Roasting

{
  "id": "MLC-T-ENV-024454",
  "term": "Roasting",
  "field": "Environment",
  "definition": "1. Heating (oxidizing) process where ground chromite ore is mixed with alkaline material (such as soda ash, sodium bicarbonate, and sodium hydroxide) and fed to a rotary kiln where it is heated to about 2,000 F, converting the majority of the chromium in the ore from trivalent to hexavalent chromium.\n\n2. The oxidation of ore or concentrate (usually of sulfide concentrates) at an elevated temperature to obtain metal oxides. The material is not melted. Roasting is usually used to change metallic compounds into forms more easily treated by subsequent processing.",
  "references": [
    "40 CFR 63.11412 (CFR 2013)",
    "EPA Abandoned Mite Site Characterization and Cleanup Handbook; Appendix A: Acronym List and Glossary of Mining Terms at http://www.epa.gov/superfund/policy/remedy/pdfs/appendix.pdf"
  ],
  "url": "https://mlchart.com/terminology/environment/roasting/"
}