PLC-control-based (programmable logic controller-control-based) rainwater recycling control system for red mud yard of aluminum oxide plant

The invention relates to a control system, in particular to a PLC-control-based (programmable logic controller-control-based) rainwater recycling control system for a red mud yard of an aluminum oxide plant. The PLC-control-based rainwater recycling control system improves working efficiency and is stable in operation. The PLC-control-based rainwater recycling control system comprises an upper computer and a water pump outlet valve connected with a water collecting tank. A PLC is disposed between the upper computer and the water pump outlet valve. An optic fiber transceiver connected by optic fibers is disposed between the upper computer and the PLC. Automatic control is used to guarantee that no alkaliferous wastewater is emitted to the outside of the yard to protect water quality and farmland soil around the yard from being polluted and water consumption and lye consumption in aluminum oxide production are saved, and accordingly the effects of low carbon, environmental protection and emission reduction are