Patent ID: 7338429

Claim:
A method for direct solidification and stabilization of liquid hazardous wastes containing up to 100,000 mg/L of arsenic, wherein the method comprises the steps of: (a) adding between about 0.04 and 0.05 liter of 30% hydrogen peroxide solution per liter to a liquid hazardous waste contaminated with arsenic, with continuous mixing; (b) subsequent adding between about 0.15 and 0.175 kg of calcium oxide per liter to the waste obtained in step (a), with continuous mixing; (c) subsequent adding between about 0.175 and 0.2 kg of ferric sulphate per liter to the waste obtained in step (b) with continuous mixing and adding between about 0.07 and 0.1 kg of additional metal bearing waste per 1 kg of the liquid waste to the waste obtained in step (b); (d) subsequent adding between about 1.1 and 1.25 kg of portland cement per liter to the waste obtained in step (c) with continuous mixing to obtain a homogenized slurry; and (e) curing the homogenized slurry obtained in step (d) to get desired solidified and stabilized mass, wherein the method is carried out in a single vessel, thereby solidifying and stabilizing the liquid hazardous waste.