METHOD AND APPARATUS FOR TREATING WASTEWATER CONTAINING CATIONIC SURFACTANT

摘要

When recovering water by performing a reverse-osmosis-membrane separation treatment on wastewater containing a cationic surfactant such as process wastewater from the electronics industry, high-quality treated water is obtained consistently over the long term while preventing blockage of the reverse-osmosis membrane caused by the cationic surfactant. A reverse-osmosis-membrane separation treatment is performed using a first reverse-osmosis-membrane separation device (3) on wastewater containing a cationic surfactant such as process wastewater from the electronics industry after first adjusting the same to a pH of 3-5, a reverse-osmosis-membrane separation treatment is performed using a second reverse-osmosis-membrane separation device (4) on permeated water from the first reverse-osmosis-membrane separation device (3) after first adjusting the same to a pH of 6.5-10.5, and the permeated water from the second reverse-osmosis-membrane separation device (4) is recovered as treated water.

主权项

1. A method for treating wastewater containing a cationic surfactant, the method comprising:
a first reverse-osmosis-membrane-separation step in which a pH of wastewater containing a cationic surfactant is controlled to be 3 to 5 and the wastewater containing a cationic surfactant is subsequently subjected to a reverse-osmosis-membrane-separation treatment; and a second reverse-osmosis-membrane-separation step in which a pH of reverse-osmosis-membrane permeate water produced in the first reverse-osmosis-membrane-separation step is controlled to be 6.5 to 10.5 and the reverse-osmosis-membrane permeate water is subsequently subjected to a reverse-osmosis-membrane-separation treatment.