New Breakthrough in Semiconductor Wastewater Recycling: NTU Proposes Electrically Driven Separation and Concentration Technology

(Central News Agency, reporter Zhao Minya, Taipei, 10th) Taiwan's semiconductor industry is highly dependent on water resources. Fluoride-containing wastewater generated during the manufacturing process has long been considered a high-cost, high-burden棘手 problem due to the difficulty of treatment and reuse. A research team from National Taiwan University has proposed an electrically driven separation and concentration technology that can convert difficult-to-use, low-concentration fluoride-containing wastewater into reusable循环 resources, also helping to reduce the cost of semiconductor wastewater reclamation.

The National Science and Technology Council (NSTC) held a press conference on the research results today. With the support of the NSTC, a research team led by Distinguished Professor Hou Jia-Hong from the Graduate Institute of Environmental Engineering at National Taiwan University proposed an innovative electrically driven separation and concentration technology. This technology elevates low-concentration fluoride-containing wastewater to medium-high concentrations, allowing manufacturers to further resource it and convert it into cryolite, while simultaneously reducing water reclamation treatment costs.

Professor Hou pointed out that fluoride-containing wastewater is prevalent in semiconductor and electronics manufacturing processes, especially low-concentration wastewater. Traditionally, it is treated by chemical precipitation, forming calcium fluoride sludge. This not only makes resource recovery difficult but also increases the burden of sludge disposal, subsequent treatment, and carbon emissions. Although high-concentration fluoride-containing wastewater can currently be further converted into cryolite for use in the aluminum manufacturing and ceramic industries, low-concentration wastewater still lacks a concrete, feasible solution due to insufficient recovery efficiency and economic benefits.

He stated that the research team partnered with Fengpei Environmental Technology Co., Ltd., a company with long-term expertise in the resource recovery of fluoride-containing wastewater from semiconductors, to introduce Membrane Capacitive Deionization (MCDI) technology and develop a new strategy for concentrating low-concentration fluoride-containing wastewater.

Professor Hou explained that the technology uses an electric field to drive ion movement and adsorption, effectively removing and concentrating charged ions in the water. It offers advantages such as no need for chemical addition, no generation of chemical sludge, modular design, and high recovery potential. The team built a laboratory-scale system, treating approximately 100 liters of fluoride-containing wastewater per day, successfully concentrating the low-concentration wastewater to a concentration range suitable for cryolite preparation. They completed system integration and on-site factory testing, confirming its feasibility for resource recovery and providing a new solution for the semiconductor industry to move towards low-carbon emissions and circular sustainable development.

Professor Hou stated that to verify the feasibility of scaling up the technology and implementing it in factories, the team scaled the system up tenfold, building a packaged capacitive fluoride ion concentration system capable of treating 1 ton of wastewater per day. This marks a critical step towards industrial application. Research shows that by optimizing materials and replacing traditional metal current collectors with graphite sheets, system stability and durability can be improved, and carbon emissions can be significantly reduced.

Fan Zhen-Xuan, Executive Director of the Net Zero Water Technology Group at NTU's New Carbon Research Center, pointed out that the technology is already feasible and that the semiconductor industry has related needs. However, their existing wastewater treatment facilities are already in place, and introducing new equipment could affect the original design. Therefore, it is likely to be implemented in future new factory construction.

Fan stated that the team has established the Net Zero WaterTech Hub at NTU's Zhubei Campus and set up a collaborative laboratory with Fengpei Company. This serves as an important venue for technology demonstration, collaboration matching, and industrial training, allowing research results to extend from the laboratory to the industrial site, connecting key elements such as technology validation, talent cultivation, and application promotion. (Editor: Lin Shuyuan) 1150610