News Center

The oil leaching process is an oil-making method that uses the principle of extraction, selects a certain organic solvent that can dissolve grease, and contacts the oil (soaking or spraying) to extract the grease in the oil.

Principle of leaching oil process:

Leaching, also known as "extraction", is the process of using organic solvents to extract oil from oil. The process of leaching oil can be regarded as solid-liquid extraction. It is a process that uses solvents to have different solubility properties for different substances to separate relevant components in solid materials. During leaching, the oil is treated with a solvent, and the easily soluble components (mainly grease) are dissolved in the solvent. When the oil is leached in a static state, the oil is transferred in the form of molecules, which is a "molecular diffusion". However, the leaching process is mostly carried out with relative movement between the solvent and the pellets. Therefore, in addition to molecular diffusion, there is also a "convection diffusion" process that depends on the flow of the solvent.

Classification of leaching oil process:

1. According to the operation mode, the leaching oil process can be divided into batch leaching and continuous leaching.

(1) Intermittent leaching

The intermittent leaching material embryo enters the extractor, the meal is discharged from the extractor, the injection of fresh solvent and the extraction of concentrated mixed oil are all batch, intermittent, and periodic leaching processes that belong to this type of batch leaching. Oil process type.

(2) Continuous leaching

The continuous leaching material embryo enters the extractor, the meal is discharged from the extractor, the injection of fresh solvent and the extraction of concentrated mixed oil are all continuous leaching processes that belong to this type of continuous leaching oil process.

2. According to the contact method, the leaching oil process can be divided into immersion leaching, spray leaching and mixed leaching.

(1) Immersion leaching

The material embryo is soaked in a solvent to complete the leaching process is called immersion leaching. The immersion-type leaching equipment includes a tank type, in addition to bow-type, U-type and Y-type extractors.

(2) Spray leaching

The solvent is in the spray state and contacts the embryo to complete the leaching process, which is called spray leaching. The spray leaching equipment includes crawler leaching equipment.

(3) Hybrid leaching

This is a leaching method that combines spraying and soaking. The hybrid leaching equipment includes a flat-rotating leaching device and an annular leaching device.

3. According to the production method, the oil extraction process can be divided into direct extraction and pre-expression extraction.

(1) Direct leaching

Direct leaching is also called "one-time leaching". The leaching oil process is to directly carry out the leaching oil production process after the oil is pretreated. The direct leaching process is suitable for processing oils with lower oil content.

(2) Pre-expression extraction

The pre-extruded leaching oil is pre-extruded to remove part of the oil, and then the cake with higher oil content is subjected to the process of leaching the oil. This process is suitable for oils with higher oil content.

Whether the leaching production can proceed smoothly is closely related to the selected leaching oil process, which directly affects the product quality, production cost, production capacity and operating conditions of the edible oil plant after it is put into production. Therefore, an excellent and reasonable leaching oil process flow should be adopted.