GNLW363 centrifuge is the most common model for dewatering unit. It is equivalent model to Derrick DE-1000 and Swaco 518. 
There are chemicals for biosolids for the fluids phase from drilling mud.The fluids phase will be flocculated by chemicals before going into centrifuge.The very fine solids will be thickening to bigger size that centrifuge can treat. Then clean water available.