Hydrocyclone is necessary equipment for mineral processing in dewatering, classifying and thickening. It plays different role but important role in these processes.For classifyingIn gravity processing plant, hydraulic cyclone as classifying equipment processes desliming and classifies fine particles. For example, a tin mineral beneficiation use hydrocyclone to classify feeding ore with high mud content (-10 mesh of 70-80%). In desilting, the sand -10 mesh is occupied 10%, and get the mud removal efficiency of more than 80%. Hydrocyclone also can recycle fine stone, which reduce the overflow grade. With these advantages, heavy physical labor becomes mechanization to improve working condition and bring good results in technology and economy.In flotation process of a lead-zinc ore grinding system, hydrocylone is used to control classification. The hydrocyclone ensures effective ore fineness and reduce middlings. It also can use the single tank to select Pb avoiding the over crushing, and improve the classification efficiency. Based on keeping the original lead and zinc recovery rate, hydrocyclone installation effectively improves the processing quantity 7.3%.In the tailings recovery, Xinhai used hydrocyclone to recover sulfur for pyrite tailings (sulfur content 24%). Without adding any equipment installation, this plant obtained the sulfur concentrate 30-35%, and the recovery rate reached 60%. In addition, the plant would also treat hydrocyclone as alternative classifier in strengthening dressing process, and finally this small improvement made the overflow -200 mesh accounted for 70%, increased to -200 mesh accounted for more than 80%, greatly improving the monomer separation degree.For dewateringXinhai is the first company came up with the dry tailings stacking concept, and creatively develop new process. This process includes Xinhai hydrocyclone, and improves the dewatering efficiency to 70%-80%.