Performance evaluation of oxygen, air and nitrate for the microaerobic removal of hydrogen sulphide in biogas from sludge digestion

Economic analysis of microaerobic removal of H2S from biogas in full-scale sludge digesters

“…Moreover, they reported dissolved sulfide removal when biogas recirculation was implemented, which was indeed consistent with Díaz et al (2011). Under equivalent oxygenation rates, Díaz et al (2010) reached similar efficiencies of H 2 S removal with both air and pure O 2 . However, they reported a significant decrease in the biogas CH 4 content with micro-aeration, due to the presence of N 2 .…”

“…As a result, the CH 4 concentration in biogas was 2%v. lower than in MA O2 and MA 95%O2 (Table 1), as reported by Díaz et al (2010). The consequent loss of efficiency of the engine (0.16%) was estimated according to Porpatham et al (2008), who reported a decrease of 0.9% in the efficiency of the spark-ignition engine when the CH 4 concentration was reduced from 70 to 59%v.…”

The Influence of Micro-Oxygen Addition on Desulfurization Performance and Microbial Communities during Waste-Activated Sludge Digestion in a Rusty Scrap Iron-Loaded Anaerobic Digester

“…During the first six periods, only negligible amounts (stabilized at around 5 mg) of sulphide oxidation products (S 2 O 3 2− , SO 4 2− ), were found in the liquid. Díaz et al [47] discovered that sulphate was found to be easily accessible for sulphate-reducing microorganisms, while organic sulphur in the form of proteins, or cell constituents, was only partly reduced, and a large portion left the bioreactor unchanged. However in P7, the amounts of sulphide oxidation products significantly improved to 23.97 mg.…”

A review on prospects and challenges of biological H2S removal from biogas with focus on biotrickling filtration and microaerobic desulfurization

“…From now on, the term "microaeration" will be used to generally refer to the process regardless air or oxygen is used. Hence, microaeration desulfurization refers to the process in which a small amount of air or oxygen is injected into anaerobic digesters to grow SOB, so that S 0 is formed as a result of desulfurization process (Díaz et al, 2010;Kobayashi et al, 2012). Due to the fact that desulfurization of the biogas is performed inside biogas digesters, periodic cleaning is inevitable to prevent clogging problems and avoids any decreases in the H2S removal efficiency.…”