Energy　recovery　device　(ERD)　is　a　critical　component　in　seawater　reverse　osmosis　(SWRO)　desalination　systems,　which　recovers　hydraulic　energy　from　the　high-pressure　brine　and　effectively　reduces　system　energy　consumption.　In　this　thesis,　a　novel　integrated　seawater　desalination　pump-motor　energy　recovery　device　(ISPM-ERD)　without　the　slipper/swashplate　interface　is　proposed　to　further　reduce　energy　consumption　and　improve　system　integration,　which　is　able　of　concomitantly　achieving　seawater　pressurization　and　energy　recovery.　A　co-simulation　multibody　dynamic　model　with　rigid-flexible　coupling　is　applied　to　precisely　examine　the　internal　power　loss　of　ISPM-ERD,　especially　volumetric　loss　and　mechanical　loss　of　the　key　lubricating　interface.　Besides,　the　influence　of　shaft　rotational　speed　and　working　pressure　on　the　power　loss　and　overall　efficiency　of　ISPM-ERD　are　comparatively　investigated.　In　addition,　a　performance　study　of　the　presented　ISPM-ERD　is　carried　out　based　on　the　co-simulation　model,　which　reveals　the　energy　recovery　efficiency　and　specific　energy　consumption　(SEC)　of　ISPM-ERD　under　various　operating　conditions.　The　results　indicate　that　the　proposed　ISPM-ERD　is　sufficient　to　meet　the　needs　of　the　small-scale　SWRO　systems,　whose　energy　recovery　efficiency　is　more　than　90.1　%　in　the　3.0-7.0　MPa　operating　pressure　range　and　the　SEC　of　freshwater　production　is　2.94　kW　center　dot　h/m(3)　under　rated　working　conditions.