1. Membrane-based Processes for Industrial Wastewater Treatment and Reuse
Industrial activities consume substantial amounts of freshwater while generating vast quantities of wastewater. Recently, recovery and recycling of industrial wastewater has become a growing trend due to the rising water demand. Membrane-based processes, such as reverse osmosis (RO) and membrane distillation (MD), can play a key role in industrial wastewater treatment and reuse. However, the complexity of industrial wastewater largely influence the water recovery and energy consumption of these technologies. In the Tong lab, we are working on developing new membrane materials and processes to improve the performance of membrane technologies in treating typical industrial wastewater. Due to the intensive activities of shale oil and gas production in the state of Colorado, we are currently focusing on applying membrane technologies to the treatment of shale oil and gas produced water. We are fabricating and testing novel membrane materials that are resistant to fouling and scaling during the treatment process, and designing effective pre-treatment processes to lower the fouling and scaling potentials of the produced water.
Industrial activities consume substantial amounts of freshwater while generating vast quantities of wastewater. Recently, recovery and recycling of industrial wastewater has become a growing trend due to the rising water demand. Membrane-based processes, such as reverse osmosis (RO) and membrane distillation (MD), can play a key role in industrial wastewater treatment and reuse. However, the complexity of industrial wastewater largely influence the water recovery and energy consumption of these technologies. In the Tong lab, we are working on developing new membrane materials and processes to improve the performance of membrane technologies in treating typical industrial wastewater. Due to the intensive activities of shale oil and gas production in the state of Colorado, we are currently focusing on applying membrane technologies to the treatment of shale oil and gas produced water. We are fabricating and testing novel membrane materials that are resistant to fouling and scaling during the treatment process, and designing effective pre-treatment processes to lower the fouling and scaling potentials of the produced water.
2. Mitigation of mineral scaling to improve water recovery of membrane desalination
Mineral scaling is a primary barrier that constrains the performance of membrane desalination. As feedwaters are concentrated during desalination processes, solute concentrations can exceed the solubility of certain sparingly soluble solids. The subsequent precipitation of mineral scales on the membrane surface reduces water productivity and membrane lifespan, and compromises the cost and energy efficiencies of membrane desalination. However, as compared to extensive progress made on understanding and controlling organic and biological fouling, our knowledge on mineral scaling is limited and current strategies of scaling mitigation is costly and ineffective. Therefore, the Tong lab is working on promoting the knowledge on the mechanisms underlying mineral scaling in membrane desalination, and developing new strategies to reduce membrane scaling. In particular, we are combining interdisciplinary expertise in membrane separation, aquatic chemistry, geochemistry, and biomineralization to investigate the influence of membrane surface chemistry on the formation of mineral scales at the membrane-water interface. The resultant findings will guide our long-term efforts to design and develop new membrane materials with improved resistance to mineral scaling.
Mineral scaling is a primary barrier that constrains the performance of membrane desalination. As feedwaters are concentrated during desalination processes, solute concentrations can exceed the solubility of certain sparingly soluble solids. The subsequent precipitation of mineral scales on the membrane surface reduces water productivity and membrane lifespan, and compromises the cost and energy efficiencies of membrane desalination. However, as compared to extensive progress made on understanding and controlling organic and biological fouling, our knowledge on mineral scaling is limited and current strategies of scaling mitigation is costly and ineffective. Therefore, the Tong lab is working on promoting the knowledge on the mechanisms underlying mineral scaling in membrane desalination, and developing new strategies to reduce membrane scaling. In particular, we are combining interdisciplinary expertise in membrane separation, aquatic chemistry, geochemistry, and biomineralization to investigate the influence of membrane surface chemistry on the formation of mineral scales at the membrane-water interface. The resultant findings will guide our long-term efforts to design and develop new membrane materials with improved resistance to mineral scaling.
3. Smart design of membranes via tuning membrane surface properties
Membranes are the core component of membrane desalination systems, and high-performance membranes adaptive to complex feedwater composition are the key to improve the economic feasibility of membrane desalination. In our lab, we are designing smart membranes via tuning membrane surface properties such as hydrophilicity, texture, surface charge, and surface energy. By doing so, we are able to create membranes possessing exceptional fouling/scaling/wetting resistance for various membrane desalination technologies. Especially, our recent work (Nature Communications, 2019, 10, 3220) indicates that a trade-off exists between wetting resistance and water vapor permeability in membrane distillation. Thus, we are attempting to design and fabricate membranes with both high wetting resistance and water vapor permeability. Also, we are currently working on developing scaling-resistant membranes, which have not received as sufficient attention as fouling-resistant membranes.
Membranes are the core component of membrane desalination systems, and high-performance membranes adaptive to complex feedwater composition are the key to improve the economic feasibility of membrane desalination. In our lab, we are designing smart membranes via tuning membrane surface properties such as hydrophilicity, texture, surface charge, and surface energy. By doing so, we are able to create membranes possessing exceptional fouling/scaling/wetting resistance for various membrane desalination technologies. Especially, our recent work (Nature Communications, 2019, 10, 3220) indicates that a trade-off exists between wetting resistance and water vapor permeability in membrane distillation. Thus, we are attempting to design and fabricate membranes with both high wetting resistance and water vapor permeability. Also, we are currently working on developing scaling-resistant membranes, which have not received as sufficient attention as fouling-resistant membranes.
4. Environmental Applications and Implications of Engineered Nanomaterials
The 21st century is currently experiencing a transition of nanotechnology from discovery to commercialization. The unique and novel physicochemical properties of engineered nanomaterials (e.g., small size, high surface area and reactivity, tunable surface functionality) have opened unimagined opportunities for engineering, scientific, and medical applications. The Tong lab is seeking to apply novel nanomaterials to water and wastewater treatment, such as incorporation of nanomaterials into desalination membranes for fouling and scaling mitigation. Also, we are interested in understanding the fate, transformations, and toxicity of nanomaterials, in order to design sustainable nanomaterials with minimized environmental consequences.
The 21st century is currently experiencing a transition of nanotechnology from discovery to commercialization. The unique and novel physicochemical properties of engineered nanomaterials (e.g., small size, high surface area and reactivity, tunable surface functionality) have opened unimagined opportunities for engineering, scientific, and medical applications. The Tong lab is seeking to apply novel nanomaterials to water and wastewater treatment, such as incorporation of nanomaterials into desalination membranes for fouling and scaling mitigation. Also, we are interested in understanding the fate, transformations, and toxicity of nanomaterials, in order to design sustainable nanomaterials with minimized environmental consequences.