Apparatus for treating waste water having electrocoagulation part and sterilizing water suppling unit and method of treating waste water

摘要

PURPOSE: Provided are a wastewater treatment apparatus and a wastewater treatment method with two electrocoagulation tanks connected in series to repeatedly perform electrocoagulation, thereby increasing treatment efficiency, and a sterilizing water spraying system to spray sterilizing water upward in a rear side of electrocoagulation tank. CONSTITUTION: The apparatus comprises a first electrocoagulation unit(14) with a treatment tank(18) for treating raw wastewater, electrode plates(20) vertically installed in the treatment tank(18), and a power supply and control device(22) for applying DC power to the electrode plates(20) in such a way that two adjacent electrode plates(20) are the opposite; a second electrocoagulation unit(30) connected to the first electrocoagulation unit(14) in series and comprised of a treatment tank(32) for treating outflow of the first electrocoagulation tank(14), electrodes(20) vertically installed in the treatment tank(32), and a power supply and control device(22) for applying DC power to the electrode plates(20); and a sterilizing water supply unit for spraying sterilizing water to the treatment tank(32) of the second electrocoagulation unit(30). The method comprises the steps of introducing raw wastewater to a first electrocoagulation unit(14), feeding bentonite to the raw wastewater to be introduced to the first electrocoagulation unit(14), removing contaminants in wastewater by a first coagulation in the first electrocoagulation unit(14), further removing contaminants in the outflow of the first electrocoagulation unit(14) by a second coagulation on a second electrocoagulation unit(30), and spraying sterilizing water to the outflow of the first electrocoagulation unit(14) during the second coagulation.