Deterministic processes guide long-term synchronised population dynamics in replicate anaerobic digesters

Microbial community dynamics in replicate anaerobic digesters exposed sequentially to increasing organic loading rate, acidosis, and process recovery

BACKGROUND Volatile fatty acid intoxication (acidosis), a common process failure recorded in anaerobic reactors, leads to drastic losses in methane production. Unfortunately, little is known about the microbial mechanisms underlining acidosis and the potential to recover the process. In this study, triplicate mesophilic anaerobic reactors of 100 L were exposed to acidosis resulting from an exce...

Dairy Manure Anaerobic Digesters

Methanogenic population dynamics during start-up of anaerobic digesters treating municipal solid waste and biosolids.

An aggressive start-up strategy was used to initiate codigestion in two anaerobic, continuously mixed bench-top reactors at mesophilic (37 degrees C) and thermophilic (55 degrees C) conditions. The digesters were inoculated with mesophilic anaerobic sewage sludge and cattle manure and were fed a mixture of simulated municipal solid waste and biosolids in proportions that reflect U.S. production...

Study of Struvite Precipitation in Anaerobic Digesters

-In this paper struvite formation and crystal forms in anaerobic digesters under differing feed types and support media have been studied. Struvite appears when the medium contains magnesium, ammonium and phosphate ions. NH + can be supplied from protein degradation, phosphate from bacterial exudation and Mg 2+ by the supports. The precipitation of struvite has also been checked with real feedi...

Hydrodynamics Study of Sludge in Anaerobic Digesters

Inadequate design and improper mixing operation in anaerobic digesters often lead to poor mixing and digester failures due to the presence of dead zones formed in the digester. More research is required to understand the mixing phenomena in anaerobic digesters and thus improve their efficiency. This paper investigates the efficiency of mixing of digester sludge in a mechanically agitated vessel...