LOW-TEMPERATURE CONVERSION OF SUGARCANE BY-PRODUCTS

This work reports the low temperature conversion (LTC) of the most imp ortant sugar-cane by-products, i.e., sugar-cane bagasse, filter mud, m olasses and alcohol sludge, into oil, char, reaction water and non-con densable gases. The oil was analysed for fatty acids and hydrocarbons. Active carbon was produced from the char and was characterized subseq uently. Filter mud gave the highest yield of LTC oil (20.6%), while ot her samples recorded yields lower than 6%. The heating values of the o ils were between 24.5 kJ g(-1) and 35.6 kJ g(-1). Thermogravimetric st udies of the LTC oil from filter mud indicated that 99% was vapourized at temperatures below 450 degrees C. Varying concentrations of C-8-C- 30 hydrocarbons were detected in the oil. The distribution pattern of hydrocarbons, however, was unusual compared to typical oils from LTC. The yields of LTC chars were between 35.4% and 77.6%. These chars have been activated and the conditions were optimized. Active carbon from bagasse recorded a high iodine and methylene blue number (1180 mg g(-1 ) and 275 mg g(-1) respectively). The BET surface is also very high (1 035 m(2) g(-1)) and consists of a large proportion of micro- and mesop ores. Active carbons produced from the other samples however exhibited also fairly high iodine, methylene blue and BET values. These results are discussed comparatively and the potential of the wastes is outlin ed. (C) 1998 Elsevier Science Ltd. All rights reserved.