Functions of centrifuges for mud cleaning2013-05-02
The centrifugal separation is aimed at separating solid from drilling fluid, or separate two kinds of miscible liquids which are incompatible and different density.
Centrifuges are used to remove very fine solid particles (small down to 10 or 7µm). Since these fine particles affect mud rheological parameters in a much greater degree than the coarser particles therefore centrifuges can effectively control mud rheological properties and penetration rate in a favorable range by removing extra-fine particles.
Besides this function, centrifuges are also applied for recovering barite while discarding fine particles from weighted mud.
The primary purpose of centrifuge for weighted drilling fluid is control the viscosity. Because the drilling speed is slower under the situation of high viscosity. The method of control viscosity is separate out the superfine particles and colloid to waste pond, and the underflow which contains plenty of barite will be returned to drilling fluid cycle tank.
If we don’t use the centrifuge, we have to discard all of the drilling fluid for reducing the superfine particle density, even if the drilling fluid contain a large number of valuable weighted solid phase.