Abstract: An apparatus for treating organic sludge by aerobic digestion has an aerobic digestion tank 1, a circulation line 6 provided with a pump for pumping circulated sludge, a liquid/gas ejector 7 for aspirating an oxygen-containing gas, which has been humidified, and for mixing it with the circulated sludge, a liquid/liquid ejector 8 for mixing the circulated sludge with sludge in a later step, a downward directing pipe 9 for passing downwards therethrough a gas/liquid mixture and an ozone-treated unit 31.

Abstract: An apparatus for treating organic sludge by aerobic digestion, in which the digestion can be realized efficiently at an improved rate of digestion of the organic sludge steadily for a long period of time, while preventing clogging of the flow path for supplying oxygen-containing gas, which apparatus comprises an aerobic digestion tank 1, a circulation line 6 provided with a pump for pumping the circulated sludge, a liquid/gas ejector 7 for aspirating the oxygen-containing gas, which has been humidified, and for mixing it with the circulated sludge, a liquid/liquid ejector 8 for mixing the circulated sludge with the sludge in a later step, a downward directing pipe 9 for passing downwards therethrough the flow of gas/liquid mixture and an ozone-treating unit 31, wherein the circulated sludge is mixed with an oxygen-containing gas in the liquid/gas ejector by jetting the circulated sludge into a throat 11 and passing the resulting mixture through the liquid/liquid ejector 8 and the downward directing pipe 9 to