Lime Furnace Thermal Process Simulation And Intelligent Integration Control

At present shaft furnace is widely used to product lime and obtain carbon dioxide inindustry. As it is difficult to determine some importan technical parameters and operatingcondition of lime sintering, production processes can not be understood accurately andcofltrOlled automatically. According to the actual condition of lime fumace, in this thesisnumerical simulation technology and new intelligent integration control idea are used tosolve the problem of combustion control in lime furnace.According to the theory of heat and materials balance, the theoretic model of cokecombustion and lime decomposition was established. The pre-heating process of mixed feedand cooling process of hot lime were investigated and theoretically analyzed. On the basis ofthermal analysis of the technical processes, a numerical model of reaction and heat transferin lime fumace was developed. Based on various parameters monitored and measured onsite, compllter simulation is carried ollt to find ollt the height of preheating zone,calcinations zone, cooling zone, and calcining status, decomposition ratio .etc. The impact ofparameters on lime stOne calcining has been studied.By adding new instruments and integrating the results of numerical simulation andmeasurements, the online information of production process in lime furnace was sufficientlycollected. By using thermal and reaction dynamics principles and fully collecting operationexperience, the control model of lime furnace was studied and expert repository wasestab1ished. Online diagnosing model and software of operation conditions of lime furnacewere aIso developed. According to the decomposition rate, temperature distribution, andonline diagnosing resultS of operating statUs, control strategy of fiJrnace operation wasdecided.Based on computer simulation and parameter measurements fuZZy and expert controlsystems were adopted, and funy intelligent controller was developed to integratemathematical model and experience of operators into control techniques to realize high-level control, which was difficult to attain before.After the control system was put into practice, the quality of lime, CO2 concentration and productivity were distinctly increased as a result of effective and steady operation of lime furnace, and thus, the target of increasing production and decreasing expense was realized.