PLC Intelligent Programmable Controlled Reagent-Adding System Based On Digital Image Processing Technology

Reagent-adding control is one of the important segments of mineral processing, and directly affects the technical-economic targets of the ore dressing plant. In the traditional floatation process, the apothecary controls the dosage of the floatation reagent by his own experience, and it is difficult to do it timely and accuratelly. With the development of science and technology, adopting PLC to realize programmable-control for reagent-adding has become one of the developing tendencies.In this paper, we designed an intelligent auto-control floatation reagent-adding system which is made up of Image-collection system, Image processing system, and the PLC controlled Reagent-Adding System. Also there has an introduction of measuring and choosing the flotation froth image's characteristic parameters, and from them building mathematics models of floatation's comprehensive efficiency and dosage of reagent.The reagent-adding system, which is designed in this paper, chooses PLC to manage operations, and adopts two-layer style constructions. It likes a small DCS architecture: the upper stairs are used to keep up with the supervision and administration by the industry computer, and the down stairs complete actions such as reagent-adding and warning which are charged by PLC. The dissertation makes best use of powerful STEP7-Micro/WIN32 software, VC++ 6.0 software and ControX2000 software. Respectively, we draw on STEP7-Micro/WIN32 software to make PLC realize reagent-adding performance, warning, and other commands; draw on VC++ 6.0 software to compile Image-collection system, Image processing system, Mathematics modeling system, and the communication protocol between computer and the PLC; and draw on the ControX2000 software to build the computer's supervision platform. At the same time, with the help of the three powerful softwares, we have debugged all of the programs completely.On the application of PLC programmable controlled reagent-adding system which is based on digital image processing technology, we carried out a series of small floatation experiments of sulfide-mine in the laboratory. In the experimentation, we adopted the methods of one-time-one-factor trial to the dosage of pH conditioner Na₂CO₃ and collector xanthate. We calculated some characteristic parameters of the floatation froth images which were collected in the experimentation, and chose 5 of them - including saturation, greyness, energy, entropy and moment of inertia, to build the mathematics models of floatation's comprehensive efficiency and dosage of reagent. With the help of this mathematics models, we identified and classified the images of floatation froth, and used them as the guide of PLC controlled reagent-adding system.