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The objective of this study is to evaluate the efficiency of a skid-mounted pyrogasificaiton system for producing combustible gas from from animal manures: chicken litter; swine solids; and swine solids blended with rye grass. The skid-mounted pyrolysis system by the US Innovation Group, Inc. (USIG, Indianapolis, IN) is a pilot-scale, proprietary thermochemical conversion system that can produce combustible gases from various carbon wastes such as auto shredder residuals (ASM), sewage sludge, municipal solid wastes (MSW), etc. Eight to 19 L of dried swine solids, chicken litter, and blended swine solids (29% rye and 79% swine solids, w/w) were pyrolyzed in the reactor at 620oC (893K) for two hours. Swine solids produced gas with the highest higher heating value (HHV), slightly below that of natural gas, followed by the blend and chicken litter. Relatively high S-containing gases were produced; dimethyl sulfide and methyl mercaptan concentrations were higher than the OSHA PEL limits. While the HHV of the chicken litter biochar was slightly below that of low rank coals, both swine-based biochars had HHVs in between high and low rank coals. Approximately 50% of the feedstock energy was retained in biochar, 25% in produced gases, and 25% in oil/tar. Manure biochars contained higher concentrations of P and K compared to that of original manure feedstocks; consequently, these have potential use as a low-grade fertilizer to improve soil fertility and crop yields.