高铝质电炉盖预制块的研制与应用

Preparation and application of bauxite-based prefabricated block for electric furnace roof

针对耐火砖砌电炉盖耐用性差的实际情况，设计制造的预制块极便于组装砌筑整体电炉盖。研究了颗粒粒度组成、形状、结合剂、添加剂、减水剂等工艺因素对电炉盖预制块性能的影响，优化后的配料组成为：8～5mm为10％，5～3mm为20％，3～1mm为20％和1～0mm为20％、细粉总量30％，结合系统以5％CA80水泥、3％～5％的氧化铝微粉或者3％的结合助剂、0．2％的三聚磷酸钠与六偏磷酸钠混合减水剂为宜。据此生产的高铝质电炉盖预制块经过多家钢厂使用，取得了非常好的应用效果，在某厂电炉盖上使用寿命超过600炉。

In light of actual conditions of undesirable performance of the refractory blocks previously used for EAF roof, a kind of prefabricated monolithic refractory block which is easy to be assembled and fixed up for the block-type EAF roof has been designed and manufactured.. The effects of such a few processing factors as the grain sizes and shapes of the particles as well as the binder, additive and dehydrating agent on the performance of the prefabricated block for EAF roof have been investigated. The optimized aggregate composition of the bauxite based prefabricated refractory block used in the electric furnace roof involve grain size in 8～5 mm 10%： 5 ～3 mm 20%： 3 ～1 mm 20% and1～0mm 20% and the refined powder takes up 30% of the total. The ingredients of the binding materials are composed of 5 % CA80 cement, 3 % silica micro-powder or 3 %～5 % ultra-fine alumina powders, and 0.2 % trimeric sodium phosphate and hexamet sodium phosphate. The bauxite based prefabricated blocks for EAF roof produced in this way have been used in a number of steel-making works and very satisfactory resuits have been achieved. It＇s reported that in a specific steel-making works the campaign life of the EAF roof made of this block exceeds 600 heats.