| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a reduction system of waste sludge capable of effectively reducing waste sludge generated by treating organic wastewater by microorganisms. <P>SOLUTION: The reduction system of waste sludge generated by treating organic wastewater by microorganisms using electrolytic treatment includes following processes. In a first process, activated sludge containing wastewater treated by microorganisms in an aeration tank is concentrated by a gravity settling method in a settlement tank so that solid concentration in the activated sludge becomes 0.3-2 wt.%, the concentrated sludge is separated from a clear supernatant liquid, and part of the concentrated sludge is returned to the aeration tank. In a second process, the residual concentrated sludge is taken as the waste sludge, 0.1-3 wt.% of a chloride is added to the waste sludge while adding acid thereto to adjust it at pH 2-6. In a third process, the electrolytic treatment is applied to the waste sludge using an electrode in the electrolytic tank with a current density of 1-40 mA/cm<SP>2</SP>, and microorganisms in the waste sludge are wiped out. In a forth process, the electrolytically treated waste sludge is returned to the aeration tank again. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
