NOVELTY - A fermentation raw material pre-processing device for large biogas engineering, comprises a receiver (1), a stripping mixer (2), a circulating groove (3), a scum separator (5), a suspension cutter (6), a circulating mixer (7), a mixing and crushing machine (8), and a unit discharging machine (9); where the receiver (1) is set with a feeding opening (10), a circulating mixer joint (13), and a discharging opening (14); the discharging opening (14) and the stripping mixer (2) are connected; and the circulating mixer joint (13) and the circulating groove (3) are connected.    USE - The fermentation raw material pre-processing device is useful for large biogas engineering (claimed).    ADVANTAGE - The fermentation raw material pre-processing device can process multiple organic wastes and fermentable materials, comprising sludge in a sewage plant, at the same time. Moreover, the solid content of processed materials can be 8-15%. Additionally, the biogas generation rate of the anaerobic reactor can be improved by 10-15%.    DETAILED DESCRIPTION - A fermentation raw material pre-processing device for large biogas engineering, comprises a receiver (1), a stripping mixer (2), a circulating groove (3), a scum separator (5), a suspension cutter (6), a circulating mixer (7), a mixing and crushing machine (8), and a unit discharging machine (9); where the receiver (1) is set with a feeding opening (10), a circulating mixer joint (13), and a discharging opening (14); the discharging opening (14) and the stripping mixer (2) are connected; the circulating mixer joint (13) and the circulating groove (3) are connected; a stirrer component (16) is arranged in the stripping mixer (2); the stripping mixer (2) and the circulating groove (3) are connected; one end of the circulating groove (3) is connected with the stripping mixer (2); the other end is connected with the stripping mixer (2) through the receiver (1); it forms a fluid circulating channel; the circulation power is supplied by the circulating mixer (8); the desilting separator (4) is in the circulating groove (3); it comprises a cylinder (21); two ends of the cylinder are a discharging opening (24) and a feeding opening (25) respectively; the feeding opening (25) is in tapered center of the stripping mixer (2); the discharging opening (24) is higher than the top cover of the stripping mixer (2); the scum separator (5) is in the circulating groove (3); the desilting separator (4) and the circulating mixer (7) in the circulating groove (3) are separated by the scum separator (5); the suspension cutter (6) is between the scum separator (5) and the receiver (1); one end of the mixing and crushing machine (8) is connected with the stripping mixer (2) through a pipeline; the other end is connected with the inlet of the unit discharging machine (9); and the outlet of the discharging machine (9) is connected with the anaerobic reactor.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of the fermentation raw material pre-processing device for large biogas engineering.    Receiver (1)    Stripping mixer (2)    Circulating groove (3)    Scum separator (5)    Suspension cutter (6)    Circulating mixer (7)    Mixing and crushing machine (8)    Unit discharging machine (9)