Disc stack centrifuge is also called 3-phase centrifuge unit. It is one of the major separation equipment for oily sludge separation.

In oily sludge separation system, there are normally at least 2 sets centrifuges. Firstly, a decanter centrifuge will remove the sand to reduce the solids contents in the liquids. Disc centrifuge will be used after 2-phase decanter centrifuge.

Why disc centrifuge should be used after decanter centrifuge?

The reason is that, in order to have better separation performance, the max. solids / soil content in the liquid entering into disc centrifuge is better to be controlled below 3%. So before feeding to 3-phase Disc centrifuge, the oily sludge liquid should be separated by 2-phase decanter centrifuge.

What is the difference of 2-phase decanter centrifuge and 3-phase disc centrifuge?

2-phase decanter centrifuge is used for liquid and solids separation. After the decanter centrifuge, the output is liquid mixture (oil & water mixture), and solids phase. While the disc centrifuge is used for 3 phase separation. After disc centrifuge, there will be 3 kinds of outputs: water, oil and solids.

What is the quality of the solids, recovered oil and water after decanter centrifuge and 3 phase disc centrifuge?

The oil content in the solids discharged from decanter centrifuge is between 2%-5% which can be sent to biodegradation or thermal unit for final disposal.

The oil/water mixture from decanter centrifuge will be separated again to get oil, water and soil. The recycled water recovered from disc centrifuge can be reused in the oily sludge washing process, or for dilution. The oil content in the recovered oil from disc centrifuge is around 500-1000PPM. It is clean enough to sell to the refinery company.

GN Solids Control is a leading manufacturer which can offer complete solution for oily sludge separation. Besides decanter centrifuge and disc centrifuge, GN Solids Control does also have other processing equipment for waste management and oil sludge separation, like inclined plate clarifier, oil/water separator, screw conveyor, high G drying shaker, vertical cuttings dryer, dewatering system…