adjustable vacuum crystallization water consumption consists of the consumption for technological needs, as well as the consumption of water supplied in the external account is s each corps RWCU for dissolution of small classes KCl. This water is firmly fixed, and introduced into the dependence (1) in the form of a constant value of the coefficient (Fwater). On some installations adjustable vacuum crystallization (RWCU) served in zapotocny glass heated solution cyclone dust. Water consumption for the dissolution of the cyclone dust also measured and taken into account in the factor Fwater. When selecting production of a suspension of the intermediate chassis RWCU with subsequent separation and washing of kristalliset liquor and prambody return in case RUKU. Water consumption for washing kristalliset measured and accounted for in the coefficient Fwater. Kinetic regularities of the process of crystallization of KCl taking into account the residence time of the solid phase on the hull internals, the rate of formation and growth of crystals, etc. are incorporated in the projects crystallization plants. Therefore, used to control stage vacuum crystallization static model does not take into account the influence of the above kinetic factors. The production of a given product requires changing technological mode of conducting the process of crystallization by increasing the water flow in accordance with the water balance, therefore, according to different numerical values of the coefficients for each of the obtained product: 96,5 and 98% KCl or other. The total quantity and the creation of material balance calculations in the planning matrix was 2 5or 32. Material balances that determine the water flow rate was calculated according to standard techniques (see, for example, "Technology of potash fertilizers". Kashkarov OD, Sokolov, I., Ed. "Chemistry", L., 1978) and is not contained in the description of the present invention because of grimscote and widely known methods of calculation. Material balances of the processes of crystallization of KCl for one type of product to 96.5 or 98% KCl - taking into account the zero error of the instrument, with which they control the value of process parameters, carried out in the traditional way using charts solubility of salts in the system KCl-NaCl-H2O in the presence of MgCl2because this system does not form supersaturated solutions. Next performed similar calculations, taking into account the lower and upper levels of the maximum permissible error of the instrument, did an assessment of the technological reproducibility of the calculations, the calculation of the regression coefficients, assess their significance and adequacy of the regression equations in accordance with the method of mathematical planning ("Planning experiments in chemistry and chemical technology". The Sautin S.N. Ed. "Chemistry", L., 1975). Table 3 shows the levels of the factors and their intervals of variation for the crystallization of KCl, for example, for processing liquor generated during the processing of ores Verkhnekamsk the field.
Table 4 shows the results of the determining factors In considering exceptions to the equation insignificant coefficients.
After substitution of the above factors the addiction to control water flow for two kinds of products will take the form: Qwater 96,5%KCl=6,166+0,005·KCl s-K-35,9833·NaCl Sch--0,6934·Qshch-+4,3372·Qshch-·NaCl Sch-- Fwater Qwater 98% KCl=0,031+0,005·KCl s-K-0,1667·NaCl Sch--0,6713·Qshch-+4,24·Qshch-· WithNaCl Sch-- Fwater Table 5 shows the levels of the factors and ranges of their variation to determine the empirical coefficients A.
The coefficients obtained after the conversion formula (2) in accordance with the method of regression analysis (design of experiments in chemistry and chemical technology. The Sautin S.N. Ed. "Chemistry", L., 1975). Dependence to calculate the mass fraction of NaCl in the solution will have the form: WithNaCl p. p-p= -1,1188+ρshch./0,8333-0,8·CKCl/0,8333 Given the levels of factors and ranges of their variation fair for processing of sylvinite ores at the operating sylvinite factories, such as OJSC "Silvinit", with selected technological parameters, covering all possible changes of the technological process of crystallization of potassium chloride from clarified seloka. Thus, the task of simplifying the management process of crystallization of potassium chloride from the clear saturated liquor on internals due to the replacement of long-term analytical control automatic analyzer potassium and low-inertia automatic sensors of process parameters - temperature, flow, and density using the results of measurement for automatic control of water flow by primenenie PC in the supervisor mode. The method is as follows. Hot clarified rich liquor with temperature 95,5±1,0 directed to the vacuum crystallization installation, thus determine the temperature of the liquor through a thermal Converter with unified output signal - for example, TSMU-055; density - for example, using a primary Converter MFS2000 and signal Converter MFS081, and its consumption-for example, by the induction flow meter type SORA HEH. Mass fraction of potassium is determined by measuring potassium - for example, the company "Bertold" LB 377-62. The signals from the transducers are received at the controller and the PC, where it calculates the optimal setting of water flow. The optimal value of the job enters the control loop water flow at the UWC. In the case of using water for technological needs - for example, on the dissolution of the cyclone dust with subsequent supply of KCl solution at the UWC in conjunction with water or along the contours of RUKU, and when the supply of water for technical needs, water for these purposes is fixed and is taken after the water meter at the UWC. Examples of the method Example 1: 1. The readings for determining the mass fraction of NaCl have the values: 0,203 - mass fraction of KCl in the clarified liquor; 1,244 - density of liquor, g/cm3; The calculation of the mass fraction of NaCl in the solvent Selo the e: CNaCl R. R-R= -1,1188+ρshch./0,8333-0,8·CKCl/0,8333, CNaCl R. R-R= 0,1792 Mass fraction of NaCl used in the calculation of water flow. 2. The performance of devices for determining the flow rate of water have values: 1500 - consumption of liquor, t/h; 35 - water consumption for technical needs, t/h Calculation of water flow rate: Qwater= 6,166+0,005·0,203-0,6934·1500-35,9833·0,1792+4,3372·1500·0,1792-35 Qwater= 90,459 t/h The calculated values of water flow serves as a job management system water meter. A survey of automatic devices is performed with an interval of 10 seconds Management was carried out of the calculate of potassium chloride with KCl content of 96.5%. Actually received purged with KCl content 96,7%. Example 2: The performance of devices for determining the flow of water to obtain 98% KCl. 0,203 - mass fraction of KCl in the liquor entering internals; 1500 - consumption of liquor, t/h; 35 - water consumption for technical and technological needs (Fwater), which is the sum of the consumption of water on the dissolution of the cyclone dust - 15 t/h water consumption for flushing kristalliset 5 t/h water flow in the external circuit - 15 t/h Calculation of water flow from the condition that CNaCl Sch-= 0,1792 - see example 1. Qwater= 0,031+0,005·0,203-0,6713·1500-0,1667·0,1792+4,24·1500·0,1792-35; Qwater= 97,765 t/h Management conducted based receiving chloride feces what I KCl content 98,0%. Actually received purged with KCl content of 98.2%. The process control method of obtaining potassium chloride by changing the input flow of water, including adjustment of the flow rate of water coming in on the crystallization liquor depending on the concentration of potassium chloride, water consumption for flushing crystallization apparatus and determining the temperature of the liquor, characterized in that it further measure the density and consumption of liquor, temperature, density, and concentration of potassium chloride by calculation, determine the content of the liquor of sodium chloride, and the obtained parameters calculate the flow rate of water supplied to the crystallization, according to the following dependence, and the calculated value serves as the task management system water flow:
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