| 摘要 |
<p>Provided is a filtering method for filtering raw water to produce filtered water, by subjecting a membrane module to a filtering operation using a pressure as a drive force. The filtering operation is composed of three modes of a raw water-side pressure filtration, a filtered water-side vacuum filtration, and a composite filtration combining the raw water-side pressure filtration and the filtered water-side vacuum filtration. The filtering method is characterized in that at least one of the raw water-side water quality, the membrane filtration flux and the membrane difference pressure is measured to switch one of the filtrations among the three modes to another filtration in accordance with the measured value.</p> |
