Acidity production and buffer requirements for in situ bioremediation of chlorinated solvents
Courtesy of True Blue Technologies, Inc.
Acidity production and buffer model
- Developed batch abiotic model in PHREEQC-2 using overall stoichiometry for reductive dechlorination
- Reaction is divided in steps, buffer is added as required to maintain minimum design pH
- Expected extent of dechlorination
- Site water chemistry
- H2 consumption by competing electron acceptors (sulphate and iron reduction)
- Site mineralogy (mineral precipitation and dissolution)
- Specific organic substrate and buffer added
- A gas phase can form if total partial pressure (CO2, H2O, H2, H2S, O2) exceeds a threshold value
- Use of acetate as electron donor
De-chlorination Application – Proctor and Gamble, NC., USA.
Hanovia Photon UV Systems. Installation Date 2001 System Configuration – Two Hanovia Photon PMD320G4 Dechlorination and Disinfection Systems, complete with Certified UVC Lamps, Validated UV Monitors, Lamp Power Switching, UV Dose Control, and optional Quartz Sleeve Automatic Wipers. Variable Flow: Up to 180 usgpm (40.9m3/hr) per stream Water Quality: Pre R.O. filtered city water. Background P & G Charlotte USA had previously dechlorinated their plant water using sodium metabisulfite. It was necessary...
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