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白钨矿浮选731捕收剂低温乳化试验研究 总被引:2,自引:1,他引:1
介绍了731捕收剂在低温条件下试验的情况。试验研究结果表明,采用A和B药剂以5:6的比例混合组成的复合乳化剂对731进行乳化,低温时乳化体系稳定性好,浮选过程中降低乳化731的用量,同时提高了选择性,降低了浮选成本,实现了低温环境下白钨矿正常浮选作业,达到选矿技术攻关指标。 相似文献
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The influence of raw material characteristics on the industrial pelletizing process and pellet quality 总被引:1,自引:0,他引:1
Mehrdad Arshadi Rolf Gref Paul Geladi Sten-Axel Dahlqvist Torbjörn Lestander 《Fuel Processing Technology》2008
Industrial pelletizing of sawdust was carried out as a designed experiment in the factors: sawdust moisture content, fractions of fresh pine, stored pine and spruce. The process parameters and response variables were energy consumption, pellet flow rate, pellet bulk density, durability and moisture content. The final data consisted of twelve industrial scale runs. Because of the many response variables, data evaluation was by principal component analysis of a 12 × 9 data matrix. The two principal component model showed a clustering of samples, with a good reproducibility of the center points. It also showed a positive correlation of energy consumption, bulk density and durability all negatively correlated to flow rate and moisture content. The stored pine was more related to high durability and bulk density. The role of the spruce fraction was unclear. The design matrix, augmented with the process parameters was a 12 × 6 matrix. Partial least squares regression showed excellent results for pellet moisture content and bulk density. The model for durability was promising. A 12 × 21 data matrix of fatty- and resin acid concentrations measured by GC–MS showed the differences between fresh and stored pine very clearly. The influence of the spruce fraction was less clear. However, the influence of the fatty- and resin acids on the pelletizing process could not be confirmed, indicating that other differences between fresh and stored pine sawdust have to be investigated. This work shows that it is possible to design the pelletizing process for moderate energy consumption and high pellet quality. 相似文献
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某铅锌矿选矿尾矿综合利用试验研究 总被引:2,自引:0,他引:2
针对选矿尾矿的特性,采用高选择性的3ACH捕收剂、F—1抑制剂,回收了绢云母含量分别达96%和64%以上的一、二级绢云母产品。经应用试验表明:绢云母一级品在橡胶中的补强性能基本达到了沉淀法白炭黑水平,二级品也全面超过硅铝炭黑的补强性能。 相似文献
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A mini spray dryer has been used to investigate morphological changes that occur to milk particles during the spray drying process. We have found that the mini spray dryer is ideal for such investigations, because phenomena such as skin and vacuole formation in particles can be analyzed without the added complication of particle agglomeration, which only occurs in much larger spray dryers where particle number concentrations are higher. We have confirmed observations made by various researchers that the bulk density of spray-dried milk powder is greatly affected by the drying temperature, due to the strong influence of the latter on the porosity of the particles. In addition, we have attempted to explain observations made by various workers that fat accumulates preferentially at the surface of a particle during drying by postulating that fluid fat is transported towards the surface, via a network of cracks and pores, by the development of a vacuole overpressure which is also responsible for the inflation of the particle. Finally, we have shown that milk powders can be spray dried a second time, by reconstitution with water, with no change to the thermodynamic characteristics of the resultant powder. Thus, milk concentrates for spray drying research can be prepared from already-spray-dried milk powders rather than using the more arduous evaporation method to concentrate unprocessed milk. 相似文献
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V. V. Tcherdyntsev S. D. Kaloshkin A. I. Salimon E. A. Leonova I. A. Tomilin J. Eckert F. Schurack V. D. Rogozin S. P. Pisarev Yu. P. Trykov 《Materials and Manufacturing Processes》2002,17(6):825-841
Al-Cu-Fe alloys were prepared from elemental powders in a high-energy planetary ball mill. A sequence of solid state reactions resulting in quasicrystal (QC) phase formation takes place during heating of the as-milled powder. These reactions were studied by both differential scanning calorimetry and x-ray diffraction methods. Mechanically alloyed powders were consolidated by cold and hot pressing, as well as by explosive compaction. After annealing at sufficiently high temperatures, the consolidated samples are single-phase QC, except the ones consolidated by explosion. The high reactivity of the as-milled alloys causes the appearance of high porosity of the consolidated samples after the annealing. 相似文献
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