Processing of carbon steel furnace dusts
US5082493A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1991 |
| Grant date | Jan 21, 1992 |
| Priority date | — |
| Expiry date | Apr 26, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
In a process for the hydrometallurgical treatment of electric arc furnace dusts which includes an acetic acid leach, the acetic acid solution used to perform the leach is made strong enough to dissolve heavy metal residues in the dusts, the iron-containing residues of which are recycled to a steel producing furnace. Zinc and other heavy metals are precipitated from hot acetic acid solution as useful products by the use of hydrogen sulphide. Calcium is then precipitated from the acetic acid solution as a clean gypsum using a deficiency of sulphuric acid, thus avoiding leaving sulphate ions in solution in sufficient concentration to interact with the dust and form sulphates in the iron containing residues when the acetic acid is recycled to the leaching step.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.