Hydrogenotrophic denitrification in a packed bed reactor: Effects of hydrogen-to-water flow rate ratio

• Published in: Bioresource technology 2010-06, Vol.101 (11), p.3940-3946
• Main Authors: Lee, J.W., Lee, K.H., Park, K.Y., Maeng, S.K.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Correlation; Dissolution; Drinking water; Flow rate; Fundamental and applied biological sciences. Psychology; Guidelines; Hydraulic retention time; Hydraulic retention time (HRT); Hydrogen - chemistry; Hydrogen flow rate; Hydrogenotrophic denitrification; Kinetics; Nitrates; Nitrates - chemistry; Packed bed reactor (PBR); Reactors; Solubility; Water - chemistry
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2010.01.022

Hydrogen dissolution and hydrogenotrophic denitrification performance were investigated in a lab-scale packed bed reactor (PBR) by varying the hydrogen flow rate and hydraulic retention time (HRT). The denitrification performance was enhanced by increasing the hydrogen flow rate and HRT as a result of high dissolved hydrogen concentration (0.39 mg/L) and utilization efficiencies (79%). In this study, the hydrogen-to-water flow rate ratio ( Q g/ Q w) was found to be a new operating factor representing the two parameters of hydrogen flow rate and HRT. Hydrogen dissolution and denitrification efficiency were nonlinearly and linearly correlated with the Q g/ Q w, respectively. Based on its excellent linear correlation with denitrification efficiency, Q g/ Q w should be greater than 2.3 to meet the WHO’s guideline of nitrate nitrogen for drinking water. This study demonstrates that Q g/ Q w is a simple and robust factor to optimize hydrogen-sparged bioreactors for hydrogenotrophic denitrification.