Research Area
Membrane processes for water and wastewater treatment
Membrane technology is widely used in water and wastewater treatment processes. Currently, we focus on understanding the biological or physico-chemical phenomena occurring in various membrane water treatment systems, including membrane bioreactors (MBRs) for wastewater treatment, ultrafiltration for the pretreatment of seawater desalination, reverse osmosis (RO) for wastewater reuse, etc
Biofouling (biofilm) control by microbial signaling:
Quorum sensing (QS) and quorum quenching (QQ)
Recently, a novel molecular biological method has been reported that effectively mitigates the attachment and growth of microorganisms on the membrane surfaces in MBRs.
In 2009, Yeon et al. demonstrated a positive correlation between microbial quorum sensing (QS) and membrane biofouling in an MBR for wastewater treatment. Since then, a number of studies have noted the correlation between QS and membrane biofouling, and provided development of various quorum quenching (QQ) techniques for the elucidation and control of biofouling in MBRs. We focus on applying QQ strategy to various membrane water treatment processes as well as improving the efficiency of QQ-based biofouling mitigation in MBRs.
Nitric oxide (NO)-mediated biofilm dispersal
Recent discoveries regarding the regulation of the biofilm life cycle by bacterial signaling systems have identified novel strategies for manipulation of biofilm development to control the biofouling of membrane-based water purification systems. Nitric oxide (NO) signaling has been shown to induce dispersal of a wide range of single- and multi-species biofilms. We focus on applying NO-mediated biofilm dispersal in membrane water treatment process to mitigate the biofouling.
Improving biogas productino through QS technology
Developing alternative energy, which should be more efficient and eco-friendlier than fossil fuels, is very crucial these days. Biogas, such as bio-methane and bio-hydrogen, is one of the bioenergy types with high production globally and it can be produced from various substrates such as municipal waste, plant crops, anaerobic sludge, cellulosic biomass, food waste, and algae biomass. In the anaerobic digestion processes for producing methane or hydrogen, granulation and biofilm formation are considered the efficient strategy to enhance productivity. We focus on the roles of QS in the granulation of the anaerobic microbiome and the competition of biogas producing microbial with inhibiting community to improve the production efficiency.
Removal of microplastics in water systems
Microplastics are referring to small plastic particles smaller than 5 mm in size. They are produced by crushing large plastic pieces into smaller pieces through a weathering process and sometimes originated from specific products manufactured in the form of tiny beads (e.g., face and body scrub, toothpaste, etc.). As the environmental threats from the accumulation of microplastics in the water systems are increasing, we focus on the technologies to remove aquatic microplastics, such as membrane bioreactors and biodegradation by microorganisms.