Effective solids control can be attributed to the overall performance of all the components of the mud systems. Conditioning the drilling fluids with the goal of dramatically lowering maintenance cost, avoiding excessive chemical treatment and maintaining mud systems volume will decrease the chance of equipment failure, unnecessary mud expenses, hole and drilling problems.

In the early oil industry, open earthen pits were used as settling area to separate solids and mud, thereby acting as the solids control equipment. Now, with the stringent environmental regulations and high mud costs, the economics of an effective mud system come into consideration. Different solids control companies introduce zero-discharge systems, closed-loop systems, "quick move" technology, screening technology, disposal options, etc.

We use the below solids control equipment in drilling fluids purification usually, they are combined to a system called solids control system, and we usually have 5 stage equipment applied to the system, what are the functions of the 5-stage equipment in drilling? Let’s see together!

Shale Shaker: The shale shaker is the first stage solids control equipment in drilling purification system. It can remove cuttings above 75μm brought from the drilling well to leave the liquid with smaller particles into the tanks below, which will flow into next solids control equipment for further treatment.
 

Vacuum Degasser: Gases are entrained in drilling fluids from the wellbore during normal drilling operation as well as during “kick” or well control situations, these gases may bring safety hazards and create operational problems, in case of the presence of hazardous gases, it is desirable to localize the point where gas is released from the mud by installing a vacuum degasser.

Desander: Desander is the second stage of solids control equipment. It is mainly used to take away the solids with diameter ranging from 45 to 74μm from the formerly treated fluids and then send them to the next stage for more purification.

Desilter: Desilter is the third stage of solids control equipment. In this case, the solids with diameter ranging from 15 to 44μm are to be separated from the rest, which will go through further processing.

Mud Cleaner: Mud cleaner is the second or third stage separation equipment of drilling liquid, which will deal with the mud after being treated by the first grade separation equipment.

Decanter Centrifuge: Decanter centrifuge is used in separating suspension of solid phase with particle diameter d≥2μm for drilling mud and fluids handling.

Besides, we need other auxiliary solids control equipment, including mud tank, mud gun, mud agitator, pumps including submersible slurry pump, shear pump, centrifugal pump, also, we need to manage the waste of drilling, then we need some drilling waste management equipment, we usually use vertical centrifuge, screw conveyer, Hi-G dryer, screw pump.