PRODUCTION OF SPINEL FORSTERITE REFRACTORIES USING SHEARED SERPENTINIZED ULTRAMAFIC ROCKS, UM SELEIMAT, EGYPT

Abstract

The present work aims at assessment and utilization of some Egyptian Sheared serpentinized ultramafic rocks, from Um Seleimat ophiolites at Central Eastern Desert (CED), for producing refractory forsterite and spinel forsterite composites. Generally, Egyptian serpentinized ultramafic rocks occur in two types, massive and sheared serpentinites. To perform the study aim, two batches were designed on base of stiochiometrical calculations of specific proportions of “used magnesia” and/or “calcined bauxite” in addition to the serpentinized ultramafic rocks and fired at 1500oC for two hours to form forsterite and spinel forsterite. Chemical and mineralogical studies were carried out for the starting materials, while mineralogical composition, scanning electron microscope, EDAX as well as physical parameters and thermo-mechanical properties, are done for the fired batches. In addition, the compressive strength as well as the refractoriness under load was done. The study results indicated that forsterite and spinel composites were produced from serpentinites by adding a calculated amount of used magnesia and/or calcined bauxite mixed to the studied sheared serpentinized rocks. Based on the previously measured physical as well as thermo-mechanical properties of the synthetic composites, it is recommended to be applied as refractory materials in lining of permanent layer of iron and steel ladles and the brick network in the heat exchangers of glass furnaces.