Abstract: A mixing apparatus and system is described for controlling the mixture of a de-icing fluid and water. Water, supplied by a centrifugal pump, is monitored by a flow meter which sends a flow rate signal to a controller. Glycol is supplied by another centrifugal pump to a calibrated multi-port digitally controlled flow valve. The temperature of the glycol and the pressure differential across the flow control valve are monitored by sensors, and the controller controls the flow of glycol from the flow control valve to maintain the preset glycol concentration.