In accordance with some embodiments herein, an apparatus is provided. The apparatus includes a conduit, a first
electrode, a second
electrode, a power source, a valve, and a controller. The conduit is configured to conduct a mixture along a flow path. The first
electrode is placed proximal the flow path defined by the conduit. The second electrode is placed proximal the flow path defined by the conduit. The power source is configured to apply a
voltage across the first electrode and the second electrode. The valve is coupled to the conduit and configured to
control flow of the mixture through the flow path defined by the conduit. The controller is configured to determine a first
capacitance of a first
capacitor established by the first electrode, the second electrode, and the mixture flowing along the flow path. The controller controls the valve based upon the first
capacitance.