title: [Effects of organic loading rate on the cultivation and characteristic of granular sludge with phosphorus removal].
abstract: In an anaerobic/aerobic sequencing batch reactor (SBR), the effect of organic loading rate (OLR) on the formation and phosphorus removal efficiency of granular sludge was investigated under the condition of 1.0-2.0 mg/L of dissolved oxygen (DO) concentration in the period of aerobic feast time in an SBR-cycle. Experiment results showed that the sludge in the SBR was the mixture of a majority of activated sludge floc and a small quantity of round-shaped granular at the OLR of 0.482-0.986 kg/(m3 x d). Granulation was accelerated at the early time of the OLR of 2.218-2.263 kg/(m3 x d), while the morphology of granules changed to an irregular shape on the end of the OLR of 2.218-2.263 kg/(m x d). Then the OLR decreased to 1.113-1.182 kg/(m3 x d), the mature granules were cultivated successfully. The morphology of the mature granules was nearly spherical with a very clear outline. The dimension of granules was 1-2 mm, and the granular sludge had a good settle ability [sludge volume index (SVI) between 20-22 mL/g]. The OLR also had influence on efficiency of phosphorus removal, when the OLR was elevated to 2.218-2.263 kg/(m3 x d), the efficiency of phosphorus removal declined from 99% to 78%, and could not be recovered even if the OLR was decreased to 1.113-1.182 kg/(m3 x d).
authors.affiliation: School of Environmental Science and Engineering, Chang'an University, Xi'an 710064, China. zhangxiaoling101@126.com
authors.forename: Xiao-Ling
authors.initials: XL
authors.lastname: Zhang
authors.forename: Shan
authors.initials: S
authors.lastname: Liu
authors.forename: Xu
authors.initials: X
authors.lastname: Chen
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D001420:Bacteria, Aerobic / Q000378:metabolism; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology; D009930:Organic Chemicals / Q000302:isolation & purification / Q000378:metabolism; D010758:Phosphorus / Q000302:isolation & purification* / Q000378:metabolism; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D009930:Organic Chemicals; D012722:Sewage; D014874:Water Pollutants, Chemical; D010758:Phosphorus