The integrated biorefinery is emerging, sustainable, energy producing wastewater treatment, which can also provide a renewable source of various useful products, such as biohydrogen, bioelectricity, nutrients and other biobased products. Bioelectrochemical systems (BESs) have the potential to become indispensable in biorefineries due to different options they provide in manipulating the systems and its components thereby optimizing the factors governing the performance of the system. They can be defined as emerging bioconversion technologies to produce energy from wastewaters, which are comprehensively studied only since the last decade. BESs use microbes to consume biodegradable substrates and convert the chemical energy to direct electrical current or gaseous fuels like hydrogen and methane. It is even more advantageous than highly acclaimed anaerobic digestion (AD) as it does not require high strength wastewater and high temperature. Like an electrochemical cell, it consists of an anode (for oxidation) and a cathode (for reduction) often with a membrane in between.
BES can be used as a (i) microbial fuel cell (MFC) when the system produces electrical energy or (ii) as a microbial electrolysis cell (MEC) when it utilises electrical energy to promote electrochemical reactions, that are thermodynamically unfavourable. Anodic reactions are quite akin in both MFCs and MECs, and any organic matter including complex wastewater can act as a suitable fuel for BESs. The primary difference, however, lies on the cathode side. In MFCs, electrical current flows immediately due to the presence of an oxidative agent but MECs require a minimum electrical energy to complete the redox reaction and to produce valuable products (such as hydrogen, methane and nutrients). The direct conversion of chemical to electrical energy in MFCs not only reduces carbon footprint, but also provides operational flexibility. Both MFCs and MECs are extensively studied in treatment of wastewaters.
Several studies have thus been reported concerning BESs usage, however, there is not much systematic and detailed work reported dealing with the combination of AD and BES. This study is likely to greatly help the scientific community to use this combination as an approach to recover ammonium and enriched biogas, improve the treated effluent quality and system stability, as well as optimise energy recovery. The data generated in this work can also be applied in various high polluting industries such as oil refineries, electro-plating industries, chemicals, etc.
Requirements from Students
a) Background in Chemical Engineering/Environmental Engineering/Biotechnology
b) Knowledge of membrane and electrochemistry would be added advantage
a) Optimization of energy production from an integrated AD-BES system
b) Preparation of two-chambered cells with cation exchange membrane
c) Estimating optimized COD removal
d) Studying the performance and robustness of the integrated systems in series, with operation against the shock loading (VFA, organic and nitrogen shocks)
e) Biogas upgrading by utilizing MEC with a biocathode as a post-treatment to AD.
f) Effect of pre-acclimation to domestic wastewater for improve methane production and treatability
g) Influence of biocathode hydraulic retention time (HRT) on methane production rate
The Materials and Engineering Research Institute (MERI) is a dynamic interdisciplinary research institute dedicated to addressing industrial problems through the application of fundamental science and engineering. For information about MERI please visit https://www.shu.ac.uk/research/specialisms/materials-and-engineering-research-institute
Application deadline: applicants accepted all year round with enrolments during September, February (January on website) and May
Duration: 4 years full time, 7 years part time.