Estudo comparativo sobre a ação de composto, biocarvão e celulase no processo de compostagem de tabaco em reator facultativo

Abstract

One of the most viable alternatives for the treatment of various organic wastes, including tobacco from seized cigarettes, is composting in a facultative reactor. There are many studies on the use of additives to optimize composting, improving the quality of the final product and/or reducing the process time. However, no studies have been found comparing the action of different additives acting individually on the same substrate. In this work, a comparative study was carried out on the influence of three additives (compost, biochar and cellulase) on the composting of tobacco from seized cigarettes, with organic food waste and sawdust, in a facultative reactor. Four reactors were built. In one of the reactors, only the substrate was added, while in the others the additives were added separately, one in each reactor, according to the proportions recommended in the literature. The process was monitored and the evaluation of the compost obtained was carried out by means of physical-chemical and spectroscopic parameters and phytotoxicity analysis. The reactor temperatures reached peaks of up to 60 °C, remaining around 50 °C during the thermophilic phase in the three reactors with additives, which was sufficient to achieve compost stability. At 110 days, the seed germination index (SGI) exceeded 95% in the three reactors with additives. In all reactors, the reduction in the E2/E3 and E4/E6 (UV/Vis) ratios and the data obtained by FTIR and 13C NMR indicated that degradation of the simplest molecules occurred, and there was an increase in the humification indexes and condensed aromatic clusters. The data obtained demonstrated the efficiency of the additives in composting for the treatment of tobacco in a facultative reactor, as they presented better results than those of the reference reactor. Biochar was the additive that demonstrated the greatest efficiency, followed by cellulase in second place, and compost in third place.