Persistent Organic Pollutants(POPs)
Persistent organic pollutants (POPs) pose a serious threat to the ecological environment and human health due to their environmental persistence, bioaccumulation, long-range transport, and high toxicity. Typical POPs include polychlorinated biphenyls (PCBs), dioxins (PCDD/Fs), and organochlorine pesticides (such as DDT).
UV/H2O2 POP degradation technology relies on the attack of free radicals (such as ·OH and SO4-) on POP molecules. The degradation process may include dechlorination, hydroxylation, and benzene ring opening, ultimately leading to the gradual conversion of POPs into small aliphatic acids, CO2, and H2O.
Endocrine Disrupting Chemicals(EDCs)
Endocrine disrupting chemicals (EDCs) are exogenous chemicals that can interfere with the normal functioning of the endocrine system. Even at extremely low concentrations, they can adversely affect reproductive, developmental, and immune systems. Common EDCs include bisphenol A (BPA), nonylphenol (NP), and phthalates (PAEs).
UV/H2O2 and UV/O3/H2O2 technologies are widely used to remove EDCs. Free radical oxidation of EDCs typically targets reactive functional groups within their molecules, such as phenolic hydroxyl groups, olefinic bonds, and benzene rings. OH attack can lead to fragmentation, hydroxylation, and ring opening, ultimately converting them into small organic acids, which may then undergo further mineralization.
Degradation of antibiotics
The widespread use and release of antibiotics has led to their ubiquitous presence in the environment. This not only poses direct ecotoxicity risks but, more seriously, can also induce and spread antibiotic resistance genes (ARGs), posing a long-term threat to public health.
Technologies such as UV/H2O2, UV/PS, and UV/chlorine (such as UV/CI2 and UV/NH2CI) have demonstrated excellent efficacy in degrading antibiotics. Free radicals attack the active sites of antibiotic molecules through electron transfer, hydrogen abstraction, or electrophilic addition, leading to the destruction of chromophores, chemical bond breakage (such as the opening of the β-lactam ring), and functional group transformation, thereby inactivating them.
New Pollutant Treatment Processes
Using UV-AOPs alone can be costly and inefficient when treating complex wastewaters or pursuing extreme removal rates. Therefore, combining them with other treatment technologies has become an important development direction.
UV-AOPs + Biological Treatment: UV-AOPs can be used as a pretreatment unit for biological treatment, converting recalcitrant macromolecules into easily biodegradable small molecules, thereby improving the biodegradability of wastewater (BODs/CODcr ratio).
Membrane Separation + UV-AOPs: Membrane separation technologies (such as ultrafiltration, nanofiltration, and reverse osmosis) can effectively remove suspended solids, colloids, and some dissolved organic matter. UV-AOPs can degrade trace organic matter, resulting in high-quality water.
UV-AOPs + Adsorption: Adsorbents such as activated carbon have excellent adsorption properties for a wide range of organic compounds, but require regeneration or disposal after saturation. UV-AOPs can be used for in situ or ex situ regeneration of adsorbents, or combined with adsorption to remove a wider range of pollutants.
Application Markets:
Advanced Drinking Water Treatment: Removal of trace organic pollutants (such as EDCs and pharmaceutical residues) to ensure water supply safety.
Municipal Wastewater Treatment Plant Upgrading: Targeting emerging pollutants in tailwater. Deep purification of wastewater (such as antibiotics and polypropylene glycol polycyclic aromatic hydrocarbons) to meet higher discharge standards or reclaimed water reuse requirements.
Industrial wastewater treatment: This includes standard treatment or pretreatment of wastewater from the pharmaceutical, chemical, pesticide, surfactant, and dye industries. Enviolet has over 800 UV advanced oxidation systems in operation worldwide, including over 60 engineering projects in China, including pharmaceutical and chemical industries (Enviolet Brochure - UV Advanced Oxidation Technology for Industrial Wastewater Treatment).
Groundwater and soil remediation: In-situ or ex-situ treatment of groundwater and leachate contaminated with POPs, petroleum hydrocarbons, and other substances.
High-concentration organic wastewater treatment: Treatment of landfill leachate, laboratory wastewater, and other wastewater.
Municipal Wastewater
Municipal water supply
Recycled Water Reuse
Township water supply and drainage
Industrial Park
New pollutant control
Water ecological restoration project
