SG MEM

Wetting has been a major obstacle to the widespread adoption of membrane distillation (MD) technology. In MD modules, trapped water on the permeate side can only be removed by draining the modules, which can disrupt the process. The hollow fibers in typical MD units are susceptible to wetting due to a variety of factors, which can reduce their efficiency. In addition, frequent manual intervention is required to drain the water from MD modules. This technology relates to a water trap system that automates the removal of trapped water from MD modules. The Water-Trap System prevents the accumulation of liquid inside the modules, eliminating the need for manual intervention to stop the process and drain the modules. This can extend the lifespan of the membranes. The system is compatible with any type of membrane (hollow fibers or flat sheet spiral wound). A new module design with a water trap connection for drainage is also included. This new water trap design can be used to improve existing MD systems, increasing the production of pure water or valuable concentrates and extending the lifespan of MD units, especially those with membranes that are more prone to wetting

Current state-of-the-art lab-scale methods for fabricating superhydrophobic membranes for membrane distillation often involve complex surface modifications or the use of nanomaterials. However, these methods are difficult to scale up. This technology relates to a pure rheological spray-assisted non-solvent induced phase separation (SANIPS) approach to fabricate superhydrophobic polyvinylidene fluoride (PVDF) membranes. The resulting membranes have high porosity, superhydrophobicity, high liquid entry pressure, and hierarchical micro/nanostructures. They can also be easily scaled up. The spraying step caused local distortion of the membrane surface, which induced a two-stage phase inversion. This led to the formation of multilevel polymeric crystal structures. The morphological structures and other membrane properties (e.g., mechanical strength and liquid entry pressure) could be tuned by applying spraying materials with different physicochemical properties. This facile fabrication method will pave the way for the large-scale production of superhydrophobic membranes for membrane distillation.

Thin film composite (TFC) membranes are the main membrane types for reverse osmosis (RO) and nanofiltration (NF) membranes. RO membranes can be used for desalination, utility water treatment, wastewater treatment and reuse as well as process water treatment. NF membranes can allow monovalent ions, such as sodium chloride, to pass through the membrane, while rejecting divalent and multivalent ions, such as sodium sulfate. It has applications in the diary, food, dye, biotech, pharmaceutical and industrial processes for concentrating targeted streams. Boosting membrane permeability without a decrease in their rejection to target ions has been the objective of many membrane producers. Many methods have been proposed in literature to achieve the target, such as incorporating nanoparticles or surfactants. However, the synthesis of uniform nanoparticles in large scale is a problem and the long-term stability of nanoparticles in the polyamide layer is of concern. The process of adding surfactants is also not controllable, leading to a potential concern for quality control in the final membrane product. This invention relates to a simple method to increase the water permeability of thin film composite membranes for nanofiltration and reverse osmosis by 2 to 5 times.

Thin-film nanocomposite (TFN) membranes are a promising technology for desalination to increase water permeability of thin-film composite (TFC) membranes without compromising selectivity. However, their widespread use has been limited by the time and resources required to synthesise the necessary nanomaterials.  This invention relates to a methodology to form TFN membranes directly on TFC membranes, resulting in membranes with enhanced water permeability with little compromise on salt rejection. 

Seawater reverse osmosis (SWRO) is the state-of-the-art technology to transform the inexhaustible supply of seawater into freshwater to alleviate water stress worldwide. Nevertheless, the least energy-intensive seawater desalination plant still consumes around 3 kWh per m3 water produced, which is three to four times higher than surface water treatment. Thus, the biomimetic membrane is explored to improve the energy efficiency to maintain the sustainability of seawater desalination. A unique aquaporin-based biomimetic membrane (ABM) is formulated by incorporating the water channel proteins, aquaporins, into a polyamide membrane matrix to fabricate ultra-permeable SWRO membrane for clean water production. This robust ABM can be operated at the harsh condition of the desalination plant, i.e., high salinity, high operating pressure and extreme chemical cleaning process for the membrane. In addition, the ABM exhibits excellent performance stability and antifouling propensity. Most importantly, it is scalable to the industrial production level. The technology owner is interested in seeking technology licensing collaborators or manufacturing partners.

Reclaimed water is a critical source of water in Singapore and globally. Common practical limit of existing technology based on microfiltration/ultrafiltration-membrane bioreactor (MF/UF-MBR) and reverse osmosis (RO) for water reclamation has 75-85% recovery due to RO membrane fouling. This technology presents a hybrid system consisting of a high retention nanofiltration-membrane bioreactor (NF-MBR) and RO developed to achieve ≥90% of water recovery. NF-MBR produces superior quality effluent because the NF membrane can retain low molecular weight organics and scale forming divalent ions. Thus, membrane fouling in downstream RO process can be alleviated significantly, which allows higher recovery.

Membrane technology has been widely utilized in the water industry while niche applications such as protein separations are relatively lesser known. For protein clarification and concentration processes, decanter centrifuges and hydro-cyclones are usually deployed but may not achieve the required separation quality. Membrane separation methods have proven to bring better separation quality given an edge to potential adopters. This technology relates to a hollow fiber Microfiltration (MF) & Ultrafiltration (UF) membrane developed by the technology owner that can replace decanter centrifuge as a concentration method. The technology owner is seeking co-development partners to explore membrane applications in protein clarification and concentration. Building on a strong foundation in membrane substantial know-how in membrane process separation industries, the technology owner would like to partner with the alternative protein and food industry to test bed the hollow fiber membrane technology.

The chemical separation industry is highly energy intensive. It accounts for about 15% of world’s energy consumption and is one the world’s largest silent polluters, producing more than 10% of the annual global greenhouse gas (GHG) emission. To tackle this challenge, the technology provider has developed solvent-resistant nanofiltration membranes with nanosized pores to achieve chemical separations at a molecular level without the use of heat. By integrating the technology into the chemical separation processes, this technology can reduce their energy consumption and GHG emissions by 90% and lower their operating cost by up to 50%. The technology provider is seeking industrial partners for collaboration opportunities and would like to work with partners to identify and solve their pain points in chemical separation processes by utilizing this nanofiltration technology.

Compared to other desalination technologies, membrane distillation (MD) possesses several advantages, including the tolerance to high salinity, the capability to leverage low-grade heat sources, and the low capital expenditure. However, MD faces the problems of membrane wetting and fouling when desalinating wastewater and seawater with complex compositions. Membrane wetting is a prominent challenge to MD because it allows direct permeation of the salty feed across membrane pores, resulting in salt passage and process failure. The inherent hydrophobicity of conventional MD membranes increases the fouling propensity of organic foulants (e.g., proteins and oil). This blocks the membrane pores, which leads to a lower water productivity. Oil-induced fouling is particularly relevant to MD because MD has been extensively explored and shown promising to desalinate the produced water from hypersaline shale oil/gas streams. This technology relates to a novel NF/MD membrane to combat the issue of surfactant-induced wetting in MD. A dense top layer, which mimics the selective layer of NF membranes, is constructed on top of a polyvinylidene fluoride (PVDF) MD membrane. The technology owner is currently seeking interested commercial entities to license the technology and develop it into a product.