Carbon dioxide emission reduction and utilization device and method for dredge ship

The invention discloses a carbon dioxide emission reduction and utilization device and a method for a dredge ship. The device and the method are used for capturing CO2 in waste gas of the dredge ship and applying carbon capture products to curing treatment of dredged sludge. The device comprises a CO2 absorption tower, a circulating pool, a solid-liquid separator and a pipeline mixer. Ship waste gas enters the CO2 absorption tower and is sprayed and absorbed by a mixed absorbent composed of an amino acid salt solution and a magnesium oxide slurry to form magnesium carbonate solid, magnesium carbonate and an amino acid salt solution are separated through the solid-liquid separator, and amino acid salt flows back to the circulating pool to be recycled. Magnesium carbonate and dredged sludge are uniformly mixed in the pipeline mixer and then discharged to underwater filling. By means of the technology, greenhouse gas emission reduction and dredged sludge solidification of the dredge ship are achieved at a time.