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, hydro ...

s that separate

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

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 (chemistry), suspension with water. Silt usually ...

from the drilling fluids in

drilling rigs A drilling rig is an integrated system that Drilling, drills wells, such as oil or water wells, or holes for piling and other construction purposes, into the earth's subsurface. Drilling rigs can be massive structures housing equipment used to ...

. Desanders are installed on top of the mud tank following the shale shaker 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 i ...

, but before the desilter. The desander removes the abrasive solids from the drilling fluids which cannot be removed by shakers. Normally, the solid diameters for desanders to separate would be 45~74μm, and 15~44μm for desilters. A

centrifugal pump Centrifugal pumps are used to transport fluids by the Energy transformation, 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 ...

is used to pump the drilling fluids from the 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 40-50μm range at a flow rate of , while a desilter with a cone is able to remove 50% of solids within the 15-20μm range at a flow rate of . Micro-fine separators are able to remove 50% of solids within the 10-15μm range at a flow rate of . A desander is typically positioned next-to-last in the arrangement of solids control equipment, with a desander

centrifuge A centrifuge is a device that uses centrifugal force to subject a specimen to a specified constant force - for example, to separate various components of a fluid. This is achieved by spinning the fluid at high speed within a container, thereby ...

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