Method of integration of concentration-dehydration and aerobic air-drying of sewage sludge

Abstract

A method of integration of concentration-dehydration and aerobic air-drying of sewage sludge comprises the following steps: (a) conditioning by an organic agent (); (b) gravitationally concentrating () the residual sludge conditioned by the organic agent; (c) conditioning by inorganic agents (); (d) mechanically dehydrating (); (e) crushing and dispersing (); and (t) aerobically air-drying (). The method has the following advantages: (i) to improve the sedimentation performance of the residual sludge, thus improving the concentration efficiency of sludge, reducing the concentrating time and reducing the volume of the concentrating pool; (ii) to reduce the volume of the dehydrated sludge correspondingly, thus reducing the subsequent heat treatment load; (iii) to have low energy consumption for drying; (iv) the sludge granules moving at low speed during the drying process, thus being produced stably and securely without powder; (v) the dried exhaust air can reach environmental-friendly standard discharge after being washed by water; (vi) the output sludge granules are not compact, which is good for reclamation.