<；P>；PROBLEM TO BE SOLVED: To provide a biological reaction apparatus which can execute microbiological treatment without agitation by a blower, achieve energy saving, and improve biological reaction efficiency by increasing water temperature in winter and producing and utilizing a large amount of various bubbles. <；P>；SOLUTION: In a bubble-mixing microorganism adhesion tank 40, micro-nano bubbles generated from a micro-nano bubble generator 6, nano bubbles generated from a nano bubble generator 36, microorganisms, and raw wastewater 1 are mixed to make mixed water. In a biological reaction tank 10, the mixed water supplied from the bubble-mixing microorganism adhesion tank 40 is made to flow into a passage, and subjected to biological reaction to make treated water. In a measurement tank 19, the water temperature and quality of the treated water supplied from the biological reaction tank 10 are measured. A water quality controller 28 and a water temperature controller 29 control the operation of the micro-nano bubble generator 6 and the nano bubble generator 36 from the water temperature and quality of the treated water measured in the measurement tank 19. <；P>；COPYRIGHT: (C)2008,JPO&INPIT
