... is one of the relative new methods for gravity concentration. As a rougher or cleaner device, it is ... upward flow, downward flow and action time produced by the sine-wave pulse curve, enhances the loose ... Zn: 2.04%, respectively; water consumption is reduced by 30%-40%, site area is decreased 1/3, ... the stroke can be adjusted, dragging by the electromagnetic adjustable speed motor makes the pumping ...