The ISASMELT™ team are constantly researching and developing new and improved processes. The latest innovation with the ISASMELT™ technology is continuous copper converting. The ISACONVERT™ process offers an alternative to batch copper converting operations, such as Peirce-Smith (P-S) converting. It is an attractive option due to its flexibility to treat solid feed and efficiently capture SO2 and reduce in-plant fugitive emissions.
Modelling and experimental studies conducted by the CSIRO in collaboration with Xstrata and extensive pilot scale testing conducted by Xstrata Technology has confirmed that continuous converting of copper matte can be achieved to produce blister for anode furnace refining. The majority of pilot scale testing focusses on converting crushed copper matte produced in the ISASMELT™ smelting furnace. This two stage smelting and converting process is being considered for installation at a number of copper smelter sites.
The process is very easy to operate and is autogenous with combustion air enriched to approximately 30% oxygen. Solid feed combined with the high level of oxygen enrichment produces a low volume of offgas, rich in SO2.
Advantages of ISASMELT™ continuous converting are:
- Low capital cost compared with multiple batch furnace applications. The saving is due to:
- the reduced size and number of furnaces;
- easier hygiene ventilation from the smaller plant;
- elimination of the expensive converter aisle crane system; and
- a smaller size acid plant is needed with continuous flow of converting gas from the ISACONVERT™ furnace.
- Smelting and converting operations can be decoupled by a matte stockpile, alleviating the need for a matte holding furnace, and allowing independent operation of the two furnaces. This will remove a production bottleneck and increase availability significantly.
- Very low dust production and generation of a low volume of offgas, rich in SO2 gives greater environmental control than other available technologies.