The low flow of the thickener 1 is controlled by valves, flow meters, and concentration meters, and then enters the slurry pump 4, and then feeds the main pump 5 to send the slurry to the destination. Control the rotation speed of the slurry pump 4 according to the concentration. When the concentration is high, the pump rotation speed increases; The main pump 5 adjusts the rotating speed according to the inlet pressure. When the pressure is high, the rotating speed is increased, and when the pressure is low, the rotating speed is reduced. The advantage of this scheme is that the underflow flow of the thickener is controlled by the slurry pump, without valve control, avoiding valve wear, without mixing tank, avoiding power consumption, and reducing operating costs.

Scheme 2: Thickener 1 has low flow, pool 2 has low flow, controlled by valves, flowmeters, and concentration meters, enters stirring tank 3 for stirring, and laser level gauge monitors the liquid level. The bottom flow has valves, flowmeters, and concentration meters. Position, concentration, flow control the amount of water added, thickener bottom flow, adjust the slurry pump speed to control the pipeline flow, the slurry pump 4 feeds the main pump 5 for the bottom flow of the stirring tank 3, and the main pump discharges the slurry. The characteristics of this scheme It is called stirring tank 3, open control, the disadvantage is that the liquid level needs to be controlled, and the underflow flow of the thickener needs to be controlled by a valve, which is much  easy to being wearing out.