The percolation method is a method of leaching in which a leaching solvent is continuously added to the crude powder of medicinal materials to allow the leaching solution to permeate through the medicine and flow out from the lower outlet. During percolation, the solvent infiltrates into the cells of the medicinal material and dissolves a large amount of soluble substances. As the concentration increases and the density increases, it moves downwards. The upper layer of leaching solvent or dilute leaching solution replaces the position, creating a good concentration difference and allowing diffusion to occur naturally. Therefore, the leaching effect is better than the leaching method, and the extraction is more complete, saving the operation time of separating the leaching solution. Continuous addition of new solvent from the top of the tank and continuous discharge of percolate extract from the bottom belong to dynamic extraction equipment.

Due to the complete extraction of active ingredients and the ability to directly collect percolate without filtration, it is widely used for the extraction of valuable medicinal materials, toxic medicinal materials, high concentration preparations, and medicinal materials with low active ingredient content.

This equipment mainly consists of a cylinder, a cone, an elliptical head (or flat cover), a spray pipe, a pneumatic slag gate, a pneumatic operation platform, etc. It has the characteristics of uniform solvent distribution and convenient slag removal. The solvent is evenly sprayed onto the medicinal herbs through the spray pipe on the upper part of the tank. Dissolve the active ingredients of medicinal herbs into a solvent through soaking. 

1. The slag door adopts ordinary double-cylinder opening and closing type or three-cylinder rotating type. The rotary safety door adopts single cylinder opening and closing, double cylinder rotating drive locking, incline wedge self-locking, which completely solves the leakage or decoupling accident caused by the instability of the compressed air source pressure, and the use of high safety factor.

2. It is equipped with medicine pressing device to prevent medicine from floating and medicine contamination.

This equipment is suitable for percolation operations in industries such as traditional Chinese medicine, plants, animals, food, and chemicals. Except for non organic medicinal herbs such as frankincense, rosin, and aloe vera, which soften into clumps when in contact with solvents and block the pores, making it difficult for solvents to pass evenly through the herbs, percolation is not suitable. Other medicinal herbs can be soaked using this method.