For the 80 tonnes of wastewater generated per day in biopharmaceutical plants, the key to achieving compliance is an effective treatment process. The sources of biopharmaceutical wastewater mainly include the discharge of organic matter in the production process, such as waste filtrate, waste mother liquor and recycled residual liquid, which are characterized by high concentration, small water volume and large pollutant content.
In addition, there are flushing effluents and ancillary process effluents such as cooling water, circulating water, and deionized wastewater, which also need to be treated due to low concentrations but large volumes.
There are two types of wastewater treatment: high concentration and low concentration.
The composition of high-concentration wastewater is complex, containing a large amount of organic matter, high toxicity, dark color and high salt content, and poor biochemical properties, which is continuous discharge and difficult to treat. The treatment process includes pre-treatment, biological treatment and advanced treatment.
1. Pre-treatment stage
The main purpose of the pretreatment phase is to remove large particulate matter from the wastewater, adjust the water quality, and prepare for the subsequent biological treatment phase. The specific steps include:
Grids: Large solids such as plastics, fibers, and metals are first removed from the wastewater through screens.
Conditioning Tank: Wastewater is introduced into the regulating tank to balance the wastewater flow and reduce the impact on subsequent treatment equipment. At the same time, conditioning tanks help to lower the pH of the wastewater, making it more suitable for biological treatment.
Sedimentation tank: After the conditioning tank, the wastewater enters the sedimentation tank, where suspended solids and some insoluble organic matter are removed by gravity.
If you like it, like, follow, favorite. Liyuan Environmental Protection will share more wastewater treatment cases and knowledge.
2. Advanced oxidation pretreatment
For highly concentrated wastewater, additional pretreatment steps, such as advanced oxidation, may be required to improve its biodegradability. Methods include:
Microelectrolysis: Metal electrodes are used to generate microcurrents to promote the oxidation and decomposition of organic matter.
Fenton oxidation: Fenton reagents (Fe^2+ and H2O2) are used to produce strong oxidants that effectively degrade a variety of organic pollutants.
Electrolytic treatment: The electrolysis process converts organic matter into small molecules to improve the biodegradability of wastewater.
Evaporative crystallization: Evaporation removes part of the water, concentrates the wastewater, and then crystallizes to remove soluble solids.
3. Biological treatment stage
Biological treatment is a core part of wastewater treatment, which mainly uses the metabolic activity of microorganisms to degrade organic matter. The main methods include:
Anaerobic treatment:
UASB (Upflow Anaerobic Sludge Bed): An efficient anaerobic treatment technology with the advantages of sludge granulation, good gas-solid-liquid separation effect, and strong treatment capacity.
Other anaerobic reactors, such as EGSB (Expanded Granular Sludge Bed) and IC (Internal Circulation Reactor), are suitable for the treatment of highly concentrated organic wastewater.
Aerobic treatment:
Aerobic biofilm reactors: such as biological contact oxidation ponds, which use microorganisms on biofilms to degrade organic matter.
Activated sludge method: oxygen is provided by aeration to enable microorganisms to degrade organic matter under aerobic conditions.
4. Advanced processing stage
Advanced treatment aims to further purify wastewater and remove hard-to-degrade organic matter and nutrients such as nitrogen and phosphorus. Common methods include:
Biofilm filtration: Microorganisms on the biofilm are used to remove residual organic matter.
Coagulation and sedimentation: A coagulant is used to aggregate suspended solids and colloidal particles into larger flocs, and then the precipitation is removed.
Membrane Bioreactor (MBR): Combines membrane separation technology and biological treatment to improve effluent quality.
Through this range of wastewater treatment processes, biopharmaceutical plants can effectively treat and purify wastewater, reduce environmental impact, and ensure compliance with local discharge regulations.