| 摘要 |
<P>PROBLEM TO BE SOLVED: To treat an insulating oil containing a polychlorinated aromatic compound such as PCB or the like without discharging wastewater to the outside environments by a method which scarcely causes effects on environments. <P>SOLUTION: The treatment method is a method for treating PCB-containing insulating oil without discharging oil washing wastewater to the outer environments and involves: a reaction step for decomposing PCB in the insulating oil by an alkali metal tert-butoxide; an insulating oil washing step for washing the oil subjected to the reaction, dissolving an alkali metal chloride, an alkali metal hydroxide produced by hydrolysis of the alkali metal tert-butoxide, and some of tert-butanol in the oil phase, and recovering the treated oil after separation of oil from water; an oil washing water purifying step for neutralizing the oil washing water separated from the treated oil, removing organic matter by adsorption, and removing inorganic salts; and a washing water circulation step for injecting the oil washing water again to the treated oil and again circulating and utilizing the water as washing water. <P>COPYRIGHT: (C)2003,JPO |
