城市污水厂污泥内循环自热高温微好氧消化的处理

Internal circulation autothermal thermophilic aerobic digestion for sewage sludge treatment

利用一种新型的内循环自热式污泥高温微好氧消化装置对城市污泥进行消化处理。通过在反应器中增加内筒的方法,使得内筒中污泥通过搅拌器的提升作用在内外筒之间循环以提高消化速率。结果表明,增加内筒之后,消化系统的污泥VS去除率在第16天达到了41.52%,而未添加内筒的反应器污泥到第20天时仍未到达稳定化水平。因此,加了内筒的单段式ATAD消化反应器与不加内筒的单段式ATAD消化反应器相比可以使得污泥更快地达到稳定状态。另外,与没有内筒相比,增加内筒后反应器顶部和底部的ORP和pH值均维持较高水平,消除了曝气死角。增加内筒后,顶部和底部污泥上清液中SCOD、VFA、TN、NH+4-N和TP浓度基本保持一致,而没有内筒则相差较大,表明增加内筒后,反应器内污泥混合更加均匀。

In order to improve the efficiency of sludge digestion,an internal circulation autothermal thermophilic aerobic digestion with an inner cylinder was investigated. The sludge was cycled between inner and outer cylinder. The results showed that in internal circulation autothermal thermophilic aerobic digestion（ATAD） system,the removal of volatile solids（VS） at 16 d was 41. 52%. At 20 d,the removal of VS was increased 11. 39%than no internal circulation. With the inner cylinder,the value ofORP and pH both in the top and bottom maintained in a higher level,the anaerobic condition was relieved. The pH,ORP,NH^＋4-H,SCOD,TVFA,TN and TP concentrations in the top of reactor were in accordance with those in the bottom. The sludge could be mixed more homogeneous with the inner cylinder.