| 摘要 |
The phosphate mineral based reactive barrier prevents release of contaminant s from waste via reaction with contaminants at the interface between the barri er and the waste. The barrier is comprised of a phosphate mineral material that is primarily insoluble. The barrier is placed below, around, and/or on top o f contaminated materials such that they are completely contained by a grout curtain. The barrier can be a slurry, blended matrix with other inorganic agents, or composite with a geotextile or geofabric. These methods of construction are used singly or jointly. pH control may be used to optimize chemical reactions within the barrier. The mechanism relies on the phenomena of adsorption, surface precipitation and co-precipitation of metal phosphate surface precipitates to chemically retard diffusion from the waste. Immobilization may occur secondarily when a small percentage of the phosphat e minerals partially dissolve and the phosphate precipitates with metals to fo rm metal phosphate precipitates.
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