Dr. Riaan van der Merwe is currently employed as an Assistant Professor in the Dept. of Civil Infrastructure and Environmental Engineering at Khalifa University, Abu Dhabi. He led efforts across the multi-disciplinary areas of desalination, ecological- and coastal engineering, coastal resilience, marine habitat enhancement/restoration, and sustainability science. Riaan is also conducting complex applied research-, and has significant Environmental Impact Assessment (EIA) & consultancy experience. He successfully led and completed more than 40 comprehensive EIAs (in the Kingdom of Saudi Arabia) across various domains, incl. social-ecological systems, marine environments, desalination, oil & gas, and a broad array of renewable energy projects. He is also been invited to talk at high-profile meetings on the topics of decarbonizing desalination, the recovery of minerals from brine, and nature-based approaches (specifically about desalination discharges).
Assessing Photothermal Membranes’ Potential for Direct Solar Membrane Distillation (Student: Lobna Issa Nassar (PhD); Supervisors: Dr Riaan van der Merwe & Dr Shadi Hasan))
This project aims to develop a novel membrane distillation (MD) method that captures sunlight and converts it to heat at the membrane surface, providing the thermal driving power for the MD process. This method solves the primary restriction of temperature polarization found in traditional MD procedures and considerably improves MD's energy efficiency. When treated with simulated sunlight, nanoparticle-coated membranes in a bench-size direct contact membrane distillation system enhance distillate flow while maintaining salt rejection and liquid entry pressure. This highlights photothermal membranes' potential for direct solar MD.
The use of the baited remote underwater videos (BRUVs) and the HYbrid Coordinate Ocean Model (HYCOM) to understand drivers of environmental change: A case study to enhance shark protection efforts in the Arabian Gulf (Shaikha Mohamed Abdalla Saifan Alsuwaidi (MSc); Supervisors: Dr Riaan van der Merwe & Dr Maryam Al-Shehhi))
Data from baited underwater videos (BRUVs) is used to document elasmobranch diversity, abundance, and distribution across the central-, eastern,- and western regions of the Arabian Gulf. The data is used to confirm species habitat association, and to determine if sharks and rays prefer/evade certain environmental conditions. The findings from the study can help regulators with recommendations on effective management measures especially when it comes to the protection of this species.
The Climate of the Arabian Peninsula: Trends and Future Predictions (Student: Alisha Sudhir Chandran (PhD); Supervisors: Dr. Riaan van der Merwe & Dr. Diana Francis))
Currently, there is a lack of accurate climate projections over the AP, since most of them are based on global climate models that do not cover the specificities of the AP climate. This research project aims to look at climate phenomena such as atmospheric circulation/warming, dust activity, etc. specific to the region and model projections and derive conclusions from the results, to get a better understanding of the future climate of the region.
Committees: (Scientific/Technical)
IAHR/IWA Joint Committee on Marine Outfall Systems
Memberships:
International Association for Hydro-Environment Engineering and Research
International Desalination Association
Association of Environmental Engineering & Science Professors
WateReuse Research Foundation
Institute of Environmental Management and Assessment
Journal Publications:
1. Siefan, A., Rachid, E., Elashwah, N., AlMarzooqi, F., Banat, F., & van der Merwe, R. (2022). Desalination via solar membrane distillation and conventional membrane distillation: Life cycle assessment case study in Jordan. Desalination, 522, 115383. https://doi.org/10.1016/j.desal.2021.115383
2. van der Merwe, R. (2021). “Shark Fishing in the United Arab Emirates: A Conservationist's Plea for Enhanced Protection and Sustainable Species Management.” International Journal of Conservation Science 12 (2), 613-624. http://ijcs.ro/public/IJCS-21-46_vanderMerwe.pdf
3. van der Merwe, R., Morelissen, R., Polman, H., & Jenner H. (2020). “Shifting the Discharge Mind-Set from Harmful to Habitat: Exploring Inventive Designs and Benefits of Underwater Discharge Structures.” Desalination and Water Treatment 195: 79–86. https://doi.org/10.5004/dwt.2020.25898.
4. Röthig, T., Ochsenkühn, M. A., Roik, A., van der Merwe, R., & Voolstra, C. R. (2016). Long?term salinity tolerance is accompanied by major restructuring of the coral bacterial microbiome. Molecular Ecology, 25(6), 1308–1323. http://doi.org/10.1111/mec.13567
5. van der Merwe, R., Röthig, T., Voolstra, C.R., Ochsenkühn, M.A., Lattemann, S., & Amy G.L. (2014). High salinity tolerance of the Red Sea coral Fungia granulosa under desalination concentrate discharge conditions: an in situ photophysiology experiment. Front. Mar. Sci. 1:58. https://doi.org/10.3389/fmars.2014.00058
6. van der Merwe, R., Bleninger, T., Acevedo-Feliz, D., Lattemann, S., & Amy, G.L. (2014). Combining autonomous underwater vehicle missions with velocity and salinity measurements for the evaluation of a submerged offshore SWRO concentrate discharge. J. Appl. Water Eng. Res. 2, 1–22. https://doi.org/10.1080/23249676.2014.980443
7. van der Merwe, R., Hammes, F., Lattemann, S., & Amy, G.L. (2014). Flow cytometric assessment of microbial abundance in the near-field area of seawater reverse osmosis concentrate discharge. Desalination, 343, 208–216. https://doi.org/10.1016/j.desal.2014.01.017
8. van der Merwe, R., Lattemann, S., & Amy, G.L. (2012). A review of environmental governance and its effects on concentrate discharge from desalination plants in the Kingdom of Saudi Arabia. Desalination and Water Treatment, 51(1-3), 262–272. https://doi.org/10.1080/19443994.2012.693700
