| 摘要 |
<p>PURPOSE:To effectively remove COD components which are difficult to be decomposed in organic waste water treatment using a separation membrane by feeding a concentrate concentrated by a BO membrane (reverse osmosis membrane) to an electrolyzer and decomposing it in the electrolyzer. CONSTITUTION:When organic waste water such as night soil and domestic waste water is treated, feed water 5 is fed into a biological reaction tank 1, it is mixed with active sludge in the tank 1, being biologically decomposed, and treated water 6 thus obtained is sent to the 1st membrane device 2. Suspension such as the active sludge contained in the treated water 6 is separated there by a separation membrane which is an ultrafiltration membrane or a precision filtration membrane. Biologically treated water 7 which remains in the membrane device 2 and in which the suspension is concentrated is returned to the biological reaction tank 1. On the other hand, membrane permeated water 8 is sent to the 2nd membrane device 3. The membrane permeated water permeating through an RO membrane is taken out as treated water 9, and also a concentrate 10 remaining in the membrane device 3 is sent to an electrolyzer 4 to remove COD components, etc.</p> |
