Delivery of the research objectives will be achieved through work in 5 complementary individual research projects (PhD thesis), each involving collective approach and involvement of both academic and non-academic partners.
To evaluate sustainable and innovative wastewater treatment technologies to improve the removal efficiency of microcontaminants. The proposed technologies will be a combination of biological processes such as membrane biological reactors (MBR) with polishing stages such as advanced oxidation processes (AOP), activated carbon and bioelctrochemical systems (BES) or MBR with bioaugmentation.
So far, several technologies have been evaluated for the removal of emerging pollutants. The partners of this project have experience on several of these technologies. AQUAFIN (together with Ghent University) developed and validated the BioMAC concept which couples an in-situ regenerative biological activated carbon filter followed by a microfiltration unit. UdG have proven the removal efficiency of emerging compounds with advanced treatments, such as integrated membrane systems (MBR+NF/RO) and AOP, individually. It is expected that after evaluating different combinations of technologies the ESR will be able to propose more sustainable solutions for microcontaminants removal. Hence, the ESR will conduct a holistic evaluation in terms of technological (removal efficiencies and most relevant design and operational conditions), costs, and environmental aspects, for the different combinations of technologies, also exploring the potential for water reuse.
Different advanced wastewater treatment processes have proven to render persistent and even toxic intermediates, so disappearance of the parent contaminant does not imply that the treatment was efficient. Considering the potential hazards of by-products generated during treatment, their identification and quantification, as well as elucidation of main reaction mechanisms, are necessary for the safe application of such processes for wastewater treatment. The main objective of this ESR is to elucidate transformation pathways and identify structures of main transformation products (TPs) from selected emerging microcontaminants formed during treatments studied in PhD project 1 (BioMAC, MBR, Bioaugmentation, AOP and BES) and evaluate potential ecotoxicological effects of intermediate TPs. In addition, aim is to get better insight into transformation processes during treatment, such as deconjugation (relevant for hormones and pharmaceuticals) and chiral transformations (pharmaceuticals and their metabolites). The tentative list of target emerging microcontaminants includes those on the watch list of EU WFD (diclofenac, estradiol, ethynilestradiol), other pharmaceuticals identified as having high potential to enter the environment and so far not studied in wastewater treatment processes (levotyroxine, alendronic acid, topiramate, pioglitazone, telmisartan pregabalin and quetiapine). Additionally, other microcontaminants will be considered in a prioritisation exercise performed with the aim to quantify the risk of hazardous compounds using GIS based risk assessment. Acute and chronic toxicity of TPs and mixtures will be determined at the different stages of the treatment using in-vitro assays (Vibrio fisheri, Scenedesmus, Daphnia, and Zebra fish).
The ESR will learn about the identification of main TPs formed during wastewater treatment for selected emerging contaminant and will have deep knowledge on mechanisms governing transformation of contaminants, including deconjugation and chiral transformations. The candidate will become an expert on the potential toxicity of the parent compounds and their TPs at the different stages of treatment and will come up with relationships between operational parameters and contaminants’ removal including total mineralization, and partial transformations.
Recovery of nitrogen and phosphorous from digested sludge liquor has been proven as an alternative through struvite precipitation. Nevertheless, the recovery of ammonium and phosphorous with struvite requires a more deep study related to the excess ammonium generated as well as the use of chemicals (magnesium or potassium salts). This ESR will focus on the study of the combination of ammonium struvite plus anaerobic ammonium oxidation from the liquid fraction of the digested sludge in terms of nitrogen and phosphorous recovery as well as their impact on the whole water line. The following topics will be studied:
1. Lab-scale evaluation for NH4-struvite plus one stage anaerobic ammonium oxidation: operational conditions, quality and operational cost, influence over water line.
2. Lab-scale evaluation of operational conditions for one stage anaerobic ammonium oxidation plua K-struvite precipitation: operational conditions, quality and operational cost, influence over water line.
3. Design, construction and operation of a pilot plant for (NH4-or-K struvite and anaerobic ammonium oxidation) according to the previous results.
With the result obtained a suitable reject water treatment should be identified in order to optimize the nutrients recovery and the energy efficiency of the water line according to the removal of nitrogen from reject water. Also, because of the industry-academy development of the PhD, the knowledge transfer of the outcomes will give at the industry a possible technology development to reach the market within a period between 4-5 years.
Resilience is the capacity of a system to survive, adapt, and grow in the face of unforeseen changes. Urban resilience is the capacity of individuals, communities, institutions, businesses, and systems within a city to survive, adapt, and grow no matter what kinds of chronic stresses (urban expansion) and acute shocks (floods) they experience. The concept originated from the field of ecology (Folke, 2006) but the engineering sector is reshaping and incorporating it into the planning and design of urban infrastructure. Recent debates place resilience in the core of sustainability, as systems need to become resilient to become sustainable (Moddemeyer, 2015), with the ambition that resilience is considered a boundary concept in sustainability research (Olsson et al., 2015).
With growing interest from utilities, practitioners, and researchers in the incorporation of resilience into urban wastewater treatment systems, it is important to develop projects to study and implement resilience theory into wastewater treatment research.
The goal of the thesis is to study how resilience theory can be applied in the urban wastewater sector, to improve current management and contribute to the sustainability of the sector. This will be achieved by reviewing the current status in the water sector, by developing a model-based approach to demonstrate the incorporation or resilience theory, and the illustration of the proposed the usefulness of the approach by applying it to a benchmark case-study. It is also planned to study the role of resilience in the framework of Life’s design guideline from the perspective of wastewater treatment.
Water managers are facing emerging challenges in urban wastewater systems pushed by societal, economical and technological changes. In order to evaluate how well the system meets specific objectives influenced by current and emerging challenges, relevant indicators are employed. The objective of this research topic is to develop an Environmental Decision Support System (EDSS) to assess the technical, environmental and socio-economic aspects for WWTP upgrade. A sub-objective is to include uncertainty into the EDSS to make more qualified decisions.
The ESR candidate will integrate different knowledge representation techniques, such as mathematical models and knowledge-based systems, together with various economic, social and environmental criteria to assess sustainability and technical feasibility of proposed measures, using, whenever it is possible, a model-based scenario analysis. Specifically, the ESR will come up with a methodology (based on EDSS principles) to tackle WWTP upgrades for microcontaminants removal and for nutrient recovery providing a set of recommendations to decision-makers. The ESR will get training on uncertainty assessment to make sure that all solutions provided by the EDSS will come along with an uncertainty range, related to variability in the considered variables or unknowns.