Acoustophoretic devices are disclosed. The devices include a flow chamber, an ultrasonic transducer, a reflector, an inlet, a filtrate outlet, a concentrate outlet, and optionally a lipid collection trap. The ultrasonic transducer and reflector create a multi-dimensional acoustic standing wave in the flow chamber that traps and separates red blood cells and/or lipids from blood. Concentrated red blood cells can be recovered via the concentrate outlet, the lipids can be recovered via the lipid collection trap, and the remaining blood can be recovered via the filtrate outlet. Methods for separating blood components (e.g., red blood cells, lipids, platelets, white blood cells) from blood are also disclosed. The red blood cells can undergo washing with a solvent to remove undesired admixtures. Cryoprotectants can be added or removed from the blood.