| abstract |
Provided is a wastewater treatment device that can reduce the fluoride ion concentration in industrial wastewater to improve the recovery rate of purified water. A wastewater treatment device ( 1 ) includes a biological treatment unit ( 3 ) that decomposes and eliminates organic matter in wastewater by means of microorganisms, and a desalinization unit ( 4 ) that is provided downstream of the biological treatment unit ( 3 ) and eliminates salt-forming ionic components from within the wastewater. A pretreatment unit ( 2 ), which removes components, such as heavy metals or oil contained in the wastewater, which inhibit the function of the biological treatment unit ( 3 ) or the desalinization unit ( 4 ), is provided upstream of the biological treatment unit ( 3 ), and the pretreatment unit ( 2 ) is provided with a fluoride concentration reduction unit that reduces the concentration of fluoride ions in the wastewater by eliminating the fluoride ions from within the wastewater. |