Characterization of Methane Emissions From Johkasou and Investigation Into a Mitigation Strategy Using Continuous Internal Recirculation

Key Points

• The research aims to analyze methane emissions from household treatment systems and evaluate a mitigation strategy.
• Characterization of CH4 emissions using oxidation-reduction potential (ORP) and nitrate nitrogen levels.
• Implementation of continuous internal recirculation during primary treatment.
• Assessment of CH4 reduction under varying ORP and nitrate nitrogen concentrations.
• CH4 emissions were reduced by approximately 50% under optimal ORP and nitrate nitrogen conditions.
• Higher ORP (greater than -150mV) and nitrate nitrogen concentration (over 9mg/L) correlated with reduced emissions.
• Multiple factors including metabolic inhibition and denitrification processes influenced CH4 reduction.