Non-point source contaminant purification system and method thereof for an early stage rain water by multi-stage treatment

PURPOSE: A device and a method for clarifying the natural rain water through multi-step processing are provided to effectively clarify the pollutant including in initial rain through multi-step processing, thereby conveniently maintain and mange the rain by being improved the purified performance and lifetime. CONSTITUTION: A natural type initial superiority clarification device include a settling tank(1), a first filtering media screen(2), a purification unit(5). The purifying unit includes a vegetation unit by being formed between a first barrier and a second barrier. The first barrier provides a first space with a first filtering media and has an overflow hole and a classification inlet on the wall. The second barrier is separated from the first barrier and has an overflow vent and a plurality of zip flood control outlets. The purification unit includes a collecting water perforated drain pipe, a filtering media, a distribution perforated drain pipe, and a gravel layer, a vegetation layer. The collecting water perforated drain pipe has a mesh structure filled with a filtering media inside and has a rain passing hole in external side as a stainless material. The filtering media is installed in upper part of the collecting water perforated drain pipe. The distribution perforated drain pipe has a rain passing through hole in outer surface as a stainless material by installed in upper side of the filtering layer and has a filtering inside. The gravel layer comprises upper layer of a distribution perforated drain pipe. The vegetation layer is formed in upper side of the gravel layer. The purifying outflow hole capable of discharging the purified rain to the lower side of the waterproof floor is included on the waterproof floor located in lower side of the collecting water perforated drain pipe of the purified unit.