Dose-dependent effects of sodium dodecyl sulfate and hydrogen peroxide treatments on methane emission from pig manure during storage.

Mitigation of methane (CH) emissions from slurry pits within pig barns can be achieved through treatment of residual slurry left after frequent flushing of the slurry pits. In this study, dosages of additives such as sodium dodecyl sulfate (SDS) and hydrogen peroxide (HO) were optimized to achieve reduction in CH emissions from residual pig slurry during storage. In addition, the effects on emissions when both the treatments were combined and the effects of SDS treatment on slurry acidified with sulfuric acid (HSO) were studied in order to reduce CH and ammonia (NH) emissions from residual pig slurry storage. A maximum of 98% and 70% reduction in CH emissions were achieved with SDS and HO treatments, respectively. The combination of SDS and HO did not increase efficiency in reducing CH emissions compared to SDS treatment alone. Whereas the application of SDS to slurry acidified with HSO (pH 6.2) increased the CH mitigation efficiency by 15-30% compared to treating slurry with only SDS. The combined treatment (SDS + HSO) reduced NH emissions by 20% compared to treating slurry with HSO (pH 6.2) alone. Hereby, combined treatment (SDS + HSO) can reduce both CH and NH emissions, with a reduced amount of chemicals required for the treatment. Hence, application of SDS at concentrations <2 g kg to acidified slurry is recommended to treat residual pig manure in pig barns.