High-rate anaerobic digestion of thermally hydrolyzed wasted sludge (THWS) with high-strength ammonia

• Published in: Journal of material cycles and waste management 2018, Vol.20 (1), p.516-524
• Main Authors: Park, Seyong, Han, Seong Kuk, Oh, Dooyoung, Kim, Daegi, Kim, Ho, Yoon, Young-Man
• Format: Article
• Language: English
• Subjects: Ammonia; Anaerobic digestion; Bioreactors; Civil Engineering; Continuously stirred tank reactors; Engineering; Environmental Management; Fluidized bed reactors; Fluidized beds; Gas production; Methane; Microorganisms; Oil and gas production; Original Article; Reactors; Refuse as fuel; Sludge; Sodium; Stripping; Toxicity; Waste Management/Waste Technology; Wastewater
• ISSN: 1438-4957; 1611-8227
• DOI: 10.1007/s10163-017-0613-5

In this study, the anaerobic digestion of thermally hydrolyzed wasted sludge with high-strength ammonia was evaluated through ammonia-stripping and diverse types of anaerobic-digestion reactors. Although anaerobic digestion was conducted after ammonia-stripping and removal, anaerobic-digestion inhibition occurred due to the problem of the toxicity of sodium. Therefore, the sodium concentration should be maintained at lower than inhibitory concentration for effective anaerobic digestion. The results of the operating reactors, gas production amount, methane content, organic-matter removal efficiency, and methane yield were high in the order of the fluidized bed reactor (FBR), upflow anaerobic sludge blanket reactor, and continuously stirred tank reactor types. As the microorganism concentrations in the FBR type were more than twice higher than those in the other reactors, the FBR type was able to keep the microorganism concentrations high, and the microbial proximity between the hydrogen-producing microorganisms and the hydrogen-consuming microorganisms was closest in the FBR type. Therefore, the reactor type for the efficient anaerobic digestion of wastewater containing high-concentration ammonia nitrogen is the FBR type.