Method for preparing dredging sediment into soil remediation agent

The invention discloses a method for preparing dredging sediment into a soil remediation agent. The method comprises the following steps: 1, separately drying the dredging sediment and agricultural straws; 2, separately smashing the dried dredging sediment and the dried agricultural straws; 3, fully mixing the smashed dredging sediment and the smashed agricultural straws according to the the mass ratio of 1:(3 to 5) to obtain a mixture; 4, pyrolyzing the mixture at a high temperature in an oxygen deficient condition to obtain charcoal; 5, perform acid activation on the charcoal to obtain activated charcoal. The activated charcoal is the soil remediation agent which is suitable for remediating and improving soil.