PCT/EP2006/062691 - 1 2005P06312WOAU Description Method for controlling the performance of a roasting machine for baking iron ore pellets The invention relates to the treatment of metallurgical raw material in black metallurgy and refers particularly to the production of iron ore pellets having different material, chemical and granulometric characteristics on the roasting machine. It is known that the performance of roasting machines which are in operation is often limited by the functioning of one of the technological zones, for example by the zone for drying the green pellets or by the preheating zone upstream of the baking zone. In this context, different technological zones may be limiting zones, depending on the property of the pellets to be fed and on the quality requirements of finished production. For example, in the monograph ,,Wurmetechnische Berechnungen der Aggregate zur Sinterung der Eisenerzmetalle" ["Thermal calculations of the assemblies for the sintering of iron ore metals"] (S.W. Basilewitsch et al. ,,Metallurgija", 1979, P. 208), the principle for optimizing the work of individual technological zones of the roasting machine (P. 178) is presented, which involves maintaining the relation: G = I gi - Fj; where G is the performance of the machine, t/h; gi is the specific performance of zone i, t/h-m 2 ; Fi is the area of the i-zone, m 2 Here, the specific performance of a zone is understood to mean the performance in terms of pellets to be fed, which can ensure the thermal power of the respective zone in the execution of PCT/EP2006/062691 - la 2005P06312WOAU the predetermined work for the discharge of heat to the pellet layer or for implementing the predetermined phase and physicochemical transformations. If the performance of one of the technological zones does not correspond to the pellet quantity to be fed, PCT/EP2006/062691 - 2 2005P06312WOAU it becomes the limiting zone and limits the performance of the overall roasting machine. This source comes nearest in terms of its technical essence to the invention, but has a series of substantial defects. It does not reveal the relation between the required zone performance and the properties of the green pellets, does not make it possible to take into account the influence of parameters of a limiting zone on the work of the following zones and cannot bring the operating parameters of individual zones into relation with the final quality of the baked pellets. All these objects can be achieved solely via the application according to the invention of the mathematical model for the overall technological process. Methods for the process control of pellet baking on the roasting machine, using mathematical models (Butkarev A.P., et al.; ,,Mathematische Modelle zur Steuerung des Produktionsprozesses der Pelletherstellung auf der Fbrderbandanlage", ["Mathematical models for controlling the production process of pellet production on the conveyor belt plant"], Stahl, 2000, No. 3, P. 10-13; RU2145435C1, 10.02.2000) are likewise known. In these sources, laborious and continuous automated data acquisition relating to the work of the machine is required in order to apply mathematical models. The models themselves do not bring the temperature data, that is to say the data of the thermocouples, in the gas and air chambers over the length of the machine into relation with the temperature in the pellet layer. In this case, the data of these thermocouples are the only, albeit indirect, information which reproduces the actual thermal state of the layer. The mathematical model claimed in this invention does not have these defects because it describes PCT/EP2006/062691 - 2a 2005P06312WOAU the heat exchange in the pellet and protective layer, in the roasting carriages and in the gas and air chambers in relation to one another. In this case, the mathematical model according to the invention takes into account heat-physical, physicochemical and granulometric properties of the green pellets and the layer characteristics. It likewise makes it possible 3 to use only current information on the work of the machine on account of existing measuring and control apparatus. It is desirable to increase the performance of the roasting machine and to achieve its best economo-technical characteristic work numbers or parameters, inter alia, to lower 5 the energy costs for a predetermined quality or quantity of the baked pellets. Said technical result is achieved by means of a method according to patent claim 1, in which the maximum size of the hourly performance of the roasting machine is set according to the characteristic work numbers of the technological zone which limits the overall technological process. 10 Preferably, in this case, the limiting technological zone can be determined with the aid of a mathematical model of the technological process. Subsequently, preferably, by means of the same model, the required parameters for temperature and filtration operating characteristics can be calculated over the length of this zone in such a way that these parameters ensure the increase, the maximum possible is under existing conditions, of their work effectiveness, with a corresponding rise in machine performance and lowering of energy resource consumption. To optimize the work of the limiting zone, a mathematical model may be used which brings the temperature to be measured in the gas and air chambers into relation over the length of the machine with the calculated temperature range in the pellet layer. 20 An example of the implementation of the method according to the invention is described below. For one of the roasting machines in the Michailowsky mining and treatment combine, an arithmetic analysis of the operation of all the technological zones was set up on the basis of the current data relating to their work. 25 4 It became clear that the performance of the machine in the case of the predetermined pellet stability is limited by the heating zone which does not ensure a sufficient speed of pellet heating upstream of the baking zone. With the aid of the mathematical model, the required parameters of the temperature and filtration operating 5 characteristics for the limiting zone were determined. The result of the calculations was that the proposed changes in the type of operation in the heating zone can ensure the lowering of the specific fuel consumption by 13-15%, along with the increase in machine performance of approximately 10%. By virtue of these data, recommendations for the new type of operation of the machine were prepared, and, as a result of their 1o implementation, the actual lowering of the fuel consumption was 14.5% and the performance of the machine rose by 11%. The present invention provides a method for controlling the performance of a roasting machine for the baking of iron ore pellets having different material, chemical and granulometric characteristics, the iron ore pellets passing through various technological 15 zones in the roasting machine, the roasting machine performance being limited by a limiting technological zone, wherein the maximum hourly performance of the roasting machine is set with the aid of a mathematical model according to characteristic work parameters of the limiting technological zone, and operating parameters of the technologically limiting zone are set in such a way that the maximum hourly performance 20 of the roasting machine is achieved, wherein the mathematical model, which brings a temperature to be measured in gas and air chambers of the roasting machine into relation over a length of the roasting machine with a calculated temperature range in a pellet layer, is used to optimize the work of the limiting technological zone. The invention relates to the treatment of metallurgical raw material in black 25 metallurgy and refers particularly to the production of iron ore pellets with different properties on the roasting machine. The method involves utilizing the concept of a limiting zone of the machine and applying the mathematical model for the technological process of pellet baking. The method is implemented by determining the limiting technological zone of the roasting machine with the aid of a mathematical model. The 30 maximum hourly performance of the machine is set according to characteristic work numbers of the limiting zone, and, with the aid of the mathematical model, required and sufficient operating parameters, which ensure the maximum work effectiveness of the limiting zone, are determined. This makes it possible to achieve the best economo technical characteristic work numbers of the roasting machine in the production of pellets 35 having the predetermined properties.