Desanders and Desilters Information
How to Select Desanders and Desilters
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Desanders and desilters are solids control equipment that is installed on top of a mud tank. Each piece of equipment consists of a set of hydrocyclones that separate sand and silt from drilling fluid while they differ by the size of the hydrocyclones used.
Desanders utilize several 8", 10", or 12" hydrocyclones. Utilizing hydrocyclones with larger internal diameters increases the flow rate as well as the size of the solids removed. Increasing the number of hydrocyclones in the package also increases the flow rate of drilling mud through the desander. Typically a 10 inch cone (hydrocyclone) is capable of removing 50% of solids with in the 40 to 50 micrometer range at a flow rate of 500 gallons per minute.
Desilters utilize smaller hydrocyclones and are used to process mud that has already been cycled through the desander. The number of cones in a desilter is greater than the corresponding desander as the smaller cones accommodate lower flow rates. Desilters are comprised of either 4" or 5" cones whereas each 4" cone is capable of removing 50% of solids 15 to 20 micrometers in range at a flow rate of 60 gallons per minute.
Desanders and desilters are used to remove solids from drilling fluid that a shale shaker is incapable of removing. Other solids control equipment that may be used upstream from desanders and desilters includes degassers, mud cleaners, and gumbo removal equipment. Typically a decanting centrifuge follows the desilter before the drilling fluid is pumped back down into the well.