PEREIRA, R. A.; http://lattes.cnpq.br/7652983337076633; PEREIRA, Rafaela Alves.
Résumé:
Composting processes have established themselves as efficient procedures for minimizing
environmental issues and reducing the volume of discarded organic solid wastes. This work
aims at studying small scale composting processes as a useful alternative for tackling
agroindustrial residues issues in a semiarid region of Paraíba State, Brazil. For this, two
compost piles were set (one placed on compacted soil and the other one on a concrete patio)
and monitored by observing parameters such as temperature, moisture, pH, reduction in dry
matter and volatile solids for 73 days. The maturity was assessed by the C/N ratio, electrical
conductivity, and chemical oxygen demand. The characterization of the final compound was
carried out by using total nitrogen, pH, moisture and C/N ratio. The produced compounds
were also used to check the germination of tomato considering various proportions (0%, 10%,
20% and 40%) of compound mixed with a regional soil. As the composting process
conducted on the patio, the treatment on soil also achieved temperatures between55 and60°C
during the process. As for the volatile solids, the compounds produced directly on soil out
performed those obtained on concrete patio, with reduction of its initial value of about
69.94%.The results suggest that the studied organic compounds were maturated at 73 days of
cure, indicating that the application of simple methods is considered to be safe for verifying
composting processes. The compounds based on agroindustrial wastes reached almost all the
requirements requested by Brazilian law. Regarding to the performance of tomato
germination, the substrates obtained from the soil-based compounds outperformed those using
the compounds produced in concrete patio. The small scale composting processes were shown
to be effective for treating agroindustrial wastes in semiarid Paraíba, Brazil, and the derived
substrates have proved to be suitable for germination of tomato.
