Process optimization and energy analysis of vacuum degasifier systems for the simultaneous removal of dissolved methane and hydrogen sulfide from anaerobically treated wastewater

Water Research
Eunseok LeeJaeho Bae

Abstract

The control of dissolved methane (CH4) and hydrogen sulfide (H2S) emissions in anaerobic effluents is essential for minimizing the environmental implications of greenhouse gases, odor, and carbon footprint, as well as for preventing energy loss in the form of unrecovered dissolved methane. This study assessed the feasibility of a vacuum degasifier for the removal of CH4 and H2S from staged anaerobic fluidized membrane bioreactor (SAF-MBR) effluent. The optimization results showed that the efficiency of the nozzle fitted degasifiers were superior to the media packed ones. In three-stage vacuum degasifiers at a -0.8 bar vacuum pressure, H2S removal was mostly pH dependent and 88% removal efficiency was achieved with an initial concentration of 13.6 mg/L. Methane removal was dependent primarily on the number of degasifier units, and approximately 94% efficiency was achieved in a three-stage degasifier. Energy balance analysis showed that energy production exceeded the system energy requirements with 0.05-0.07 kWh/m3 of surplus energy. These results provide deep insights into this new technology for simultaneous removal of dissolved CH4 and H2S, which can be referred for potential future applications.

Related Concepts

Related Feeds

Bioreactors (ASM)

Bioreactors are important devices or systems that utilize living cells or enzymes for a chemical process. These devices carefully control and monitor the environment factors such as pH, nutrients level, and temperature, which can affect the yield in a given process. Discover the latest research here.