Processo de Transformação termoquímica dos cachos sem frutos de dendê (Elaeis guineensis, Jacq)

Abstract

The biomass thermal processing is an important operation to add value to the generated waste by palm oil industries. The objective of this work was to monitor the temperature influence (400, 500, 600 and 700°C) and the particle size in the thermal processing of palm fruit bunches without (PFB). It was used an apparatus for thermal processing containing a 4,4x10-4 m3 reactor, with possible recovery of solid and liquid products. The raw materials used were composed with PFB fractions of different particle size (entire sample (without screening), coarse fraction (retained on a 28 mesh sieve), mean fraction (retained on 60 mesh sieve) and fine fraction (retained in the sieve bottom)), which were properly characterized by immediate analysis, lignocellulosic composition, thermogravimetric and higher calorific power. In the solid products, it was made immediate analysis and higher calorific power value, on the other hand, in the liquid products, it was measured the higher calorific power, the density, the kinetic viscosity and the pH values. The solid maximum efficiency occurred at 400°C temperature, the gaseous product at 700°C temperature and the liquid had equivalent values at temperatures of 400, 500 and 600°C. The experiments raw materials showed lignocellulosic values between 45 to 53% of cellulose, 17 to 23% of hemicellulose and 30 to 40% of lignin in their composition. The thermogravimetric analysis showed higher degradation percentages at 300°C temperature, indicating a higher weight loss relative to the cellulose. The solid product showed higher percentages of fixed carbon and lower volatile percentages at 600 and 700 °C temperatures, also showed significant gains on the calorific power value, the results varied from 40.57 to 55.04% for the entire sample, from 56.74 to 70.12 % for coarse fraction, from 44.22 to 54.25% for mean fraction and 32.77 to 45.52% for fine fraction. The liquid product also showed significant gains in the calorific power value, the results varied from 56.48 to 68.59% for the entire sample, from 71.69 to 85.00% for coarse fraction, from 54.76 to 66.28% for mean fraction and 46.42 to 63.31% for fine fraction. Density values, kinematic viscosity and pH decreased with particle size reduction of PFB.