Abstract
Stringent environmental legislation and the desire to become zero discharge have motivated mining operations to treat and recycle process water. Cyanidation tailings effluent contains elevated concentrations of cyanide and thiocyanate (SCN−), precluding recycling to the BIOX® process without prior treatment to reduce SCN− to below 1mg/l. The current study investigated the effect of SCN− on individual microbial species. Iron oxidation by Leptospirillum ferriphilum was not affected by SCN− concentrations below 0.5mg/l, with concentration dependent inhibition observed between 0.75 and 1.25mg/l and complete inhibition of iron oxidation above 1.25mg/l. Sulphur oxidation by Acidithiobacillus caldus showed a similar trend, with limited inhibition below 1.25mg/l and almost complete inhibition above 1.25mg/l. Repeated sub-culturing at low concentrations induced adaptation, with adapted cultures currently growing at SCN− concentrations of 7mg/l. The phenomenon of inhibition at low concentration, with subsequent adaptation was repeated in stirred tank reactors, leaching a pyrite/arsenopyrite concentrate.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
