Chemical and spectroscopy characterization of a compost from food waste applying the hot composting Berkeley method

Purpose This study aims to characterize the compost produced under low input conditions in thirty days of composting from food wastes applying the hot composting Berkeley method (HCBM) by ۱۳C NMR CP/MAS techniques combined with evaluation of chemometric, physical and chemical parameters.Method The composting process from food waste was carried out following the recommendations of the Hot Composting Berkeley method. At ۷, ۹, ۱۱, ۱۳, ۱۵, ۱۷, ۱۹, ۲۱, ۲۳ and ۲۵ days turning was carried out, totaling eleven turns and the temperature, pH, electrical conductivity, dry density, potential CO۲ emission and potential NH۳ emission were quantified. The metal content in the compost was determined after ۲۵ days. The structural modifications of compost process were monitored by ۱۳C-NMR CP MAS spectroscopic and chemometrics analysis.Results Composting takes place immediately and continues for ۱۵ days through transformation to more labile lipid, carbohydrate and proteinaceous molecules (CAlkyl-H,R; CAlkyl-O; CAlkyl-O,N) with increasing temperature and pH. After ۱۵ days, there is a CO۲ and NH۳ emission reduction as well as preservation of recalcitrant molecules with more aromatic and nonpolar characteristics (CAromatic-H,R; CAromatic-O,N).Conclusion The compost obtained at ۲۵ days of composting by applying HCBM has greater hydrophobicity and aromaticity and is rich in mineral elements important for plant nutrition. The application of HCBM to food waste allowed to obtain a stabilized compost in ecological production conditions.

کلیدواژه ها:

Humification ، composting ، Spectroscopy ، Gas emission