2006 Volume 53 Issue 3 Pages 134-141
In Japan, large quantities of pesticides are stockpiled in many locations. The Japanese government aspires that these pesticides should be regulated by treating them as per the regulations of the Stockholm Convention which came into effect from the year 2004, controlling twelve persistent organic pollutants (POPs). Therefore, it has become mandatory to develop technologies that can effectively destroy these stockpiled pesticides safely and effectively. Having this in mind, in this study, the removal and elimination efficiency of DDTs, aldrin and BHC (HCHs) was investigated heating mixed samples of these pesticides in a tubular furnace coupled with a secondary combustion chamber, in presence of air or nitrogen. We observed no difference in the volatilization temperatures of these pesticides when the samples were heat-treated either under nitrogen or air. When the sample was heated to 600°C under a nitrogen atmosphere, an increase in the ratio of DDE in total DDTs was observed. About 90% of the aldrin was destroyed. BHC was volatilized almost completely at this temperature but did not disintegrate at all. A high removal rate was observed for all the chemicals when the flue gas from the tubular furnace was heated to 1,100°C in the secondary combustion chamber. However, the volatilization rate of BHC (HCHs) decreased when the oxygen concentration in the secondary combustion chamber was lowered. This study proves the effectiveness of a system designed to vaporize pesticides through heating in a furnace at high temperature followed by combustion of the flue gas.
