Outer circulating type pressurized dissolved air flotation-film separation water treatment device

The utility model discloses an outer circulating type pressurized dissolved air flotation-film separation water treatment device. The device comprises a coagulation system, an air flotation system and a film separation system, wherein the coagulation system, the air flotation system and the film separation system are sequentially connected; the air flotation system comprises an air floating pond, a dissolved air releaser, a slag scraper and a dissolved air tank, the air floating pond is separated by a flow guide baffle into a contact chamber and a separation chamber, the dissolved air releaser is arranged at the bottom of the contact chamber, the dissolved air releaser is connected with the dissolved air tank arranged outside the air floatation pond, and the slag scraper is arranged on the top of the separation chamber; the film separation system comprises a film separation pond and a film separation component, the film separation component is arranged in the film separation pond, a concentrated water outlet of the film separation pond is connected with the dissolved air tank of the air flotation system, and therefore the concentrated water after film separation is thrown into the dissolved air tank to form dissolved air. The device can effectively relieve film pollution and improve film flux and can be suitable for advanced treatment of waste water with the higher concentration.