An Assessment of South African Chromite Sand Crushing Ratio

Mechanical reclamation is the de facto method of sand recycling in most foundries used to limit sand dumping and adhere to environmental regulations. The latter metal casting imperatives align with the United Nations Sustainable Development Goals of Responsible Production (Goal 12 - Ensure sustainable consumption and production patterns.). The crushing ratio, which essentially assesses the propensity of the sand to produce fine particles during moulding operations, is a critical property to predict the effectiveness of the mechanical reclamation process. This study assesses the crushing ratio of South African chromite sand. Five samples from the top worldwide producers were evaluated and compared. Rod milling was used to simulate mechanical reclamation. After testing, it was found that this crushing ratio varies between 1.68 and 1.93 after 9 minutes. Good statistical linear correlations were established between the crushing ratio of samples with Cr/Fe ratio, chromite content, and grain size. The investigation contributes to additional knowledge of chromite sand for foundry applications.