The morphological and settling properties of ANAMMOX granular sludge in high-rate reactors

Hui-feng Lu; Qi-xing Ji; Shuang Ding; Ping Zheng

doi:10.1016/j.biortech.2013.06.046

The morphological and settling properties of ANAMMOX granular sludge in high-rate reactors

Bioresour Technol. 2013 Sep:143:592-7. doi: 10.1016/j.biortech.2013.06.046. Epub 2013 Jun 22.

Authors

Hui-feng Lu¹, Qi-xing Ji, Shuang Ding, Ping Zheng

Affiliation

¹ Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.

PMID: 23835264
DOI: 10.1016/j.biortech.2013.06.046

Abstract

Digital macro photography and settling tests were carried out to investigate the morphological and settling characteristics of ANAMMOX granules in a high-rate reactor. The ANAMMOX granules could be divided into settling and floating granules. The settling granules with an average diameter of 2.96±0.99 mm were smaller than the floating granules with an average diameter of 4.58±1.22 mm. A settling model was established and validated to correlate the settling velocity with the density (ρG), mass shape factor (ψmass), shape-correction factor (characterized by sphericity (Φ(')) or roundness (ξ)) and projected area equivalent sphere diameter (dP) of ANAMMOX granules. The sphericity was more suitable than the roundness for describing the settling behavior. The sensitivity of four parameters was in the order of ρG,ψmass, dP and Φ('). Based on the settling model, ANAMMOX granules with diameter of 1.75-4.00 mm were supposed to be optimal for the ANAMMOX process.

Keywords: ANAMMOX granular sludge; Morphology; Settleability; Settling model.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Ammonia / metabolism*
Anaerobiosis
Bioreactors*
Models, Theoretical
Oxidation-Reduction
Sewage*

Substances

Sewage
Ammonia