Location: Bioenergy ResearchTitle: Combined borax and tannin treatment of stored dairy manure to reduce bacterial populations and hydrogen sulfide emissions Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/24/2011
Publication Date: 5/24/2011
Citation: Spence, C., Seymour, K., Whitehead, T.R., Cotta, M.A., Hengemuehle, S., Yokoyama, M. 2011. Combined borax and tannin treatment of stored dairy manure to reduce bacterial populations and hydrogen sulfide emissions [abstract]. American Society for Microbiology. Paper No. 2809. Interpretive Summary:
Technical Abstract: Background: Anaerobic digestion of organic residues in stored livestock manure is associated with the production of odors and emissions. Hydrogen sulfide (H2S) is one such emission that can reach hazardous levels during manure storage and handling, posing a risk to both farmers and livestock. New technologies must be identified to reduce the hazard of H2S emissions that are cost effective, safe to use, and environmentally sustainable. Previous treatments with borax or quebracho tannins have been shown to reduce H2S emissions in stored swine manure. This study investigates the combined treatments of these inhibitory compounds on stored dairy manure to reduce H2S emissions. Methods: Dairy manure was recovered from storage pits and incubated anaerobically at room temperature for 11 days in Erlenmeyer flasks with combination treatments of borax and quebracho tannins ranging in concentrations from 0–0.3% w/v. Headspace gas was monitored daily for H2S emissions and aliquots of manure were analyzed by quantitative real time polymerase chain reaction for enumeration of bacterial populations at the end of the incubation period. Results: Borax and tannin combinations were effective in decreasing H2S emissions. A combination of 0.1% tannins + 0.2% borax reduced H2S emissions by 99% over the course of the experiment. At lower concentrations, borax was shown to be more effective than tannins. Borax (0.1%) alone was shown to reduce H2S emissions by 95%, whereas 0.1% tannins alone reduced H2S emissions by only 30%. The total bacterial population in the manure was reduced by combination treatments of borax and tannins with the 0.2% borax + 0.3% tannins combination being most effective in reducing the population by 94% at the end of the incubation period. Conclusions: Combined treatments of borax and tannins effectively reduced H2S emissions and total bacterial populations in stored dairy manure. Further studies are needed to determine the effects of these treatments on the sulfate reducing bacterial population in stored dairy manure.