Desanders and desilters are solid control equipment with a set of

hydrocyclone Hydrocyclones are a type of cyclonic separators that separate product phases mainly on basis of differences in gravity with aqueous solutions as the primary feed fluid. As opposed to dry or dust cyclones, which separate solids from gasses, hydroc ...

s that separate

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a soil texture, textur ...

and

silt Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension with water. Silt usually has a floury feel wh ...

from the drilling fluids in drilling rigs. Desanders are installed on top of the mud tank following the

shale shaker Shale shakers are components of drilling Drilling is a cutting process where a drill bit is spun to cut a hole of circular cross-section in solid materials. The drill bit is usually a rotary cutting tool, often multi-point. The bit is pre ...

and the

degasser A degasser is a device used in the upstream oil industry to remove dissolved and entrained gases from a liquid. In drilling it is used to remove gasses from drilling fluid which could otherwise form bubbles. In a produced water treatment plant it ...

, but before the desilter. Desander removes the abrasive solids from the drilling fluids which cannot be removed by shakers. Normally the solids diameter for desander to be separated would be 45~74μm, and 15~44μm for desilter. A

centrifugal pump Centrifugal pumps are used to transport fluids by the conversion of rotational kinetic energy to the hydrodynamic energy of the fluid flow. The rotational energy typically comes from an engine or electric motor. They are a sub-class of dynamic ...

is used to pump the drilling fluids from mud tank into the set of

Solids control

Desanders have no moving parts. The larger the internal diameter of the desander is, the greater the amount of drilling fluids it is able to process and the larger the size of the solids removed. A desander with a ( cone) is able to remove 50% of solids within the 40-50 μm (micrometre) range at a flow rate of , whilea desilter ( Cone) is able to remove 50% of solids within the 15-20 μm range at a flow rate of . Micro-fine separators are able to remove 50% of solids within the 10-15 μm range at a flow rate of . A desander is typically positioned next-to-last in the arrangement of

solids control Solids control is a process used in drilling rigs which use drilling fluid. It involves separating the "cuttings" (drilled material) from the fluid, allowing it to be recirculated or discharged to the environment. Background Drilling rigs are d ...

equipment, with a desander

centrifuge A centrifuge is a device that uses centrifugal force to separate various components of a fluid. This is achieved by spinning the fluid at high speed within a container, thereby separating fluids of different densities (e.g. cream from milk) or ...

as the subsequent processing unit. Desanders are preceded by gas busters, gumbo removal equipment (if utilized),

, mud cleaner (if utilized) and a vacuum degasser. Desanders are widely used in oilfield drilling. Practice has proved that

desanders are economic and effective equipment.

References

Oilfield terminology Drilling technology Petroleum engineering {{Petroleum-stub

Solids control

See also

References