NOVELTY - Alternate two-stage aerobic membrane bioreactor comprises a first reactor, a second reactor, an adjusting pond, flow rate meters, valves, centrifugal pumps, an automatic control gearbox, a water tank, a base liquid tank, an acid liquid tank, a first blower, a second blower, a pierced tube aerating device and a shallow aerating device. The first electromagnetic valve and a first flow rate meter are connected to the water outlet of the adjusting pond. The adjusting pond is connected with the first reactor by a water inlet pipe and a second electromagnetic valve.    USE - Used as an alternate two-stage aerobic membrane bioreactor.    ADVANTAGE - The alternate two-stage aerobic membrane bioreactor enables the high-concentration organic waste water after hydrolysis and acidification to be directly introduced into the aerobic membrane bioreactor for treating and discharging with good quality without methane producing reactions, and during the process: the discharge of the water is continuous, membrane pollution is reduced, membrane flux is restored to a highest grade, automatic control is realized, and is safe, stable and highly efficient.    DETAILED DESCRIPTION - Alternate two-stage aerobic membrane bioreactor comprises a first reactor, a second reactor, an adjusting pond, flow rate meters, valves, centrifugal pumps, an automatic control gearbox, a water tank, a base liquid tank, an acid liquid tank, a first blower, a second blower, a pierced tube aerating device and a shallow aerating device. The first electromagnetic valve and a first flow rate meter are connected to the water outlet of the adjusting pond. The adjusting pond is connected with the first reactor by a water inlet pipe and a second electromagnetic valve and a first chemical oxygen demand one-line meter are connected between the first flow rate meter and the first reactor. The adjusting pond is connected with the second reactor by a water inlet pipe. An electromagnetic valve and a chemical oxygen demand one-line meter are connected to the water inlet pipe, and a third electromagnetic valve and a second chemical oxygen demand one-line meter are connected between the first flow rate meter and the second reactor. A third chemical oxygen demand one-line meter is connected to the water outlet of the first reactor. A branch pipe of the water outlet pipe of the first reactor is connected to the second reactor. The outlet water of the first reactor is introduced into the second reactor, and a fourth electromagnetic valve and a first centrifugal pump are connected to the branch pipe. A fourth chemical oxygen demand one-line meter is connected to the water outlet of the second reactor. A branch pipe of the water outlet pipe of the second reactor is connected to the first reactor. The outlet water of the second reactor is introduced into the first reactor, and a fifth electromagnetic valve and a second centrifugal pump are connected to the branch pipe. Another branch pipe of the water outlet pipe of the first reactor is connected with the water tank. A second flow rate meter is arranged in front of the water tank and a fourth centrifugal pump and a seventh electromagnetic valve are connected to the branch pipe and another branch pipe of the second reactor is connected with the water tank. A third centrifugal pump and a sixth electromagnetic valve are connected to the branch pipe. A sodium chlorate liquid tank and a sulfuric acid liquid tank are arranged abreast with the water tank and a tenth electromagnetic valve together with a fourth flow rate meter, an eleventh electromagnetic valve together with a fifth flow rate meter, and a twelfth electromagnetic valve together with a sixth flow rate meter are respectively connected to the water outlets of the water tank, the base liquid tank and the acid liquid tank. The water outlet pipes of the water tank, the base liquid tank and the acid liquid tank are adjoined and connected to a fifth centrifugal pump and promoted by the fifth centrifugal pump and respectively connected to the first and second reactors by two back-flush pipes. A thirteenth electromagnetic valve is arranged on the back-flush pipe connected to the first reactor. A fourteenth electromagnetic valve is arranged on the back-flush pipe connected to the second reactor, and the liquid conveyed in the back-flush pipes is directly introduced into the reactors, where both the first and second reactors are provided with a membrane blowing and dissolved oxygen supply aerating system.