Deep desilication of Bayer liquors by Friedel salt
The heating of the spent liquor in shell & tube heaters provides intensive scaling of the heating surfaces with desilication product.The industrial experience shows that even while using special reagents for decreasing of scale, under appropriate content of dissolved SiO2 the DSP is precipitated anyway and the incrustations have the friable structure considerably reducing the heat transfer ratio.It has the negative impact on the heat balance and technical and economical parameters of alumina refineries.The series of different additives were studied for improvement of desilication of caustic-aluminate liquors with positive references from alumina refineries processing high silica bauxite and nephelines.Also the desilication behavior of calcium hydro chlorine aluminate (so called Friedel salt 3CaO× Al2O3×CaC12×10H2O) was tested.It was demonstrated that to compare with other identical reactants the structural modifications of Friedel salt in the heating circuit allows more effective removal of SiO2 from liquor in form of solid phase.The potential of different transition forms of Friedel salts in alumina production process was demonstrated.Their implementation in the process circuit was demonstrated in order to generate the components with low C1-ion.The proposed process helps solving the issue of incrustations resulting in significant advantages of energy and resource saving.
Bayer liquors desilication efficiency additive Friedel salt
Andrey Panov Alexander Suss.Natalia Kuznetzova Alexey Nechitaylov Irina Paromova
RUSAL Engineering and Technology Center, 199106, Sredny pr.86, St.Petersburg, Russia
国际会议
32th International Conference & Exhibition ICSOBA-2014(第32届国际铝土矿、氧化铝和铝工业技术学术年会)
郑州
英文
259-267
2014-10-12（万方平台首次上网日期，不代表论文的发表时间）