Abstract: A system of sludge dewatering is described. The system comprises of a filter press, a sludge fee pipe, and acid feed pipe, and exhaust pipe and a discharge pipe. The sludge feed pipe is configured on the filter press. The acid feed pipe is connected with the sludge feed pipe. The exhaust pipe is connected with the sludge feed pipe. The discharge pipe is configured on the filter press. The system of the present invention can lead the acid solution into the filter press by the acid feed pipe so as to use in situ way to proceed filter cloth washing of the filter press.

Abstract: A power and signal common transmission device comprises a power adapter, a wire case, a transmission cable and a switching regulator. The power adapter serves for transforming DC power into AC power. The wire case serves for transforming the power wire from the power adapter into output pins. The cable is connected from the wire case to the switching regulator. The switching regulator serves for dividing power and signal transmission path and decreasing a voltage of the input power. Therefore, the system is more stable and has a lower decay so that it can be used in a longer cable.