Refining of Soda-AQ, Kraft-AQ, and Ethanol Pulps from Orange Tree Wood

Abstract

The pulp yield of orange tree wood was tested under various conditions including processing with soda-anthraquinone (soda-AQ), kraft-anthraquinone (kraft-AQ), or ethanol under different temperature, time, reagent concentration, and PFI laboratory beater beating regimes. Beating grade and stretch properties were studied, with a view to identifying the optimum operating conditions. Polynomial equations were derived that generally reproduced the dependent variables, with errors in most cases much less than 20%. Kraft-AQ pulping was the most efficient. The values of the tensile, burst, and tear indices obtained with kraft-AQ (78.04 Nm/g, 4.84 kN/g, and 2.97 mNm2/g, respectively), were in most cases higher than those found for soda-AQ and ethanol pulps. Using lower values of operational conditions than those required to maximize the studied paper properties (170 °C, 65 min, 13% active alkali, and 2700 number of PFI beating revolutions), it was possible to provide a more energy- and chemically-efficient process for industrial facilities.