| 摘要 |
<p>Provided are a method for immersion-type washing of a separation membrane device and a system for immersion-type washing of a separation membrane device with which it is possible to simply and reliably remove adherents from the surface of the separation membrane device. The substance to be removed from the membrane surface of a separation membrane device (3) can be removed by a simple procedure, without requiring large volumes of chemicals, by introducing a chemical solution from the filtration water side of the separation membrane device (3) while said separation membrane device (3) is disposed inside a tank (2). Moreover, the chemical solution is introduced such as to satisfy the relationship -0.375X + 30 = Y = 0.5X + 80, wherein the pre-washing membrane differential pressure during filtration is X (kPa) and the membrane differential pressure with chemical solution introduced during back-pressure rinsing is Y (kPa). The chemical solution can penetrate to the outer surface in the direction of membrane thickness, even where the substance to be removed is firmly deposited. Moreover, it is possible to obtain sufficient time for reacting the substance to be removed and the chemical solution. As a result, the substance to be removed can be removed from the entire separation membrane device.</p> |
