Supercritical Carbon Dioxide Regeneration of Activated Carbon Loaded with Contaminants from Rocky Mountain Arsenal Well Water

摘要

The method of supercritical carbon dioxide (SCF CO2) regeneration of granular activated carbon (GAC) loaded with DIMP (diisopropyl methylphosphonate) from Rocky Mountain Arsenal Well (NO. 23-120) water was investigated. A laboratory-based adsorption/regeneration study was done in two parts. Part one compared the performance of three commercially available granular activated carbons as adsorbents for DIMP using SCF CO2 regeneration. Part two compared the effectiveness of SCF CO2 regeneration versus conventional thermal regeneration for one commercial GAC loaded with DIMP from RMA Well No 23-120. Economic evaluations based on the test data for the SCF CO2 regeneration system and for a conventional thermal regeneration system were made. Results indicated that thermal regeneration outperformed the supercritical process in restoring carbon capacity for DIMP. Results of the economic evaluation also indicated that the cost of the carbon regeneration step in the treatment of 600 GPM of RMA groundwater is $0.56 per 1000 gallons of water for the thermal process and $1.41 per 1000 gallons of water for the supercritical process. (Author)