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Rare earth lanthanides, scandium and yttrium, a total of 17 elements. China is a big country, rare earth reserves and production ranks first in the world of rare earth resources. Rare earth elements in the display phosphors, NdFeB, nickel hydrogen batteries, rare earth aluminum alloy, precision ceramic manufacturing is an important and indispensable raw materials. With the rare earth industry in the production of large-scale, centralized and continuous urgently requires efficient, a stable automated production lines. Purification separation factor between adjacent elements, rare earth elements needed for the production of a series of extraction and separation processes. Extraction process input extractant flow, flow of solid to liquid, acid flow regulation, usually by up to several hours or even a few dozen hours of step by step transfer to affect the aqueous and organic phase difficult Crafts and ease of extraction of rare earth exports component content of the element, and any traffic changes have an impact on both ends of the export product purity, there is a nonlinear, large time delay and strong coupling element component content of the extraction process between the input flow. However, easy Crafts component and difficult Crafts component reflects changes in the distribution of the extracted slot to move around in the characteristic color of the rare earth ions. The rare earth ions characteristic color with mobile is intuitive, and can be measured. Generalized predictive control can predict the future output of the multi-step model, and multi-step time period, control how step; Fuzzy control based on fuzzy set theory, fuzzy decision-making and reasoning capabilities introduced in the control, so you can accumulated a wealth of practical experience, that the expert control rules, through fuzzy inference and defuzzification, into a precise control of the amount, in order to achieve the automatic control of the extraction process. The main work of this paper are summarized as follows: (1) a more in-depth study of rare earth extraction process. First described the rare earth extraction process, and the mechanism of the extraction process analysis; then discuss the automatic control of the rare earth extraction process; Finally, based on current research, summarized the problem of rare earth extraction technology. (2) when the extraction process conditions change, the Easy Crafts component and difficult Crafts component in the distribution of the extracted slot will vary, reflected in the characteristic color of the rare earth ions before and after the move. Video monitoring, rare earth colors with changing fast and near as monitoring points, and image processing technology, the analysis identified a band of color offset series. Experimental results show that, regardless of the rare earth ions characteristic color with forward or backward, can accurately determine the offset level. (3) access to rare earth ions characteristic color with offset, generalized predictive control and fuzzy control rare earth extraction control. Finally, the simulation results show that the two control method is effective, thereby ensuring the separation of rare earth extraction final purity of the export component content.
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