1st Edition
Optimization of the Electron Donor Supply to Sulphate Reducing Bioreactors Treating Inorganic Wastewater
The main objective of this research was to optimize the electron donor supply in sulphate reducing bioreactors treating sulphate rich wastewater. Two types of electron donor were tested: lactate and slow release electron donors such as carbohydrate based polymers and lignocellulosic biowastes. Biological sulphate reduction was evaluated in different bioreactor configurations: the inverse fluidized bed, sequencing batch and batch reactors. The reactors were tested under steady-state, high-rate and transient-state feeding conditions of electron donor and acceptor, respectively. The results showed that the inverse fluidized bed reactor configuration is robust and resilient to transient and high-rate feeding conditions at a hydraulic retention time as low as 0.125 d. The biological sulphate reduction was limited by the COD:sulphate ratio (< 1.7). The results from artificial neural network modelling showed that the influent sulphate concentrations synergistically affected the COD removal efficiency and the sulphide production. Concerning the role of electron donors, the slow release electron donors allowed a biological sulphate reduction > 82% either using carbohydrate based polymers or lignocellulosic bio-wastes, in batch bioreactors. The biological sulphate reduction was limited by the hydrolysis-fermentation rate and by the complexity of the slow release electron donors.
Chapter 1 - Introduction
1.1 Background
1.2 The PhD thesis structure
1.3 References
Chapter 2 - Literature review
Abstract
2.1 Anaerobic digestion
2.2 The sulphate reduction process
2.3 Electron donors for SRB
2.4 Conventional bioreactors for sulphate reduction
2.5 Modelling biological sulphate reduction
2.6 Conclusions
2.7 References
Chapter 3 - Forecasting the effect on feast and famine conditions on biological sulphate reduction in an anaerobic inverse fluidized bed reactor using artificial neural networks
Abstract
3.1 Introduction
3.2 Material and methods
3.3 Results
3.4 Discussion
3.5 Conclusions
3.6 References
Chapter 4 - High rate biological sulphate reduction in a lactate fed inverse fluidized bed reactor at a hydraulic retention time of 3 H
Abstract
4.1 Introduction
4.2 Material and methods
4.3 Results
4.4 Discussion
4.5 Conclusions
4.6 References
Chapter 5 - Effect of the initial sulphate concentration on the start-up phase of the biological sulphate reduction in sequencing batch reactors
Abstract
5.1 Introduction
5.2 Material and methods
5.3 Results
5.4 Discussion
5.5 Conclusions
5.6 References
Chapter 6 - The effect of nitrogen and electron donor feastfamine conditions on biological sulphate reduction in inorganic wastewater treatment
Abstract
6.1 Introduction
6.2 Material and methods
6.3 Results
6.4 Discussion
6.5 Conclusions
6.6 References
Chapter 7 - The effect of feast and famie conditions on biological sulphate reduction in anaerobic sequencing batch reactors
Abstract
7.1 Introduction
7.2 Material and methods
7.3 Results
7.4 Discussion
7.5 Conclusions
7.6 References
Chapter 8 - Carbohydrate based polymeric materials as slow release electron donors for sulphate removal from wastewater
Abstract
8.1 Introduction
8.2 Material and methods
8.3 Results
8.4 Discussion
8.5 Conclusions
8.6 References
Chapter 9 - Lignocellulosic biowastes as carrier material and slow release electron donor for sulphidogenesis of wastewater in an inverse fluidized bed bioreactor
Abstract
9.1 Introduction
9.2 Material and methods
9.3 Results
9.4 Discussion
9.5 Conclusions
9.6 References
Chapter 10 - General discussion and perspectives
10.1 Introduction
10.2 General discussion and conclusions
10.3 Future research work
10.4 References
Biography
Luis Carlos Reyes-Alvarado (born in Córdoba, Veracruz, Mexico) obtained his PhD in Environmental Technology. He joined the Universidad Veracruzana (Mexico) where he obtained the degree of Chemical Engineering and further a Master in Food Science and Technology, after which he received an ALFA grant within the SUPPORT (Sustainable Use of Photosynthesis Products & Optimum Resource Transformation) project at the TU Graz (Austria).
Luis developed and defended his PhD thesis through the Erasmus Mundus Joint Doctorate Programme in Environmental Technologies for Contaminated Solids, Soils and Sediments (ETeCoS3) on December 16th, 2016. His research was focused on the optimization of electron donor supply to sulphate reducing bioreactors treating inorganic wastewater rich in sulphate and carried out at different institutions: the UNESCO-IHE (Delft, The Netherlands), the Universidad Veracruzana (Veracruz, Mexico), the INRA-Laboratoire de Biotechnologie de l’Environnement (Narbonne, France) and the University of Cassino and Southern Lazio (Cassino, Italy). Luis' main interest is understanding the engineering aspects of biological processes, resource recovery from waste and the development of eco-technologies for waste remediation.
