Energy balance and biodegradability assessments for food waste composting under various C:N ratios and air flow rates

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Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Gıda Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2015

Öğrenci: FUAT GÖKBEL

Danışman: DENİZ ÇEKMECELİOĞLU

Özet:

During composting process, there are various factors(C:N ratio, air flow rate, temprature, moisture, etc.) which affect the active phase of composting process and thus the biodegradability of organic wastes. The objective of this study was to examine the effect of different C:N ratios and air flow rates on in-vessel food waste composting. The temperature profile, moisture, organic matter loss, C:N ratio and biodegradability were measured. Energy balance was examined around the reactor, the heat loss and daily microbial heat generation were quantified. The maximum average temperature and the highest heat energy generation were obtained under the conditions of 20:1 C:N ratio and 3 L/min aeration rate, 46.7°C and 2.6 MJ respectively. The daily maximum biodegradation rate constant 0.088 d-1 and the highest energy generation per kg volatile solid (VS) 20.0 MJ/kg VS were reached under the conditions of 30:1 C:N ratio and 3 L/min aeration rate. All the experimental results and calculated variables showed that the optimum level of C:N ratio and airflow rate during food waste composting with forced aeration were 20:1 and 3 L/min, respectively.