YUAN Yi1, HUANG Fang2, LIU Hua-long, LIU Shi-rong4, MA Hai-zhu
(1. School of Materials and Metallurgical Engineering, Guizhou Institute of Technology, Guiyang 550003, China;
2. College of materials and metallurgy, Guizhou University, Guiyang 550025, China;
3. CPI Wuchuan Alumina Branch of Guizhou Zunyi Industry Development CO., LTD, Zunyi 564300, China;
4. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China)
Abstract: Morphology structures of siliceous scabs in the process of high pressure digester is studied by technological mineralogy methods for theroretically preventing and controlling. Results show that siliceous scabs in single tube preheater are fine granular sodium silicon slag, with filling in gaps between neat and bulky hematite crystals by alumogoethite. Siliceous scabs in autoclave are small quantity of fine granular sodium silicon slag, and coprecipitate between local interlayers in the first sedimentary cycle of Ti with magnesium hydroxide matrix. Siliceous scabs in stay ladle are mainly hydrated garnet and olivine with micro-fine particle, filling in goethite crystal clearance, accompanied by a small amount of needle sodium carbonate and sodium silicon slag, while siliceous scabs in flash type evaporator are mainly iron garnet and Na2Ca3Si3O10 Phase. The former, a filler content, is symbiotic with Al2O3 (Al2O3·3H2O), and the latter, a fine granular, blends with Al(OH)3 as the main ingredient in spherulitic and layered structure respectively.
Key words: high pressure digestion; siliceous; scab; morphology structure
ACTA MINERALOGICA SINICA Vol. 34, No. 3, 2014, Page 421-426
