Patent ID: 8834726
Filing Date: 2014-09-16
Classification: C01B,C02F,E21B,Y10S

Abstract:
1. A method comprising: contacting a metal-containing wastewater comprising barium with a source of sulfate ions under acidic oxidizing conditions: precipitating at least 90% of the barium from the metal-containing wastewater, in the form of barium sulfate; flocculating and removing the barium sulfate from the stream of metal-containing wastewater, to form barium sludge and a first treated wastewater, wherein the barium sludge is non-hazardous according to the USEPA TCLP leachate test; contacting the first treated wastewater with a source of carbonate ions; precipitating one or more metal carbonates from the first treated wastewater after contact with the source of carbonate ions, to form a mixture of second treated wastewater and one or more metal carbonates; contacting the mixture with a source of hydroxide ions; and precipitating one or more metal hydroxides from the second treated wastewater.