Desander and Desilter Are Solid Control Equipment with a Set of Hydrocyclones That Separate Sand and Silt

Sep 04, 2013

Desanders and desilters are solids control equipment with a set of hydrocyclones that separate sand and silt from the drilling fluids in drilling rigs. Desanders are installed on top of the mud tank following the shale shaker and the degasser, 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 is 45~74μm, and 15~44μm for desilter.

A centrifugal pump is used to pump the drilling fluids from mud tank into the set of hydrocyclones.

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 of 10 inches ( 250 mm ) is able to remove 50% of solids within the 40-50μm range at a flow rate of 500 US gallons per minute ( 32 L/s ), while a desilter ( using 4 inches ( 100 mm ) cone) is able to remove 50% of solids within the 15-20μm range at a flow rate of 60 US gallons per minute ( 3. 8 L/s ). Micro-fine separators are able to remove 50% of solids within the 10-15μm range at a flow rate of 15 US gallons per minute ( 0. 95 L/s ). A desander is typically positioned next-to-last in the arrangement of solids control equipment, with a decanter centrifuge as the subsequent processing unit. Desanders are preceded by gas busters, gumbo removal equipment ( if utilized ), shale shaker, mud cleaner ( if utilized ) and a vacuum degasser. Desanders are widely used in oilfield drilling. It has been proved that hydrocyclone desander is a kind of economic and effective equipment.

 


desander
 


Desilter is the third step in the whole drilling fluids purification flow line, which is able to remove particles between 20-40μm in the drilling mud, making the fluid purer and ready for the next stage equipment and decreasing its workload.

Structure

Desilter is made up of polyurethane hydroclones and fine mesh vibrating screen. It mainly used to clean out harmful solids whose diameter are between 15-44μm in the drilling fluids. It is shown that the equipment has reasonable design, reliable work and well desilting effect, and is the ideal drilling fluids solids control equipment.

Also, desander, desilter and screen can be combined to be a mud cleaner. A mud is fed to the inlet of the hydrocyclone ( desander and/or desilter ) to separate particles and the underflow passes to the fine shaker screen mesh where particles larger than barite are discarded and thrown away. In most drilling operations, a mud cleaner is installed in its mud systems. It is usually located in a mud tank in the same location as with the desilters.