| The purpose of this thesis is to design a simulation platform for gas-solid filtration and separation, which is used to evaluate the filtration behavior of the porous metal materials being used in dusting in gas. In the paper, the dusting in the working order conditions was simulated to reflect the principles and mechanisms of filtration and separation. It is a experimental and measuring platform to judge filtration behavior and material properties for porous metals, which can provide the data for the design, technology and applications of metal porous materials.The simulation platform consists of the control system, filling system, filtration system,cleaning system and detection system. The main parameters are: 1) Design pressure: 1MPa; 2) Operating pressure: 0.4MPa; 3) Working medium: nitrogen or air; 4) Operating temperature: room temperature; 5) Filter material: stainless steel / glass steel, pipes 3×Φ60×300, tablets 3×Φ300.Simulation platform is controlled by PLC automatic system, whose functions are as follows: 1) adding contaminant dust and controlling flow rate; the contaminant through the spiral feeder is uniformly fed into the mixture tank, in which the volume of dust and feed rate are controlled by adjusting inlet valve; the value of gas flow in the computer-controlled interface settings valve. 2) Filtration pressure drop can be tested and recorded online, and the blow back is controlled by computer. 3) The statistical analysis of the filtration efficiency and the test of the cleanliness of the air filtration. The total filtration efficiency of the filter was obtained by weighing method, and the particle size distribution of dust before and after filtered was tested, by which the efficiency corresponding to some filtration grade of the filters was calculated; the number of the dust particles in the filtered clean gas on tested by the laser particle counter detection is characterized as cleanliness.In this experiment, the AISI 316L was chosen as the filter medium and the filtering grade was 10μm; two kinds of stainless dust with different particle size distribution were used in this test: the first group is dust particle size range of 0～100μm, 50μm in average particle size and the second group is dust particle size range of 0～50μm, 20μm in average particle size. By which the filter behavior is tested and evaluated. The results show that the dust more than 10μm in particle size can be completely blocked by filter of10μm in grade and the total filtration efficiency can achieve more than 99%.Also, the effects of gas flow, filtration time and dust concentration in gas on the filtration efficiency of porous metals are analyzed. The results showed that the filtration efficiency of the metal porous filter decreases with increasing gas flow and increases with increasing filtration time and with the increases of dust concentration because of the formation of the cake. |
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