PROBLEM TO BE SOLVED: To provide a method for enhancing biological digestion of wastewater sludge.SOLUTION: A method comprises: introducing wastewater 108 into a biological unit 116 to obtain and separate wastewater 121 having a reduced nutrient content, so as to obtain effluent 121 and waste activated sludge 122； contacting the waste activated sludge 122 with chlorine dioxide for a period of time sufficient to reduce a concentration of microorganisms, so as to obtain a state where a treated waste activated sludge 122 has a soluble COD concentration of 10% of the total COD concentration； and aerobically digesting the treated waste activated sludge 122 to obtain methane.SELECTED DRAWING: Figure 3【課題】廃水汚泥の生物学的消化を向上する方法を提供する。【解決手段】廃水１０８を生物学的ユニット１１６に導入し、減少した栄養素の含有量を有する廃水１２１を得て分離し、排水１２１および廃棄活性泥１２２を得て、微生物濃度を減少するのに充分な時間にわたって廃棄活性泥１２２を二酸化塩素と接触させ、処理済廃棄活性泥１２２が合計ＣＯＤ濃度の１０％の可溶性ＣＯＤ濃度を有する状態とする。更に処理済廃棄活性泥１２２を好気的に消化してメタンを得ることを含む方法。【選択図】図３
