The spiral separating is using gravity and centrifuge force to separate the minerals based on the different density of each mineral. You can see the video to get a clear understanding of how it works.
Spiral separator get two outstanding advantages: low price with high capacity;  and do not need power. The 5LL-1200 model could process upto 6 tons ores per hour, the price is only about 1350USD; while the operating cost is also very low, it's do not need power.
The spiral separator also get it's disadvantage, which is low concentration ratio and low recovery rate, so this kind of machine normally used in low value and massive processing quantity situation, such as black sand concentrating, hematite concentration, coal washing plant, and etc. And also it's could be used in primary processing, such as high capacity columibte processing plant, gold tailing reprocessing plant and etc.
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