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The growth of North Carolina's swine industry in recent decades has led to a subsequent increase in the production of swine manure. This manure represents a potential threat to environmental and human health, as well as an opportunity to add value to pork production. Technologies for treating swine manure safely while generating products to offset costs are part of an expanding field of research centered on sustainable food production for our growing population. Thermochemical conversion processes use heat to degrade organic feedstocks and drive chemical reactions, which generate valuable products. The high moisture content of swine manure is prohibitive for most thermochemical processes, but gasification and hydrothermal carbonization may be more accommodating. Gasification, a time-tested thermochemical conversion process, yields a combustible gas through a series of endothermic reactions, and hydrothermal carbonization yields a solid, coal-like char that can be used as a fuel or chemical precursor. Advances in thermochemical conversion processes have indicated the potential for yielding valuable products from swine manure, but viable scalable processes are still under development, requiring further research to apply these processes to swine manure management and evaluate the usefulness of their products. This review (1) describes, generally, thermochemical conversion via both hydrothermal gasification (HTG) and hydrothermal carbonization (HTC), (2) shows the usefulness of each conversion process for biomass, and (3) discusses the potential of HTG and HTC of swine manure to enhance the value of pork production. [ABSTRACT FROM AUTHOR]

In this study, concentrations of bacteria and fungi were measured in two high-rise, tunnel-ventilated egg production houses in North Carolina during winter, spring, and summer using Andersen six-stage samplers. Average concentrations of culturable airborne bacteria and fungi ranged from 2.2 x 105 colony forming units (CFU) m-3 to 1.1 x 106 CFU m-3 and from 1.5 x10³ to 2.8 x 10³ CFU m-3, respectively. In-house bacterial concentrations significantly differed over the three seasons but did not vary by time of day. In-house fungal concentrations were not significantly different over seasons or at different times of day. Among all influencing factors, indoor air temperature (T), relative humidity (RH), and house ventilation rate (Q) had significant impacts on in-house bioaerosol concentrations. Bacterial concentrations were significantly higher on the second floor of the high-rise layer house, while fungal concentrations were not significantly different on the two floors. Emission rates of both bacteria and fungi were highest in summer, possibly due to the elevated ventilation rates during the summer season. The findings of this study advance our knowledge about bioaerosol concentrations and emissions as impacted by various factors in egg production facilities. [ABSTRACT FROM AUTHOR]