Objective
UM has developed a process for the inertisation and solidification of Goethite on bench scale. The product (Graveliet) can be used as a secondary constructiion material. It is the goal of this project to further develop this technology on pilot scale. These pilot experiments must allow to optimise the mixing-extrusion-curing technology and to prepare a sufficient amount of samples for constructional and ecotechnical evaluations.
The 2 major technologies used for Zn refining are the Imperial Smelt Furnace technology (ISF) and the Roast-Leach-Electrowinning process (RLE). The most important environmental disadvantage of the RLE process is the production of an Iron (Fe) waste residue (also the ISF technology produces an Iron waste in the form of a slag). UM uses the Goethite process for iron removal while most of the competitors use the Jarosite process. This iron waste is stockpiled in so-called mono-deposits or ponds. UM has developed a process for the inertisation and solidification of Goethite on bench scale during 1995 and 1996. This process consists in mixing goethite with basic slag from the steel industry. This slag contains an excess of free and reactive CaO and is also a waste problem for the steel industry. During mixing and further curing pozzolanic reactions take place between the acidic Goethite and the basic slag and the product cures into a hard and inert kind of rock. This rock has been thoroughly evaluated for its ecotechnical and constructional properties by external laboratories. The rock which is completely inert can replace gravel in concrete. By the year 2005, Flanders will have a shortage of natural gravel because the gravel winning in the valley of the river Meuse will come to an end. The Graveliet process is a low cost and low energy consuming process and can be regarded as a unique solution for the Iron waste problem in the zinc industry. Other more expensive, more energy consuming and academpic solution exist but most of these solutions do not solve the stockpiling problem of the iron waste. These pilot experiments must allow to optimise the mixing-extrusion-curing technology and to prepare a sufficient amount of samples for constructional and ecotechnical evaluations.
Topic(s)
Data not availableCall for proposal
Data not availableFunding Scheme
CSC - Cost-sharing contractsCoordinator
2250 Olen
Belgium