Glycogen Storage In Anaerobic Sequencing Batch Reactor (ASBR)

In this paper,sludge characteristics and glycogen storage in anaerobic sequencing batch reactors fed with glucose were investigated.When COD in the influent was 7000 mg/L,HRT was controlled in 1 day,the ratio of remove could reach as high as 85%,pH were between 6.8 and 7.5.The sludge formed in the reactor was of floc structure,MLVSS/MLSS was 82%-92%,SV was 55%-65%,SVI was 35-60mL/g.When the sludge loading rate was 1.02gCOD/gVSS·d,the maximum specific methanogenic activity for formate, acetate,propionate and butyrate were 0.31,0.88,0.58 and 0.78gCOD-CH₄/gVSS·d. When sludge loading was 1.22gCOD/gVSS·d,the maximum specific methanogenic activity for formate,acetate,propionate and butyrate increased to 0.45,1.18,0.98 and 0.85 gCOD-CH₄/gVSS·d.There are three ways for utilizing carbohydrate in ASBR:degradation, biosynthesis,storage.Storage is the main reaction process during the feeding stage (accounted for 34%-37%of COD-fed).VFA production rate slows down due to glucose storage,which results in low VFA accumulation and granttees a stable operation in ASBR under high loading rate.When the F/M were 0.21,0.31 and 0.46,the maximum storage capacities could reach as high as 84.53,115.43,158.32 mgCOD/gVSS.The bacterial accumulation capacities increased with F/M.Nutrient deficiency had great influence to glycogen storage.The storage accounted for 24-27%of COD-fed under nutritient adequate,but the ratio was as high as 30%-50%under nutrient deficiency.When COD-fed was 7000mg/L, ammonia nitrogen concentration was kept 1400mg/L,phosphorus concentration was reduced from 23 mg/L to 0,the storage increased from 57.07 mgCOD/gVSS to 99.97mgCOD/gVSS.Phosphorus concentration was kept 23 mg/L,ammonia nitrogen concentration was reduced to 0,the storage increased to 119.28mgCOD/gVSS.When the concentration of ammonia nitrogen and phosphorus were reduced to 0,the storage was increased to 85.81 mgCOD/gVSS.The storage quantity was more higher in nutrient deficiency condition,this can provide theoretical basis for nutrient deficiency wastewater.There was no substrate,the rate of glycogen degradation dropped sharply in first two hours,it could reach 19.09mgCOD/gVSS·h.But the drop was slow in last two hours,and the minimum rate was 2.65mgCOD/gVSS·h.