Dredged object excavation process and system

The invention discloses a dredged object excavation process and system, and belongs to the technical field of dredging construction, the dredged object excavation system comprises a ship body and an overflow drainage mechanism, the ship body is provided with a storage bin, the overflow drainage mechanism is arranged in the storage bin, and the overflow drainage mechanism comprises a fixed seat, a fixed cylinder, an overflow cylinder, a lifting assembly and a reinforcing assembly; the fixed seat comprises a fixed platform and a plurality of guide rods; the lifting assembly comprises a vertically-arranged lifting hydraulic cylinder, and a mounting frame is fixedly mounted in the overflow barrel. The reinforcing assembly comprises reinforcing sleeves, abutting rods and driving parts, the reinforcing sleeves and the abutting rods are in one-to-one correspondence with the guide rods, the guide rods penetrate through the reinforcing sleeves correspondingly, and the abutting rods penetrate through the reinforcing sl