The invention provides a
system for treating
sewage and producing biological oil by using microalgae. A
first light source device and a second
light source device of the
system are respectively arranged in a photo-
biological reactor and an oil accumulating tank; a CO2
gas supply device is respectively connected with the photo-
biological reactor and the oil accumulating tank through air passages; a
sewage sedimentation tank is connected with the oil accumulating tank through a pipeline and connected with the photo-
biological reactor via a pipeline through a microalgal liquid
mixing tank; the photo-biological reactor is respectively connected with the microalgal liquid
mixing tank and the oil accumulating tank via pipelines through a first microalgal liquid separating device; and the oil accumulating tank is connected with a second separating device through a pipeline. The invention further provides a method for using the
system to treat
sewage and produce biological oil. Through the use of the invention, the production of biological energy sources and other byproducts (such as
protein, cosmetic raw materials,
animal feed and the like) is realized while sewage is treated, so that the production cost is lowered, and the comprehensive utilization of waste resources and the energy-saving and emission-reducing
green production are achieved. The invention is suitable for cultivating microalgae from a laboratory to a factory, is skillful and unique in design, and is applicable to large-scale promotion and application.