Method for co-producing alumina and activated calcium silicate from high-alumina fly ash
US9139445B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 2013 |
| Grant date | Sep 22, 2015 |
| Priority date | — |
| Expiry date | Aug 28, 2033 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01F7/30
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method for co-producing alumina and activated calcium silicate from high-alumina fly ash, comprising the steps that: high-alumina fly ash reacts with sodium hydroxide solution to obtain desiliconized solution and desiliconized fly ash; milk of lime is added to the desiliconized solution to obtain activated calcium silicate; limestone and sodium carbonate solution are added to the desiliconized fly ash to blend raw slurry, the raw slurry is baked into clinker, and sodium aluminate crude solution is obtained from dissolution of the clinker; the sodium aluminate crude solution is subjected to the processes of first-stage deep desiliconization, second-stage deep desiliconization, carbonization decomposition, seed precipitation and etc to obtain alumina. According to the invention, less material flow and small amount of slag formation are achieved, the energy consumption, material consumption and production cost are low; the extraction rate of alumina is high, and meanwhile, activated calcium silicate with high added value is co-produced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.