title: [Stability control of aerobic granules using an innovative reactor].
abstract: Uncontrolled variation of diameter and density of aerobic granules frequently resulted in instability and thus brought about operation failure. An innovative reactor was therefore developed for the control of diameter and density of aerobic granules. There were two ways to select the sludge, one was the short settling time select the big and dense granules in the reactor, and the other was the hydro cyclone that washed out the big and compact granules preventing big and compact fourthly growth in the reactor. By these means, the diameter of granules could maintained in the range of 300-1 000 microm for a long time, consequently, the long term stability could be obtained. According to the kinetic analysis, it was found that the energy maintenance coefficient was 0.08-0.10, which was much higher than the conventional granular system (0.06), and the ratio of the COD used for maintenance to the influent was higher than the conventional one. Additionally, the removal efficiencies of COD and ammonia were 92% and 60%, respectively.
authors.affiliation: Key Laboratory of Northwest Water Resources, Environment and Ecology, Ministry of Education, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China. lizhihua@gmail.com
authors.forename: Zhi-Hua
authors.initials: ZH
authors.lastname: Li
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
authors.forename: Sheng
authors.initials: S
authors.lastname: Li
authors.forename: Lei
authors.initials: L
authors.lastname: Xie
authors.forename: Xiao-Chang
authors.initials: XC
authors.lastname: Wang
mesh_terms: D000332:Aerobiosis; D000641:Ammonia / Q000302:isolation & purification; D057919:Biological Oxygen Demand Analysis / Q000706:statistics & numerical data; D019149:Bioreactors; D010316:Particle Size; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D012722:Sewage; D000641:Ammonia