Study On Rapid Cultivation Of Aerobic Granular Sludge And Treatment Of Landfill Leachate

Aerobic granule sludge is a novel environmental biotechnological process. Compare with the activated sludge, the aerobic granule has better performance on settling, higher biomass concentration and compact microbial structure. Recently, it has been taken a lot of attention of the scholars at home and abroad. Although the sludge has so many advantages, but the aerobic granule sludge technology has been no large-scale application so far because of the more difficult actual engineering training, the higher operating costs and the instability of granule. For the above reasons, the study had mainly discussed that:(1) rapid cultivation of aerobic granule sludge;(2) study the treatment of landfill leachate with the aerobic granule sludge and optimize operation pamameters of the aerobic granule system.In this experiment, the SBR reactors R1, R2and R3had been inoculated with the activated sludge, then the crushed aerobic granule sludge and granular activated carbon had been added to R2and R3respectively, kept the total MLVSS equal. After, began to evaluated the the speed of granular sludge cultivation in each reactor; stutied on treatment of the landfill leachate with early cultivation aerobic granule sludge, and found cost-effective operation pamameters about the system. The results showed that:(1) Adding the20%total MLVSS crushed aerobic granule sludge and granular activated carbon to the reactor could reduce cultivation time of aerobic granular sludge. In R1, R2and R3, aerobic granular sludge matured at35d,20d and30d respectively. After20days, aerobic granular sludge was cultivated successful in R2, the diameter of aerobic granule was approximately1mm, the proportion of the aerobic granule was1.024g/cm3, the average setting velocity reached57.48m/h and the complete coefficient was97.86%; In R2the removal efficiency of TN and TP reached97.31%and67.69%.(2) The protein content (PN) of R1, R2and R3gradually increased, especially the PN value in R2was higher than R1’s and R3’s. The reason for the faster granular formation speed in R2was that the PN of crushing granular sludge added in is43.72mg/gVSS, the higher PN could promote the sludge to agglomerate, reduce cultivation time of aerobic granular sludge。(3) After the period of the32days’acclimation, the aerobic granular sludge had adapted to landfill leachate step by step, the removal efficiency of COD, NH4+N and TN was85.73%,98.92%,75.70%eventually.(4) After investigating the influence of operating period, aeration rate, and anoxic time, the result showed that when the operating cycle was4h, it just reduced the starvation period to1h and the granular sludge became more stable, the removal efficiency improved; when the aeration rate was about160L/h, the removal efficiency of TN with treatment of granular sludge was76.12%, the property of granular sludge was favorable. When keeping the anoxic time for20min, the intensity of granular sludge, the density and the average speed of settlement was96.54%,1.033g/cm3and50.68m/h respectively.