| High suspension separator is new practicality equipment (patent number -. 94200555.4) in China, it set up a new investigation direction for separation fine particles. The mechanism of new investigation direction for separation fine particles were studied, which established theory of separation suspension fine particles.The main contents of thesis were divided into three parts: firstly, numerical analysis is studied for the movement of fine particles in suspension airflow in high voltage electric field; secondly, the mechanism of suspension electrostatic separation of micro-fine particles was studied; thirdly, the factors which have effect on suspension electrostatic separation were studied by experiment. The details of the thesis were shown as follow:1. Forces acted on Micro-fine particles and movement of Micro-fine particles were studied in suspension electrostatic separation. When micro-fine minerals were transported by airflow, because of the various forces acted on them, there were four movement forms possibly after being dragged: sliding, rolling, jumping and suspending. Force acting of the mineral particles in suspension electrostatic separator could be divided into three stages: vertical movement, movement in high voltage corona electric field and in electrostatic separation. The thesis studied the three stages of force acting respectively, established movement equation of the mineral particles.2. Movement of Micro-fine particles were analyzed by numerical calculation. The formula of time, formula of distance and the movement equations of no dimension were put forward, which were in the process that the mineral particles of three stages were accelerated to a stable stage.3.The finite element model of suspension micro-fine particles in high voltage electrostatic field were established by developing the large scale software ANSYS again, and a series of calculation were done. Corona electric field between electrode of suspension type electrostatic separator were calculated. The movement of suspension micro-fine particles in high voltage electric field was simulated. The results of simulation indicated: the longer the distance to corona electrode was, the smaller the electric field was, the electric field in the corona outskirt is a constant at a certaindistance. Speed distributing of micro-fine mineral particles in turbulence movement was curve of logarithm or index. The conclusions are consistent with the fact.4.The mechanisms of electroconductive discrepancy among mineral were studied. Although mineral included abundant electrons, some of the minerals are good conductor, some are non-conductor. The thesis studied electroconductive discrepancy among minerals with the energy band theroy. According to the energy band theory, the mechanisms of conduction process were described by energy level of different valence band and conducting band and among the width of the forbidden band.5.Suspension mechanisms of micro-fine particles were studied. The suspension type electrostatic separator requires that the micro-fine particles are suspending, therefore, in order to keep particles transporting, feeding and suspending in pipe normally, the speed of the particles mustn't be less than a certain value. The thesis discussed the sedimentation speed and the suspension speed of the particles, the suspension mechanism of the micro-fine particles was also analyzed.6.The microcosmic basic process of gas discharges in high voltage was studied, macroscopical phenomena was explained by microcosmic process. The gas discharges were complicated movement system of the particles. The six kinds of basic particle existed in process of gas discharges were: photonses, electrons, atoms and molecules of ground state, atoms and molecules of excitable stage, positive ions and negative ions. Any of the particles in gas discharges could produce mutual forces by collision. Particles participating in elastic collision exchanged momentum only, their potential energy did not change, they did not exchange charge; p...
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