Refractory Materials for Lead-Zinc Closed-Cycle Blast Furnace
Lead-zinc closed-cycle blast furnace is a type of European-style cupola furnace, which is mainly used for smelting pig iron, cast iron or lead-zinc furnace. It is mainly used for smelting of batch ferrous and non-ferrous alloy materials, such as cast iron, cast steel and non-ferrous alloys. It has the advantages of low labor intensity and environment protection, and it is the main furnace for smelting castings in Europe and American countries.
The lead-zinc closed-cycle blast furnace is usually equipped with a long muffle to form a closed cycle. It needs to be filled with refractory materials before it can be used. Different kinds of refractory materials have different performance, so the selection of them requires comprehensive consideration, integrating the properties of different materials and the working conditions of the furnace.
In general, the muffle of a lead-zinc closed-cycle blast furnace can be divided into combustible zone, drying zone and warming zone. The combustible zone needs high temperature resistant and slag resistant materials, so the brick of alkaline magnesia and magnesia-chrome brick are the preferred materials. In the drying zone of the muffle, the temperature change is relatively small and it is mainly used for insulation, so the bricks made of light fireclay and heavy fireclay are usually used. In the warming zone, the bricks made of high alumina or clay calcium can be used.
In addition, the refractory castable for lead-zinc closed-cycle blast furnace can also be used in some places where the conventional bricks cannot be used, such as chimney, furnace top, furnace wall, furnace bottom and furnace door. The refractory castables are generally made of high-alumina fire-resistant aggregates and cements. According to the characteristics of different refractory castables, it can be divided into calcium aluminate cement refractory castable, heavy calcium carbonate refractory castable, high alumina refractory castable and other refractory castables.
In order to ensure the efficient and environmentally friendly operation of lead-zinc closed-cycle blast furnace, the choice of refractory materials should be based on comprehensive considerations, such as performance requirements, furnace operation conditions, cost performance and other factors. At the same time, visual inspection, hardness and thermal shock resistance tests are essential for the refractory bricks and castables to ensure the quality and reliability of the materials.
