Modeling And Control System Realization Of Three-Phase Circulating Fluidized Bed On Gold Extraction From Gold Concentrate

Three-phase circulating fluidized bed is a kind of reaction devices which can mix gases, liquids and solids together. Not only harmful gases can be recycled to achieve cleaner production purpose, but also reactants can be adequate mixed through the outer loop so that it can enhance reaction efficiency. Thus, it is of great significance to research and development three-phase circulating fluidized bed which can be used to gold extraction from the difficult cyanide gold resources for the achievement of clean production in gold extraction , improvement the recovery of gold and recovery of valuable metals such as silver, copper, lead, zinc and so on .To make pre-oxidation treatment of high-sulfur and high-arsenic refractory gold concentrates or cyanide tailings achieve automatically continuous and high-efficient under atmospheric pressure, the three-phase circulating fluidized bed control system of reliable and good performance are essential. Over the years, the traditional PID control is a kind of main control methods are used frequently in industry, but because three-phase circulating fluidized bed system of gold concentrate has characteristics such as non-linear, pure delay, multi-variable which make the control of reaction process face multiple complicated problems. The application of advanced intelligent control strategy is expected to achieve effective control of the fluidized bed systems, improvement of reaction efficiency and mass production economy. This paper studies the characteristics of the production process of the three-phase fluidized bed in gold extraction, then designs and develops its control system. The main duties included in this paper as the following aspects: 1,Analysis of three-phase circulating fluidized bed system features. The gas target is obtained by experimental datas measured in different fluxes circumstances in correspondence with the maximum reaction rate, and the establishment of a system model according to the internal flow characteristics by the combination of the step identification and least-squares identification method, so that dynamic mathematical models of the fluidized bed are obtained in the Circumstances of different fluxes.2,Design of a optimal PID fuzzy controller according to the characteristics of bed pressure control system, it makes the system respond fast to reach steady state, and verification of the control system simulation by using the object model.3,For the characteristics of instability in the internal object model of the actual system in the chemical reaction process, the introduction of predictive control thought to reduce the degree of model mismatch. The combination of predicted theory and fuzzy control, so that control systems can be achieved with better robustness and rapidity, then ultimately achieves the purpose of improving reaction efficiency.4,The establishment of a three-phase fluidized bed system simulation description based on Zijin Bridge configuration software platform. With Matlab as a predictive control algorithm platform, through dynamic data exchange (DDE) of two kinds software platform, achieve online predictive control, then make the predictive control algorithm such as dynamic control can be easily and accurately applied to fluidized-bed control system.5,Design and development the hardware and software of the whole control system. The control system has been applied to the gold extraction from gold concentrate reactor , then compare the data measured results before and after control systems applied by the system experiment in the thermal state,which shows that the the control system designed can improve the produce efficiency by 8.39%.The research of this paper make a close integration with new circulating fluidized bed crafts and new technology of the gold extraction from gold concentrate, and the choice of the control program is suitable for the control characteristics of the gold extraction from gold concentrate, which has important practical significance on the safe and efficient operation of circulating fluidized bed system.