Project Background and Challenges: 

A biotechnology company needs to extract high-purity active ingredients from plant raw materials. The extraction process requires the use of organic solvents such as ethyl acetate and dichloromethane, and involves multiple countercurrent extractions under gentle stirring. The process demands that the equipment possess excellent solvent corrosion resistance, be absolutely free of metal ion contamination to ensure product purity, and facilitate easy visualization of the extraction process.

Solution – PVC Rigid Panel Extraction Tank Unit:

1. Modular Transparent Design: A total of 6-stage, series-connected square extraction tank units are constructed using transparent PVC rigid panels as the main material. Each tank measures 1.5m × 1.5m × 1.8m, with a panel thickness of 15mm. The transparent material allows operators to clearly observe the interface position, dispersion state, and color changes of the two-phase liquid (aqueous and organic phases), facilitating precise control.

2. Refined Internal Component Integration: The tank is equipped with multi-stage baffles precisely cut and welded from PVC panels, guiding the liquid in a zigzag flow, extending the mass transfer path. The mixing system utilizes PVC-coated stirring shafts and blades with stepless speed adjustment, ensuring thorough mixing of the two phases without over-emulsification. The tanks are connected via PVC pipes and solvent-resistant diaphragm pumps, forming a continuous countercurrent extraction system.

3. Operational Results: This PVC extraction tank system completely eliminates the risks of catalytic side reactions and product contamination that can occur with metal equipment. During two years of production operation, the extraction rate of the target product increased by approximately 5%, and the content of key metal impurities in the product decreased to the ppb (parts per billion) level, meeting the stringent requirements of the high-end pharmaceutical market. The equipment's transparency also makes process debugging and employee training more intuitive and efficient.