Pharmaceutical Chemical Wastewater
Pharmaceutical chemical wastewater refers to the wastewater generated during the production processes of pharmaceuticals and chemicals. It is usually complex in composition, highly toxic, and difficult to degrade, posing a high level of treatment difficulty. Main characteristics: complex composition, high concentration of organic substances (high COD), high toxicity, high salinity, poor biodegradability (low BOD/COD), and large pH fluctuations.
Process Flow Example
Pharmaceutical Chemical Wastewater Treatment Process Flow Description
(1) Regulation tank: Wastewater first enters the regulation tank, mainly to homogenize water quality and quantity, reducing the load fluctuations of subsequent treatment units.
(2) Coagulation sedimentation tank: By adding coagulants, suspended solids and colloidal substances in the wastewater form flocculents, which are removed after precipitation.
(3) Homogenization tank: Further homogenizes water quality to ensure the stability of subsequent biological treatment.
(4) Crown advanced oxidation integrated equipment: Through Crown RIC-CAT advanced oxidation technology, the B/C value is improved, enhancing the biodegradability of the wastewater;
(5) Anaerobic reactor: May employ efficient anaerobic processes such as UASB or IC to treat high-concentration organic wastewater and produce biogas.
(6) A/A/O process (anaerobic/anoxic/aerobic):
Anaerobic section: Degradation of large molecular organic substances, improving the biodegradability of wastewater.
Anoxic section: Denitrification for nitrogen removal.
Aerobic section: Further oxidation of organic substances and completion of the nitrification reaction.
(7) Secondary sedimentation tank: Separates the activated sludge generated by the A/A/O process, with the supernatant entering subsequent treatment.
(8) Crown advanced oxidation integrated equipment: Ensures that the effluent water quality meets the discharge standards of the "Chemical Synthesis Pharmaceutical Industry Water Pollutants Discharge Standard" (GB 21904-2008), completely removing residual trace pollutants. Depending on the discharge index requirements, the Crown Ir-TiOx-HA advanced oxidation process may be adopted.
Core Advantages
Electro-catalytic Advanced Oxidation Process
Crown's electro-catalytic advanced oxidation process features two independently developed electrodes. The RIC-CAT is mainly used to improve the B/C ratio in chemical and pharmaceutical wastewater, enhancing its biodegradability; the IS-TiOx-HA has an ultra-high oxidation-reduction potential, specifically for removing refractory large molecular organic substances, ensuring stable and compliant drainage.
Ruthenium-iridium/carbon nanocomposite catalytic electrode (RIC-CAT)
(1) Efficient catalytic oxidation to increase B/C ratio
Direct electron transfer: The high oxygen evolution potential (>1.6V vs. SHE) of RuIr NPs inhibits side reactions, prioritizing the oxidation of organic substances (such as phenols, antibiotics), transforming large molecular refractory pollutants (BOD/COD < 0.3) into small molecular biodegradable substances (BOD/COD > 0.4).
In-situ generation of reactive oxygen species (ROS):
Anodic reaction: H2O → ⋅OH+mathrmH+++− (ruthenium-iridium catalysis reduces the overpotential for ⋅OH generation). Defect sites on the surface of activated carbon promote the adsorption and decomposition of H2O2 (→ 2·OH), enhancing the free radical chain reaction.
(2) Synchronous electroadsorption-catalysis synergy
Activated carbon physically adsorbs and enriches pollutants (such as hydrophobic organic substances), shortening their distance to RuIr active sites, accelerating interfacial catalytic reactions, and solving the problem of low mass transfer rates in traditional electrodes.
Iridium-doped sub-oxidized titanium composite heterostructure electrode (IS-TiOx-HA)
(1) High oxidation potential
Iridium inhibits oxygen evolution side reactions, making the electrode more prone to generating hydroxyl radicals (·OH), thereby enhancing the degradation efficiency of organic substances.
(2) Heterostructure can improve performance in the following ways
Enhanced oxidation potential: In the IrO2/Ti4O7 heterojunction, the high oxygen evolution potential of IrO2 inhibits water decomposition, making the electrode more inclined to generate strong oxidizing free radicals (such as ·OH).
Improved charge separation: The energy level difference between different materials can promote interfacial charge transfer (e.g., TiO2@Ti4O7 heterojunction), reducing electron-hole recombination and increasing catalytic efficiency.
