| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a biological treatment method and apparatus which can decompose hardly decomposable substances, such as a surfactant having an EO chain, by biological treatment alone to obtain a treated liquid from which the hardly decomposable substances have been highly removed. <P>SOLUTION: A biological treatment tank which receives wastewater containing hardly decomposable surfactants, such as APE (polyoxyethylene alkylphenyl ether), and the like, and biologically treats them under aerobic condition is divided into two or more reaction tanks, and microorganism-carrying carriers are added to at least one of the reaction tanks to perform aeration. The biological treatment tank 1 comprises a first reaction tank 10 which has an air diffusion pipe 11 and performs aeration, and a second reaction tank 20 which has an air diffusion pipe 21 and is filled with the carriers 12. High concentrations of low growth rate bacteria decomposing the surfactants etc. are held on the carriers 12 in the second reaction tank 20 to biologically decompose the hardly decomposable surfactants etc. contained in effluent discharged from the first reaction tank 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
