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Solids/liquid separation of swine flushed manure and lagoon sludge with a centrifuge was evaluated with and without addition of lime, coagulant and flocculant. The separation system was developed by Environmental Renewal Technologies, LLC of Wilmington, NC and was evaluated in batch tests on a finishing hog farm with flush-tank system and anaerobic treatment lagoon. Separation efficiency of solids and nutrients were similar between the flushed manure and the lagoon sludge. Both sources had about 1 to 2 % total solids as pumped to the centrifuge. The centrifuge removed 40 to 50 % of suspended solids (SS), 60 % of total phosphorus (P), and 20 to 25 % of total nitrogen (N) without chemical additions. Adding a coagulant and flocculant increased removal to 75 % for SS, 70 % for P (flushed manure only) and 30 40 % for N. Adding lime as well as a coagulant and flocculant further increased the removal to about 85 % for SS and P, and about 45 % for N. The centrifuge cake had about 30 % dry matter and N and P concentrations usually in the range of 0.5 to 1.0 % on a wet basis. The cake resulting from tests with coagulant and flocculant was more spongy, and may be more difficult to further dry than solids without coagulant and flocculant.