Chemical technique for sequestering ammonia off-gassing from solidified

USH283H · kind H · statutory invention registration

Inventors

• Tommy E. Myers · Vicksburg, US
• Douglas W. Thompson · Amarillo, US

Key dates

• Grant date: Jun 2, 1987

Classification

• Technology area (CPC —): General

Abstract

A method for sequestering ammonia off-gassing by chemical treatment of certain hazardous wastes prior to solidification of such wastes, the invention involves mixing of magnesium sulfate heptahydrate and phosphoric acid with waste containing ammonia nitrogen to form ammonium magnesium phosphate hexahydrate complex and thus control the release of ammonia vapors during the solidification process and from the cured and solidified waste products of the solidification process. The present method results in the precipitation and complexation of ammonia nitrogen in the waste to effectively isolate the ammonia nitrogen in a substantially water insoluble complex which is incorporated into a solid product disposable within landfill sites after further treatment with solidification reagents in known solidification processes. The several embodiments of the present method are preferably employed to pretreat ammonia nitrogen containing waste prior to use of a solidification process, thereby significantly reducing the amount of ammonia gas released during solidification processing.