Integrated assessment for aerobic biodegradability of sulfide mineral flotation collectors

摘要

The biodegradability of flotation collectors has the most important impact on mine environment. Understanding the flotation collectors' biodegradability is a crucial element in developing an informed strategy for analysing and managing the mine environment. Integrated assessment method including three biodegradability tests namely, BOD_5/ COD_(Cr) ratio test, Static-flasks test and OECD 301B have been established to evaluate the aerobic biodegradability of the sulfide mineral flotation collectors. Consistent conclusions have been obtained through these three biodegradability tests: the aerobic biodegradation of the different sulfide mineral flotation collectors is different, namely, sodium diethyldi-thiocarbamate is a readily biodegradable collector, and ammonium butyl-dithiophosphate is partially biodegradable. However, n-butyl xanthate and ethylthionocarbamate are considered as poorly biodegradable. Besides, the order of aerobic biodegradability of these collectors is: sodium diethyldithiocarbamate ＞ ammonium butyl-dithiophosphate ＞ n-butyl xanthate ＞ ethylthionocarbamate.