AP200 desilters are capable of processing up to 240 stere per minute and can get do to cut point of approximately 35 microns. This equipment is designed to remove the sand and silt sized particles before they have a chance to break down even smaller.
Water as a drilling fluid does not qualify as a mud. If there are no hole (formation) problems that prevent its being the most economical drilling fluid; if neither the geologist, palentologist, nor production supervisor have valid objections; and if it is available, water is seldom if ever surpassed. When the formation requires, or a supervisor demands , filtrate control and / or viscosity and /or gels in the drilling fluid, a “mud” is built. Or if the fluid density required is too high for salt water alone , mud properties are required to suspend barites.
The overall efficiency of cuttings removal by the solids-control system, Es, can be expressed as:
Es = E1 f 1 +( 1 – E1 )E2 f 2 + ( 1 – E2 )E3 f 3 +( 1 – E3 )E4 f 4 (1)