Optimization Research on the Solidification Residual Mud Technology of Magnesium Oxychloride Cement and Its Application in Green Buildings

With the acceleration of urbanization, the treatment of solid waste such as construction waste and river silt has become increasingly prominent. Traditional landfill or stacking methods not only occupy land resources, but may also cause environmental pollution. Magnesium oxychloride cement (MOC), as a low-carbon and environmentally friendly cementitious material, has become an innovative direction for the resource utilization and disposal of residual mud due to its fast hardening, high strength, and strong solid waste compatibility. However, MOC has problems such as frosting, halogen reflux, poor water resistance, and heavy metal leaching during the solidification of residual mud. This study optimized the performance of MOC by adding an appropriate amount of metakaolin and crystal waste residue, significantly improving its frost resistance, water resistance, and heavy metal fixation ability. The experimental results indicate that the comprehensive performance of MOC is optimal when the content of kaolin is 10%. In addition, the production energy consumption and CO ₂ emissions of MOC are much lower than those of traditional Portland cement, which has significant environmental and economic benefits. This study provides theoretical and technical support for the application of MOC in the fields of green building and ecological restoration.