Tunnel counter-slope dewatering and purifying device and control method and purifying method thereof

The invention discloses a tunnel counter-slope dewatering and purifying device and a control method and a purifying method thereof. The tunnel counter-slope dewatering and purifying device comprises a tunnel water tank, the tunnel water tank is connected with the input end of a centrifugal extraction device used for separating silt, the output end of the centrifugal extraction device is connected with a water pump device and a sewage purifying device respectively by a pipeline, and the output end of the sewage purifying device is connected with the pipeline of a water reservoir; sewage in the tunnel water tank pass the centrifugal extraction device and is discharged to the sewage purifying device by a water pump, and the water is purified by the sewage purifying device and stored in the water reservoir; a monitoring module is arranged in the tunnel water tank and is connected with the controller, and the controller is provided with an alarm. When monitoring indicators in the tunnel water tank are higher than preset values, the alarm can send alarm signals. The tunnel counter-slope dewatering and purifying device is scientific and reasonable in design and has the advantages of low price, silt separation, capabilities of monitoring displacement in real time and purifying sewage, remote control and the like.