Energy positive domestic wastewater treatment: the roles of anaerobic and phototrophic technologies


Shoener, B. D.
Bradley, I. M.
Cusick, R. D.
Guest, J. S.

KAUST Grant Number
UIeRA 2012-06291


The negative energy balance of wastewater treatment could be reversed if anaerobic technologies were implemented for organic carbon oxidation and phototrophic technologies were utilized for nutrient recovery. To characterize the potential for energy positive wastewater treatment by anaerobic and phototrophic biotechnologies we performed a comprehensive literature review and analysis, focusing on energy production (as kJ per capita per day and as kJ m-3 of wastewater treated), energy consumption, and treatment efficacy. Anaerobic technologies included in this review were the anaerobic baffled reactor (ABR), anaerobic membrane bioreactor (AnMBR), anaerobic fluidized bed reactor (AFB), upflow anaerobic sludge blanket (UASB), anaerobic sequencing batch reactor (ASBR), microbial electrolysis cell (MEC), and microbial fuel cell (MFC). Phototrophic technologies included were the high rate algal pond (HRAP), photobioreactor (PBR), stirred tank reactor, waste stabilization pond (WSP), and algal turf scrubber (ATS). Average energy recovery efficiencies for anaerobic technologies ranged from 1.6% (MFC) to 47.5% (ABR). When including typical percent chemical oxygen demand (COD) removals by each technology, this range would equate to roughly 40-1200 kJ per capita per day or 110-3300 kJ m-3 of treated wastewater. The average bioenergy feedstock production by phototrophic technologies ranged from 1200-4700 kJ per capita per day or 3400-13000 kJ m-3 (exceeding anaerobic technologies and, at times, the energetic content of the influent organic carbon), with usable energy production dependent upon downstream conversion to fuels. Energy consumption analysis showed that energy positive anaerobic wastewater treatment by emerging technologies would require significant reductions of parasitic losses from mechanical mixing and gas sparging. Technology targets and critical barriers for energy-producing technologies are identified, and the role of integrated anaerobic and phototrophic bioprocesses in energy positive wastewater management is discussed. © 2014 the Partner Organisations.

Shoener BD, Bradley IM, Cusick RD, Guest JS (2014) Energy positive domestic wastewater treatment: the roles of anaerobic and phototrophic technologies. Environmental Science: Processes & Impacts 16: 1204. Available:

This work was partially funded by the King Abdullah University of Science and Technology (KAUST) Academic Partnership Program (UIeRA 2012-06291), and by the Center of Advanced Materials for the Purification of Water with Systems (Water-CAMPWS) under NSF Agreement Number CTS-0120978. The authors would like to acknowledge the Jack Kent Cooke Foundation for partial funding for B. D. Shoener, and the Safe Global Water Institute (SGWI) at the University of Illinois at Urbana-Champaign (UIUC) for partial funding for I. M. Bradley. We would also like to thank Cheng Zhong (UIUC) and Anthony Greiner (Hazen and Sawyer) for their assistance in energy consumption estimation, Shijie (Moses) Leow (UIUC) for discussions on hydrothermal liquefaction, and the anonymous reviewers for their constructive comments that strengthened the manuscript.

Royal Society of Chemistry (RSC)

Environmental Science: Processes & Impacts


PubMed ID

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