| The objective of this research was to investigate the toxicity reduction efficiency of industrial wastewater by spraying with partial freezing technique. Before conducting the spray freezing experiments, wastewaters were partially frozen in beakers to observe the effects of freezing temperatures, dilutions and stirring. Full strength and diluted (1:10) pulp mill effluent and refinery wastewater were partially frozen (70%) at two different temperatures, with or without stirring. Ice and liquid samples were analysed for impurity and toxicity reduction. A range of 45% to 95% of the impurities (TOC, COD and color) were removed from the wastewaters, which produced ice samples with no toxicity. Freezing temperatures, dilutions and stirring had significant effect on impurity separation. Partial freezing in beakers showed higher separation efficiency for diluted wastewater with stirring at warmer freezing temperatures. (Abstract shortened by UMI.)... |
