MIZUTANI Satoshi Kyoto University, Environment Preservation Center, Instructor, 環境保全センター, 助手 (80283654)
TAKATSUKI Hiroshi Kyoto University, Environment Preservation Center, Professor, 環境保全センター, 教授 (80026228)
|Budget Amount *help
¥3,500,000 (Direct Cost : ¥3,500,000)
Fiscal Year 1998 : ¥1,400,000 (Direct Cost : ¥1,400,000)
Fiscal Year 1997 : ¥2,100,000 (Direct Cost : ¥2,100,000)
Recently Persistent Organic Pollutants (POPs) were defined as organic pollutants, which have 4 characteristics ; persistency, bioaccumulation, volatility and toxicity. They are becoming environmental pollutants for which a global action has to be taken. It has been clarified that POPs and the mixture with POPs cause various problems, such as cancer, immunity disorder, reproductive defects and deformities, if human beings are exposed to them acutely and chronically. This research investigated the actual conditions of POPs contained in waste and their leaching behavior. In particular, we experimentally analyzed PCBs and PCDDs/DFs in shredder dust which are residues of shredder-style recycling of waste cars and waste home electric appliances and discussed their leaching behavior through analysis of influential leaching factors on PCBs.
PCBs were detected at the maximum level of 24 mg/kg in shredder dust and proven to be contained in the ppm order. When humic acid and liner alkylbenzene sulfonate (LAS), which is a surface active agent, exist in shredder dust, the ROBs leaching concentration rose. The leaching test using LAS of 1000 ppm as solvent showed that the PCBs leaching concentration increased by 70 times compared to that of the test using distilled water as solvent. Concerning a method of leaching test, the difference was recognized between solid-liquid separating methods. In the centrifugal separating method, the POB leaching concentration was 19 mug/L, which is much higher than the value of the filter separating method, 5.7 mug/L.On the other hand, the profiles of PCB homologues in the centrifugal method and the filtering one were almost same. The particle diameter of leachate in the centrifugal separating method was less than 0.45 mum, while that in the filter separating method was less than 0.08 mum. These data indicated that the particle diameter distribution of particulates in leachate is a factor to influence on the ROB leaching concentration.