PLENARY SESSION KEYNOTES
Plenary Session Keynotes
Agenda setting from the most prominent figures within the water sector and beyond. Keynote speakers are the top specialists in their field and will provide the overarching narrative for the conference. Delegates at LET 2023 will be able to gain from access to the insights of plenary keynote speakers, described below, and invited technical session keynote speakers.

Jonathan Clement
Ramboll, the Netherlands
Jonathan Clement currently is the Director of Global Advanced Water Treatment at Ramboll. Since 1997 he has focused on advanced water treatment technologies including ceramic membranes advanced oxidation, and ion exchange. In his previous role as CEO of PWN Technologies he led the application of two of the largest ceramic membrane plants in the world, including a 180,000 m3/day water treatment plant in Singapore.
His career has focused extensively on alternative treatment schemes for water reuse and drinking water to improve energy efficiency and reliability. These include combined steps of ozone and ceramic membranes. His current R&D focus in on desalination pre-treatment and low energy desalination. As the founder of the Leading Edge Technology (LET), he has chaired the conference for the first 6 years. He is past member of the IWA water reuse committee and is now chairing the technical programme committee of LET 2023. In 2013 he received a special award for outstanding leadership from the IWA. He has been listed as one of the top 25 global water leaders in the world.
Nikolay Voutchkov
ENOWA Water Innovation Center, Saudi Arabia
Nikolay Voutchkov is the Executive Director of the ENOWA Water Innovation Center. ENOWA is a world-class Energy, Water, and Hydrogen company founded in NEOM, Saudi Arabia. NEOM Water sector is focused on improving water performance sustainably, building off the implementation of a world class, smart and connected, water infrastructure in NEOM, utilizing the latest, and future innovation and technology with the best minds in the industry.
From 2009 to 2023, Mr. Voutchkov was the Founder and the Director General of Water Globe Consultants, a US company providing worldwide engineering consulting and training services in the field of desalination and water reuse worldwide. For 11 years prior to 2009, Mr. Voutchkov was a Chief Technology Officer and Corporate Director of Poseidon Resources, a US company specializing in developing desalination and water reuse projects. In this capacity, Mr. Voutchkov has served as an expert technical advisor to project developers of over a dozen desalination projects in the US, Mexico, Australia, the Middle East, South Africa, Indonesia, and Singapore.


Dr. Samuel Chui J.P.
Environmental Protection Department, Hong Kong SAR
Dr Samuel Ho Kwong Chui is the Director of the Environmental Protection Department of the Hong Kong SAR Government. He is also an Adjunct Professor of the Hong Kong University of Science and Technology. He has been working in the field of wastewater treatment for 30 years. During the COVID-19 pandemic, Dr Chui launched a territory-wide sewage surveillance programme for Hong Kong, helping to fight the virus.
For the past three years, the Covid-19 pandemic has had a significant impact on the entire world. Hong Kong, as an international and cosmopolitan city, has also been affected by the pandemic. Since December 2020, the Hong Kong Government has used sewage SARS-CoV-2 viral surveillance to allow informed planning of pandemic intervention actions. At the upcoming LET Conference in Daegu, Korea, he will present on Hong Kong’s expertise in employing sewage virus surveillance to tackle the pandemic.
Miriam Otoo
Tetra Tech, USA
Dr. Miriam Otoo is a senior economist with 15+ years of experience in research, policy and project implementation in WASH and natural resources management. She holds a PhD degree in Applied Economics from Purdue University, USA. She is the Deputy Chief of Party of an urban water and sanitation resilience research project at Tetra Tech, ARD. She specializes in urban sanitation, business innovations in wastewater and fecal sludge management, economics of water, energy and nutrient recovery, and solid waste management. She has worked extensively in sub-Saharan Africa and South Asia, and previously led the International Water Management Institute’s research program on Circular Economy and Pollution (previously named Resource Recovery and Reuse).


Jaehong Kim
Yale School of Engineering and Applied Sciences, USA
Jaehong Kim is Henry P. Becton Sr. Professor of Chemical and Environmental Engineering at Yale University where he served as a department chair from 2006 to 2012. Prior to joining Yale in 2013, he was Georgia Power Distinguished Professor at Georgia Institute of Technology. Kim received B.S. and M.S. degrees in Chemical Engineering from Seoul National University and a Ph.D. degree in Environmental Engineering from University of Illinois at Urbana-Champaign. His research focuses on environmental application of nanomaterials and single atom catalysts and catalytic/electrocatalytic advanced oxidation processes.
Xiaodi Hao
Beijing University of Civil Engineering and Architecture, China
A full professor in Beijing University of Civil Engineering and Architecture and an editor of Water Research. He acquired a BSc degree in Taiyuan University of Technology, an MSc degree in Harbin Institute of Technology, and a PhD degree in Delft University of Technology.
He has gained international work experience over 8 years, working in the Netherlands (TU Delft and TNO), France (CEMAGREF), Hong Kong (Poly-U and UST), United States (Auburn University), and Japan (Gifu University). His research interests are nutrient removal & recovery, modelling, and energy recovery from wastewater.


Zhiyong Jason Ren PhD
Andlinger Center for Energy and the Environment/Princeton University, USA
Dr. Zhiyong Jason Ren (@zjasonren) is a professor in the department of Civil and Environmental Engineering and the Andlinger Center for Energy and the Environment at Princeton University. He leads the Princeton WET (Water & Energy Technologies) Lab with research focusing on energy and resource recovery during environmental processes such as wastewater treatment and reuse, water desalination, and remediation (https://ren.princeton.edu). He currently leads several initiatives for water sector decarbonization and digitalization, including books and programs on water data infrastructure and literature mining. He has received various recognitions with most recent being a recipient of the 2020 ASCE Walter L. Huber Civil Engineering Research Prize.
Keynotes will frame the key discussions and topics that will be addressed during the Technical Sessions.