ESTUDO E TRATAMENTO CATALÍTICO DO ÓLEO DE PIRÓLISE DE LODO DE ESGOTO.

Abstract

In this work was applied the pyrolysis process, using the parameters of the Low Temperature Conversion (N2 atmosphere, temperature of 380 ° C and residence time 1.5 h), in the centrifuged sludge from a sewage treatment plant located in Rio de Janeiro, to obtain a new alternative fuels with high economic value added. Before the conversion, the sludge was dried and submitted to analysis of heating value, metals, sulfur and chlorine, and Soxhlet extraction. The fractions were analyzed by FTIR, NMR 1H and GC-MS. The thermo gravimetric technique (TGA) was also used and served to evaluate the thermal behavior of the sludge before thermo conversion. The pyrolysis oil yield from the sludge conversion was 7.1%, and preliminarily its heating value and the concentration of some metals were tested. The pyrolysis oil had a high heating value of 36 MJ/kg, which is about three times greater than that obtained for the dry sewage sludge. The chemical composition of the pyrolysis oil was analyzed by analysis of FTIR, NMR 1H and fractionation techniques by solvent extraction and chromatography. The fractions were analyzed by the techniques described above and by GC-MS. It was observed that the pyrolysis oil obtained from the low temperature conversion of the sludge is a complex mixture of hydrocarbons, oxygenates and nitrogen compounds. Mixtures of the pyrolysis oil obtained and commercial diesel were made in various proportions. These mixtures were submitted to quality control analysis for diesel fuel type. Preliminary results showed that the pyrolysis oil can be used as an additive to diesel in various proportions, creating a fuel that, after more detailed studies, could be used in stationary engines. The process of upgrade of pyrolysis oil to fuel fraction comparable to petroleum products was satisfactory. The upgrade used catalyst. The fractions obtained are predominantly aliphatic, and one of the fractions showed higher heating value equivalent to diesel of 40.028KJ/kg.