Shortage of potable water is a problem that affects many nations in the world and it will
aggravate in a near future if pertinent actions are not carried out. Decrease in
consumption, improvements in water distribution systems to avoid losses and more
efficient water treatment processes are some actions that can be implemented to attack
this problem. Membrane technology and biological processes are used in wastewater
treatment to achieve high water quality standards. Some other technologies, besides
water treatment, attempt to obtain energy from organic wastes present in water.
In this study, a proof-of-concept was accomplished demonstrating that a Microbial
Electrolysis Cell can be fully integrated with a Membrane Bioreactor to achieve
wastewater treatment and harvest energy. Conductive hollow fiber membranes made
of nickel functioned as both filter material for treated water reclamation and as a
cathode to catalyze hydrogen production reaction. The produced hydrogen was
subsequently converted into methane by hydrogenotrophic methanogens. Organic
removal was 98.9% irrespective of operation mode. Maximum volumetric hydrogen
production rate was 0.2 m3/m3d, while maximum current density achieved was 6.1 A/m2
(based on cathode surface area). Biofouling, an unavoidable phenomenon in traditional
MBRs, can be minimized in this system through self-cleaning approach of hybrid
membranes by hydrogen production. The increased rate of hydrogen evolution at high
applied voltage (0.9 V) reduces the membrane fouling. Improvements can be done in
the system to make it as a promising net energy positive technology for the low strength
wastewater treatment.
Date of Award | Nov 2013 |
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Original language | English (US) |
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Awarding Institution | - Biological, Environmental Sciences and Engineering
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Supervisor | Pascal Saikaly (Supervisor) |
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- Wastewater Treatment
- Membrane Bioreactor
- Biofuels
- Hybrid
- Microbial Electrolysis Cell
- Nickel