Project Overview
- Located in Fenghuangyuan Industrial Park, Lengshuitan, Yongzhou, the company specializes in three major series of natural essential oils—litsea cubeba oil, natural citral, and citronella oil—comprising over 20 products. The company's products hold international certifications including FDA and EU REACH, and are exported to more than ten countries across Europe, the Americas, and Southeast Asia, with an annual processing capacity exceeding 1,500 tons of essential oils.
- The project is designed with a wastewater treatment capacity of 32 m³/d, with equipment installation and commissioning now completed.
Key Technical Challenges
- The wastewater contains natural essential oils, terpenes, organic acids, and residual organics from extraction processes, exhibiting significant fluctuations in COD, color intensity, and odors. Some aromatic components are bacteriostatic, resulting in poor biodegradability.
- Distillation residues and high-strength extraction wastewater contain extremely high pollutant concentrations, requiring strict source-segregation and separate pretreatment to prevent shock loading of the biological system that could lead to non-compliant effluent.
Process Flow
- Production wastewater: Production wastewater → Manual Bar Screen → Production Wastewater Collection Tank → Oil-Water Separator → DAF System → pH Adjustment Tank → Iron-Carbon Micro-Electrolysis → Neutralization & Sedimentation Tank → Biochemical Feed Tank
- Other low-concentration wastewater: Other low-concentration wastewater → Biochemical Feed Tank
- Combined wastewater: Biochemical Feed Tank → High-Efficiency Anaerobic Reactor → A/O Tank → MBR Tank → Ozone Oxidation Tank → Clear Water Tank → Industrial Park WWTP