(9544)SULFURIZATION OF MERCURY FROM GOLD PRODUCTION USING A PLANETARY BALL MILL

摘要

Mercury is produced as a byproduct from gold mines and, historically, has been transferred to recyclers and used for various industrial processes and products. However, under the Minamata Convention on Mercury, adopted in 2013, the intentional use of mercury in processes or products will be minimized in the world. Surplus elemental mercury should be treated as a hazardous waste and consequently, should be converted to a more stable chemical form for long-term storage or permanent disposal. A stabilization method has been developed to react mercury and sulfur using a planetary ball mill. The planetary ball mill can produce high-energy conditions and enable samples to react within a short period of time. A series of tests has been conducted to confirm that mercury sulfide can be produced using a bench scale machine with 2400 mL pot. Under a suitable experimental condition with 25 mm ball diameter, 30% of ball filling rate and 1.05 of molar ratio of S/Hg, a powdered mercury sulfide product was successfully obtained in 60 minutes. The leachability and atmospheric emission from the product was extremely low. This stabilization method would contribute to an environmentally sound mercury management strategy for the gold industry.