Physico-chemical and microbial characterization of compartment-wise profiles in an anammox baffled reactor

Sherif Ismail; Mohamed Elsamadony; Ahmed Elreedy; Manabu Fujii; Ahmed Tawfik

doi:10.1016/j.jenvman.2018.11.134

Physico-chemical and microbial characterization of compartment-wise profiles in an anammox baffled reactor

J Environ Manage. 2019 Feb 15:232:875-886. doi: 10.1016/j.jenvman.2018.11.134. Epub 2018 Dec 6.

Authors

Sherif Ismail¹, Mohamed Elsamadony², Ahmed Elreedy³, Manabu Fujii⁴, Ahmed Tawfik⁵

Affiliations

¹ Egypt-Japan University of Science and Technology (E-JUST), Environmental Engineering Department, P.O. Box 179, New Borg Al Arab City, Alexandria, 21934, Egypt; Tokyo Institute of Technology, Civil and Environmental Engineering Department, Meguro-ku, Tokyo, 152-8552, Japan; Zagazig University, Environmental Engineering Department, Zagazig, 44519, Egypt. Electronic address: sherif.ismail@ejust.edu.eg.
² Tanta University, Faculty of Engineering, Public Works Engineering Department, 31521, Tanta City, Egypt. Electronic address: mohamed.elsamadony@f-eng.tanta.edu.eg.
³ Tokyo Institute of Technology, Civil and Environmental Engineering Department, Meguro-ku, Tokyo, 152-8552, Japan; Alexandria University, Faculty of Engineering, Sanitary Engineering Department, Alexandria, 21544, Egypt. Electronic address: elreedy.a.aa@m.titech.ac.jp.
⁴ Tokyo Institute of Technology, Civil and Environmental Engineering Department, Meguro-ku, Tokyo, 152-8552, Japan. Electronic address: fujii.m.ah@m.titech.ac.jp.
⁵ National Research Centre, Water Pollution Research Department, Giza, 12622, Egypt. Electronic address: tawfik8@hotmail.com.

PMID: 30530278
DOI: 10.1016/j.jenvman.2018.11.134

Abstract

In this study, compartment-wise investigation of an anammox baffled reactor (AnBR) was performed. The AnBR achieved steady-state conditions after a start-up period of ∼50 days and achieved NH₄ and NO₂ conversion percentages of 88.5 and 99.3%, respectively. Examination of the nitrogen mass balance revealed that an AnBR with a two-compartment configuration was sufficient for nitrogen loading rates (NLRs) ranging from 0.125 to 1.975 kg N/m³/d and resulted in a nitrogen removal efficiency (NRE) of 86.7-93.7%. Higher NLRs (4.04-5.05 kg N/m³/d) required four compartments to achieve an NRE of 82.2-87.1%. Further, an overall NLR increase of up to 5.93 ± 0.23 kg N/m³/d resulted in complete AnBR failure. The maximum nitrogen removal rate was consistently recorded in the 1^st compartment for all NLRs examined; as a result, this compartment exhibited the highest bacterial activity. Biomass concentration, specific anammox activity, extracellular polymeric substances, and average granule diameter in the 1^st compartment with an overall NLR of 0.05 kg N/m³/d were estimated to be 11.2 g_VSS/L, 0.03 mg N/g_VSS/h, 84.3 mg/g_VSS, and 0.65 mm, respectively. These values increased to 26.1 g_VSS/L, 11.80 mg N/g_VSS/h, 242.1 mg/g_VSS, and 2.31 mm, respectively, when the overall NLR was incremented to 4.04 kg N/m³/d. However, a gradual reduction in bacterial activity was observed from the 1^st to the 5^th compartment. The microbial community analysis indicated that the dominant phyla in the 1^st compartment (NLR of 0.252 kg N/m³/d) with the highest nitrogen removal were Chloroflexi (38.13%), Planctomycetes (22.62%), and Proteobacteria (14.75%).

Keywords: Anammox baffled reactor; Compartment-wise profile; Microbial analysis; Sludge characteristics.

MeSH terms

Bacteria
Biomass
Bioreactors*
Nitrogen
Oxidation-Reduction
Sewage*

Substances

Sewage
Nitrogen