REUSING METHOD OF WASTE WATER

To provide a reusing method of waste water capable of reusing the waste water containing a surfactant and an oil by purification in a simple method.SOLUTION: In a reusing method of waste water where (a) a polymer coagulant (hereafter described as (a) component) having spinnability and (b) bentonite (hereafter described as (b) component) are mixed in the waste water and an aqueous layer is reused as water after standing,: the waste water containing a surfactant and an oil is mixed with the (b) component at a ratio of 5 pts.mass or more and 100 pts.mass or less to 1,000 pts.mass of the waste water; and the (a) component and the (b) component are mixed so that a mass ratio (b)/(a) becomes 100 or more and 3,000 or less.SELECTED DRAWING: None 【課題】界面活性剤と油とを含有する排水を簡便な方法で浄化して再利用できる、排水の再利用方法を提供する。【解決手段】排水に、（ａ）曳糸性を有する高分子凝集剤［以下（ａ）成分という］及び（ｂ）ベントナイト［以下（ｂ）成分という］を混合し、静置後、水層を水として再利用する、排水の再利用方法であって、排水が界面活性剤と油とを含有し、（ｂ）成分を、排水１，０００質量部に対して、５質量部以上１００質量部以下の割合で混合し、（ａ）成分と（ｂ）成分とを、（ｂ）／（ａ）の質量比が１００以上、３０００以下となるように混合する、排水の再利用方法。【選択図】なし