Study On Sludge Treatment With Internal Circulation Sludge Thickening And Digestion (ICSTD) Reactor

With the development of wastweater treatment in china, together with the resultant increase of sewage sludge, sludge treatment and disposal more and more public concern. As the problems such as too low loading, too long digestion time, hige investment and complex operation and management,are exist for current anaerobic sludge treatment. A new kind of anaerobic sludge digestion reactor named Internal Circulation Sludge Thickening Digestion (ICSTD) reactor treatment problem is developed against abovementioned problems. In this thesis are described in details and influencing factors of anaerobic sludge digestsion, and the model and operation mechanisms of ICSTD reactor are introduced.The experimented contents include the reactor startup mesophilic condition (35 ℃) and the operating effects under normal condition, with emphases thickening and digestion function. The long operational results indicate that the organic content decreases to 23%～51% in the discharged sludge form initial 63%～69% in the influent sludge,and the degradation rate amounts to 36.5%～86.3%, organic loading amounts to 9.68kgVS/m3.d and HRT amounts to 3.1d,the degradation percentage of organics is 79%,which is equal to or even exceeds the organic degradation rate of high loading digestor.Given 98.3% water content of influent sludge and 54.8d of SRT ,the water content for discharged sludge is around 90%,showing a better thickening effect than ordinary thickener(water content of discharged sludge is about 97.5%～98%) .It is perhaps because sludge digestion and sludge thickening have been enhanced for each other. The dynamics model of ICSTD deducted and relevant dynamics parameters are defined. In summary, the experimented study of ICSTD reactor has provided effective reference date to its design and operation and is helpful to practiced application and farther study.