Production of pulp and energy using orange tree prunings

The aim of this work was to chemically characterize orange tree prunings and use it in pulping and combustion processes. Soda-anthraquinone pulping of the main fraction of orange pruning (stems with a diameter >0.5 cm) was simulated with polynomial and neurofuzzy models, that predicted pulp properties as a function of operating variables (155–185 °C, 40–90 min, soda concentration, 10–16%) with errors less than 20%. The heating values (16,870 kJ/kg), the flame temperature (1150–2150 °C) and dew point temperature of fuel gas (47–53 °C) for the residual fraction from orange pruning (stems diameter <0.5 cm and leaves) was determined and compared with other non-wood lignocellulosic materials. As a consequence the price of kJ obtained by combustion of this residual fraction is less than other lignocellulosic materials, much lower than those of fossil fuels.