Research on Properties of Prefabricated Pellets of Silicothermic Process After Calcination in Flowing Argon Atmosphere

Abstract

In the Pidgeon process, the separation of calcination and reduction process leads to a long production cycle and high energy consumption. Based on the novel preparation method of pellets of silicothermic process, the low-grade magnesite with abundant resources in Liaoning Province was used as raw material, calcium source, reducing agent, and fluorite were added to pelletizer directly and then calcined and reduced in flowing argon atmosphere. The properties and micromorphology of prefabricated pellets after calcination were investigated in the work. The experimental results showed that the hydration activity and compressive strength of prefabricated pellets after calcination reached 23.0% and 998 N, respectively. The recovery ratio of magnesium metal was more than 80% in the reduction process. The research on calcination of prefabricated pellets in flowing gas provided a theoretical basis for continuous extraction of magnesium.