title: Entrapped cell system for decentralized hospital wastewater treatment: inhibitory effect of disinfectants.
abstract: This study aims to improve decentralized hospital wastewater treatment inhibited by disinfectants by using calcium alginate cell entrapment technique. The effects of disinfectant types (glutaraldehyde, povidone iodine (PI) and a potassium hydroxide solution) and disinfectant concentrations, cell entrapment conditions (cell-to-matrix ratios) and cell loadings were investigated. The batch experiments were conducted using synthetic wastewater with initial chemical oxygen demand (COD) of approximately 370 mg/L and acclimated activated sludge. Among three disinfectants, PI substantially affected the wastewater treatment efficiency (inhibition of 40%) while other disinfectants exhibited inhibition effects of less than 9%. The results also indicated that the entrapped cells obviously performed better than the free cells. The cell-to-matrix ratio of 1:20 (v/v) provided the highest treatment efficiency of 86% (inhibition of 9%) while the free cell system had inhibition of 47%. The system at the entrapped cell loading of 2000 mg/L performed the highest COD removal of 62% for ten-cycle sequencing batch operation. A scanning electron microscope image provided information on entrapped cell structure subjected to the disinfectant.
authors: Department of Chemical Engineering, Faculty of Engineering and Center of Excellence for Environmental and Hazardous Waste Management, Ubon Ratchathani University, Ubon Ratchathani, Thailand. ensumasi@ubu.ac.th
authors: Sumana
authors: S
authors: Siripattanakul-Ratpukdi
mesh_terms: D019149:Bioreactors; D004202:Disinfectants; D005976:Glutaral; D006761:Hospitals; D006878:Hydroxides; D007700:Kinetics; D017680:Potassium Compounds; D011206:Povidone-Iodine; D062065:Wastewater; D018508:Water Purification
chemical_list: D004202:Disinfectants; D005976:Glutaral; D006878:Hydroxides; D017680:Potassium Compounds; D011206:Povidone-Iodine; D062065:Wastewater; C029943:potassium hydroxide