Extraction of Energetics from Sand Using Acetone: Acetone Extraction of DNT fromPacked Beds and Stirred Slurries of Sand; Recovery of Acetone for Reuse

摘要

A number of military industrial sites for production of energetic compounds(explosives, propellants, and pyrotechnics) have contaminated soils and lagoon sediments. Several methods exist for clean-up of these contaminated soils. The method of solvent extraction is expected to be competitive with the other methods provided that the acetone solvent can be recovered and reused in the process. The amount of solvent required for the separation impacts upon the operation of the extraction processes. The processes generally fall within two extremes: concentrated particle systems (such as in packed beds) or dilute particle systems (such as occur in slurries in stirred tank systems). This report contains the results of experiments conducted on packed bed and stirred tank acetone extraction of sand spiked with 2,4 Di Nitro Toluene (2,4 DNT). The overall economics of the acetone extraction process depends to a large extent on the recovery of the acetone for reuse. The results of this work show that acetone is effective in recovering energetics from sand either in packed beds or stirred tanks. The stirred tank extractor appears to be better than the packed bed extractor requiring less acetone per ton of soil and requiring a shorter contact time. The method that is most promising for recovery of the acetone is that of flashing with a cheap absorbent material such as wood chips to absorb the energetics. The overall cost analysis shows a savings of about $1.2 million per 50 thousand tons of soil washed. This work needs to be extended to clayey type soils and tests conducted on actual lagoon soils.