The invention discloses a comprehensive extraction method of ferro-silico-aluminum in
gangue, comprising the following steps of: using
gangue as a
raw material, crushing,
grinding, activating, carrying out acid leaching, filtering, neutralizing
free acid in the acid leaching filtered solution by the use of active
slag, filtering to obtain a neutralized acid leaching solution, adding a
sodium carbonate solution into the neutralized acid leaching solution, adjusting pH value, separating iron and
aluminium to obtain hydrous
iron oxide,
aluminium hydroxide and a by-product
sodium sulphate, adding
sodium sulphate and
coke into the acid leaching
slag which has undergone acid leaching and
filtration, carrying out a high-temperature melt reaction to recover
silicon so as to prepare
soluble glass, simultaneously recovering
sulfur dioxide to prepare
sulfuric acid, reusing
sulfuric acid for the acid leaching treatment, diluting the
soluble glass by the use of a
sodium carbonate solution, carrying out carborization to obtain white
carbon black, and reusing the carbonating solution for iron-
aluminium separation. The method provided by the invention has characteristics of wide application range of the
raw material gangue, high comprehensive
recovery rate, no output of by-products, less residue amount and the like, provides a novel technological process for high-efficiency
recovery of ferro-silico-aluminum from gangue, and expands the ways of gangue application.