Automated method of controlling and managing process for preparing sugar syrup mixture for crystallisation by cooling |
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IPC classes for russian patent Automated method of controlling and managing process for preparing sugar syrup mixture for crystallisation by cooling (RU 2342438):
                                                                                                                                                                               
 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.
 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 control over the process of decomposition of the aluminate solution in the alum earth production / 2310607
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.
 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 producing host crystal for fillmass boiling / 2342437
Present invention pertains to the sugar industry, particularly to fillmass boiling. The method involves preparation of a suspension of granulated sugar and isopropyl alcohol, grinding sugar crystals in the suspension until a paste is formed, turning it into thick syrup, and growing crystals through cooling. The sugar crystals in the suspension are ground to particle size of 25-30 mcm. The paste is converted to syrup with supersaturation coefficient of 1.05. The crystal mass is cooled for 6 hours until attaining host crystal size of 0.20-0.25 mm.
Method of brown sugar affination / 2340679
Method implies mixing final-product brown sugar with high green diluted up to 74-76% of solids content. The obtained affination massecuite is centrifuged. Prior to affination high green is treated by ozone-air mixture with the ozone concentration in the mixture equal to 5-15 g/m3 and with the amount of ozone-air mixture equal to 2-4 nm3/m3 of the runoff.
 Method of sugar production / 2335545
Method involves preparation of sulfurated and filtered affinated raw sugar remelt syrup taken in amount of 5-10 kg per 100 kg of beets. 0-runoff is boiled from the described remelt syrup, brown sugar B-runoff remelt syrup and second 0-runoff syrup and centrifugated to obtain refining grade sugar and two runoff syrups. A-runoff is boiled from beet sugar syrup and first 0-runoff syrup and centrifugated to obtain white sugar and two runoff syrups. B-runoff is boiled from crystal base made of C-runoff brown sugar and second A-runoff syrup. B-runoff is centrifugated to obtain B-runoff brown sugar and two runoff syrups. C-runoff is boiled and crystallised by cooling, centrifugated to obtain C-runoff brown sugar and molasses.
Method of sugar production from raw cane sugar at beet sugar facility / 2335544
Method involves preparation of mix of raw sugar remelt syrup and 30% of runoff syrup weight from crystallisation A-runoff, and A-boiling. Part of this runoff syrup with crystal size of 0.6 mm is separated from vacuum pan and centrifugated to separate white sugar and two runoff syrups, which are mixed with original raw sugar remelt syrup. This mix is fed to boiling of runoff syrup part remaining in the vacuum pan. After discharge from the vacuum pan runoff syrup undergoes additional crystallisation by cooling in massecuite mixers. B-runoff from A-runoff remainders is boiled. C-runoff is boiled and centrifugated to separate brown sugar of C-runoff and molasses.
Method production of final-product sugar / 2331672
Invention pertains to the technology of sugar production, and more specifically to obtaining final-product sugar. The method involves fillmass boiling in a vacuum apparatus to a given content of dry substances from inter-crystal fillmass molasses of the previous crystallisation stage, putting this fillmass into a crystallisation device, crystallisation of the fillmass by cooling it and its concentration with separation of sugar crystals from the molasses. A middle sample of the fillmass is taken, which is supplied for boiling the fillmass. The sample is condensed and crystallised. The obtained fillmass is cooled to 60-65°C and concentrated with tapping off of massecuite syrup, from which several samples are prepared by diluting with water until 80-84% content of dry substances is attained. Sugar in quantity of 20-25% of the mass of the sample is added to each sample. The samples are stirred for 1.5-2.0 hours at 60-65°C until a saturated state is attained. The samples are then centrifuged with separation of massecuite syrup and their content of dry substances, purity and viscosity is determined. From the obtained results and the required content of crystals in the fillmass, the optimum content of dry substances in the fillmass at the end of boiling is calculated, as well as purity of the molasses, channelled for boiling this fillmass. The calculated value of purity of molasses is corrected by putting a sugar containing solution into the molasses until the obtained calculated purity value of the molasses is attained.
Iodated cube sugar / 2328532
Method stipulates missing of granulated sugar with dry tangle extract in form of powder with degree of dispersion less than 0.2 mm at thorough agitation till indiscrete mass receiving, pressing with following filling and packing. Dry extract is received with drying of tangle liquid aqueous extract till humidity no more than 15%. Liquid aqueous extract is received with aquatic extraction with correlation of dry matter and water 1:5 - 1:30 at the water temperature 80-90°C preliminary grained till particle size of tangle less than 5cm with following filtration and adding of hydric dioxide aqueous solution, with concentration 1-40% and quantity 0.01-5.0 ml for 1 l of extract.
Method of reception of massecuite strike of first crystallisation / 2327741
Method provides preparation of remelt sugar syrups of the second and third crystallisation, their condensation in the vacuum-device, crystal formation with their subsequent escalating in two steps, and a definitive condensation of massecuite strike. Crystal formation is carried out by spontaneous formation of the centres of crystallisation in quantity of 5-7 pieces on 1 mm of surface length of trial glass at super-saturation coefficient 1.30-1.36, keeping it within 5-15 minutes. Escalating of crystals at the first step is carried out by pumping in vacuum-device of a syrup to their content in massecuite strike 50-55%, keeping distance between them 1.5-10-4 - 2.5-10-4 m. At the second step crystals is formatted by pumping to the device of remelt sugar syrups of the third crystallisation containing 70-75% "СВ" with addition of heating to 50-60°C distilled monoglyceride in quantity of 0.001-0.002% to remelt syrups mass.
Sugar production method / 2323257
Method involves filtering first carbonation juice; melting raw sugar at temperature of 85-90 C; mixing sugar melt with filtered first carbonation juice; providing liming of mixture, saturation, filtration, third saturation, and filtration of mixture resulted from third saturation procedure; providing melting of raw sugar using second carbonation juice suspension in the ratio of one part of raw sugar to 2.2-3.0 parts of said suspension; processing resulted sugar melt with pulsed magnetic field during 9-11 s and after processing directing it for mixing with said filtered first carbonation juice. Method allows clearing effect to be increased by 1.5-2.0% as compared to prior art method, content of high-molecular compounds in mixture to be reduced by 21-25%, calcium salt content to be reduced by 19-22%, and color intensity of clarified juice to be reduced by 18-20%.
Sugar production method / 2323256
Method involves filtering first carbonation juice; melting raw sugar using said filtered juice in melting mixer at temperature of 85-90 C; introducing into mixer sodium hypochloride in an amount of 0.03-0.05% by weight of raw sugar and finely dispersed keramzite powder in an amount of 0.3-0.5% by weight of raw sugar; mixing resulted sugar melt with filtered first carbonation juice; liming mixture; providing saturation, filtration, third saturation, filtration and evaporation of rectified mixture for producing of syrup; processing sugar melt containing sodium hypochloride and keramzite powder with pulsed magnetic field having induction of 0.30-0.35 T during 9-10 s; directing it for mixing with said first carbonation juice.
Method for producing of first fillmass / 2321640
Method involves condensing thin juice in quadruple-effect evaporator installation with concentrator; taking out condensed juice from third evaporator and providing decoloration; condensing juice in third evaporator of evaporator installation until dry substance content is 38-45%; decolorating condensed juice taken out of said evaporator by treating with ozone-air mixture with ozone concentration of 7-12 g/m3 during 5 min at flow rate of 2-4 m3/m3; introducing activated coal into condensed juice in an amount of 0.2-0.6% by weight of condensed juice; filtering condensed juice and feeding into forth evaporator; mixing syrup delivered from concentrator with remelt sugar and filtering; evaporating filtered syrup in first fillmass vacuum evaporator.
Method for manufacturing sugar / 2244012
Method involves purifying diffusion juice, clarifying crude sugar, evaporation of juice to obtain syrup and crystallization of syrup in vacuum-apparatus. Clarifying crude sugar is carried out by taking off part of purified juice feeding to evaporation and addition crude sugar to it up to the content of dry matters in clarification 55-65%, or by addition of crude sugar to syrup obtained after partial evaporation of purified juice up to attainment of indicated content of dry matters in clarification. Clarification obtained in the first case is mixed with syrup of the remainder amount of purified juice with the content of dry matters 55-65%. Before the boiling out process obtained clarifications are subjected for purification. Invention provides processing large amount of crude sugar with beet simultaneously, to enhance the yield of the ready product and to reduce specific energy consumptions in evaporation of sugar-containing solutions.
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FIELD: chemistry, sugar production. SUBSTANCE: 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. EFFECT: reduction in the loss of sugar from molasses due to a more qualitative stabilisation of the density of molasses on its exit from the mixer. 3 dwg, 1 ex
The invention relates to methods of automatic control and management of the preparation process of the massecuite to crystallization by cooling and can be used in the sugar industry during crystallization of sugar. The known method for automatic process control of crystallization of sugar in the mixer-molds for the regulation of cooling water in the jacket thelemically depending on the measured temperature of the cooled massecuite (Eselevich ME and other Basics of automating the processes of beet sugar production. M: Food industry. - 1968, s). The disadvantage of this control method is that it does not provide for the regulation of the density of the massecuite, is supplied into the mold, and may not be used to control the process of preparation of the massecuite cooling in a vertical crystallizers. The closest in technical essence and the achieved effect to the proposed method is a method for the automatic control of the process of preparation of the massecuite to crystallization by cooling in a vertical mold, providing for the regulation of the volume flow of water into the mixer and level of massecuite in it, the regulation level of the massecuite in a vertical mould by affecting variable frequency drive massequite pump, enabling the th periodic laboratory monitoring of the density of the finished massecuite at the exit of the mixer. To maintain the setpoint solids content after the mixer is used periodic analytical control of this parameter with the correction job flow ammonia water and, if necessary, the ratio of the massecuite:water (Vinchur, Accedence, Upoko, EMedia, Vampisoul, TI Leonov, L.A. Shatalov. Experience of implementation of vertical crystallizers in sugar refineries company Rusagro.//The sugar. - 2002 - No. 3. - P.53...55). The disadvantage of this method of control is that it is not possible to achieve reliable operation of the control circuits, intended for stabilizing the density of the massecuite at the output of the mixer (Vinchur, Accusense and other Experience in the implementation of vertical crystallizers in sugar refineries company Rusagro.//The sugar. - 2002 - No. 3. - P.55, lines 11...33 above). Also this method does not allow to automatically control the solids content in the massecuite at the entrance and at the exit of the mixer. The technical problem of the invention is to reduce losses of sucrose from molasses due to better stabilization of the density of the massecuite at the entrance to the vertical mould and automation control of the content of dry substances in source and finished massecuite. This result is achieved in that in the method of automatic control% som preparation of massecuite to crystallization by cooling, providing for the regulation of the volume flow of water into the mixer and level of massecuite in it, the regulation level of the massecuite in a vertical mould by affecting variable frequency drive massequite pump, including periodic laboratory monitoring of the density of the finished massecuite at the exit of the mixer, it is new that additional measure active electric power consumed by the electric drive massequite pump, temperature and pressure massecuite entering the mixer, the water temperature at the inlet to the mixer, calculate the density of water at its temperature and density of the massecuite by its pressure drop, calculate the volume flow of massecuite in the mixer on the measured volumetric flow rate of water the calculated values of water density and massecuite and laboratory measured density of the finished massecuite, determine the dependency ratios of the active electric power from the volumetric flow of massecuite and the differential pressure
where N is the active electrical power; Qy- volume flow of massecuite in the mixer; ΔPy- the pressure drop of the massecuite; and1and2are coefficients and use this relationship for the subsequent calculation of the volume flow of massecuite only on the measured values of active is elektricheskoi capacity and pressure drop of the massecuite, determine the current setting of the slider of the volume flow of water based on the measured values of the flow rate, the calculated values of the density of the massecuite, the water and the volumetric flow of massecuite, the set value of the density of the finished massecuite and set the regulator calculated at the previous step control, control the content of dry substances in the source massecuite on its density and temperature, in the finished massecuite volume costs and density of the source of the massecuite and the water and the solids content in the source massecuite. The technical result of the invention is illustrated by the example of its implementation and figures 1 and 2. Figure 1 shows a control circuit that implements this method. Figure 2 shows experimentally obtained comparative graphs of the time variation of the density of the finished massecuite at the output of the mixer (figa) and purity microcannula solution of massecuite before centrifugation (figb) in managing the process of preparation of the massecuite to crystallization by cooling using a known method (figures 1,3) and using the invention (figures 2,4). Method for automatic control and management of the preparation process of the massecuite to crystallization by cooling is implemented as follows. Massequite pump unit 1 delivers the original massecuite in the vertical pipe 2 into the mixer 3. what about the pipeline 4 into the mixer 3 is fed ammonia water. From the mixer 3 finished massecuite is fed into the vertical mold 5, the level of the massecuite which is controlled through a circuit including a level sensor 6, the controller 7 and the inverter 8 drive massequite pump 1. The differential pressure of the source of the massecuite in the pipeline 2 and the temperature of the massecuite is measured respectively by the sensors 9 and 10. Volumetric flow rate of ammonia water in the mixer 3 is measured by the sensor 11 and handle with knob 12 and control valve 13. The level in the mixer is controlled by the circuit including the sensor 14, the controller 15 and control gate 16. The temperature of the ammonia water is measured by the sensor 17. Active electric power consumed by the electric drive massequite pump 1, is measured by the sensor 18. Information from the sensors 9, 10, 11, 17, 18 arrives at the inputs of the functional block 19, which is calculated setting the controller 12 of the flow rate of the ammonia water in the mixer and calculate the content of dry substances in source and finished massecuite. In block 19 from the engineerís is also information about laboratory measured density of the finished massecuite The dependence of the density of the massecuite from the content of the SV is calculated according to the formula, which evaluated the accuracy to calculate latest sugar solution (Deenet-Radchenko, Samuilenko, Kottenheim. The calculated dependences of thermophysical properties of sugar solutions.//Sugar.- 2004 - No. 1. - S.43):
where ρB(t) is the density of water. The density of the massecuite is determined by the block 19 by the hydrostatic pressure drop of the liquid column, measured by the sensor 9:
where ΔPythe differential pressure measured by the sensor 9, N/m2; g - acceleration of free fall equal to 9,81 m/s2; Hy- the height of a column of the massecuite in the pipeline 2, m Temperature of the massecuite is measured by the sensor 10, °C. Thus, using equation 2, 3, 4 can be calculated content of dry substances in the massecuite STy. The calculation of ST.yis the block 19 by the formula:
where
The optimization problem (5) is formulated as follows: determine the value of content As is ormula (2) the dependence of the content of ST yfrom the density of the massecuite essentially nonlinear and is not solved analytically to calculate SVyfordensity and temperature, you must use one of the methods of nonlinear programming, such as the configurations of hook-Jeeves (Shoop So the Solution of engineering problems on computers: a Practical guide. TRANS. from English. - M.: Mir, 1982. - 238 S. str...182). Due to the fact that when STycan get negative values or large 100%, then the value of STyit is necessary to impose limitations due to the technological regulations:
Constraints (6) the objective function (5) can be written as follows:
Found the block 19 by the formula (7) On the basis of material balance, the density of the prepared diluted massecuite at the output of mixer ρcmcan be defined as follows:
where Qy, QB- volume flow in the respective mixer is about massecuite and water. In the formula (8), the unknown parameters are the volume flow of massecuite Qyand density of diluted massecuite ρcm. If measured by the laboratory density of the massecuite mixer
On the other hand the volume flow of massecuite is determined based on the measured sensor 18 active electric power of N consumed by the electric drive of the pump 1. For this we use the formula (Pavlov CYP, Romankov p. g, Socks, A.A. Examples and problems at the rate of the processes and apparatuses of chemical technology. - M.: Chemistry, 1969, 624 S., p.28, formula 1-32):
where ΔPWith- the hydraulic resistance of the network, N/m2; η - efficiency massequite pump unit. Value ΔPWithcalculated as the sum of the following terms ΔPWith=ΔPSC+ΔPTr+ΔPMS+ΔPunder+ΔPSS, ΔPSC- the cost of pressure to create flow velocity, N/m2; ΔPTr- loss of pressure to overcome the resistance of friction, N/m2; ΔPMS- pressure loss at overcoming local resistance, N/m2; ΔPunder- particularly the s pressure rise of the fluid, N/m2; ΔPSS- loss due to the difference of the pressures in the spaces of the suction and discharge side of the pump, N/m2. Loss of pressure on the friction of the massecuite can be defined by the formula Hagen-Poiseuille flow (Pavlov CYP, Romankov p. g, Socks, A.A. Examples and problems at the rate of the processes and apparatuses of chemical technology. - M.: Chemistry, 1969, 624 S., p.30, formula (1-40)):
where L is the length massequite pipeline, m; d - internal diameter, m; ω - speed laminar flow, m/s; μYthe viscosity of the massecuite, PA·C. But
where Re is the Reynolds criterion. Loss of pressure on the rise of the massecuite is
Cost pressure to create flow velocity is expressed by the formula:
Loss ΔPMSand ΔPSSnot be more than 5...10% of all pressure losses. The average value of the criterion when you're pumping massecuite is about 1. The error in the calculation of pressure losses by friction under the assumption that Re≈1, also is not more than 5...10%. Let us assume that the unaccounted-for pressure, as well as the error in the calculation of pressure losses by friction, form part of the total pteridine Δ PSC+ΔPTr+ΔPundercalculated by the formula(12), (13), (14). Then the hydraulic resistance of the network is equal to:
where a is a coefficient less than 1. Taking into account (15) active electric power will be equal to:
where the constant We substitute (9) into (16) and get
where How easy is defined As:
where [K] - step adjustment of model (17), depending on the frequency of laboratory monitoring density. Thus, on the basis of laboratory analysis in [K] the step of adjusting the density of the diluted massecuite Considering And[K]the dependence of active power from the volumetric flow of massecuite will be:
where [n]is the current step of measuring and control. The solution of equation (19), in which the unknown is the volume flow of massecuite
With the technological constraints on
The solution of (21) is determined by the current value of the flow of massecuite Calculating the current value of the flow of massecuite
The job controller 12 water consumption is calculated by the block 19 by the formula:
where
The current job to control water flow calculated by the formula (23), remember, is converted into a control signal and is supplied from the output unit 19 in Cham is the job of the regulator 12. Stored value task is used in the formula (23) in the next step as the value of the last job step control. The definition of the parameter a is performed by adjustment of the present invention. During operation when performing only routine laboratory tests the density of the diluted massecuite may be the adjustment of the values of this coefficient. The formula for the adjustment is as follows:
where
α - smoothing coefficient, determined experimentally in the range of 0.5≤α≤1. The proposed method allows to reliably zastabilizirovat at a given value of the density of the prepared diluted massecuite at the exit of the mixer, as the formula (19) is uniquely associates the volume flow of massecuite and the active electric power consumed by the electric drive massequite pump, and the density of the massecuite and water are calculated automatically. The DM contentcmat the output of the mixer is calculated by the block 19 by the formula:
where GCBWithy, GBmass costs relevant to the military solids, the massecuite and water in the mixer, kg/s, is equal to:
where CByvalue of dry substance concentration calculated by the formula (7). Method for automatic control and management of the preparation process of the massecuite to crystallization by cooling is illustrated by the following examples. Example 1. The calculation of the job flow regulator water The design parameters of the control system that implements the method, is equal to: Hy=14.2 m; L=22.5 m; d=0,158 m Then the structural coefficient, defined by the formula (16), equal to:
Measured by the laboratory density of the prepared diluted massecuite ΔPY=205000 N/m2(sensor 9); QIn=0.25 m3/h=6,9444·10-5m3(sensor 11); tIn=72°With (sensor 17); N=988 W (18 gauge). Calculated by the formula (3) density of water is equal to: ρIn=976,93 kg/m3(based on information from the sensor 7). The density of the massecuite, defined by the formula (4), is equal to: ρy=1471,62 kg/m3(based on information from the sensor 9). According to the formula (18) defined by the configuration parameter:
Measured in [n] step control parameter values were equal to:
N[n]=1090 watts. Then
Prepare the cubic equation (19) 1090=(85191,547· 85191,547 Deciding composed of a cubic equation in terms of restrictions Thus, the current volume flow of massecuite, calculated on a [n] step equal to Suppose that a job density of the finished diluted massecuite is
If, for example Thus, the change in job density of the diluted massecuite only 10 kg/m3the Veda is to change the job of water flow on 0,142 m 3per hour or 25% of the original task, i.e. the sensitivity of the regulation on the channel density of the diluted massecuite flow of water is very high. This explains the poor quality of the regulation of the density of the diluted massecuite in the prototype, which is carried out according to the specified ratio of the massecuite:water. Suppose the value of the job to the controller 12, calculated by the block 19 in the past [n-1] step equations, it is Example 2. The calculation of the concentration of solids To calculate the dry matter content of at the entrance to the mixer using the formula (2). The current density of the massecuite is
the solution is The consumption of dry matter equal to
Find the mass spending the odes and massecuite:
Then by the formula (25):
Thus, the concentration of the army in the inlet and outlet of the mixer are respectively 94,17% and 90,59%. Experimental verification of the proposed method for automatic process control training of massecuite to crystallization by cooling showed its high effectiveness and efficiency (figure 2). The average purity microcannula solution of massecuite at the output of the vertical mold decreases with 54,24% (when controlling for known way) to 54.0% (when controlling for the proposed method) (figb.). Implementation of the functional block 19 is carried out using computer equipment. As the primary measuring transducers can be used: - intelligent sensors differential pressure Metran-100-DD, measurement error ±0,1%; - resistance copper SCI Metran-204 (100M) with measurement error ±0,25+0,0035(t) %; - rhodometra Metran-360 error ±0,5%; - wattmeter TS-201. Using the proposed method makes it possible, compared with prototype: - to reduce the loss of sugar with molasses due to better stabilization of the density of the massecuite at the output of the mixer; - automatiser is to control the concentration of solids in the massecuite inlet and outlet of the mixer. Method for automatic control and management of the preparation process of the massecuite to crystallization by cooling, providing for the regulation of the volume flow of water into the mixer and level of massecuite in it, the regulation level of the massecuite in a vertical mould by affecting variable frequency drive massequite pump, including periodic laboratory monitoring of the density of the finished massecuite at the exit of the mixer, characterized in that it further measure active electric power consumed by the electric drive massequite pump, temperature and pressure massecuite entering the mixer, the water temperature at the inlet to the mixer, calculate the density of water at its temperature and density of the massecuite by its pressure drop, calculate the volume flow of massecuite entering the mixer, the measured volumetric water flow rate, the calculated values of water density and massecuite and laboratory measured density of the finished massecuite, determine the dependency ratios of the active electric power from the volumetric flow of massecuite and the differential pressure N=α1Q3 yΔPy+α2QyΔPy, where N is the active electrical power; Qy- volume flow of massecuite in the mixer; α1that α2are coefficients and use this relationship for the subsequent calculation of the volume flow of massecuite only on the measured values of active electric power and pressure drop of the massecuite, determine the current setting of the slider of the volume flow of water based on the measured values of the flow rate, the calculated values of the density of the massecuite, the water and the volumetric flow of massecuite, the set value of the density of the finished massecuite and set the regulator calculated at the previous step control, control the content of dry substances in the source massecuite on its density and temperature, in the finished massecuite volume costs and density of the source of the massecuite and the water and the solids content in the source massecuite.
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