CLEANING METHOD OF HOLLOW FIBER MEMBRANE

To provide a cleaning method of a hollow fiber membrane capable of dissolving clogging and the like causing deterioration of filtration ability of the hollow fiber membrane, even for the hollow fiber membrane which filters waste liquid of nutritious liquid containing not only various germs but also organic material such as fertilizer in plenty because being used for nutritious liquid culture.SOLUTION: A cleaning method of a hollow fiber membrane 11 which is put into practice on a filter apparatus 1 for filtering waste liquid of nutritious liquid culture with a hollow fiber membrane includes a flushing process of purging the raw water side on the hollow fiber membrane abutted on waste liquid with waste liquid at a flow rate more than that upon filtration and a heating and pressing impregnation process of sending cleaning liquid heated to 25 to 45°C to the filter apparatus at 0.1 to 1.0 MPa, a soaking and putting process of leaving the cleaning liquid standing to keep 0.1 to 1.0 MPa and a circulation process of sending liquid so as to circulate the cleaning liquid heated at 25 to 45°C to the filter apparatus.SELECTED DRAWING: Figure 1 【課題】養液栽培にて使用されることにより、雑菌だけでなく肥料などの有機物も多く含まれる養液の排液を濾過した中空糸膜に対しても、中空糸膜の濾過能力の低下の原因となる目詰まりなどを解消することができる中空糸膜の洗浄方法を提供する。【解決手段】養液栽培の排液を中空糸膜にて濾過する濾過装置１で実施される中空糸膜１１の洗浄方法であって、前記排液と当接する前記中空糸膜における原水側を前記排液にて濾過時より多い流量で掛け流すフラッシング工程と、２５〜４５℃に加温された洗浄液を０．１〜１．０ＭＰａにて前記濾過装置に送液する加温加圧含浸工程と、前記洗浄液を０．１〜１．０ＭＰａに保って静置する漬け置き工程と、２５〜４５℃に加温された前記洗浄液を前記濾過装置に循環するように送液する循環工程とを備える中空糸膜の洗浄方法。【選択図】図１