Intensification of steel-smelting production results in the necessity of creation of the systems of automatic conduct of melting, not only automation but also optimization of executable technological operations enters in the function of which. And if at production of poluprodukta the burst performance, at the receipt of the set chemical composition became dear enough raskyslytely is used, ferro-alloys and modifiers, is mainly required, that destroys on the first plan of the system of minimization of prime price of vnepechnoy treatment.
At multicomponent composition of metal and alloying and wide set of the regulated elements master is unable to analyse all possible variants of the use of raskyslyteley and alloying materials at a plum in a scoop and vnepechnoy treatment of metal and to provide their rational use with the purpose of output on the lower (or set) limits of maintenance of elements in the prepared metal at minimum expenses.
The existent control systems are used, as a rule, the linear models of the ideal mixing with the fixed coefficients of mastering (carbon-monoxide fumes) of ferro-alloys do not take into account dependence of mastering of elements from current physical and chemical status of the system metal-slag (composition and okyslennost' metal, composition and amount of slag, temperature and etc). The mutual influencing of elements (for example, raskyslyteley on the redistribution of elements between a metal and slag) is not thus taken into account, influencing of mass and osnovnosty slag, and, does not allow to optimize shlakoobrazuyuschye addition.
The theoretical calculation of matrix of differential coefficients of mastering (DKU) is the of principle decision of this task, being the change of the masses of elements in a metal at addition of any other element. Account of the mutual influencing of elements
DKU settle accounts from the current distributing of elements in bath (between a metal, slag and other phases), and allow strictly to calculate influence of every material on composition of metal and slag taking into account the okyslennosty system, mutual influencing of elements, moment of his input in steel-smelting bath and etc In order to find the sought after matrix DKU, I.e. calculate proper derivative, it is necessary to know the type of functional dependence of the masses of elements in a metal from the masses of elements in the system.
This dependence exists, is simply solvable, however in an obvious kind she is absent, here the masses of elements in a metal are calculated on set the masses of elements in the system as a result of decision of the system of equalizations linking them . Yskomye derivative can be found from the system of equalizations either directly (by numeral differentiation, that is very difficult, as requires the decision of the system of equalizations with ever-higher exactness) or analytically, here in general case it is the task of differentiation of the system of functions of many variables set in a non-obvious kind.
The states derivative from equalizations are an important element. In the developed model for the calculation of coefficients of activity of components of metal the theory of subregular solutions is used, and coefficients of activity of components of slag is theory of the regular ionic solutions V.Kozheurova and theory of the subregular ionic solutions G.Mihailova taking into account the additional deposit of energy of mezofaznykh transitions. Exactly the these derivative act determining part at the calculation of desul'furyruyuschey ability of shlakoobrazuyuschykh materials, therefore attempt of authors to «simplify» the system of equalizations due to the waiver of account of influencing of coefficients of activity on DKU have only cleanly academic interest and can not be used for practical calculations.
Give DKU rich information for the analysis. For example, from the silicon entered in the system in a current point, 31% passes to the metal, and other in a slag, however lost this silicon is not «for free». Introduction in the system causes 1 kg of silicon redistribution of other elements — there is considerable transition of one elements from a slag in a metal (1.0 kg of iron, 0.8 kg of manganese, 0.4 kg of chrome and other), and other — from a metal in a slag (0.11 kg of oxygen leave from a metal, I.e. there is raskyslenye of metal). In addition, it is possible to watch after the use of elements of concrete material . For example, 1 kg of ferrosylykokhroma contain 0.42 kg of chrome only, but due to raskyslytel'nogo and restoration action of silicon gives the increase of maintenance of chrome in a metal on 0.47 kg, almost the same, as well as ferrokhrom (0.55 kg), in spite of the substantially greater ni-holding of chrome in the last (0.67 kg). In other words, extraction of chrome from ferrokhroma makes 82%, and from ferrosylykokhroma — 112% (I.e. exceeds in 1.36 ðàçà!). The Shlakoobrazuyuschye elements behave in accordance with the known dependences: a lime (I.e. CaO) reduces maintenance of sulphur in a metal, and SiO2 – promotes.
By the of principle difference of the offered method from yzlozhennykh in there is the method of calculation of sizes and Dij . It is considered in the known models, that , and all cross KU (I.j) is equated to the zero, that eliminates possibility of account of the mutual influencing of components or even impossibility of optimization.
High-quality a new information contained in sizes and , allows on principle to extend possibilities of optimization of alloying, raskyslenyya and affinage of metal due to the account of the mutual influencing of the elements contained in the system, on composition of metal. Influencing of the elements contained in a metal is thus taken into account not only, but also influencing of composition of slag, for example, on distributing grey phosphorus. Optimization becomes possible not only by iaoaeee-combing of part of heaping up or alloying additions but also non-metal (shlakoobrazuyuschykh) materials (used, for example, for desul'furatsyy, de-fosforatsyy, direct alloying) which in this case formal by nothing differ from metallic materials. These tasks are decided in none of the existent systems of optimization of alloying.
In spite of the got results, the DKU «capacity» in the kind resulted higher arranges not always, as the decision of task of receipt of the set ravnovesnogo composition of metal in the closed system is examined in them, that small corresponds to the terms of the real production.
Iaiie from substantial problems not finding while strict decision, there is the known fact of dependence of eventual composition of metal and slag from the sequence of input in bath of the same prospects and the masses of raskyslyteley and uglerodsoderzhaschykh materials alloying, in particular case,. It does not allow strictly to expect and find the optimum decision at the use as basis of ravnovesnoy model .
For the decision of the indicated problem it is suggested to expect DKU for every stage (period) of alloying, for example, on motion of filling of scoop. In this case allow DKU to analyse the mutual influencing of elements and watch after the use of elements of concrete material depending on the moment of his input in bath .