Biogas slurry ecological purifying device

A biogas slurry ecological purifying device comprises an adjusting tank (1), a facultative tank (2), an aerobic tank (3), a fish-culturing tank (4) and a clarifying tank (5); each tank is provided with a liquid outlet pipe and a liquid inlet pipe, the liquid outlet pipe of a previous tank is communicated with the liquid inlet pipe of a next tank, a control valve (8) is arranged therebetween, outflow water of the clarifying tank (5) is respectively connected with a discharge pipe and a backflow pipe (7) by a three-way pipe (6) and a control valve thereof, the backflow pipe is communicated with the adjusting tank (1), the liquid outlet pipe of the adjusting tank is provided with a flowmeter (14), the backflow pipe (7) is provided with a circulating water pump (11), and the aerobic tank (3) is internally provided with an aerating apparatus (12) and filler. The device is used for biogas slurry purification, depends on nutrient absorption and interception of aquatic plants and photosynthesis of leaf surface to purify the biogas slurry, and adopts a biological purification and circulating treatment way depending on algae, plankton, microorganism, clams and fish to conduct comprehensive mutual synergy to realize that discharge water reaches the standard, thus having the advantages of being fast and high-efficient, and being concurrently engaged in multiple operation.