Abstract: There are described methods, systems, and devices for automated digestion of samples contained in multi-sample racks. The method comprises receiving the multi-sample racks on at least one of a first level and a second level of a first rack loader, the first level and the second level superposed and held within a frame; managing rack positions on the first rack loader by displacing the multi-sample racks between the first level and the second level with at least one elevator; conveying the multi-sample racks into and out of a heating chamber of a microwave digestion system from at least one of the first and second levels; and controlling sample digestion inside the heating chamber through the application of microwaves by at least one microwave generator.