Effect of mixing ratios of natural inorganic additives in removing ammonia and sulfide in the liquid phase during anaerobic digestion of slaughterhouse waste

Mutegoa, E.; Malima, N.M.; Hilonga, Askwar; Njau, K.N.

dc.creator	Mutegoa, E.
dc.creator	Malima, N.M.
dc.creator	Hilonga, Askwar
dc.creator	Njau, K.N.
dc.date	2022-03-08T10:11:13Z
dc.date	2022-03-08T10:11:13Z
dc.date	2021
dc.date.accessioned	2022-10-20T13:09:30Z
dc.date.available	2022-10-20T13:09:30Z
dc.identifier	Mutegoa, E., Malima, N. M., Hilonga, A., & Njau, K. N. (2021). Effect of mixing ratios of natural inorganic additives in removing ammonia and sulfide in the liquid phase during anaerobic digestion of slaughterhouse waste. Materials Today Chemistry, 20.
dc.identifier	DOI:10.1016/j.mtchem.2020.100415
dc.identifier	http://hdl.handle.net/20.500.12661/3442
dc.identifier.uri	http://hdl.handle.net/20.500.12661/3442
dc.description	Abstract. Full text available at https://doi.org/10.1016/j.mtchem.2020.100415
dc.description	In this study, the efficacy of inorganic additives in the removal of total ammonia nitrogen (TAN) and sulfide in the aqueous phase of slaughterhouse waste undergoing anaerobic digestion in the batch reactor was investigated. A mixture of natural inorganic additives processed from the anthill and red rock soil samples collected from Arusha, Tanzania were used as adsorbents in different ratios. These materials were chosen in regard to their abundance in the local environment, surface properties, and elemental composition. Before analysis, the materials were pulverized and calcined at 700 and 900 °C for 2 h in a furnace and then sieved to 250 μm fine particle size. XRD analysis revealed that the anthill soil sample is endowed with major mineral phases of quartz and hematite while red rock soil contains albite, pyroxene, and quartz as predominant phases. The anthill and red rock soil samples calcined at 900 °C displayed higher BET surface areas of 815.35 and 852.35 m2/g, respectively. The mixture of anthill soil and red rock soil in a ratio of 3:1 had a higher TAN removal efficiency of 92% at a contact time of 30 min compared to other ratios. On the other hand, a ratio of 1:2 showed a higher sulfide removal efficiency of 79% at a contact time of 60 min. Adsorption isotherm studies revealed that the Jovanovich model fitted better to the experimental data than the Langmuir and Freundlich models. The results demonstrated further that inorganic additives have a synergistic effect on stimulating methanogenesis as well as eliminating ammonia and sulfide during anaerobic digestion of slaughterhouse waste. Our findings demonstrate that anthill and red rock soils can be exploited as affordable, ecofriendly, and efficient adsorbents for mitigation of TAN and sulfide from the liquid phase and sustenance of methanogenesis.
dc.language	en
dc.publisher	Elsevier
dc.subject	Methanogenesis
dc.subject	Adsorption
dc.subject	Calcination
dc.subject	Sulfide
dc.subject	Total Ammonia Nitrogen
dc.subject	TAN
dc.subject	Tanzania
dc.subject	Anaerobic digestion
dc.subject	Inorganic additives
dc.title	Effect of mixing ratios of natural inorganic additives in removing ammonia and sulfide in the liquid phase during anaerobic digestion of slaughterhouse waste
dc.type	Article