Comparative Study On Organic Wastewater Treatment Between Anaerobic Continuous Flow And Anaerobic Sequencing Batch Reactor

This experiment contrastively studied anaerobic continuous flow reactor andanaerobic sequencing batch reactor （ASBR） by glucose-fed in order to research the twotypes of metabolic mode of anaerobic digestion reactors.The experimental results show that glycogen storage phenomenon exists inanaerobic sequencing batch reactor. In this way, the phenomenon slows down theaccumulation of the volatile fatty acids （VFA） and reduces the hydrogen pressurewithin the reactor, creating favorable conditions for the smooth metabolism of aceticacid bacteria and methanogen. Thus it maintains the ecological balance of theanaerobic system and makes sure the smooth process of methane. However, incontinuous flow reactor, there is no glycogen storage phenomenon. The glucosedirectly degraded into VFA, and therefore affects the normal operation in the reaction.In the first stage, the maximum utilization rate of hydrogen of activated sludge inanaerobic continuous flow reactor is22.2mL-H₂/gVSS·h, and16.05mL-H₂/gVSS·h inanaerobic sequencing batch reactor. In the second stage, the maximum utilization rateof hydrogen in the anaerobic continuous flow reactor is30.84mL-H₂/gVSS·h, and22.09mL-H₂/gVSS·h in anaerobic sequencing batch reactor. From the experimentalresults we can see that the hydrogen utilization rate of unit quality activated sludge inanaerobic continuous flow reactor is greater than in sequencing batch reactor.During the first reaction stage in the research, the specific methanogenic activityof ethanol, acetic acid, propionic acid and butyric acid in anaerobic continuous flowreactor and ASBR are2.8969gCOD-CH₄/gVSS·d and0.7822gCOD-CH₄/gVSS·d,1.8043gCOD-CH₄/gVSS·d、0.5133gCOD-CH₄/gVSS·d,1.2215gCOD-CH₄/gVSS·d、 0.5182gCOD-CH₄/gVSS·d,0.8963gCOD-CH₄/gVSS·d、0.1524gCOD-CH₄/gVSS·d; Inthe second stage, the specific methanogenic activity of ethanol in anaerobic continuousflow reactor and anaerobic sequencing batch reactor are2.8796gCOD-CH₄/gVSS·d、1.0686gCOD-CH₄/gVSS·d, the activity of acetic acid are1.5834gCOD-CH₄/gVSS·dand0.5909gCOD-CH₄/gVSS·d, the activity of propionic acid are0.8220gCOD-CH₄/gVSS·d and0.6846gCOD-CH₄/gVSS·d, the activity of butyric acid are0.8897gCOD-CH₄/gVSS·d and0.1558gCOD-CH₄/gVSS·d. We can see that the specificmethanogenic activity of ethanol, acetic acid, propionic acid and butyric acid inanaerobic continuous flow reactor are higher than those in anaerobic sequencing batchreactor. In addition, the fermentation type in continuous flow reactor and anaerobicsequencing batch reactor are all propionic type fermentation.According to the microscopic examination, we can see the activated sludge incontinuous flow reactor presents floc shape, and we can obviously see a lot offilamentous bacteria. Meanwhile, in ASBR, the flocs of activated sludge distributesclosely, and there is an obvious dividing line without any filamentous bacteria.Granular sludge is not found in both two reactors.