New model of the sintering process

Abstract

Dimensional analysis is used to construct a new mathematical model that establishes a closer relationship between the unit productivity of a sintering machine and the parameters of the sintering operation. An analysis is performed to determine how the unit productivity of the sintering machine is affected by the total gasdynamic resistance of the bed, the coarseness of the material being sintered, the unit load complex, and the duration of the sintering operation. gasdynamic resistance of the bed, duration of the sintering operation, height of the bed, bulk density of the charge, coarseness of the material. Modern sinter plants are a complex system of different types of equipment that operate in different regimes and have different technological functions. The growth of sinter production is being accompanied by intensification of the auxiliary and production operations that are performed. The overall increase in sinter output and a tightening of requirements on sin- ter quality and the ability of the various operations to be performed under flow-line production conditions are creating a good opportunity for the broad introduction of automated monitoring and control equipment. Such equipment should be developed by economics- and mathematics-based methods and should maximize the productivity of the sintering machine and make the most efficient possible use of the raw materials, fuel, and capital expenditures while ensuring a certain level of product qual- ity and protecting the environment. Automated systems developed to control sinter production should also improve the orga- nization of production operations and provide for real-time control over the production process. One tool that can be used to automate sinter production is mathematical modeling. The mathematical models which are constructed can be employed to create suitable control algorithms that can work with existing hardware and software. The unit productivity of a sintering machine is one quantitative criterion of the efficiency of the sintering process. The following are the main factors that affect the efficiency of this process: the coarseness and material composition of the material being sintered; the coarseness and quantity of fuel supplied to the charge; the charge's moisture content; the coarse- ness and quantity of undersized sinter; the coarseness and quantities of the various additives that are used; the height of the bed of charge materials on the sintering machine; the vacuum created by the exhauster; the efficiency with which the charge is mixed; the character of the charging operation and the associated segregation of different charge components; the presence of different "sublayers" in the bed of charge materials; the initial temperature of the charge. The studies (1, 2) presented a mathematical model that determines the dependence of the unit productivity of a sin- tering machine W (kg/(m 2 ·sec)) on the total gasdynamic resistance of the charge bed p (kg/(sec 2 ·m), sintering time τ (sec), bed height h (m), the bulk density of the charge ρ (kg/m 3 ), and the coarseness of the material being sintered. The last param- eter is expressed through the equivalent diameter of the balled charge d (m). The model has the form