Sedimentation centrifuge is the only can remove free from the separation of the surface of the solid phase particles of liquid solid-liquid separation device.
1, the structure of the centrifuge
Sedimentation centrifuge is also called spiral centrifuge, referred to as "centrifuge, its structure as shown.
2, centrifugal settling of solid phase particles
The separation of solid phase particles in the centrifuge is conducted in centrifugal field. Due to high-speed rotating drum, drilling fluid in the liquid phase and solid phase have a lot of centrifugal force, the difference between the liquid and solid two-phase centrifugal force are effective centrifugal force acting on the particles, namely the centrifugal sedimentation force, this force makes the solid and liquid separation.
Particles in centrifugal field, the centrifugal force to overcome the resistance to movement subsidence, which can be derived:
This is the centrifugal settling velocity of particles in centrifugal field. Type of w2r for centrifugal acceleration. Due to the high speed centrifuge rotation, the gravity settling velocity of particles in the centrifuge is less than the centrifugal sedimentation velocity, so in general, only consider the centrifugal sedimentation in the centrifuge.
Centrifugal acceleration and acceleration of gravity of the ratio of dimensionless called centrifuge separation factors, namely
This is a condition of measure centrifuge separation ability.
3, the use of the centrifuge
1) centrifuge can be used to deal with increasing drilling fluid recycling barite, when using the system part of drilling fluid by centrifuge in processing; Flow will be at the end of the recycling of solid phased particles, and the overflow of liquids (including low density solid phase) discarded.
(2) the centrifuge can be used to deal with the increasing drilling fluid, recycling liquid, remove tiny low density of the solid phase particles.
(3) to improve the separation efficiency of centrifuges, centrifuge must control input of the drilling fluid viscosity, so generally more water sparse, keep the viscosity in the range of 35 ~ 37 s funnel viscosity. The addition of dilution water velocity is generally 0.38 ~ 0.50 L/s.
(4) to ensure that the centrifuge work effectively, the input speed of drilling fluid should not exceed the recommended range, and don't overload the centrifuge. The recommendation of drilling fluid input speed as shown in the table.
(5) centrifuge when handling of the drilling fluid is recycled, generally should set some time drilling fluid added bentonite, if not timely supplement, can make the drilling fluid viscosity, fluid loss to increase.