This book applies the selective precipitating and separating technology firstly to pyrometallurgical processes to change the composition, morphology and other properties of metallurgical molten slag. In order to meet the requirements of beneficiation processing the artificial ore (slag), that are modified by selective precipitating and separating technology.  Then, a series of beneficiation processes such as crushing, grinding, dissociation and classification are carried out on the modified slag, ultimately achieving the separating valuable elements from metallurgical slag and recycling.  It is the world's first patented technology, which can realize the resource utilization of metallurgical slag.