Electrokinetic dewatering of phosphatic clay settling areas: numerical simulation and economic assessment

A mathematical model is presented for the electrokinetic dewatering of suspensions of phosphatic clays. The modeling approach couples a boundary-element model for solution of Laplace’s equation to a recently developed constitutive equation that relates the change in solids content with applied electric field and time. The observation that the electric field controls both the maximum solids content achievable and the time required to reach that value is shown to severely constrain the application of electrokinetic dewatering strategies to an entire clay settling area. The approach, however, may be feasible for implementation as part of a continuous plant process.