Institute of Physical Chemistry, Bulgarian Academy of Sciences, Sofia, Bulgaria.
Waste Manag Res. 2011 Oct;29(10):1078-89. doi: 10.1177/0734242X10379494. Epub 2010 Aug 10.
Fly ash from three coal-burning power plants in Bulgaria: 'Maritza 3', 'Republika' and 'Rousse East' were subjected to wet low-intensity magnetic separation. The tests were performed at different combinations of magnetic field intensity, flow velocity and diameter of matrix elements. It was found that all parameters investigated affected the separation efficiency, but their influence was interlinked and was determined by the properties of the material and the combination of other conditions. Among the fly ash characteristics, the most important parameters, determining the magnetic separation applicability, were mineralogical composition and distribution of minerals in particles. The main factors limiting the process were the presence of paramagnetic Fe-containing mineral and amorphous matter, and the existence of poly-mineral particles and aggregates of magnetic and non-magnetic particles. It was demonstrated that the negative effect of both factors could be considerably limited by the selection of a proper set of separation conditions. The dependences between concentration of ferromagnetic iron in the ash, their magnetic properties and magnetic fraction yields were studied. It was experimentally proved that, for a certain set of separation conditions, the yields of magnetic fractions were directly proportional to the saturation magnetization of the ferromagnetic components of the ash. The main properties of typical magnetic and non-magnetic fractions were studied.
来自保加利亚三个燃煤火力发电厂的粉煤灰（“Maritza 3”、“Republika”和“Rousse East”）进行了湿法低强度磁选。测试在磁场强度、流速和基质元素直径的不同组合下进行。结果发现，所有研究的参数都影响了分离效率，但它们的影响是相互关联的，取决于材料的性质和其他条件的组合。在粉煤灰特性中，决定磁选适用性的最重要参数是矿物成分和颗粒中矿物的分布。限制该过程的主要因素是存在顺磁性含铁矿物和无定形物质，以及多矿物颗粒和磁性和非磁性颗粒的聚集。结果表明，通过选择适当的分离条件集，可以显著限制这两个因素的负面影响。研究了煤灰中铁磁体的浓度、它们的磁性和磁性分馏产率之间的关系。实验证明，对于特定的分离条件集，磁性分馏产物的产率与煤灰中铁磁体成分的饱和磁化强度成正比。研究了典型磁性和非磁性分馏物的主要性质。
