PURPOSE: To activate stagnant sewage without using chemicals by setting a water activating material having soil bacteria activity in stagnant sewage and circulating the sewage under pressure through a tank filter contg. a filter medium.
CONSTITUTION: Sewage is sucked up by a suction pump 2 from one side of the pond, lake, marsh, etc., (bond 9 in this case) and introduced into a tank filter 1 through a suction pipe 3 and a conveying pipe 4. The water filtered by the tank filter 1 is returned to the other side of the pond 9 through a conveying pipe 5 and a discharge pipe 6. A water activating material 8 is arranged close to the discharge part 7 of the pipe 6, and silicate-contg. stone 21 are uniformly distributed over the whole region of the pond 9. The water activating material 8 is composed of a material having soil bacteria activity or phenol and/or phenol exposed components.