A support structure removal system (10; 110, 210; 410) comprising: a plurality of vessels (18; 118; 218; 418), each vessel comprising: a vessel body (40; 140; 440) having a top opening (44; 144; 444), the vessel body (40; 140; 440) being configured to retain an aqueous fluid (26; 126; 226; 426); and a porous floor (52; 152; 452) secured to and supported by the vessel body (40; 140; 440), wherein the porous floor (52; 152; 452) is configured to retain a three-dimensional part (14; 114; 414) and an attached support structure (15; 115; 415) built with an additive manufacturing system and inserted through the top opening (44; 144; 444); a plurality of impellers (60; 160; 460); and a second component (16; 116; 216; 516) comprising: a surface (22; 122; 520) configured to operably receive the plurality of vessels (18; 118; 218; 418), such that one of the plurality of impellers (60; 160; 460) is rotatably mounted below the porous floor (52; 152; 452) of each of the plurality of vessels; and a plurality of rotation-inducing assemblies (48; 148; 248; 448), each rotation-inducing assembly located below the surface (22; 122; 520), and each one of the plurality of rotation-inducing assemblies (48; 148; 248; 448) being configured to rotate one of the plurality of impellers (60; 160; 460) with magnetic fields when one of the plurality of vessels (18; 118; 218; 418) is received on the surface (22; 122; 520) of the second component (16; 116; 216; 516) to agitate and direct flows of the aqueous fluid (26; 126; 226; 426) through the porous floor (52; 152; 452), thereby dissolving at least a portion of the attached support structure (15; 115; 415) to separate the support structure from the three-dimensional part (14; 114; 414) built with an additive manufacturing system. a plurality of vessels (18; 118; 218; 418), each vessel comprising: a vessel body (40; 140; 440) having a top opening (44; 144; 444), the vessel body (40; 140; 440) being configured to retain an aqueous fluid (26; 126; 226; 426); and a porous floor (52; 152; 452) secured to and supported by the vessel body (40; 140; 440), wherein the porous floor (52; 152; 452) is configured to retain a three-dimensional part (14; 114; 414) and an attached support structure (15; 115; 415) built with an additive manufacturing system and inserted through the top opening (44; 144; 444); a plurality of impellers (60; 160; 460); and a vessel body (40; 140; 440) having a top opening (44; 144; 444), the vessel body (40; 140; 440) being configured to retain an aqueous fluid (26; 126; 226; 426); and a porous floor (52; 152; 452) secured to and supported by the vessel body (40; 140; 440), wherein the porous floor (52; 152; 452) is configured to retain a three-dimensional part (14; 114; 414) and an attached support structure (15; 115; 415) built with an additive manufacturing system and inserted through the top opening (44; 144; 444); a plurality of impellers (60; 160; 460); and a second component (16; 116; 216; 516) comprising: a surface (22; 122; 520) configured to operably receive the plurality of vessels (18; 118; 218; 418), such that one of the plurality of impellers (60; 160; 460) is rotatably mounted below the porous floor (52; 152; 452) of each of the plurality of vessels; and a plurality of rotation-inducing assemblies (48; 148; 248; 448), each rotation-inducing assembly located below the surface (22; 122; 520), and each one of the plurality of rotation-inducing assemblies (48; 148; 248; 448) being configured to rotate one of the plurality of impellers (60; 160; 460) with magnetic fields when one of the plurality of vessels (18; 118; 218; 418) is received on the surface (22; 122; 520) of the second component (16; 116; 216; 516) to agitate and direct flows of the aqueous fluid (26; 126; 226; 426) through the porous floor (52; 152; 452), thereby dissolving at least a portion of the attached support structure (15; 115; 415) to separate the support structure from the three-dimensional part (14; 114; 414) built with an additive manufacturing system. a surface (22; 122; 520) configured to operably receive the plurality of vessels (18; 118; 218; 418), such that one of the plurality of impellers (60; 160; 460) is rotatably mounted below the porous floor (52; 152; 452) of each of the plurality of vessels; and a plurality of rotation-inducing assemblies (48; 148; 248; 448), each rotation-inducing assembly located below the surface (22; 122; 520), and each one of the plurality of rotation-inducing assemblies (48; 148; 248; 448) being configured to rotate one of the plurality of impellers (60; 160; 460) with magnetic fields when one of the plurality of vessels (18; 118; 218; 418) is received on the surface (22; 122; 520) of the second component (16; 116; 216; 516) to agitate and direct flows of the aqueous fluid (26; 126; 226; 426) through the porous floor (52; 152; 452), thereby dissolving at least a portion of the attached support structure (15; 115; 415) to separate the support structure from the three-dimensional part (14; 114; 414) built with an additive manufacturing system.