Raw scrap powders containing 10 wt.% In were recovered by sand-blasting chamber shields of sputter coaters and used as a sole source of indium components for both sieving and air-classification. Sieving was performed ...Raw scrap powders containing 10 wt.% In were recovered by sand-blasting chamber shields of sputter coaters and used as a sole source of indium components for both sieving and air-classification. Sieving was performed first as a feasibility test, and enrichment of indium component was possible up to 19 wt.% with a mesh size of 635. With this experimental basis, the raw scrap powders were air-classified into 12 lots according to the revolution per minute （r/min） of a single horizontally arranged classifying wheel： 4000, 6000, 8000, 10000, 12000, and 14000 r/rain. The particle cut size varied from 56 to 5 μm with turbo wheel speeds corresponding to 4000 to 14000 r/min, respectively, and enrichment of indium component was possible in fine overflow fractions at all turbo wheel speeds while the indium components were not concentrated in all of the coarse underflow fractions. The grade of the indium components became higher with decreasing particle size of the air-classified scrap powders, with the highest grade obtained in the fine overflow fraction with a turbo wheel speed of 14000 r/min. The amount of indium in the fine overflow fractions varied between 15.9 wt.% and 31.5 wt.%. All in all, the grade or purity of the indium component improved rather significantly from 15.9 wt.% to 31.5 wt.% by air-classification, but this also resulted in overall decrease in recovery rate from 99.33% to 49.64%. Therefore, enrichment and separation of indium should be optimized for maximum recovery and grade of the indium components, which can be used as raw materials in the subsequent electro-refining processes.展开更多
Residence time distributions （RTDs） in horizontal fluidised beds have a huge effect on solid product properties and are infuenced by the internal design of the apparatus, e.g. the separation into different compartme...Residence time distributions （RTDs） in horizontal fluidised beds have a huge effect on solid product properties and are infuenced by the internal design of the apparatus, e.g. the separation into different compartments by weirs. Weirs can be passed in or against the overall solid transport direction, with the back-flow resulting in axial dispersion, which is a measure of the spread of the RTD. Therefore, the ratio of exchange rates at weirs under different fluidisation conditions provides information on axial dispersion. In this work, a methodology based on particle tracking velocimetry is presented to obtain information on the exchange rates of particles at weirs in horizontal fluidised beds. The internal recirculation is studied for over-flow weirs with respect to different fluidisation conditions, providing a first step towards determining the effects of weirs and fluidisation conditions on axial dispersion and RTDs in horizontal fluidised beds.展开更多
文摘Raw scrap powders containing 10 wt.% In were recovered by sand-blasting chamber shields of sputter coaters and used as a sole source of indium components for both sieving and air-classification. Sieving was performed first as a feasibility test, and enrichment of indium component was possible up to 19 wt.% with a mesh size of 635. With this experimental basis, the raw scrap powders were air-classified into 12 lots according to the revolution per minute （r/min） of a single horizontally arranged classifying wheel： 4000, 6000, 8000, 10000, 12000, and 14000 r/rain. The particle cut size varied from 56 to 5 μm with turbo wheel speeds corresponding to 4000 to 14000 r/min, respectively, and enrichment of indium component was possible in fine overflow fractions at all turbo wheel speeds while the indium components were not concentrated in all of the coarse underflow fractions. The grade of the indium components became higher with decreasing particle size of the air-classified scrap powders, with the highest grade obtained in the fine overflow fraction with a turbo wheel speed of 14000 r/min. The amount of indium in the fine overflow fractions varied between 15.9 wt.% and 31.5 wt.%. All in all, the grade or purity of the indium component improved rather significantly from 15.9 wt.% to 31.5 wt.% by air-classification, but this also resulted in overall decrease in recovery rate from 99.33% to 49.64%. Therefore, enrichment and separation of indium should be optimized for maximum recovery and grade of the indium components, which can be used as raw materials in the subsequent electro-refining processes.
文摘Residence time distributions （RTDs） in horizontal fluidised beds have a huge effect on solid product properties and are infuenced by the internal design of the apparatus, e.g. the separation into different compartments by weirs. Weirs can be passed in or against the overall solid transport direction, with the back-flow resulting in axial dispersion, which is a measure of the spread of the RTD. Therefore, the ratio of exchange rates at weirs under different fluidisation conditions provides information on axial dispersion. In this work, a methodology based on particle tracking velocimetry is presented to obtain information on the exchange rates of particles at weirs in horizontal fluidised beds. The internal recirculation is studied for over-flow weirs with respect to different fluidisation conditions, providing a first step towards determining the effects of weirs and fluidisation conditions on axial dispersion and RTDs in horizontal fluidised beds.
