发明名称 |
Process for filter aid production in alumina refineries |
摘要 |
An improved process for the production of tricalcium aluminate (TCA) filter aid for use in an alumina refinery is described. Quicklime is slaked in a slaker tin using a suitable slaking solution to form a slaked lime slurry ( 10 ). A suitable surface-active agent is added to the slaking solution prior to slaking of the lime. Alternatively, the surface-active agents can be added to the slaked lime either during slaking or after slaking. The slaked lime slurry is then transferred to a stirred storage/transfer tank ( 12 ) before it is pumped to a lime aging tank ( 14 ). A concentrated Bayer liquor and steam are added to the tank ( 14 ) to provide a caustic aluminate solution that reacts with the slaked lime. Sufficient residence time is allowed in the lime aging tank ( 14 ) for the initial product of the reaction to "age" before use, forming relatively pure particles of the thermodynamically stable TCA. The addition of a suitable surface-active agent or agents at the appropriate concentration will significantly improve TCA formation in the lime aging facility. These improvements include a narrower and more symmetric sized distribution, and a more crystalline structure, leading to substantially improved filtration characteristics.
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申请公布号 |
US7192568(B2) |
申请公布日期 |
2007.03.20 |
申请号 |
US20030333211 |
申请日期 |
2003.07.31 |
申请人 |
WORSLEY ALUMINA PTY. LTD. |
发明人 |
ROSENBERG STEVEN P.;WILSON DARREL J. |
分类号 |
C01F7/06;B01D37/02;C01F7/16;C01F7/47;C04B35/44 |
主分类号 |
C01F7/06 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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