| Title |
The Effect of Oxygen Penetration into the Floc on Operating Parameters of Pure - Oxygen Activated Sludge Process |
| Authors |
최재환 ; 김영진 ; 김인수 ( Jae Hwan Choi ; Young Jin Kim ; In S . Kim ) |
| Abstract |
The effect of oxygen penetration into the microbial floc on the performance of activated sludge process was investigated. Two lab-scale completely mixed biological reactors maintaining dissolved oxygen (DO) concentrations at 2㎎/L and 10㎎/L were run under the same environmental conditions. For high DO level(10㎎/L), about 10% of additional reduced sludge production and slightly improved organic removal efficiency were observed compare to the low DO level(2㎎/L). In order to verify the difference of performance between the two completely mixed biological reactors, the diffusion model for oxygen transfer through bacterial floc was derived by adapting the concept that bacterial floc react as spherical porous catalyst. The data of oxygen uptake rate(SRT variation) used in the model was from the study of Clark et al (1971), and 100㎛ of floc diameter was assumed. The application of diffusion model. to the reactor operational data indicated that complete penetration of oxygen to the center of floc was occurred for the range of 1.0∼13day of SRT in the reactor of high DO level (10㎎/L). However, significant oxygen concentration drop was monitored according to SRT changes in the reactor of low DO level. In the case of low DO level, the concentration of active biomass calculated from the oxygen penetration model was lower than that of high DO level. In order to prove precisely the effect of D0 concentrations on the activated sludge process with diffusion model, it is recommended to measure the floc size and oxygen uptake rate in the future research. |