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Animal manure represents a significant source of renewable bioenergy. In order to utilize current thermochemical energy conversion processes, a dry material (more than 90% total solids) is recommended. Solid-liquid separation can serve as a useful pretreatment of animal manure as a dewatering tool. Analyses were conducted to determine the effects of solid-liquid separation techniques and biological processing on the characteristics and energy content of swine manure. Specifically, four swine manure materials were examined: 1) homogenized house effluent, 2) separated solids from a belt, screen, and polymer injecting-rotary press solid-liquid separators, 3) anaerobic lagoon sludge, and 4) biologically processed solids from a composting facility. In addition to dewatering the aqueous waste stream, solid-liquid separation generated solids with similar volatile solids content yet different in fixed carbon, ash, and higher heating value (HHV). Rotary press separation with polymer flocculation produced a solid with the largest dry basis HHV, 9470 Btu/ lb, followed by belt separation (8782 Btu/lb), and screen separation (7191 Btu/lb). All of these solids had larger HHV than the homogenized flushed manure house effluent solids HHV (6441 Btu/lb). The increase in HHV is partially attributed to solid-liquid separation reducing the ash content of dried solids between 48 to 80%.