Influencing effect of intra-granule mass transfer in expanded granular sludge-bed reactors treating an inhibitory substrate.
Two expanded granular sludge-bed (EGSB) reactors (superficial velocity u s=6.0 and 9.0m/h) were used to treat an inhibitory substrate phenol. The granule diameter (dp) increased with increasing organic loading rate (OLR) and u(s). At the OLRs of 1.67-4.44 kg phenol/m3 d, the accumulation of volatile fatty acids (VFAs) was insignificant; whereas at the OLR of 5.11 kg phenol/m3 d, both the accumulation of VFAs and the washout of large hollow granules (average dp=2.90-3.12 mm) occurred. The comparative experimental and simulated results showed that the proposed kinetic model is suitable for design and predicting purposes. The calculation results of mass transfer parameters (Thiele modulus, Biot number, diffusion layer thickness, and overall effectiveness factor) and parametric sensitivity analysis results (half-saturation constant Ks and dp) showed that the intra-granule mass transfer would lead to a more influencing effect than the external mass transfer on the overall substrate removal rate in EGSB reactors.
Chou
Hsin-Hsien
HH
Department of Environmental Engineering, Kun Shan University, Tainan County 710, Taiwan, ROC. envi1234@mail.ksu.edu.tw
Huang
Ju-Sheng
JS
Jheng
Jing-Hong
JH
Ohara
Reiko
R
D019149:Bioreactors; D003198:Computer Simulation; D007700:Kinetics; D010316:Particle Size; D019800:Phenol / Q000302:isolation & purification*; D015203:Reproducibility of Results; D012722:Sewage; D014865:Waste Disposal, Fluid
D012722:Sewage; D019800:Phenol