Study On Characteristics Of Activated Sludge Mixture In A/ombr Process

The subject explains the effects of sludge load, aeration intensity and reflux ratio do to the activated sludge in the aerobic bank of A/OMBR,so to understand deeply the interaction between the chemical and physical properties of the sludge mixture.The test includes two parts, runs four months time. The first part is about the effects that the sludge load does to the mixture of membrane bioreactor,the experiments relies on a Tianjin MBR Demonstration Project. The second part mainly be upon the pilot reactor, explores the effects that aeration strength and backflow ratio do to the mixture. With the original water fluctuation, sludge load and the EPS of the mixture changes, experiment shows that the sludge sedimentation, sludge viscosity are significantly related to EPS. The sludge load has remarkable correlation with the membrane bioreactor mixture characteristics. When the sludge load is lower than 0.14kgCOD/(kgMLSS·d),the competition between microbes in the state of the poor nutrition is fiercer. So the microbes will absorb for more organic matter in its surface, if this situation is worse,the sludge load lower than 0.10kgCOD/(kgMLSS·d), because of microorganisms, EPS will increase. On the other hands, high aeration strength will flute the active sludge more finely, stimulate microbes produce more EPS, By increasing the reflux ratio, the particle size of the activity sludge will be recovered on a certain degree, but EPS increases. That is mainly because that the way of backflow that makes the particle size recover mainly depends absorbing more organisms. Then the more EPS, the higher viscosity and SVI, and the research shows that in a certain range as EPS increases, the active sludge increases.Through the experiment research, we have more deeply understanding on the parameters that effect the characteristics of the mixture in A/OMBR process, so provide certain reference on engineering.