Mud and sand quality-based utilization method

The invention discloses a mud and sand quality-based utilization method which comprises the following steps: S1, washing and screening mud and sand dug out from the seabed to respectively screen out sea sand, mud and coarse particles containing shells, S2, carrying out oxidation dechlorination and washing on the sea sand obtained in the step S1, and then dehydrating to obtain a sea sand product, and S3, carrying out quality-based utilization on the mud and sand obtained in the step S1. The method comprises the following steps: S1, conveying alkaline biochar into a sedimentation tank, synchronously conveying the slurry obtained in the step S1 into the sedimentation tank, neutralizing the slurry and the biochar to be acidic, and then carrying out filter pressing dehydration to obtain solid-phase neutral mud, and S4, uniformly mixing the neutral mud obtained in the step S3 with coarse particles obtained in the step S1 to obtain a planting soil product. According to the method, the seabed mud and sand are subject