In the pharmaceutical and chemical industries, dimethyl sulfoxide (DMSO) is widely used as an excellent polar solvent. However, its wastewater is characterized by high COD, high salinity, and poor biodegradability, making it a persistent challenge in environmental treatment. How can DMSO be recovered economically and efficiently while ensuring compliant wastewater discharge? Extraction–distillation technology, with its high separation efficiency and low energy consumption, has become the mainstream solution in the industry. Amid this wave of technological upgrading, the CWL-M series centrifugal extractor, independently developed by Zhengzhou Tiei Extraction, is setting a new benchmark in DMSO wastewater treatment with its outstanding performance in multistage continuous counter-current extraction.
Dimethyl Sulfoxide Wastewater: Challenges and Opportunities
DMSO wastewater typically originates from processes such as pharmaceutical intermediate synthesis, aromatic extraction, and fiber spinning. It is characterized by:
High concentration: DMSO content can reach 10%–30%. Direct discharge not only pollutes the environment but also results in resource waste.
High boiling point: DMSO boils at 189°C, making simple distillation energy-intensive.
Thermal sensitivity: At high temperatures, DMSO tends to decompose and produce malodorous by-products.
The combined extraction-distillation process is key to solving this challenge: first, DMSO is selectively separated from the wastewater using an extractant; the enriched phase is then purified via distillation to recover DMSO, while the raffinate phase is discharged up to standard. The efficiency of the extraction step directly determines the overall economics of the system.
CWL-M Centrifugal Extractor: An Ideal Solution for Multistage Continuous Countercurrent Extraction
Leveraging over a decade of experience in liquid-liquid extraction, Zhengzhou Tiei Extraction has developed the CWL-M series centrifugal extractor, specifically designed for challenging systems such as DMSO wastewater. The equipment offers the following core advantages:
1.Multistage Continuous Countercurrent Flow, Extraction Efficiency Increased by Over 30%
The CWL-M centrifugal extractor features an integrated stage-wise mixing and separation structure, enabling continuous countercurrent extraction through multiple units connected in series. Compared with traditional mixer-settlers or rotary disc contactors, it offers a wider applicable range of phase ratios (O/A) and achieves a theoretical stage utilization rate of over 95%. In DMSO wastewater treatment, only 3–5 countercurrent stages are required to raise the DMSO extraction rate to over 99%, significantly reducing extractant consumption.
2.Sealed Operation, Zero VOCs Emission
Volatile solvents such as dichloromethane and ethyl acetate are often used in the DMSO extraction process. The CWL-M centrifugal extractor features a fully sealed design, combined with mechanical seals and nitrogen protection, completely eliminating solvent volatilization. This not only ensures operator safety but also meets increasingly stringent environmental inspection requirements.
3.Precise Control, Adaptable to Complex Operating Conditions
In response to the strong polarity and high viscosity that DMSO wastewater may exhibit, the CWL-M centrifugal extractor is equipped with variable frequency speed regulation and online turbidity monitoring. Operators can adjust parameters such as rotational speed and backpressure in real time according to material variations, ensuring long-term stable operation.
4.Modular Design, Reduced Investment and Maintenance Costs
The centrifugal extractor adopts a unit modular assembly approach, enabling on-site installation and immediate use without the need for extensive civil construction. Compared to traditional distillation pretreatment processes, the CWL-M centrifugal extractor system reduces floor space by 60%, lowers solvent consumption by 40%, and cuts overall operating costs by more than 35%.
Customer Case: From “Environmental Burden” to “Profit Engine”
A large pharmaceutical enterprise generates 5,000 tons of DMSO wastewater annually. Previously, it adopted a single-stage extraction+distillation process, achieving a DMSO recovery rate of only 85%, with significant extractant loss. After introducing Zhengzhou Tiei Extraction’s CWL-M centrifugal extractor four-stage counter-current extraction unit:
The single-stage DMSO extraction efficiency increased from 72% to 93%, and the overall recovery rate reached 99.2% after four stages in series;
Extractant consumption decreased by 42%, saving over RMB 800,000 in solvent costs annually;
Wastewater COD was reduced from 150,000 mg/L to below 3,000 mg/L, significantly easing the burden on subsequent biological treatment.
According to the company’s technical director: “The CWL-M centrifugal extractor not only helped us overcome environmental challenges, but also turned DMSO recovery into a new source of profit growth.”
DMSO wastewater treatment is no longer merely a matter of regulatory compliance; it has become a strategic lever for cost reduction and efficiency enhancement. With fewer stages, lower solvent loss, and more stable operation, Zhengzhou Tiei Extraction’s CWL-M centrifugal extractor maximizes the performance of the extraction–distillation process.
If you are facing challenges in DMSO wastewater treatment or seeking to upgrade your existing extraction process, please feel free to contact Zhengzhou Tiei Extraction.
Email: sales@tieiextraction.com
Whatsapp: +86 19069612820
