| 摘要 |
A process for decontaminating soil containing a chlorinated cyclical organic compound contaminant is described, the contaminant selected from chlordane, dieldrin, toxaphene, aldrin, endrin, heptachlor, heptachlorepoxide, and alpha, beta, gamma and delta benzene hexachlorides. The soil must also contain populations of variable anaerobic and aerobic microbes capable of transforming the contaminant into harmless materials. The process comprises the steps of: (a) admixing the soil with amendment material in an amount of at least 10% and up to 95% by weight of the resultant mixture of the soil and amendment material, to form a solid compost mixture comprising organic nutrient for composting, (b) composting the soil while maintaining the temperature of the compost mixture in the range of 20°C to 65°C and the water content of the compost mixture in the range of 40% to 100% water holding capacity, (c) during the composting, maintaining a redox potential level of the compost mixture below about negative 200 mV until a significant amount of the contaminant is degraded, (d) oxygenating the compost mixture to raise the redox potential level of the compost mixture to above positive 100 mV, and maintaining the redox potential level to above positive 100mV until the contaminant is further degraded and (e) repeating the sequence of steps (a) to (d) until the contaminant is degraded to less than 140 ppm per ton of the soil. |
