Decanter and Separation Technology application in food process industry

In this article, we mainly discussed two kinds of separation technology: gravity separation and centrifugal separation. Based on it, decanter will be introduced accordingly.

I. Separation technology

Adopting the principle that the light liquid, heavy liquid and solid phase, with different density and mutually insoluble in the mixed liquid, it can be gained different sedimentation speed in the centrifugal force or gravity force. Separating stratification or causing the solid particles in the liquid to deposit can be achieved.In the gravity force field it is called gravity separation, while in the centrifugal force field it is called centrifugal separation.

1. Gravity separation

 On account of difference in density, the mixed liquid in the container, after a period of time, is gradually divided into 2 layers. The heavy phase particle of the mixed liquid deposits to the bottom of the container, while the light phase one suspends to the upper surface. A rather distinctive dividing plane forms between the light and heavy phases. The separation speed is affected by the difference in density between the light and heavy phases that make up the mixed liquid. The larger the difference in density is, the faster the separation speed will be.

2. Centrifugal separation

 When the container filled with mixed liquid rotates at high speed around its own axis, due to the difference in density between the two phases making up the mixed liquid, they bear different centrifugal force. Under the action of a larger centrifugal force, the heavy phase in the mixed liquid quickly subsides on the inner wall of the drum, while the light phase slowly adhere close to the surface of heavy phase. The faster the container rotates, the larger the difference in centrifugal force borne by the light and heavy phases that make up the mixed liquid, and the faster the separation speed. When the container is equipped with such parts as feeding device, propelling device and discharging device, the container is converted into a separator. Compared with gravity separation, it enjoys advantages such as high efficiency, fastness and continuousness.

II. Decanter

The decanter manufactured by our factory, with the drum diameter at different diameters, is mainly composed of drum, helical propeller, planet gear differential mechanism, pedestal, hood and lubricating system.

The decanter is driven by two motors. The main motor drives the drum and the housing of differential mechanism to rotate through belt, while the auxiliary motor drives through the belt pulley the input shaft of the differential mechanism to rotate, which, after speed change, drives the helical to rotate. In this way the drum and helical rotate in the same direction but with certain differential speed.

The decanter is used widely in food process, especially in liquid food separating industry, like juice, puree, beverage etc. As a main part of whole, decanter performs very well during separating process.It can be combined with other separating machines like filter, UF, disc centrifuges to get clarified juice.