Contaminated soil (CS) and biomass waste are potential resources. Their secure, scale, resource, and high-value utilization will bring significant socio-economic benefits. In present work, the basic properties, crystalline phases, microstructure and leaching behavior of porous ceramisite (PC) via CS and biomass waste were investigated systematically. The link of pore structure characteristics with leaching behavior of Cu and Cr was revealed. The environmental and economic benefits were also assessed. The results showed that the addition of 5∼15% pore-forming agent (carbon powder or biomass waste) made the matrix looser and the leaching amounts of heavy metals increased. However, the heavy metals leaching amounts was still lower than the critical limits of nonhazardous materials with immobilization rates higher than 97.5%. The leaching mechanism of Cu in the PC was controlled by initial wash-off, diffusion and depletion. The time period of the depletion dominated leaching is prolonged with increasing porosity. The leaching mechanism of Cr in the PC was mainly initial wash-off and depletion. The wash-off dominated the total heavy metal leaching amount, accounted for more than 80% of the total leaching amount. The leaching of Cu and Cr showed a positive correlation with (effective) pore volume of pores large than 1 μm, while demonstrating a negative correlation with the fractal dimension. The economic benefits of PC throughout the production process were analyzed, which showed that the production of PC using CS and biomass waste could eliminate raw material costs and could be subsidized by the government. This study provides an idea for the 100% utilization of CS and biomass waste as well as theoretical support for the disposal of solid waste.
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