Untapped potential of zeolites in optimization of food waste composting. (1st July 2019)

• Record Type: Journal Article
• Authors: Waqas, M.; Nizami, A.S.; Aburiazaiza, A.S.; Barakat, M.A.; Asam, Z.Z.; Khattak, B.; Rashid, M.I.
• Is Part Of: Journal of environmental management. Volume 241(2019)
• Page Start: 99
• Page End: 112
• Publication Date: 2019-07-01
• Subjects: Food waste -- Natural zeolite -- Modified natural zeolite -- Organic matters -- Compost; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2019.04.014
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: This study aims to examine the effect of zeolites in optimizing the process of food waste composting. A novel method of sequential hydrothermal was introduced to modify the natural zeolite and apply to in-vessel compost bioreactors. Raw and modified natural zeolites were applied at 10 and 15% (w/w) of the total waste and compared with un-amended control trial. Both raw and modified zeolites affected the composting process, but the notable results were observed for modified natural zeolite. The results for compost stability parameters were prominent at 15% modified natural zeolite concentration. The rapid and long-term thermophillic temperature and moisture content reduction to the optimum range was observed for modified natural zeolite. Furthermore, the total ammonium (NH4 + ) and nitrate (NO3 − ) concentration in modified natural zeolite were increased by 11.1 and 21.5% respectively as compared to raw zeolite. Compost stability against moisture contents (MC), electrical conductivity (EC), organic matters (OM), total carbon (TC), mineral nitrogen, nitrification index (NI) and germination index (GI) was achieved after 60 days of composting that was in accordance with the international compost quality standards. The findings of this study suggested the suitability of modified natural zeolite addition at 15% to the total waste as the optimum ratio for the composting of food waste in order to achieve a stable nutrient-rich compost. Graphical abstract: Image 10988 Highlights: Natural zeolite was modified using a novel sequential hydrothermal treatment method. Raw and modified natural zeolite were applied at 10 and 15% (w/w) of the total waste. 15% concentration of modified natural zeolite showed significant compost stability. The rapid thermophillic temperature was achieved for modified natural zeolite. Total NH4 + and NO3 − concentration were increased by 11.1 and 21.5% in modified natural zeolite.