TREATMENT METHOD FOR ARSENIC-CONTAINING WASTEWATER AND ARSENIC REMOVING APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a treatment method for sufficiently removing suspended fine particles and a dissolved arsenic component from wastewater at once, and an arsenic removing apparatus suitable for carrying out the method.;SOLUTION: An acidic FeCl₃ aqueous solution 12 is added to wastewater 1, which contains insoluble suspended fine particles and the dissolved arsenic component (arsenic ions, arsenous ions, or the like) in an amount bringing hydrogen ion concentration (pH) to 2-below 6. Next, an NaOH aqueous solution 10 is added to the wastewater 1 to neutralize the same to form a precipitate of Fe(OH)₃, and the suspended fine particles and the dissolved arsenic component are coprecipitated along with Fe(OH)₃ as an arsenic-containing precipitate. Thereafter, the waste water 1 is subjected to solid liquid separation to be separated into the supernatant liquid and the arsenic-containing precipitate.;COPYRIGHT: (C)2005,JPO&NCIPI