Blast furnace gas network of iron and steel works as an object of control

Blast furnace gas network of iron and steel work was analyzed in the article. The network comprises a collector and pipe lines, supplying gas from five and taking off gas from the collector towards blast stoves units of the corresponding blast furnaces, two gas consumers and also the unit of vent and popping of surplus gas. The parameters of incoming and outgoing gas are constantly changing in such network, it causing pressure fluctuations inside the collector. The objective of control over such network is to stabilize blast furnace gas pressure in the collector under conditions of constant fluctuations of flows on its input and exit. To solve this problem it is necessary to represent the network of blast furnace gas as an object of control, its input values being the parameters of gas flows (pressure and consumption) on the input and output of the common collector, gas pressure inside the collector being the output value. The rate of alternation of gas mass in the collector was determined on the basis of balance of mass gas flows on the input and output of the collector. A differential equation, connecting the rate of pressure alternations in the collector with its mass incoming and outgoing flows was developed by means of transition from the rate of gas mass in the collector to alternations of its pressure. A similar equation was obtained for volume gas fluxes. With application of the value of hydraulic resistance of appliances, regulating gas flows in the corresponding pipe lines a differential equation, connecting the rate of gas pressure alternations in the collector with gas pressure in the supply and lateral pipe lines. Thus, the object of control was represented in the form of differential equations, one of them describing the rate of gas pressure alternations in the collector from the bulk amount of incoming and outgoing gas flows, the other –from gas pressure in those flows. The obtained equations make it possible to analyze alternations of pressure in the collector, under the influence of various types of network disturbances and the results of such analysis can be used for development of efficient systems of automatic stabilization of network functioning