Advanced Ramming Mix Based on Fused Zirconia Stabilized by Combined Additives of CaO and MgO for Lining of Carbon Black Production Reactor

摘要

Fused materials from ZrO2 stabilized by CaO or MgO, or the combined additive consisting of CaO and MgO are made.With using chemical, petrographic,X-ray phase and electron microscopic researches the main characteristics of these materials are determined.It is shown that, the materials of all compositions have low water absorption;they are characterized by equal structure.The materials stabilized by the combined additive consisting of CaO and MgO are presented by generally the cubic phase and a small amount of tetragonal and monoclinic ZrO2 phases.Depending on CaO:MgO ratio in the materials the tetragonal ZrO2 phase settles down in a cubic matrix as in the form of separate grains, and sites of net like structure in the form of a "woven" interlacing (2.9 ％ of CaO and 2.6 ％ of MgO).An influence of the above mentioned fused stabilized ZrO2 materials and quantity of monoclinic zirconia, on the forming of zirconia mix on a phosphate bond and properties of fired samples is studied.The samples from mix based on ZrO2 stabilized by the combined additive consisting of 2.9 ％ CaO and 2.6 ％ MgO with 20 ％ of monoclinic ZrO2 are characterized by the highest properties: after firing at 1580 ℃ open porosity of 14.3-14.8 ％,apparent density of 4.67-4.69 g/cm3, cold crushing strength of 62-68 Mpa, thermal shock resistance (1300 ℃-air) of 15 thermal cycles, linear growth of 0.2 ％.The manufacturing technology of powders mixture for ramming mix based on the new fused material from ZrO2 stabilized by the combined additive is developed and its production is mastered.From this mixture the large-size, shaped products on the phosphate bond are made at one of the carbon black production plant, which are installed in the combustion chamber of carbon black production reactor.