| 摘要 |
PURPOSE:To obtain clinker improved in residual expansion during heating cycle when made into spinel brick by blending calcined alumina having specific particles with magnesium hydroxide having specific particles in a wet state to give a mixed case or filtration case followed by burning. CONSTITUTION:Calcined alumina containing <=10wt.% particles of >=15mum is blended in a wet state with magnesium hydroxide containing <=0.3wt.% particles of >=15mum to give a mixed case and/or filtration case, which is burnt at >=1,700 deg.C to give the objective clinker. The clinker is slaking-resistant spinel.periclase-based clinker comprising 39-59wt.% MgO, 39-59wt.% Al2O3, >=98wt.% total amount of MgO and Al2O3, CaO and SiO2 in a molar ratio of CaO/SiO2 of >2.0 and has <=4.0% apparent porosity wherein spinel crystal and periclase crystal coexist and are uniformly distributed. The weight increase ratio after treatment in steam under 5 atmospheric pressure for 3 hours is <=1.0%. |
