Apparatus for purifying wastewater

The present invention provides an apparatus for purifying wastewater comprising a) a reaction tank which wastewater is introduced to and stays for a predetermined time; b) a circulation treatment apparatus comprising i) an electrolysis and electrocoagulation apparatus that is connected to wastewater inlet of the reaction tank, which wastewater is continuously introduced to, electrolyzed and electocoagulated; and ii) a mass transfer accelerator that dissolves gases self-produced in the electrolysis and electrocoagulation apparatus in treated water discharged from the electrolysis and electrocoagulation apparatus; and c) a sedimentation tank where treated water that overflows from the reaction tank stands, from which the resultant precipitates are removed.