Cyanide Removal from Coke Making and Blast Furnace Waste Waters

摘要

The report gives results of a study to determine the feasibility of removing cyanide from coke making and blast furnace waste waters by ion flotation or column precipitate flotation of iron ferrocyanides. Ion flotation was reasonably effective on ferricyanide, but not on cyanide or ferrocyanide; therefore, efforts were concentrated on the formation and flotation of iron ferrocyanide precipitates. Test results also showed that precipitate flotation can be used as a primary process to remove most of the cyanide and could be used to meet effluent limitations under certain conditions, depending on feed concentration and volume. Ion exchange tests on synthetic solutions produced effluents which met discharge standards. This may be one possible secondary method of treatment; however, no work was done on flotation effluents or plant liquors.