What are the advanced chemical products wastewater treatment technologies?
chemical products enterprises have widely applied various advanced wastewater treatment technologies in environmental protection governance and standard discharge. They are upgrading from “end of pipe treatment” to a full process management mode of “process reduction recycling resource recovery”, achieving stable compliance of high difficulty wastewater, improving the reuse rate of reclaimed water, and synergistic resource utilization.
1、 Mainstream advanced processing technology and application characteristics
MBR (Membrane Bioreactor) Technology
The efficient combination of biodegradation and membrane separation can intercept high concentration activated sludge, significantly improving the efficiency of organic matter removal, especially suitable for chemical wastewater with complex composition and high pollutant concentration, such as printing and dyeing, petrochemical wastewater. Its excellent effluent quality, small footprint, and high degree of automation have become one of the core processes for advanced treatment.
The dual membrane process of ultrafiltration (UF) and reverse osmosis (RO)
As a key technology for wastewater reuse, the secondary treated effluent can be further purified to near pure water standards, and is widely used in scenarios such as cooling water replenishment, boiler feedwater, and process water reuse. This process achieves full reuse or near zero discharge of wastewater in industries such as steel, textile, and chemical. For example, Hegang Leting and Fujian Fengzhu Textile have achieved a water reuse rate of over 95% through this technology.
Advanced Oxidation Technologies (AOPs)
For difficult to degrade, toxic and harmful organic compounds (such as benzene rings and heterocyclic compounds), Fenton oxidation, ozone catalytic oxidation, wet oxidation and other technologies are used to decompose large molecular organic compounds into small molecules or mineralize them into CO ₂ and H ₂ O. For example, a chemical project uses the “Fenton oxidation method” as the tertiary treatment to ensure stable and compliant COD in the effluent.
Micro electrolysis technology (Fe-C micro electrolysis)
Suitable for the pretreatment of high concentration and difficult to biodegrade wastewater, it improves the biodegradability of wastewater by generating Fe ² ⁺ and new ecology [H] in situ, while also possessing multiple functions such as coagulation, phosphorus removal, and heavy metal reduction. This technology can be used as a “wall breaking” method for high concentration organic wastewater, improving the stability of subsequent biochemical systems.
Photocatalysis and Nanomaterial Technology
By utilizing nano catalysts such as TiO ₂ whiskers, difficult to degrade organic compounds can be efficiently degraded under light conditions. For example, COD in printing and dyeing wastewater can be reduced to below 50mg/L, and chromaticity can be significantly reduced. Although industrialization still faces challenges, engineering applications have been implemented in some high-end projects.
Membrane integrated resource utilization technology (such as nanofiltration+reverse osmosis+evaporative crystallization)
For high salt and heavy metal containing wastewater (such as electroplating and lithium battery recycling wastewater), membrane separation is used to achieve the separation and reuse of water and salt, combined with evaporation crystallization to recover salt or metal resources. For example, after membrane treatment, the nickel recovery rate of nickel containing rinse water is nearly 100%, and the water reuse rate reaches over 80%, truly achieving the goal of “turning waste into treasure”.
