China emits more than 70 billion tons of sewage each year and membrane treatment accounting for over 95% of China’s waste water recycles, which is estimated to reach a market value of around 60 billion yuan in 2022. However, at present, markets for raw materials and high-end products are mostly monopolized by foreign enterprises. Through moistening polyethylene(PE) membrane with mini punctures, embedding modification and cross-treatment, SEMCORP has developed sustainably hydrophilic membrane material that costs less than half of common products and thus has substantial market competitiveness.

Compared to traditional water treatment methods, membrane has advantages such as low chemical separation cost, small area coverage, simple technologies, widespread application and sound water quality. At present, more than 90% of domestic raw materials for membrane bio-reactor comes from polyvinylidene difluoride(PVDF) which is not only expensive, but also monopolized by Dow Chemical of the US, Toray, Mitsubishi and Suez Environment of France; polysulfone(PSF) SMS materials for reverse osmosis(RO) membrane are mainly monopolized by foreign enterprises such as Solvay S.A., Mitsubishi, etc.

PE materials have advantages such as high output, low cost, resistance to strong acid and alkali, but are hampered from mass commercialization in water treatment for its drawbacks such as strong hydrophobicity, easy oxidation, low strength, etc. Based on current R&D of macromolecular materials, SEMCORP developed PE membrane technologies such as double hydrophilicity, puncture distribution, interfacial polymerization, etc., and products such as low-cost membrane bio-reactor(membrane module), super low pressure RO membrane, etc.

Based on ultra-thin film membrane technology, SEMCORP’s MBR membrane(membrane module) is very resistant to pollution, with restoration rate for initial clean water filtration over 99% and COD elimination rate over 90%. This membrane does not need moistener for it is not subject to damages caused by aridity, and thus trumps products made of PVDF materials. Already validated through pilot-scale experiments given by clients, this product is now being accelerated in commercialization.

SEMCORP ultra-low pressure RO membrane has thickness one sixth of that of PSF materials, covers small areas and is thus widely applicable. It boasts ion retention rate over 99% and filtration volume over 8L/m/hr, and does not need sealing by protection fluid for it is not subject to puncture shrinking or oxidation, which is why it trumps RO membrane made of PSF materials. This membrane has already entered the sector of home water filters and is now being accelerated in commercialization for the industrial sector.

2023 is both the year of “resource utilization” and “l(fā)ow-carbon development”. Based on the equipment and technological advantages in battery polyethylene separator, SEMCORP has innovated PE hydrophilic modification membrane that has low cost and high functionality, comprehensively improving China’s core competitiveness in the materials sector.