Energy and emission properties of burley tobacco stalk briquettes and its combinations with other biomass as promising replacement for coal.

As a tobacco producer, Serbia has to deal with large amounts of leftover tobacco stalks after harvesting. One option for this type of biomass is to burn it, but burning is not encouraged in Serbia, since the levels of its combustion products have not been investigated yet. The aim of this study was therefore to determine the elemental composition, ash and nicotine content, heat values, and composition of gaseous combustion products of tobacco stalk briquettes and to see if their mixing with other types of biomass available in Serbia could improve their ecological profile. We made 11 different types of briquettes: six of pure raw materials, including burley tobacco stalks, sunflower head remains, wheat straw, corncob, soy straw, and beech sawdust and five by mixing tobacco stalks with these other raw materials in a 50:50 mass ratio. All briquettes meet the ecological criteria regarding the emission limits for nitrogen oxides (NOx), sulphur dioxide, carbon monoxide, and carbon dioxide. Nicotine content in flue gases (<10 mg/kg) is far below the maximum level allowed by the European Union. Heat values of all biomass samples are acceptable, although lower than those specified for solid biofuels (≥16.0 MJ/kg), save for corncob and beech sawdust and their mixtures with tobacco stalks. Our findings therefore encourage the use of tobacco stalks as a viable biofuel.

The influence of tobacco blend composition on carbon monoxide formation in mainstream cigarette smoke.

The aim of this study was to examine the impact of three main tobacco types (flue-cured FC, air-cured AC and sun-cured SC) and two tobacco-based materials (reconstituted tobacco - recon RT and expanded stem) on the formation of carbon monoxide (CO) in the gas phase of mainstream cigarette smoke. The results showed that the type of tobacco examined had a significant impact on the amount of carbon monoxide production in the gas phase of cigarette smoke. AC and SC tobaccos had the most evident impact. The amount of tobacco in mixtures M1, M2 and M3 as well as the addition of expanded stems had an impact on the amount of CO formed in the cigarette smoke. There is weak correlation between CO content in the smoke and the chemical composition of the tobacco. Draw resistance had an impact on CO production. The research results are of great importance, since tobacco selection is the first step in the production of cigarettes with reduced emission of harmful elements contained in the smoke.