Method for reduction of heavy metal leaching from hazardous waste under acidic and nonacidic conditions

A non-hazardous solid waste mixture which may be safely disposed of in a landfill, comprising a solid hazardous waste containing unacceptable levels of leachable metals selected from the group consisting of lead and cadmium, mixed with at least one fist agent selected from the group consisting of magnesium oxide and magnesium hydroxide, and an additional agent which is triple superphosphate, in quantities sufficient so that under both acidic and nonacidic leaching conditions, the metals will be converted to substantially nonleachable forms.

A method of treating solid hazardous waste containing unacceptable levels of leachable metals selected from the group consisting of lead and cadmium, the method comprising the steps of mixing the solid waste with at least one first agent selected from the group consisting of magnesium oxide, magnesium hydroxide, reactive calcium carbonates and reactive magnesium carbonates, and at least one additional agent selected from the group consisting of triple superphosphate, ammonium phosphate, diammonium phosphate, phosphoric acid, boric acid and metallic iron so that under both acidic and nonacidic leaching conditions, the metals in the mixture will be converted to substantially non-leachable forms.

A non-hazardous solid waste mixture which may be safely disposed of in a landfill, comprising a solid hazardous waste containing unacceptable levels of leachable metals selected form the group consisting of lead and cadmium, mixed with at least one first agent selected from the group consisting of magnesium oxide, magnesium hydroxide, reactive calcium carbonates and reactive magnesium carbonates, and at least one additional agent selected from the group consisting of triple superphosphate, ammonium phosphate, diammonium phosphate, phosphoric acid, boric acid, and metallic iron in quantities sufficient so that under both acidic and nonacidic leaching conditions, the metals will be converted to substantially nonleachable forms.

A method of treating solid hazardous waste containing unacceptable levels of leachable metals selected from the group consisting of lead and cadmium, the method comprising the steps of mixing the solid waste with at least one first agent selected from the group consisting of magnesium oxide, magnesium hydroxide, reactive calcium carbonates and reactive magnesium carbonates, and at least one additional agent selected from the group consisting of triple superphosphate, ammonium phosphate, diammonium phosphate, phosphoric acid and boric acid so that under both acidic and nonacidic leaching conditions, the metals in the mixture will be converted to substantially non-leachable forms.

A non-hazardous solid waste mixture which may be safely disposed of in a landfill, comprising a solid hazardous waste containing unacceptable levels of leachable metals selected from the group consisting of lead and cadmium, mixed with at leas tone first agent selected from the group consisting of magnesium oxide, magnesium hydroxide, reactive calcium carbonates and reactive magnesium carbonates, and at least one additional agent selected from the group consisting of triple superphosphate, ammonium phosphate, diammonium phosphate, phosphoric acid and boric acid in quantities sufficient so that under both acidic and nonacidic leaching conditions, the metals will be converted to substantially nonleachable forms.

A method of treating solid hazardous waste containing unacceptable levels of leachable metals selected from the group consisting of lead and cadmium, the method comprising the steps of mixing the solid waste with at least one buffering agent, and further mixing it with at least one additional agent selected from the group consisting of triple superphosphate, ammonium phosphate, diammonium phosphate, phosphoric acid, boric acid and metallic iron so that under both acidic and nonacidic leaching conditions the metals in the mixture will be converted to substantially nonleachable forms.

A nonhazardous solid waste mixture which may be safely disposed of in a landfill, comprising a solid hazardous waste containing unacceptable levels of leachable metals selected from the group consisting of lead and cadmium, mixed with at least one buffering agent and further mixed with at leas tone additional agent selected from the group consisting of triple superphosphate, ammonium phosphate, diammonium phosphate, phosphoric acid, boric acid, and metallic iron in quantities sufficient so hat under both acidic and nonacidic leaching conditions, the metals will be converted to substantially nonleachable forms.

A method of treating solid hazardous waste containing unacceptable levels of leachable metals selected from the group consisting of lead, cadmium and zinc, the method comprising the steps of mixing the solid waste with at least one first agent selected from the group consisting of magnesium oxide, magnesium hydroxide, reactive calcium carbonates and reactive magnesium carbonates, and at least one additional agent selected from the group consisting of triple superphosphate, ammonium phosphate, diammonium phosphate, phosphoric acid, boric acid and metallic iron so that under both acidic and nonacidic leaching conditions, the metals in the mixture will be converted to substantially non-leachable forms.

A non-hazardous solid waste mixture which may be safely disposed of in a landfill, comprising a solid hazardous waste containing unacceptable levels of leachable metals selected from the group consisting of lead, cadmium and zinc, mixed with at leas tone first agent selected from the group consisting of magnesium oxide, magnesium hydroxide, reactive calcium carbonates and reactive magnesium carbonates, and at least one additional agent selected from the group consisting of triple superphosphate, ammonium phosphate, diammonium phosphate, phosphoric acid, boric acid, and metallic iron in quantities sufficient so that under both acidic and nonacidic leaching conditions, the metals will be converted to substantially nonleachable forms.