The decanter three-phase separator is the core equipment in the solidification treatment of water-based mud . It separates the solid and liquid (oil and water) in the water-based mud drilling fluid, especially the oil and water. The centrifuge in the solid control system, referred to as drilling fluid centrifuge, is also a key device. It is responsible for further processing the mud drilling fluid processed by the desilter. It is a 2-phase centrifuge, which is used to separate liquid (water) and solid (solid phase particles and colloid) in drilling fluid mud.
The centrifuge used in water-based mud treatment and the centrifuge used in the solid control system are composed of two rotors, one is called a drum, and the other is a spiral unloader (spiral). When the drum rotates at high speed, the drum The inner slurry rotates with the drum and is subject to centrifugal force. This centrifugal force is many times greater than gravity. In this way, solid particles are separated from the liquid and settled on the inner wall of the drum from the axis of the drum. The screw unloader inside the drum rotates at a lower speed than the drum and pushes the deposited solid particles to the slag outlet. The differential speed between the outer drum and the screw unloader depends on the transmission ratio of the differential and its speed. . The clear liquids with different two-phase densities form concentric cylinders, with the lighter liquid phase (oil) in the inner layer and the heavier liquid phase (water) in the outer layer, which are discharged through the light and heavy phase outlets, respectively.
The principle of solid-liquid separation is not difficult to understand. The key is the separation of two liquid phases, that is, the separation of oil and water. The large end plate of the spiral is equivalent to the oil-water two-phase phase converter. It converts the water in the inner and outer circles of the spiral to the inner ring, and converts the oil located in the inner circle of the spiral to the outer ring. Drain the oil tank through the oil outlet at the bottom of the centrifuge.
Water outlet principle of centripetal pump:
Water is drained into the pump cavity outside the large end cover. As shown in the figure above, the pump cavity is the cavity in the spiral large end cover and the large rear cover. It rotates at high speed and passes through the ribs on the end cover, which is equivalent to the impeller. Turn the water to rotate, and the rotating water will enter the centrifugal pump with pressure.