Maximisation of the organic load rate and minimisation of oxygen consumption in aerobic biological wastewater treatment processes by manipulation of the hydraulic and solids residence time

Davide Dionisi (Corresponding Author), Adamu Abubakar Rasheed

Research output: Contribution to journalArticle

5 Citations (Scopus)
5 Downloads (Pure)

Abstract

A systematic experimental study of the effect of hydraulic residence time (HRT) and solids residence time (SRT) on conventional suspended-growth biological wastewater treatment processes was carried out. The aim of this study was to identify the conditions that minimise the reactor volume, i.e. maximise the organic load rate (OLR), and minimise the oxygen consumption. Lab-scale sequencing batch reactors (SBRs) were operated with glucose or ethanol as only carbon sources, with HRT in the range 0.25-4 day and SRT in the range 1-71 day. The highest OLR values which gave satisfactory performance were 4.28 and 4.14 gCOD/l.day for glucose and ethanol, respectively, which are among the highest reported for conventional aerobic suspended-growth processes. The highest OLR values were obtained with HRT=0.25 day, SRT=3.1 day for glucose and HRT=0.5 day, SRT=4.9 day for ethanol. The minimum oxygen consumption was 0.36 and 0.69 kg O2/kg COD removed for glucose and ethanol, respectively. In disagreement with conventional theories, it was found that biomass production also depended on the OLR as well as on the SRT, higher OLRs giving lower biomass production for the same SRT. From the kinetic analysis of the experimental data, this behaviour, which has important consequences for the design of biological wastewater treatment processes, was explained with a higher rate of endogenous metabolism at higher OLRs.
Original languageEnglish
Pages (from-to)138-146
Number of pages9
Journal Journal of Water Process Engineering
Volume22
Early online date8 Feb 2018
DOIs
Publication statusPublished - Apr 2018

Fingerprint

Waste Water
oxygen consumption
Oxygen Consumption
Wastewater treatment
residence time
Hydraulics
Oxygen
hydraulics
Glucose
Ethanol
ethanol
glucose
Biomass
Batch reactors
Metabolism
rate
biological wastewater treatment
Carbon
biomass
Growth

Keywords

  • Aerobic wastewater treatment
  • hydraulic residence time (HRT)
  • organic load rate (OLR)
  • solids residence time (SRT)
  • oxygen consumption

Cite this

@article{5137732b222a4f8b8cade18573a27401,
title = "Maximisation of the organic load rate and minimisation of oxygen consumption in aerobic biological wastewater treatment processes by manipulation of the hydraulic and solids residence time",
abstract = "A systematic experimental study of the effect of hydraulic residence time (HRT) and solids residence time (SRT) on conventional suspended-growth biological wastewater treatment processes was carried out. The aim of this study was to identify the conditions that minimise the reactor volume, i.e. maximise the organic load rate (OLR), and minimise the oxygen consumption. Lab-scale sequencing batch reactors (SBRs) were operated with glucose or ethanol as only carbon sources, with HRT in the range 0.25-4 day and SRT in the range 1-71 day. The highest OLR values which gave satisfactory performance were 4.28 and 4.14 gCOD/l.day for glucose and ethanol, respectively, which are among the highest reported for conventional aerobic suspended-growth processes. The highest OLR values were obtained with HRT=0.25 day, SRT=3.1 day for glucose and HRT=0.5 day, SRT=4.9 day for ethanol. The minimum oxygen consumption was 0.36 and 0.69 kg O2/kg COD removed for glucose and ethanol, respectively. In disagreement with conventional theories, it was found that biomass production also depended on the OLR as well as on the SRT, higher OLRs giving lower biomass production for the same SRT. From the kinetic analysis of the experimental data, this behaviour, which has important consequences for the design of biological wastewater treatment processes, was explained with a higher rate of endogenous metabolism at higher OLRs.",
keywords = "Aerobic wastewater treatment, hydraulic residence time (HRT), organic load rate (OLR), solids residence time (SRT) , oxygen consumption",
author = "Davide Dionisi and Rasheed, {Adamu Abubakar}",
note = "The assistance of Ms Liz Hendrie in setting up the experiments is highly acknowledged and appreciated.",
year = "2018",
month = "4",
doi = "10.1016/j.jwpe.2018.02.002",
language = "English",
volume = "22",
pages = "138--146",
journal = "Journal of Water Process Engineering",
issn = "2214-7144",
publisher = "Elsevier",

}

TY - JOUR

T1 - Maximisation of the organic load rate and minimisation of oxygen consumption in aerobic biological wastewater treatment processes by manipulation of the hydraulic and solids residence time

AU - Dionisi, Davide

AU - Rasheed, Adamu Abubakar

N1 - The assistance of Ms Liz Hendrie in setting up the experiments is highly acknowledged and appreciated.

PY - 2018/4

Y1 - 2018/4

N2 - A systematic experimental study of the effect of hydraulic residence time (HRT) and solids residence time (SRT) on conventional suspended-growth biological wastewater treatment processes was carried out. The aim of this study was to identify the conditions that minimise the reactor volume, i.e. maximise the organic load rate (OLR), and minimise the oxygen consumption. Lab-scale sequencing batch reactors (SBRs) were operated with glucose or ethanol as only carbon sources, with HRT in the range 0.25-4 day and SRT in the range 1-71 day. The highest OLR values which gave satisfactory performance were 4.28 and 4.14 gCOD/l.day for glucose and ethanol, respectively, which are among the highest reported for conventional aerobic suspended-growth processes. The highest OLR values were obtained with HRT=0.25 day, SRT=3.1 day for glucose and HRT=0.5 day, SRT=4.9 day for ethanol. The minimum oxygen consumption was 0.36 and 0.69 kg O2/kg COD removed for glucose and ethanol, respectively. In disagreement with conventional theories, it was found that biomass production also depended on the OLR as well as on the SRT, higher OLRs giving lower biomass production for the same SRT. From the kinetic analysis of the experimental data, this behaviour, which has important consequences for the design of biological wastewater treatment processes, was explained with a higher rate of endogenous metabolism at higher OLRs.

AB - A systematic experimental study of the effect of hydraulic residence time (HRT) and solids residence time (SRT) on conventional suspended-growth biological wastewater treatment processes was carried out. The aim of this study was to identify the conditions that minimise the reactor volume, i.e. maximise the organic load rate (OLR), and minimise the oxygen consumption. Lab-scale sequencing batch reactors (SBRs) were operated with glucose or ethanol as only carbon sources, with HRT in the range 0.25-4 day and SRT in the range 1-71 day. The highest OLR values which gave satisfactory performance were 4.28 and 4.14 gCOD/l.day for glucose and ethanol, respectively, which are among the highest reported for conventional aerobic suspended-growth processes. The highest OLR values were obtained with HRT=0.25 day, SRT=3.1 day for glucose and HRT=0.5 day, SRT=4.9 day for ethanol. The minimum oxygen consumption was 0.36 and 0.69 kg O2/kg COD removed for glucose and ethanol, respectively. In disagreement with conventional theories, it was found that biomass production also depended on the OLR as well as on the SRT, higher OLRs giving lower biomass production for the same SRT. From the kinetic analysis of the experimental data, this behaviour, which has important consequences for the design of biological wastewater treatment processes, was explained with a higher rate of endogenous metabolism at higher OLRs.

KW - Aerobic wastewater treatment

KW - hydraulic residence time (HRT)

KW - organic load rate (OLR)

KW - solids residence time (SRT)

KW - oxygen consumption

U2 - 10.1016/j.jwpe.2018.02.002

DO - 10.1016/j.jwpe.2018.02.002

M3 - Article

VL - 22

SP - 138

EP - 146

JO - Journal of Water Process Engineering

JF - Journal of Water Process Engineering

SN - 2214-7144

ER -