Study On Wastewater Treatment Using Swimming-bed Biofilm Reactor

Wastewater biological treatment needs no chemical, which is helpful to avoid second pollution, and involved reaction is mild, and the microbe can be gotten everywhere. All of these make it become one of the most important methods used to decontaminate wastewater. Swimming-bed biofilm reactor is a kind of novel biofilm reator. In comparison with conventional biological treatment systems, SBBR have many advatages such as higher COD removal, a shorter time of starting, reducing the area of the land, operating steadily, controlling easily and so on.Swimming-bed biofilm reactor was used to treat simulative wastewater. The removal efficiency of COD and nitrogen were studied, in additiong, the principle of simultaneous nitrification and denitrification (SND) was studied. And the new kind of soft carrier was proved that biofilm was easy to grow on it.The experiment last 14 months and the results were desirable. Firstly, the performance of SBBR to treat domestic wastewater was investigated in bench-scale test. The optimal parameter HRT of 6h, DO of 3-4mg/l, C/N ration of 20 was determined. Secondly, the operational characteristics of SBBR process in the course of treating high-strength organic wastewater was studied. Restult shows that the average COD removal efficiency achieved 75% at volumetric loadings up to 8kgCOD/(m3-d). And average TN and NH4+-N removal efficiency achieved more than 50% at volumetric loading less than 5 kgCOD/(m3d). At last, it is proved that SBBR can realize the simultaneous nitrification and denitrification biological nitrogen removal technique.