RESEARCH SHOWCASE 2023
School of Civil and Environmental Engineering, UTS
The School of Civil and Environmental Engineering Research Showcase was held on Friday 29 September 2023 at University of Technology Sydney Campus.
Our NiCE Hub's PhD student, Weonjung Sohn, achieved remarkable success at the CEE Research Showcase. She secured the 3rd Best Oral Presentation (Session 2) and the 2nd Best Poster Presentation awards for her presentation on Nutrient Recovery from Source-Separated Urine in a Compact Membrane Bioreactor! Check out the research abstract below.
3rd Best oral presentation (Session 2), 2nd Best Poster presentation
"Nutrient Recovery from Source-Separated Urine in a Compact Membrane Bioreactor"
The global fertiliser market price has soared in recent years along with the increasing world population and the agricultural demand. This continuous production of synthetic fertilisers would affect the resource availability due to the phosphorous extraction from mines as well as the fixation of atmospheric nitrogen. Source separation of urine can be an effective solution for nutrient recovery as a fertiliser, as well as reducing a dependence on synthetic fertilisers. The biological oxidation in a membrane bioreactor (MBR) can be a promising technology in reducing odorous organics and pH in hydrolysed urine as well as stabilising by partial conversion of ammonia into nitrate. However, long hydraulic retention time (HRT) of the MBR remains one of the major challenges of which reduces energy efficiency and increases footprint. In this study, a powdered activated carbon (PAC) incorporated MBR with biofilm carrier addition was operated to investigate their effects on the enhancement of nitrification rates and their HRT. Consequently, the incorporated MBR displayed a 36% higher nitrification rate and 40% reduced HRT compared to the conventional MBR. The microbial community analysis showed significant shifts in microbial compositions were observed across different sludge growth forms. This study therefore shows that PAC and biofilm carrier incorporated MBR is more compact and high-performing contributing to commercial applications and helping achieve circular economy of nutrients.
CECE 2023 Conference Awards
Aerial Function Centre, UTS
The Circular Economy for Climate and Environment (CECE) 2023 Conference was held on 26-27 September 2023 at the Aerial Function Centre at University of Technology Sydney Campus.
Jade Jiang and Andrea Merenda, post-doctoral researchers in our NiCE Hub, have secured the Best Poster Presentation awards at CECE 2023! Check their 3-min poster presentations below.
Dr. Jade Jiang
Best Poster presentation in CECE2023
"Potential nutrient recovery from source-separated urine through hybrid membrane bioreactor and membrane capacitive deionisation"
Human urine is rich in nutrients and an important source of fertilisers, especially when source-separated urine is available. Due to the increasing focus on the need for nutrient removal and recovery, various technologies and processes are being investigated. This study investigated a hybrid membrane bioreactor (MBR) and membrane capacitive deionisation (MCDI) where the source-separated urine was treated in MBR, and the subsequent MBR permeate was used as a feed for the MCDI for further nutrient removal and recovery. Overall, nitrate, phosphate and ammonium removal were 66%, 49% and 58%, respectively, in the treated urine using MCDI. Additionally, the recovery rate of nitrate, phosphate and ammonium were 80%, 64% and 76% in the concentrated brine. The energy demand for recovery of NH4+ was between 3.03-11.25 kWh/kg of NH4+-N and between 3.87-14.75 kWh/kg of NO3--N for the three different voltages used in the study. The study further demonstrates the viability of MCDI application for nutrient recovery and concentration, effectively using both the adsorption and desorption phases of MCDI operation without using any chemicals.
Dr. Andrea Merenda
Best Poster presentation in CECE2023
"Catalytic membrane reactors for energy efficient wastewater treatment"
The United Nations have identified the availability and access to clean and safe water worldwide as key challenges towards sustainable economic growth, spurring the development of resilient and efficient water supply systems while tackling social inequalities and climate change. Advances in the design and synthesis of photo- and electro-driven catalysts have fostered the design of stimuli-responsive membrane reactors for innovative advanced oxidation processes. Stimuli-responsive membrane reactors can integratemembrane separation with the catalytic removal of pollutants. Renewable energies, such as solar irradiation and green electricity, can be utilized to produce oxidising species on the photo- or electro-active surface of membranes, greatly enhancing the removal of waterborne pollutants. Catalytic membrane reactors are however characterised by low technological readiness levels, with scarce reports of pilot or industrial-scale applications. Here, we investigate the synthesis of catalytic membrane reactors by designing stimuli-responsive materials with controlled nanoscale order and interface. This study focuses on the deposition of ultrathin metal oxide layers (TiO2, ZnO) on conductive and porous stainless steel membranes by atomic layer deposition. The formation of Schottky barriers and type II heterojunctions results in higher density of charge carriers with mitigated recombination phenomena, enhancing the catalytic performance. The synergy between photo and electrocatalytic degradation phenomena is elucidated by the definition of a new photoelectrocatalysis enhancement factor, which reveals that photoelectrocatalytic kinetics are 2-3 times higher than the respective photo or electro-driven reactivities. Furthermore, type II heterojunctions with controlled thickness and layer ordering achieved kinetic constants up to 75 10-3 min-1 in the degradation of persistent organic pollutants, corresponding to a 500% increase compared to single metal oxide layers. Photoelectrocatalytic filtration experiments are also discussed, with a focus on bulk and surface degradation phenomena. The rational design of catalytic membrane reactors endowed with cost-effectiveness and competitiveness can lay the foundations of new energy-efficient advanced oxidation processes in wastewater treatment.
Visualise Your Thesis 2023
Visualise Your Thesis is an international competition that challenges research students to present their research to a non-specialist audience in a 60 second video.
Transformation of urine to fertiliser for a circular economy
School of Environmental Engineering
RESEARCH SHOWCASE 2022
School of Civil and Environmental Engineering, UTS
The School of Civil and Environmental Engineering Research Showcase was held on Wednesday 28 September 2022 at University of Technology Sydney Campus.
Congratulations to the winners, who presented the impact of urine diversion and nutrient recovery from urine!
Check their research abstract below.
2022 CEE Research Showcase winners
Best oral presentation (1st winner, Session 2)
"Impact of urine diversion on a decentralised wastewater recycling plant"
In this study we have developed a model to estimate the energy consumption, greenhouse gas emissions and volumetric nitrification rate for treatment of source separated urine at a decentralised wastewater treatment plant. Firstly, we calibrated and validated the model with published real data at a lab scale. The model was further upscaled and used to investigate the performance of a full scale system. The simulations showed that at optimised DO set point (3mg/L) energy consumption was found to be 3kWh/kgN and greenhouse emissions of 25.6 kgCO2e/m3 at a volumetric nitrification rate of 310 mgN/L/d. The energy required for conventional treatment process and modified treatment process with urine separation and treatment were compared. The modified treatment process (including urine treatment) showed about same energy demand but slightly reduced GHG emissions and plant footprint in comparison to the conventional process. In the conventional process, no nutrients are recovered whereas modified treatment process with urine diversion and treatment can recover nitrogen in the form of a stable liquid nitrogen fertiliser which can be used for onsite fertigation or further be concentrated and transported to agricultural farmlands.
Best poster presentation (3rd winner)
"Nutrient recovery from human urine using membrane technology"
Source separation and recovery of human urine have often been proposed as an effective way to achieve a more sustainable circular economy cycle. The high density of available nutrients, including Nitrogen, Phosphorous, and Potassium in urine, makes it an ideal raw material for producing fertiliser. Harvesting nitrogen from separately collected urine can potentially reduce the cost and energy consumption of wastewater nitrogen removal and fertiliser production. The high ammonia concentration in source-separated urine offers promising opportunities for nitrogen recovery. However, odour and pathogens must be removed to improve the safety and general acceptance of urine-based fertilisers. As a result, separating and harvesting nitrogen from urine sources is more favourable for removing all contaminants like bacteria and viruses. Membrane distillation (MD) is a promising hybrid thermal membrane separation technology that can efficiently separate volatile compositions from the feed stream. However, the relatively low flux and the presence of fouling or wet ting agents in feed solution negate the applicability of MD for long-term operation. This study employs a hydrophobic membrane in Membrane Distillation Setup to recover ammonium fertilisers from human urine. Moreover, the Inkjet printing method is used to modify membranes to improve their antifouling performance.