Method of controlling smelting of matte in vanyukov's furnace at discrete delayed control over melted product quality

FIELD: metallurgy.

SUBSTANCE: proposed method comprises control over copper content in matte and stabilisation of matte composition by maintaining reset melting conditions by correcting control effects. Note here that correction of said control effects is carried out continuously by compensating disturbances in discrete delayed control over copper content in matte corresponding to equivalent delay defined by mathematical expression.

EFFECT: matte quality stabilised in time and composition.

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The invention relates to the field of automation of technological processes and productions, and particularly to a method of controlling the quality of products smelting of Nickel-copper sulfide raw materials in Vanyukov furnace, and can be used in the production of non-ferrous metals, in particular when managing the quality of products melting in a melting unit with selectable delayed control of the composition of the products of melting.

There is a method of process control low-temperature deep obestsenivaya aluminate solution (A.S. SU # 1034995 D.P. from 29.05.1973). The essence of the invention consists in the following. In the reactor comes aluminate solution and the milk of lime fed from the collector. Lower level management is a local system of automatic stabilization dosage milk of lime, which consists of a flow meter aluminate solution, the flow meter lime milk, the ratio controller and the actuator that changes the flow of milk of lime. Upper level management is a computing machine that calculates the dosage of lime milk per unit volume aluminate solution according to data from the analyzer of the quality of milk of lime. In the computing machine is set to the numerical value of flint module, which should be maintained after re is Chora. The calculated dose is delivered to the ratio controller as a job.

The disadvantage of this method is the low accuracy of control and lack of responsiveness.

A known method of controlling the refining process of the metal flow in the steelmaking unit (patent No. 2017830 D.P. from 27.12.1990). The method includes measuring the costs of gaseous oxygen and natural gas, the carbon content in the liquid metal and the provisions of the blowing lances, the definition until the end of the refining process of the temporal sequence of changes in the supply of oxygen, natural gas, number of additives solid oxidizer and the provisions of the blowing lances on the basis of the error predicted for the end of the refining process temperature of the metal from its specified value. Information from the sensors is fed to the computing unit, which adjusts the amount of graphitemoderated material introduced into the working space of the steelmaking unit, depending on the magnitude of the predicted values of temperature and metal content of carbon. Computing unit depending on the error between the predicted value of the temperature of the metal and its set value changes the number of graphitemoderated material introduced into the working space stalprofil the th unit.

The disadvantage of this method is to narrow the application of this method without taking into account the discrete delayed control of the composition of the melt.

A known method of controlling the decomposition process (collection of "alumina". Proceedings of YOU, No. 77, Leningrad, 1971, str-186), which are as follows. 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, which determines 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 is erodov analysis), changes the characteristics of the control object in time (covering equipment, inlay heat transfer surfaces), uncontrolled perturbations (level change in decomposer, changing conditions of mixing, etc.)

Among the disadvantages of this method it should be noted the lack of compensation for delayed discrete control of the content of the aluminum hydroxide.

Known way to control the blast furnace (Applied fuzzy systems: Lane. with jap. Kasai. Dated. Sevai and other edited Thereno. Kasai, Magano. - M.: Mir. 1993, p.70-88). The system consists of a control computer, which collects data from sensors and their pre-processing for presentation in a form suitable for inference processor of artificial intelligence using knowledge base, makes conclusions about the heating furnace, and digital instrumentation, control heating by the results of the findings.

CPU artificial intelligence contains software support expert systems and machine findings, interpreting knowledge. The control computer, in addition to the functions of preliminary data from sensors, equipped with functions for data analysis and diagnostics of heating according to the mathematical model. On the basis of information from sensors and knowledge base in the system is done in the waters about the current level of heating period of 20 min and about the increase or decrease of heat; according to the results of the output using the control rules are determined by the amount of blast and other parameters.

The disadvantage of this method is the discrete control (every 20 minutes) basic parameter - level heating furnace, so as the temperature of the process is a factor in determining the composition of the products of melting.

Known way to control melting of copper-Nickel sulfide raw material in Vanyukov furnace (Melting in the liquid bath / Vanyukov A., Bystrov VP, Vaskevich A.D. and others / edited Avenula. M.: metallurgy, 1988, p.122-123), taken as a prototype. In this case, the smelting of copper-Nickel sulfide raw material in Vanyukov furnace lead to Stein. The purpose of the control of the smelting process of copper-Nickel sulfide raw material in Vanyukov furnace is to stabilize the copper content in the matte by stabilizing the temperature of melting. As the main parameter of the selected melting temperature, because the temperature of the process is a factor in determining the composition of the products of melting.

The calculation of the technological mode of smelting copper-Nickel sulfide raw material in Vanyukov furnace is carried out on the basis of the program of the forecast. During process control melt temperature regulate the adjustment of control actions. This trick aims to compensate the effects of various factors.

To fake who headed the remainder of the method is, first of all, low control accuracy, because the change of control actions has a very strong influence on the composition of the products of smelting, which violates the stability of the furnace, that is not provided by the specified quality matte. In addition, no provision is delayed discrete product quality control heat.

Technical task control method smelting of Nickel-copper sulfide raw materials in Vanyukov furnace at discrete delayed product quality control is melting the creation of such a control method, which is compensated discrete lagging quality control of the products of melting due to the replacement of discrete control loop continuous control system, operating in real time, which allows you to manage the process continuously and to stabilize the quality of a Stein.

The technical result of the invention is the stabilization of the quality matte in time.

The technical result of the invention is achieved in that in the method of control of the heat, copper-Nickel sulfide raw material in Vanyukov furnace at discrete delayed product quality control melting, which includes the determination of the copper content in the matte, the stabilization of the composition of the matte by maintaining a given mode of fusion due to the adjustment of governors of the impact is of textbooks, according to the invention as a main parameter take the copper content in the matte; the adjustment of the control actions carried out continuously by compensation of the amount of perturbation of the discrete delayed main control parameter corresponding to the equivalent amount of lag (τ_EQ), which is determined by the formula:

$$t_{eK\mathrm{in}}=t_{\beta }\cdot \left(1+\mathrm{0,46}\cdot {\left(\frac{T_{\beta }}{t_{\beta }}\right)}^{\mathrm{0,66}}\right),$$

where τ_β- laboratory measurements, the samples are matte; T_βthe period of sampling products.

The method of control of the heat, copper-Nickel sulfide raw material in Vanyukov furnace at discrete delayed product quality control melting illustrated by drawings, where figure 1 shows a diagram of an automated control system (ACS) process for implementing the method.

The sequence of technological processes 1 processing of materials from one state to another forms the pyrometallurgical production of 2. Information from the object enters the programmable l is logical controllers (PLC) 3, automated workplaces (AWP) operators and system data visualization (SCADA system). In addition, samples of materials and products from the process are received in the laboratory 6 for chemical analysis.

Job setpoint the process, the correction of the coefficients of the control devices, indicators of production costs, the optimal values of the process and manufacturing, technical and economic parameters and other inputs to the system are made via the manual input unit 8 in a virtual module 7 and the computer unit 5. Then it goes on a shared server 4, which is stored in the form of graphs, tables, trends, etc. There is a primary statistical processing of data, namely the data is validated against actual values screenings of random variables, addressing data gaps and other errors. The created database is sent for further processing in the computing unit 5, which is the calculation of the compensation of perturbations of discrete delayed control.

The essence of the compensation of disturbances spare wheel bracket illustrated by figure 2, which shows: 1 and 2 - clamps zero order f₁and f₂accordingly, 3 - linear model of technological process with the transfer function F_µ(jω), 4 - perturbation compensator (controller) from the front of the full-time function f _β(jω), V1 and L keys, simulating discrete operations of sampling (the delay time τ_β), µ is the control signal, ξ - signal neocomposite, β - managed value.

Compensation for delayed discrete control is carried out as follows. The closure of key KL1 and CL with the holders of the zero order f₁and f₂simulate discrete operations of sampling, input the results of its analysis in the computer memory (with delay time τ_βand implement the control action generated by algorithm f_β. Keys locked in phase and synchronous with a period of T_βsampling of products.

Including in the control system of smelting copper-Nickel sulfide raw material in Vanyukov furnace at discrete delayed product quality control melting link equivalent lag G_EQthat depends on the parameters of discrete delayed path diagram in figure 2, can be converted in the control scheme shown in figure 3, which shows: 1 - the link is equivalent to the lag, 2 - linear model of technological process with the transfer function of$${\text{F}}_{\text{μ}}^{\text{'}}\left(\text{j}\mu \right)$$3 - perturbation compensator(controller) with transfer function f _β(jω), µ is the control signal, ξ - signal neocomposite, β - managed value (matte).

Compensation of perturbations of discrete delayed product quality control melting in the management of Vanyukov process is that the control circuit smelting of Nickel-copper sulfide raw materials in Vanyukov furnace at discrete delayed product quality control melting link equivalent lag G_EQthat depends on the parameters of discrete delayed path. Asking linear operator G_EQ(s)

$$G_{eK\mathrm{in}}(s)=e^{-t_{eK\mathrm{in}}\cdot S},(1)$$

where$$t_{eK\mathrm{in}}=t_{\beta }\cdot \left(1+a\cdot {\left(\frac{T_{\beta }}{t_{\beta }}\right)}^b\right)$$(a and b are the parameters of the system) replaces the lag in the feedback circuit τ _βon an equivalent amount of lag τ_EQ; a and b are the values for when the minimum difference of the response fluctuations in the composition of matte Vanyukov process β(t) at the output of the system at the same the disturbance ξ(t).

Array processing units find a description of the dependencies of the parameters of the operator G_EQ(s) on the parameters of discrete delayed control is determined by the function

$$t_{eK\mathrm{in}}=f\left(T_{\beta },t_{\beta }\right)(2).$$

The effectiveness of quasi-system with discrete delayed control of the composition of the products of fusion is to determine the dependence of the spectral density function S_β(ω) from period T_βcircuit key KL1 and CL and parameters of the linear model of the control object, the transfer function which has the form

$$F_{\mu }^E(p)=\frac{K_{\mu }}{1+T_{\mu }\cdot p}\cdot G_{eK\mathrm{in}}.\text{(3)}$$

When this preset is a function of the spectral density S_ξ(ω) and assume that the results of discrete measurements of the composition of the matte is converted into control actions. In this case, it is advisable to use a PI controller with transfer function:

$$F_{\beta }\left(j\omega \right)=K_p+\frac{1}{j\omega \cdot T_p},\text{(4)}$$

where K_pand T_p- the settings of the controller.

Thus, to obtain the transfer function f_β(jω) to compensate for perturbations of discrete delayed control in the management of smelting copper-Nickel sulfide raw material in Vanyukov furnace at discrete delayed product quality control melting, you must:

1. To determine the estimated or experimental method the parameters of the control object (Vanyukov furnace).

2. To determine the parameters of discrete delayed control, that is, to set forth Amazon practically possible values of the period of sampling matte T _βand laboratory measurements, the samples matte τ_β.

3. To calculate the equivalent link delay G_EQby the formula (1) and the transfer function of the control object by the formula (3).

4. To calculate the settings of the regulator with regard to the level equivalent to the delay by the formula (4).

After this mathematical apparatus continuously receives the request to process control to improve the control accuracy, which in turn leads to the stabilization of matte composition. This cycle of the calculation for a period of sampling is completed. For the next period of the sampling cycle is repeated again.

For the implementation of the proposed control method smelting of Nickel-copper sulfide raw materials in Vanyukov furnace at discrete delayed product quality control melting first, you need to take a range of values of T_βand τ_βand the number N of points in this range, which will be optimized control object and identified the operator G_EQ(s).

Example 1

For Vanyukov furnace PV-2, operating at the Copper plant of the polar division of OJSC MMC Norilsk Nickel, which is the pyrometallurgical object with discrete delayed control of the composition of the products of fusion (matte), defined write expressions for calculating quivalente lag τ _EQ:

$$t_{eK\mathrm{in}}=t_{\beta }\cdot \left(1+\mathrm{0,46}\cdot {\left(\frac{T_{\beta }}{t_{\beta }}\right)}^{\mathrm{0,66}}\right)$$.

Thus, the analytical form of the expression for τ_EQthat link is equivalent to the lag G_EQand functions of the spectral density of fluctuations depending on the parameters of the control object (the period of sampling matte T_βand laboratory measurements, the samples matte τ_βand spare wheel bracket allows you to create a continuously operating control system when replacing open loop control (figure 2) closed (3), which leads to stabilization of the quality of matte and optimization of process control.

The method of control of the heat, copper-Nickel sulfide raw material in Vanyukov furnace at discrete delayed control the quality of products smelting, including the control of the copper content in the matte, the stabilization of the composition of the matte by maintaining a specified mode of the heat by adjusting the control actions, wherein the adjustment control actions carried out continuously by compensatively perturbations of discrete delayed control the copper content in the matte, the corresponding equivalent amount of lag (τ_EQ), which is determined by the formula:
$$t_{eK\mathrm{in}}=t_{\beta }\cdot \left(1+\mathrm{0,46}\cdot {\left(\frac{T_{\beta }}{t_{\beta }}\right)}^{\mathrm{0,66}}\right)$$
where τ_β- laboratory measurements, the samples are matte;
T_β- period of the sampling matte.