Combined type biological rotating disk treatment device and method using same to treat sewage

The invention discloses a combined type biological rotating disk treatment device which is composed of a water inlet tank, a biological rotating disk reactor, a biological drop filter tank and the like. The invention further discloses a method using the combined type biological rotating disk treatment device to treat sewage. Sewage firstly enters the water inlet tank, is pumped by a jet pump and enters all section of a biological rotating disk through a plurality of pipelines. After the sewage is nitrified and denitrified by the biological rotating disk, the sewage falls into the biological drip filter tank through a water distribution plate. After being filtered, one part of the sewage is drained, and one part of the sewage flows back to the water inlet tank. A casing is covered on the biological rotating disk reactor, the jet pump can supply oxygen fro the biological rotating disk reactor, and air in the tank is filtered by the biological drop filter tank to be drained. A dissolved oxygen and liquid level control device are arranged in the tank. The jet pump is controlled to be opened according to dissolved oxygen and water inlet liquid level. Thus, low-energy-consumption running is achieved.