Patent ID: 9221696
Filing Date: 2015-12-29
Classification: C02F

Abstract:
1. A process for the treatment of a wastewater stream in electrochemical apparatus, said electrochemical apparatus comprising of at least one electrochemical cell containing suitable electrodes, to produce water with low concentrations of particular solutes, said process comprising: a) providing a feedwater stream which is a wastewater containing solutes therein, said solutes comprising any or all of the following: i) organic species or molecules; ii) ammoniacal nitrogen; iii) organic nitrogen; iv) inorganic sulfides; v) organic sulfides; vi) compounds containing the CN group; b) passing the feedwater from step a) through said electrochemical cell such that the water contacts the electrodes contained therein; c) causing a direct electrical current to flow through the electrochemical cell so as to destroy the undesirable solutes thereby producing a product water stream with a lower concentration of the undesirable solutes, said direct current to be varied and controlled to apply a specific power scheme to the electrochemical cell which includes at least one period of operation with a constant potential difference across the cell immediately followed by a period of operation with a constant current flowing through the cell; d) either returning the waste water passed through at least one of the electrochemical cells to the inlet of the electrochemical cell, or forwarding the partially treated waste water to the inlet of a subsequent electrochemical cell to which power is applied in accordance with step c) above, so as to effect a continuing treatment of the water to successively destroy the undesirable solutes present in said water; or jointly use of the above two methods.