Type Ⅰ methanotrophs within WTTPs: Can integrate methane mitigation, biofuel production, and nitrogen removal?

摘要

Anaerobic digestion (AD) process has been widely adopted by wastewater treatment plant (WWTPs) for both waste minimization and biogas production as an alternative energy source. However, multiple obstacles limit the direct energy generation of the AD driven biogas. Furthermore, biological nitrogen removal processes are hindered by carbon source depletion resulting in excessive nitrogen concentrations in the effluent. Fortunately, methanotrophs can be the remedy to valorise the anaerobic digestion driven biogas to meet the targeted nitrogen concentration in the effluent. Methanotrophs have the ability to integrate methanol recovery from methane with denitrification. In this study, the potential for integrating type I methanotrophs within WWTPs was investigated using mixed culture enriched from WWTPs sludge and employing the nitrate rich final sedimentation effluent as the growth medium.