Persulfates for soil and groundwater remediation
ISGS® Technology
ISGS® remediation technology utilizes a permanganate-based solution to geochemically stabilize dense non-aqueous phase liquids (DNAPL) in the aquifer.
Permanganate and other proprietary reagents are selected based on the particular characteristics of each site and are mixed on-site to form an aqueous solution that can be injected into an aquifer either through existing wells or by direct pressure technology.
As the solution migrates through the treatment area, it oxidizes the contaminants, resulting in partial mass removal. The ISGS® technology also reacts with the contaminants in the treated area, coating the NAPL surfaces with stable mineral precipitates that reduce mass flow.
KEY BENEFITS
- Prevents contaminants from leaching into the environment
- Application and treatment can be done in situ
- Can be more cost-effective and efficient than conventional cement stabilization
EXAMPLE CONTAMINANTS
- PAHs
- Chlorinated solvents
- Chreosote
Key Functions
- Fixed well injections
- Direct push injections
TECHNOLOGY: IN SITU STABILIZATION
When released into the environment, chlorinated solvents, coal tar, creosote, and heavy crude oil are frequently present as DNAPL and represent a long term secondary source of contamination. Physical removal or in situ remediation of DNAPL is not always practicable due to the depth of contamination, aquifer geology, the presence of physical surface structures, or other factors making hydraulic containment (e.g., long-term pump-and-treat) or in situ stabilization the only viable remedial action. The process of in situ stabilization prevents or slows harmful chemicals from contaminated soil, sediment and sludge, from leaching into the environment. The contaminants are chemically immobilized under ground making them less likely to be released into the environment.
Technical Documentation
In situ geochemical stabilization (ISGS) involves the use of modified sodium permanganate (NaMnO4) developed for in situ treatment of non-aqueous phase liquids (NAPL). When ISGS reagents are added to a contaminated aquifer, they react with organic (and certain inorganic) constituents of interest (COI) present as soil residues (e.g., NAPL or ganglia). Various reactions associated with ISGS processes serve to physically crust NAPL and rapidly reduce aquifer permeability. This stabilizes NAPL remnants and accelerates remediation by naturally attenuating dissolved COI/components of the contaminant plume through source stabilization and flow reduction.
Evonik’s laboratory created the KLOZUR® field test kit to provide a quick and reliable measurement of persulfate in the field.
There are two different kits available, depending on the activation method used. Each kit is capable of running ten tests and has a measurement range of 1g/L to 100g/L, with a theoretical accuracy of ±1g/L and ±2g/L respectively.
