Treatment of TNT red water by layer melt crystallization

Treatment of the red water, which is wastewater of 2,4,6- trinitrotoluene (TNT) manufacturing process has been explored using ice crystallization. This study focuses on the formation of ice crystals from the red water in a layer crystallizer under various operating conditions. Among the parameters which affect layer crystallization, attention was given to cooling rate, cooling temperature, sweating rate and concentration of the red water. The study highlights the effect of subcooling and growth rate on purity of the ice crystalline layers produced. After sweating, the COD value of crystalline ice layer was significantly reduced from 10,000 mg/L to below 20 mg/L. Most organic contaminants were removed in sweating fractions of 0.5. Eventually, the red water was treated by layer crystallization combined with the sweating process. (C) 2014 Elsevier B.V. All rights reserved.