The density of tin ore is larger than the paragenetic mineral, so the mining process of tin ore apply gravity separation. However, all kinds of Iron oxides exist in those ore, like magnetite, hematite, etc., which cannot be well separated by using gravity or flotation separation. Herein, magnetic separation and flotation separation will be used.
Crushing and Screening
Crush the raw ore to 20mm, then screen it to two grade, (20mm~4mm) and (4mm~0mm).
Put the 20~4mm ore into heavy medium cyclone to be selected. Then the ore will enter into the rod mill. After that, it will be preselected in jig. The tailings over 2mm will be abandoned, the 2mm ore will be put into shaking table.
The concentration from jig and shaking board will be separately selected by bulk flotation. The tailings will enter the shaking board to get qualified tin concentrates.
After the bulk flotation, the concentrate will be fine grinded, then will be do the flotation separation of lead zinc ore. After that Lead antimony concentrates and zinc concentrates will be produced.
The pulp enter into Φ300mm hydrocyclone, then overflow to Φ125mm and Φ75mm hydrocyclone group to remove the fine mud. The sand setting will enter into the process of thickening, desulphurization by flotation, and then cassiterite flotation.
For a certain tin ore dressing plant, Xinhai has taken flotation-gravity process by smashing raw ore to 200mm, and a close-circuit grinding by grinding it to 200mm occupied 60~ 65% . Process of “one roughing- two scavenging-one cleaning” has been applied to the flotation to grind copper and sulfur separately to 0.074mm occupied 95%. It also can get copper concentrate and sulfur concentrate through one roughing- two scavenging-one cleaning. Thereafter, using mixed flotation method can access to the aim of doing gravity process after tailings in sulfide and passing to one or two separation by shaking table, and one complex wash. It gets tin ore after slime flotation and finally tin concentrate by desulphurizing.