Microbial Storage And Hydrogen Partial Pressure Regulation In Anaerobic Biological Treatment

This study demonstrates the glycogen storage and hydrogen partial pressure regulation in a glucose-fed anaerobic sequencing batch reactor (ASBR) and a glucose-fed anaerobic continuous flow reactor.The experiment results indicate that the fermentation bacteria accumulated glucose as glycogen when the substrate was adequate in a glucose-fed anaerobic sequencing methane fermentation system. When the substrate was deficient, the fermentation bacteria would ferment the stored glycogen. Glycogen storage slowed down the accumulation of VFA and the producing of hydrogen, therefore reduced the hydrogen partial pressure of the reactor. Glycogen storage was closely related to F/M. The bigger F/M ratio was fed, the more glycogen was stored. The more glycogen was stored, the lower partial hydrogen pressure appearing in the reactor. When the F/M were 0.108 and 0.145, the maximum storage capacities could reach as high as 48.43mg/g,67.20mg/gVSS, accounted for 42%-44% of COD-fed, the corresponding hydrogen partial pressure were 28.3Pa and 5.4Pa.When in a glucose-fed anaerobic continuous methane fermentation reactor, with the same organic loading rate, glucose was utilized by fermentation bacteria continuously. As a result, there has not extra substrate to store. The corresponding hydrogen partial pressure was approximately 288.1Pa.Sludge morphology was observed by optical microscope. Sludge in ASBR was loose and flocculent. There was no filamentous. The sedimentation of sludge was good in ASBR, SVI was 31-45mL/g. In contrast, there was mass of filamentous bacteria in continuous flow reactor. The settling of sludge has gone bad, SVI was 125-134mL/g, much sludge effused from reactor.The maximum specific methanogenic activity for format, acetate, propionate and butyrate were 0.1796,0.5215,0.2328,0.4935 gCOD-CH4/gVSS·d in ASBR and 0.3001,0.5446,0.3779,0.2890 gCOD-CH4/gVSS·d in continuous flow reactor.