ABSTRACT

Release analysis is used to characterize the cleaning ability of coal fines. It defines the limit of separation at any target level of ash. Since flotation depends upon many factors like feed size and its composition, surface properties, and type of reagents, it is important to characterize the optimum boundary of separation. Release analysis following the BS7503 procedure was used to characterize a − 0.5 mm composite feed and three sized feeds, i.e., −0.5 + 0.25, −0.25 + 0.1, and −0.1 mm using different reagent combinations. Coal response reflected by release curves and corresponding batch flotation results for various reagent combinations was found to be different for all three feeds. No single combination of collector and frother could deliver the maximum separation over the entire clean coal ash range for all three feeds. Significant yields ranging from 35% to 86% could be obtained at the 13% to 17% ash level for the medium volatile metallurgical coal investigated. Release curves and subsequent batch flotation results were found to be sensitive to feed size, feed size distribution, and reagent combination types with their corresponding dosage indicating that the clean coal ash requirement would dictate the application of reagents. The investigation results further show that release analysis results can be reproduced by batch flotation.

摘要

释放分析用于表征煤粉的清洁能力。它定义了任何目标灰分的分离极限。由于浮选取决于许多因素，如进料尺寸及其组成、表面性质和试剂类型，因此表征最佳分离边界非常重要。遵循 BS7503 程序的释放分析用于表征使用不同试剂组合的 - 0.5 mm 复合进料和三种尺寸的进料，即 -0.5 + 0.25、-0.25 + 0.1 和 -0.1 mm。发现不同试剂组合的释放曲线和相应批次浮选结果反映的煤响应对于所有三种进料都是不同的。收集器和起泡剂的单一组合无法为所有三种进料在整个洁净煤灰范围内提供最大分离。对于所研究的中等挥发性冶金煤，在 13% 至 17% 的灰分水平下可以获得 35% 至 86% 的显着产量。发现释放曲线和随后的批次浮选结果对进料粒度、进料粒度分布和试剂组合类型敏感，其相应的剂量表明清洁煤灰的要求将决定试剂的应用。调查结果进一步表明，释放分析结果可以通过批量浮选重现。和试剂组合类型及其相应的剂量表明清洁煤灰要求将决定试剂的应用。调查结果进一步表明，释放分析结果可以通过批量浮选重现。和试剂组合类型及其相应的剂量表明清洁煤灰要求将决定试剂的应用。调查结果进一步表明，释放分析结果可以通过批量浮选重现。