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Animal wastes cause odor, breed disease, and environmental problems, effects that are becoming increasingly concentrated with larger-scale animal facilities. Our hydrothermal process reactor system (HPRS) creates an energy source from animal wastes by reforming their organic matter into oil with heat and pressure in an anoxic, aqueous environment. For various temperatures, pressures, retention times, and process gases, the three product streamsoil, gas, and process waterhave been analyzed for composition, purity, and safety according to ASTM, EPA, and other standard methods. From these product characteristics, the optimum operating parameters of the system have been determined.

The product oil was found to consist mostly of asphaltene and resin fractions with an initial boiling point around 300C. Heating values ranged from 2533 MJ/kg. Specific gravities were between 1.01 and 1.10 and sulfur content was between 0.240.6%. Optimum oil quality was achieved at 305C, 1500 psi, and 60 minutes retention time under nitrogen gas. Water analysis showed that the process eliminated coliform bacteria. BOD was reduced from manure on average by 86% and total suspended solids averaged 33 g/L, but both were still above EPA discharge guidelines. Inorganic ions and aqueous elements were generally found to decrease with increasing temperature. Organic compounds found in water include short chain organic carboxylic acids, alcohols and ketones, nitrogen-containing rings such as pyrazine, and aromatics such as phenol and ethylbenzene The gaseous stream was found to contain mostly nitrogen and carbon dioxide, however, small amounts of hydrocarbon gases and trace amounts of benzene and other EPA-regulated compounds were produced.