Technical Abstract: In this study, we used a commercial pilot-scale pyrolysis reactor system to produce combustible gas and biochar at 620 degrees Celsium from three sources (chicken litter, swine solids, mixture of swine solids with rye grass). Pyrolysis of swine solids produced gas with the greatest higher heating value (HHV) followed by the mixture of swine solids with rye grass and chicken litter. Relatively high sulfur-containing gases were produced; dimethyl sulfide and methyl mercaptan concentrations were higher than the Occupational Safety and Health Administration's permissible exposure limits. Biochar yield ranged from 43 to 49 percent based on dry weight with about 53 percent of carbon recovery. While the HHV of the chicken litter biochar was slightly below that of low rank coals, swine-based biochars had HHVs between high and low rank coals. Approximately 50 percent of the feedstock energy was retained in biochar and 25 percent in produced gases. Manure biochars contained higher concentrations of phosphorus and potassium than that of original manure feedstocks. Consequently these could be used as a low-grade fertilizer to improve soil fertility and crop yields. Extremely high energy (232.3 million joule/kilogram) was required to make 1 kilogram of biochar from wet swine manure with 97 percent moisture content (MC). However, dewatering of the wet swine manure to 75 percent MC substantially reduced the external energy requirement by 19 folds. Mixing of dried biomass such as rye grass with the dewatered swine solids almost eliminated the need for external energy.