PRODUCTION OF HIGH-STRENGTH GRANULAR GLOBULAR SLAG AS ARTIFICIAL AGGREGATE FOR CONCRETE AND APPARATUS THEREFOR

摘要

PURPOSE:To make it possible to produce high-strength granular globular slag close to natural gravel and having high quality as an artificial aggregate for concrete from molten slag having =1 basicity. CONSTITUTION:Molten slag 6 having =1 basicity is fed into a rotary drum type granulating machine 7 while dispersing the slag 6 through an oscillating trough. The molten slag 6 is granulated in an outer shell-producing zone 7A in which a cylindrical iron skin is cooled and outer shell is formed on the surface. The size of the slag is made uniform in a heat-reserved particle size- regulating zone 7B and molten state in the outer shell is kept. The temperature of the molten slag particles 8 is lowered in a state deposited in a conditioning furnace 9 and the slag particles 8 are tempered at 700-900 deg. in a cooling and crystallization zone 9A. The structure of the tempered slag particles is crystallized. The slag particles are annealed in a cooling zone 9B to obtain the objective high-strength granular globular slag 10 used as an artificial aggregate for concrete having high hardness and strength and having hardly any corner.