RESEARCH ON ENVIRONMENT-FRIENDLY MgO-CaO-ZrO_2 REFRACTORIES AND ITS APPLICATION

摘要

Considering MgO-Cr_2O_3 refractories used in the alkaline environment led environmental problems caused by hexavalent chromium pollution, MgO-CaO-ZrO_2 refractories is a new type refractories for substitution of MgO-Cr_2O_3 refractories using in secondary refining vessels in metallurgical industries for its excellent properties as well as environment-friendly features. In the present work, Micro-ZrO_2 and Nano-ZrO_2 were used as additives applied in MgO-CaO refractories to respectively investigate their improvement on performance of MgO-CaO refractories. The results showed that the densification of the MgO-CaO refractories was appreciably promoted when a small amount of ZrO_2 was added, the thermal shock resistance and slaking resistance of the MgO-CaO refractories could be appreciably improved with a small amount of ZrO_2 addition. The effect of nano-sized ZrO_2 additive on densification, thermal shock resistance and slaking resistance was more obvious than micro-sized one. The penetration index of MgO-CaO refractories was significant reduced as the amount of nano-sized ZrO_2 additive increased.