In the chemical, pharmaceutical, and pesticide industries, the treatment of high-salinity wastewater has long been a persistent challenge. The presence of organic contaminants in such wastewater not only lowers the purity of salt crystallization products—making resource recovery difficult—but also puts companies under continuous pressure to meet environmental compliance standards. How can organic compounds be efficiently removed from high-salinity wastewater while recovering both salts and valuable substances? The CWL-M series centrifugal extractor from Zhengzhou Tiei Extraction offer a reliable technical solution to this industry pain point, thanks to their outstanding liquid–liquid extraction and separation performance.

Challenges in Treating High-Salinity Wastewater: Emulsification, Fluctuation, Low Purity

Industrial high-salinity wastewater typically contains salt concentrations of 5%–20% and exhibits large fluctuations in COD levels. It often carries a variety of organic pollutants, such as phenols, alcohols, and aromatic compounds. Traditional treatment methods frequently encounter issues such as two-phase emulsification, difficult separation, and extraction agent loss, which ultimately lead to:
Low purity of crystallized salt, preventing reuse as industrial raw material.
Difficulty in maintaining stable compliance for wastewater discharge.
High operational costs and significant consumption of extraction agents.

CWL-M Centrifugal Extractor: Core Process Flow

To address the complex characteristics of high-salinity wastewater, the CWL-M series centrifugal extractor employs a multi-stage countercurrent extraction process, achieving both efficient removal of organic compounds and simultaneous enrichment in the extract phase. The process flow is as follows:

1.Wastewater Pre-treatment: Adjust the pH of high-salinity wastewater and remove suspended solids.
2.Extraction Mixing: Wastewater and the extraction agent are fed into the CWL-M centrifugal extractor in a precise ratio. In the high-speed centrifugal field, micron-sized droplets are thoroughly mixed, resulting in extremely high mass transfer efficiency.
3.Centrifugal Separation: The mixture separates instantly in the drum under strong centrifugal force. The heavy phase (high-salinity wastewater) and light phase (extraction agent loaded with organic compounds) are clearly separated, with no emulsification or entrainment.
4.Extraction Agent Regeneration: The loaded extraction agent enters a stripping unit to recover organic solutes for reuse.
5.Deep Treatment of High-Salinity Wastewater: The organic-free high-salinity water enters an evaporation and crystallization system to produce high-purity industrial salt, enabling resource recovery.

By combining 2–5 stages of countercurrent extraction, a COD removal efficiency of over 90% can be achieved.

Core Advantages of the CWL-M Centrifugal Extractor

1.Efficient and Rapid Separation, Complete Emulsion Suppression
The CWL-M centrifugal extractor uses centrifugal force to achieve rapid two-phase separation. Compared with traditional mixer settlers, it completely solves the common issue of emulsification in high-salinity wastewater and significantly reduces extraction agent entrainment and loss.
2.Corrosion-Resistant Design for Long-Term Stable Operation in High-Salinity Media
Key wetted components are made from corrosion-resistant materials such as Hastelloy, titanium, and polymer composites. This ensures reliable operation under harsh conditions with high chloride concentrations and fluctuating pH, extending equipment lifespan while reducing maintenance costs.
3.Low Energy Consumption with Outstanding Economic Efficiency
The CWL-M centrifugal extractor operates with a single-unit power of only 1.5–11 kw while providing high processing capacity. Its electricity consumption per ton of treated water is far lower than that of traditional extraction columns and mixer settlers. A fully enclosed structure prevents solvent evaporation, further reducing material losses.
4.Continuous Automation, Adaptable to Fluctuating Loads
The CWL-M centrifugal extractor can operate continuously 24/7 with PLC-controlled flow, rotor speed, and heavy phase parameters. It adapts effectively to large fluctuations in COD and salinity of incoming wastewater, minimizing the need for manual intervention.
5.Efficient Extraction Agent Recovery with Closed-Loop Operation
The extraction agent can be regenerated and reused after stripping, with solvent loss below 0.5%. Enriched organic components (such as phenols and aromatics) can be recovered as by-products or fuels, generating additional economic value.
6.Modular Design with Flexible Configuration
Each CWL-M centrifugal extractor can handle 0.5–50 m³/h. Multi-stage countercurrent, crossflow, or fractional extraction processes can be flexibly configured based on wastewater characteristics. The compact footprint allows easy expansion and scaling.

Application Case

A large pesticide manufacturer produces high-salinity wastewater with a salt content of 12% and a COD of approximately 8,000 mg/L, mainly containing aromatic compounds and phenols. After treatment with the CWL-M centrifugal extractors three-stage countercurrent extraction process:

The effluent COD was reduced to below 120 mg/L, surpassing the national direct discharge standard.
The extraction agent achieved a recycling rate of 98%.
The purity of evaporated crystallized salt increased from less than 75% to 96%, successfully sold as industrial by-product salt.
Overall annual operating costs were reduced by 40%, with a payback period of less than one year.

Zhengzhou Tiei Extraction Technology Co., Ltd. has been dedicated to liquid–liquid extraction equipment for over a decade. The CWL-M series centrifugal extractor has been successfully applied in fine chemicals, hydrometallurgy, pharmaceuticals, and environmental protection projects.
Email: sales@tieiextraction.com
Whatsapp: +86 19069612820