| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an oil-water separation method of oil-containing scum capable of performing oil-water separation regardless of the properties of the oil-containing scum.SOLUTION: An oil-water separation method of oil-containing scum includes a step of selecting a polyoxyalkylene alkyl ether on the basis of (a) to (c) corresponding to the viscosity of the oil-containing scum and adding the selected polyoxyalkylene alkyl ether to the oil-containing scum where: (a) polyoxyalkylene alkyl ether having an HLB value of 10-13.5 when viscosity at 20°C is less than 1,000 mPa s; (b) polyoxyalkylene alkyl ether having an HLB value of 10-13.5 and/or polyoxyalkylene alkyl ether in which an alkyl group is derived from a secondary alcohol when viscosity at 20°C is 1,000 mPa s or higher and less than 2,000 mPa s; and (c) polyoxyalkylene alkyl ether in which an alkyl group is derived from a secondary alcohol when viscosity at 20°C is 2,000 mPa s or higher.</p> |
