University of Zagreb, Faculty of
Chemical Engineering and Technology, Division of Industrial Ecology, *Division
of Reaction Engineering and Catalysis 10000 Zagreb, Croatia, Phone: +385 1 4597
269 Fax: +385 1 4597260 E-mail: fbriski@fkit.hr
Abstract
Solid waste generated by tobacco industry contains mostly tobacco particles and flavoring agents. Its main characteristics are high contents of nicotine, which is toxic, and total organic carbon in the aqueous extract. Therefore, tobacco waste must be separated from urban waste. The aim of this work was to stabilize tobacco solid waste by aerobic composting. The experiments were carried out in the closed thermally insulated column reactors (1 L and 25 L) under adiabatic conditions over 16 days. Monitoring covered temperature changes in the reactor, CO2 production and the numbers of mesophilic and thermophilic population in the mixed microbial culture. During the process the highest temperature was 64 °C, pH varied between 7.85-9.25 and moisture content in composting mass was between 65.8‑76.5%. By the end of the experiment total solids in tobacco waste were reduced by approximately 50% and nicotine by 90%. Biodegradation rate of organic fraction in solid waste was simulated using the empirical model. It was found out that the selected model describes aerobic composting fairly well and confirms the hypothesis that the released heat is proportional to the biodegradation process.