As the core functional unit of riserless mud recovery system， the mud lifting centrifugal pump drives the mud stored in the suction module to carry rock cuttings recirculate back to the drilling platform through the return pipeline. Previous designs of the riserless mud recovery system primarily employed disc pumps as the lifting unit， with specific structural design and theoretical analysis conducted around them.However， there has been limited research on multi-stage centrifugal pumps， which offer superior hydraulic performance. In this study， we focus on the theoretical basis and specific parameters of a multi-stage centrifugal pump，and develop a computational model using CFD-DEM coupling calculation to conduct a full-scale flow field simulation.This simulation investigates the impeller design， flow field characteristics， internal particle distribution patterns， and mud rock transport patterns within the pump.The results validate the centrifugal pump’s good particle permeability under design conditions.Furthermore， we conducted hydraulic performance tests on a centrifugal pump prototype using a mud lifting test bench. The test resultsindicate that the pump exhibits satisfactory operational working characteristics and hydraulic performance， meeting the design requirements for application in deep-sea riserless drilling operations.