NOVELTY - Pre-processed activated sludge-based short chain fatty acid production device comprises a gamma -ray irradiation device, and an ultrasonic crushing device comprising an ultrasonic generator processor, an ultrasonic detector and ultrasonic controllers. The ultrasonic generator processor is provided with a pot-shaped container. The ultrasonic generator processor comprises a tank container which is disposed in the ultrasonic generator processor. A discharge feeding port of the tank container is to the gamma -ray irradiation device. The ultrasonic detector is equipped with an ultrasonic probe.    USE - Used as pre-processed activated sludge-based short chain fatty acid production device.    ADVANTAGE - The device can increase the protein sludge, polysaccharides and other organic matter dissolved in the water level, and thus it increases the production of water-soluble organic matrix utilized in fermentation of acid sludge; increases the rate of acid sludge production; and shortens the anaerobic fermentation period.    DETAILED DESCRIPTION - Pre-processed activated sludge-based short chain fatty acid production device comprises a gamma -ray irradiation device, and an ultrasonic crushing device comprising an ultrasonic generator processor, an ultrasonic detector and ultrasonic controllers. The ultrasonic generator processor is provided with a pot-shaped container. The ultrasonic generator processor comprises a tank container which is disposed in the ultrasonic generator processor. A discharge feeding port of the tank container is to the gamma -ray irradiation device. The ultrasonic detector is equipped with an ultrasonic probe. The ultrasonic controller is respectively connected to the ultrasonic generator processor and electrically connected to the ultrasonic probe and a closed fermentation device. The closed fermentation device is connected to a closed fermentation tank. An inlet of the closed fermentation device of the ultrasonic generator processor is connected to a discharge port of the tank container. The top part of the closed fermentation device is provided with an exhaust valve and a pH adjusting agent addition port. The closed fermentation device is provided with a sealed pH detector.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation of the pre-processed activated sludge-based short chain fatty acid production device.