A
straw indirect
carbonization-based soil improvement method and
system, the method comprising the following steps: (A) collecting
straw,
cutting the
straw into straw particles; (B) extruding and destroying the surface of the straw particles; (C) using
microwave heating to extrude the straw particles, obtaining puffed straw particles; (D) carbonizing the surface of the puffed straw particles, obtaining carbonized particles for
discharge into soil. The indirect
carbonization method of first breaking the wall and then puffing and carbonizing the surface can significantly reduce the energy consumed during
carbonization and shorten the
processing time of the straw, which is conducive to the straw carbonization and field application treatment of a large area of soil. At the same time, the surface-carbonized carbonized particles can provide sufficient
biomass carbon for the soil, and it is not necessary to remove part of the carbonized particles from the field due to the excessive
biomass carbon of the soil. In addition, the carbonized particles also well retain the nutrients in the straw.