Method for stabilization of heavy metals and odor control with dicalcium phosphate dihydrate powder

Abstract

This invention provides a method for stabilization and treatment of heavy metal bearing materials and wastes subject to acid leaching tests or leach conditions and odor limits by addition of acid semi-soluble DiCalcium Phosphate DiHydrate such that the leaching potential is inhibited to desired levels and odors are reduced to desired levels and the material or waste is free flowing, more permeable, less weight and permits immediate handling and disposal or reuse. The resultant material or waste after stabilization is deemed suitable for on-site reuse, off-site reuse or disposal as RCRA non-hazardous waste.

Description

Claims

1. A method of reducing the leachability and odor of heavy metal bearing material or waste, comprising contacting heavy metal bearing material or waste with DiCalcium Phosphate DiHydrate in an amount effective in reducing the leaching of heavy metals from the material or waste to a level no more than non-hazardous levels as determined in an EPA TCLP test, performed on the stabilized material or waste, as set forth in the Federal Register, vol. 55, no. 126, pp. 26985-26998 (Jun. 29, 1990), and odor in accordance with odor index by olfactory measure.

2. The method of claim 1, wherein DCPDH is in pulverized or in fine particle form.

3. The method of claim 1 wherein As, Ag, Ba, Cd, Cr, Pb, Se, Hg, Sb, Cu, Ni and Zn bearing material or waste is contacted with DCPDH in effective amount to reduce leaching to TCLP non-hazardous or desired levels and reduce odor to desired levels prior to collection of such material or waste in containers.

4. The method of claim 1 wherein As, Ag, Ba, Cd, Cr, Pb, Se, Hg, Sb, Cu, Ni and Zn bearing material or waste is contacted with DCPDH in effective amount to reduce leaching to TCLP non-hazardous or desired levels and reduce odor to desired levels during or after collection of such material or waste in containers or during or after generation of material or waste as a regulated waste.

5. The method of claim 1 wherein the material of waste includes incinerator ash, incinerator bottom ash, incinerator combined ash, incinerator flyash, incinerator scrubber residue, shredder waste, shredder fluff, wire shredder insulation, contaminated soils, foundry sand, steel mill flyash, slag, smelter ash, lead smelter ash, foundry flyash, lead projectiles, lead projectile berm material, lead paint residue.

6. The method of claim 1, wherein DCPDH is combined with cement kiln dust, Portland cement, silicates, lime, dolomitic lime, magnesium oxide, ferric chlorides, ferric sulfates, ferric ions, mineral complexing agents, and combinations thereof.

7. A method of reducing the leachability and odor of combined heavy metal bearing material or waste, comprising contacting heavy metal bearing material or waste with DCPDH in an amount effective in reducing the leaching of combined heavy metals from the material or waste to a level no more than non-hazardous or non-acceptable levels as determined in SPLP, MEP, United Kingdom DI, Japan DI or Swiss sequential water leach test, performed on the stabilized material or waste, and reducing odor to desired levels.

8. The method of claim 7 wherein As, Ag, Ba, Cd, Cr, Pb, Se, Hg, Sb, Cu, Ni, and Zn bearing incinerator ash, foundry dust, smelter ash, smelter slag, shredder fluff, wire insulation, steel mill ash, is contacted with DCPDH in effective amount to reduce leaching to non-hazardous or desired levels and odor to desired levels prior to collection of such waste or materials in containers.

9. The method of claim 7 wherein As, Ag, Ba, Cd, Cr, Pb, Se, Hg, Sb, Cu, Ni, and Zn bearing incinerator ash, foundry dust, smelter ash, smelter slag, steel mill ash, shredder fluff, wire insulation, is contacted with at least on stabilizing agent in effective amount to reduce leaching to non-hazardous or desired levels and odors to desired levels during or after collection of such waste or material in containers or during or after generation as a regulated waste.