WATER TREATMENT METHOD AND APPARATUS

• Main Authors: KAWAKAMI YU, TOTO MASANORI, TSUDA TAKASHI, OMORI DAISUKE, TANAKA AKIHIRO, MITARAI SHO
• Format: Patent
• Language: English; Japanese
• Published: 20.06.2019
• Subjects: CHEMISTRY; METALLURGY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

To provide a water treatment method and apparatus capable of keeping stable operation of filtering wash water by membrane processing.SOLUTION: A water treatment method includes a recovery step for recovering wash water that washes equipment and contains materials to be washed off, a membrane filtration step for filtering off the materials to be washed off with a porous membrane from the wash water recovered in the recovery step to clean the wash water, a reuse step for reusing the wash water cleaned in the membrane filtration step, and a regaining step for cleaning the porous membrane with a chemical agent when a permeating rate of the wash water through the porous membrane that has removed the materials to be washed off in the membrane filtration step decreases to a predetermined value or less. The porous membrane is a filter produced by stretching polytetrafluoroethylene and the chemical agent is caustic soda.SELECTED DRAWING: Figure 1 【課題】膜処理により洗浄水を濾過する運転を安定して継続し得る水処理方法及び装置を提供する。【解決手段】機器を洗浄し被洗浄物質を含有した洗浄水を回収する回収工程と、回収工程で回収した洗浄水を多孔質膜で濾過して被洗浄物質を除去し浄化する膜濾過工程と、膜濾過工程で浄化した洗浄水を再利用する再利用工程と、膜濾過工程で被洗浄物質を除去した多孔質膜の透過水量が設定値以下になった際に多孔質膜を薬剤にて洗浄する回生工程とを有し、多孔質膜は、ポリテトラフルオロエチレンを延伸加工したフィルタとし、薬剤は苛性ソーダとする。【選択図】図１