The disc stack separator is also called disc separator. It is a device that rapidly separates solid and liquid through high-speed centrifugal force. The alias is also called disc centrifuge or conical plate centrifuge, which belongs to a type of vertical centrifuge. The disc separator is driven by a motor and rotates at high speed. In the bowl of the disc separator, there is a set of disc-shaped parts nested with each other-commonly known as discs. There is a small gap among the discs, which are used for centrifugal sedimentation of materials. The suspension (or emulsion) to be processed enters the bowl of the disc separator through the feed pipe. When the suspension (or emulsion) flows through the gap between the discs, the solid particles (or droplets) settle on the disc under the action of the centrifuge to form a sediment (or liquid layer). The sludge slides along the surface of the disc to separate from the disc and accumulates in the inner bowl where the diameter is large, and the separated liquid is discharged from the bowl through the liquid outlet. For the 3-phase disc separator, there are two centripetal pumps inside, which can discharge the two immiscible liquid phases having difference densities. The role of the discs in the disc separator is to shorten the settling distance of solid particles (or droplets) and expand the effective settling area of the bowl so as to greatly improve the production capacity of the disc separator. The solids accumulated in the bowl can be discharged through the automatic slag discharge mechanism without stopping the machine. By using the disc separator, solid-liquid-liquid 3-phase separation or solid-liquid separation is realized.