System and method for treating oily wastewater and application of system and method

The invention discloses a system and a method for treating oily wastewater and application of the system and the method. The system comprises a separating device, a bag type filtering device and an organic metal film filtering device, the separating device is provided with an oily wastewater inlet, an oil phase outlet, a water phase outlet and a solid residue outlet, the bag type filtering device is provided with a water phase inlet and a filtered water phase outlet, and the organic metal film filtering device is provided with a filtered water phase inlet and a water outlet; a water phase outlet of the separating device is connected with a water phase inlet of the bag type filtering device, and a filtered water phase outlet of the bag type filtering device is connected with a filtered water phase inlet of the organic metal film filtering device. According to the system and method for treating the oily wastewater, the treatment process can be greatly shortened, the content of petroleum substances and suspended