:Spent refractories can be used for high-value applications, e.g., as refractory raw materials, if the corroded parts are sufficiently removed. Electrical pulse disintegration can cause a preferential fracture at the heterophase boundary in a pulverized object. This study applied electrical pulse disintegration to the treatment of spent refractories. The pulverizing experiment on MgO-based refractories corroded with slag by electrical pulse disintegration generated many free particles of undamaged and corroded parts. Calculation of the electric field intensity distribution following the application of an external electric field to the composite dielectric of undamaged and corroded parts showed that the electric field was concentrated around the interface. This means that local dielectric breakdown easily occurs around the interface. Moreover, it was estimated that particle fracture depends on its direction with respect to the electric field, and the influence of voltage is small.

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Iron compounds contained in typical Al2O3-SiO2 refractories were investigated by cross-section observation, micro spot composition analysis and micro spot X-ray diffraction. The morphology of iron compounds could be classified adjacent with pores system （type-A） and included in the aggregates system （type-B）. And the point of iron compounds in type-A was an aggregate composed of many particles. Fe2O3 and/or TiO2 were dispersed in the aggregate in type-B. The particles of iron compounds in type-A were identified as hematite. However, in the 1400 ℃（0.5h）-fired sample, the particles were identified as rutile and mullite. The Fe-components might have diffused after high temperature heat treatment.

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