Resumo

ISAZA-ARIAS, GC; PEREZ-MENDEZ, MA; LAINES-CANEPA, JR  e  CASTANON-NAJERA, G. Comparison of two ventilation techniques in the decomposition of organic matter. Universidad y ciencia [online]. 2009, vol.25, n.3, pp.233-243. ISSN 0186-2979.

Aerobic composting is the most frequently used biological process for the conversion of organic waste into a stable humic material known as compost, that is used as a product to improve soil. In this study, two ventilation techniques for the decomposition of organic matter composed of gardening waste and citric fruit peels were compared. One was a static pile with forced ventilation (two daily ventilations) and the other pile followed the traditional method of periodic manual turning over (two weekly turnings). Each pile contained 1500 kg of gardening waste and 220 kg of chopped citrus peel. The garden waste was obtained from the campus of the División Académica de Ciencias Biológicas, and the citrus peels were gathered from a fruit store in Villahermosa, Tabasco. The decomposition process lasted 120 d. The analytical determinations of Temperature, Humidity, pH, Electrical Conductivity, Organic Matter, Organic Carbon, Total Nitrogen and Phosphorus were carried out according to the NOM-021-RECNAT-2000. Results showed that the temperature at the end of the process was similar in both treatments (36 °C). The final values of Humidity, Electrical conductivity, pH, Organic matter, Organic Carbon, Nitrogen, C/N ratio and Phosphorus in the treatment with forced ventilation were 57.22%, 1.73 dSm^-1, 7.95, 39.27%, 21.82%, 1.21%, 18.70 and 277 mg kg^-1 respectively, and those for the treatment with manual turning were 64.74%, 1.0 dS m^-1, 8.23, 42.80%, 23.78%, 1.46%, 16.51 and 217 mg kg^-1 respectively.

Palavras-chave : Garden waste; citrus peels; compost; ventilation types.