Impact of different additions on the green liquor desilication
One of the important steps of the Bayer process is achieving purity of product in terms of silica. For that one has to ensure that all soluble silica is bound into stable desilication products. Most of the alumina plants processing gibbsitic bauxites convert reactive silica (mostly kaolinitic) into DSP at pre-desilicaiton and digestion stages. For some types of bauxites with specific mineral composition the desilication process can not be completed at digestion. These are monohydrate alumina bauxites with silica represented less by kaolin but more by shamosite, epigenetic quartz, etc. The digestion of above bauxites under high caustic concentration followed by considerable dilution at precipitation conducts to the considerable variation of silica balance and problems with product purity. This paper covers RUSAL VAMI studies for green liquor desilication using additions like tricalcium hydroaluminates (TCA), calcium hydrocarboaluminates (CHCA), lime and DSPs of different structure. The method for desilication at this stage is suggested. Industrial application of said technology prior to or in combination with security filtration is discussed.
Desilication green liquor tricalcium hydroaluminate calcium hydrocarboaluminate
A. Suss I. Paromova N. Kuznetzova A Panov A.Damaskin I. Lukyanov
Sredny prospect, St. Petersburg, Russia
国际会议
XVIII International Symposium of ICSOBA(第18届国际铝土矿、氧化铝及铝工业学术年会)
郑州
英文
222-230
2010-11-25（万方平台首次上网日期，不代表论文的发表时间）