European andalusite purified by original processes and industrial testing as high quality refractory
Until this project was undertaken there was no real research being done by producers and users of andalusite concerning low iron coarse grain andalusite. Several processes were tested at the laboratory in order to purify coarse grain European andalusite. Very good technical results were achieved. One purification process (Roasting + HGMS) was tested in a pilot plant. The results were as good as those achieved at the laboratory, dealing with iron content and yield. Several hundred tons of new coarse grain andalusite were produced at the pilot plant. Four European refractorists have produced several hundred tons of new low iron andalusite refractories (bricks and castables). All the new andalusite refractories produced, gave good technical results at the laboratory. Then several hundred tons of new andalusite castables and bricks were tested in industrial conditions of a European steel plant. Technical and economical results do not seem interesting for steel ladles (when calcium oxide is high in the slag) and torpedo cars. But lining the bottom of some tundishes with low iron andalusite castable could present interest. The new low iron andalusite refractory presents a very good resistance to carbon monoxide attack. This could be interesting for special parts of blast furnace. Other refractory users (ceramic industry, glass industry) may be interested by these new low iron andalusite refractories.