Sorption and biodegradation of tetracycline by nitrifying granules and the toxicity of tetracycline on granules

Autor: Xin-Hua Wang, Muhe Diao, Zhen Qi, Shu-Guang Wang, Su-Fang Xing, Yijing Shi, Xingchen Zhao, Mingming Gao
Rok vydání: 2011
Předmět:
Zdroj: Journal of Hazardous Materials. 191:103-109
ISSN: 0304-3894
DOI: 10.1016/j.jhazmat.2011.04.048
Popis: This paper examines the simultaneous sorption and biodegradation performance of tetracycline (TC) by the nitrifying granular sludge as well as the short-term exposure toxicity of TC. The removal of TC was characterized by a quick sorption and a slow process of biodegradation. The adsorption process fits pseudo-second-order kinetic model, with a complex mechanism of surface adsorption and intra-particle diffusion. Both temperature and mixed liquor suspended solid (MLSS) influenced TC sorption to the granules. TC biodegradation was enhanced with the increase of COD and NH 4 + –N concentrations, with except of the NH 4 + –N concentrations higher than 150 mg/L. With the ATU addition, TC degradation was weakened remarkably, indicating a synergistic effect of multiple microbes. Results of the short-term exposure (12 h) effects showed that the respirometric activities of the microbes decreased greatly. The addition of TC also decreased the rate of NH 4 + –N utilization considerably, with the half saturation constant ( K s ) increasing from 297.7 to 347.2 mg/L.
Databáze: OpenAIRE