Kinetic Study of Treatment of Reactive Dye Using Coal Fly Ash as a Supporting Medium in a Biofilm Reactor

• Main Authors: Chih-hao Hsu, 許志豪
• Other Authors: Yen-Hui Lin
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/62517049385562718988

碩士 === 中臺科技大學 === 安全與防災科技研究所 === 100 === The mechanisms of fixed-biofilm kinetic model included the surface diffusion of reactive black 5 on fly ash particles, mass transfer in liquid / biofilm interface, and Monod kinetics. The mechanisms to remove reactive dye were adsorption and biodegrdation in fixed-biofilm reactor using fly-ash as a supporting medium. In this study, a laboratory-scale fixed biofilm reactor using fly ash particles as supporting media was setup to treat reactive dyes (reactive black 5) for decolorization and the kinetic model system was developed. The batch tests were used to determine biokinetic parameters. The yield coefficient (Y) was 0.525 mg cell/mg RB5. The Funalia trogii (F.trogii) cells specific growth rate (mm) was 7.256 day-1. The maximum specific utilization rate was 13.82 mg RB5/mg cell-day. The half-saturation constant (Ks) was 0.28 mg RB5/L. The decay coefficient of F. trogii cells (b) was 0.0568 day-1. The diffusion coefficient of RB5 (Df) obtained from empirical formula was 0.169 cm2/day. The mass transfer coefficient in the liquid/biofilm interface was 237.4 cm2/day. The Langmuir adsorption isotherm obtained from the batch kinetic tests to determine adsorption amount parameter (qm) and (Ka), which was 0.77 (mg/g) and 9.58x10-3 (L/mg), respectively. The working volume of completely-mixed biofilm reactor was 7 L. The flow rate of influent was 20 L, which yield the hydraulic retention time was 8.4 h. The removal efficiency of RB5 was about 42% when the F. trogii cells reached a maximum growth phase. The experimental results showed a good agreement with model simulation. The approaches of experiment and modeling can be applied to scale-up the fixed-biofilm reactor using fly-ash as a supporting medium to treat reactive dyes, which achieves the purpose of reclamation of coal fly ash.