There are many solid-control methods

The solid phase of drilling fluid can be divided into two kinds, one is harmful solid phase, the other is useful solid phase. The so-called drilling fluid solid phase is to clear up the harmful solid phase, maintain the useful one, to meet the requirement of drilling fluid technology performance. Generally, the drilling fluid solid phase control is short named as solid-control.

There are many solid-control methods, the below four is common used:

The first is dilution method, it is use the water or other clean fluid to dilute the drilling fluid.

The second is Replacement Method, it is a new drilling fluid of clear water or other fluid required, to replaced a high solid content of drilling fluid, in this way to lower the low solid content.

The third is mechanical issue. It is divided the solid phase of solid-control through the shale shaker, desander, desilter, mud cleaner, centrifuge and other mechanical equipment, on the principal of screening centrifugal separation, according the requirement to decide use, to achieve the goal of controlling drilling fluid solid phase.

Different device has different separation capacity, so for different use. This is a better method, and a low cost, is frequently used method.

The handle capacity of the common used machinery and equipment：

Shale shaker: above 74 microns

Desander: 25---40 microns

Desilter: 10---25 microns

Centrifuge: less than 10 microns

The fourth method is chemical process, it is use the non-dispersive mud system to control drilling cuttings, to make sure it not disperse or cohesion, conducive to the mechanical or chemical sink. This method is supplement of mechanical way to clear up solid phase, complement each other.