Before understanding the working of decanter centrifuge, we should firstly know what exactly the centrifuge is. Decanter centrifuge is used to extract solids from liquids when they are mixed together. Almost in every industry, there is need to separate solid from the liquids, so decanter centrifuge has become quite essential. And in oil industry, chemical industry, food processing industry and water treatment plants industry, it has become the basic thing without which these industries cannot run. There are several kinds of decanter centrifuges, such as: vertical, horizontal, or scroll (conveyor). Decanter centrifuge works basically on the gravitational separation process theory. If you take a glass of water mixed with mud or any solid material, and put it on some place without moving it, you will notice after some time that mud will settle down at the bottom and water is separated in the upper area of the glass and liquid and solid is separated. How does that happened? The principle behind is gravitational force which leads to separation of solid from liquid. Decanter centrifuge works on the same principle. And higher gravitational forces are produced by continuous rotation to separate the solids from liquid. Decanter centrifuge speeds up the process of separation by increasing the force of gravity by 1000 to 4000 times. The result is the process that used to take hours now can be done in seconds with the help of decanter centrifuge.

Solids control is a technique used in drilling rig to separate the solids in the drilling fluids that are crushed by the drill bits and carried out of the well surface. Normally solids control system is consisted of five stages, including shale shaker, vacuum degasser, desander, desilter, centrifuge. Shale shaker is used to separate the big solids with diameter above 75μm, and 45~74μm for desander, and 15~44μm for desilter. Sometimes desander & desilter are combined as high efficient mud cleaner. When air enters into the drilling fluids, vacuum degasser is used to separate the air. If no air is found in the mud, the degasser will work as a big agitator. All these equipment are mounted on the top of the mud tank. After separating the solids, the clean mud will be pumped into the borehole again.
 

Drilling mud decanter centrifuges are designed specifically to remove unwanted solids and fine particles from virtually all kinds of used drilling mud, including those based on water/synthetics and conventional oil-based drilling fluids.

The Working Steps of Drilling Fluid Centrifuge

Step 1: The slurry is inserted into the centrifuge through a connecting pipe and onto a conveyor.

Step 2: Utilizing an internal feed compartment, the conveyor ushers the slurry through a nozzle into the bowl area.

Step 3: The bowl rotates at high speeds to induce gravitational forces.

Step 4: High speed rotation separates the solid material from the liquid in a matter of seconds.

Step 5: The conveyor delivers the solid material upwards where it is discharged through a nozzle.

Step 6: The solid material is removed, the purified liquid is released from a separate output.