Modeling of automatic temperature control system in the pre-chamber of conveyor roasting machine

Abstract

The article considers the modeling of the automatic temperature control system for waste gases in the pre-chamber of the hearth of a conveyor roasting machine. For heat treatment of pellets it is necessary to determine the physical and chemical properties of the boilers and their mass, which makes it possible to calculate the optimum treatment temperature in the zones of the aggregate. The purpose of the article is to model the system of automatic temperature control in the pre-chamber of the roasting machine which will ensure compliance with the temperature regime, taking into account heat and mass transfer reactions in the bed of pellets, since control is carried out by the value of the temperature of the waste gases. The gas consumption control and compliance with the gas-air ratio makes the best use of the energy sources. The developed system of automatic control of waste gases temperature in the pre-chamber of the hearth of the roasting machine has been simulated by means of the graphical Matlab Simulink simulation. The temperature regime is controlled by such basic parameters as the temperature of waste gases, the fuel and air consumed in its burning. Fuel control is carried out in each pre-chamber of the unit, which makes it possible to analyze the distribution of heat in the technological zones. The paper presents the existing system graphs of temperature control in the furnace and the developed system graphs of temperature control - in the pre-chamber. The studies of the temperature control system in the hearth and the developed system have been carried out, the results of which have shown that the existing system has higher gas consumption, which results in an irrational use of energy sources, and in an increase in the temperature by 2,8% in the chamber of the roasting machine. The developed system of temperature regulation in the pre-chamber maintains the set temperature, the error of which is 0,5%, for the burning of iron ore boilers when the bulk density changes and allows to reduce the gas flow by 2,7% The developed system of temperature regulation in the chamber maintains the pre-set temperature, the error being 0,5%, for the burning of iron ore boilers when the bulk density changes making it possible to reduce the gas flow by 2,7%. Automatic control of the basic parameters necessary for controlling the temperature of the operation of the roasting machine is provided, they being the temperature of waste gases, the amount of gas and air, depending on the actual mass of the boilers