Revista industrial y agrícola de Tucumán
On-line version ISSN 1851-3018
FRANCK COLOMBRES, Federico J. et al. Monitoring of a bagasse drying system attached to a boiler in a sugar mill in Mexico. Rev. ind. agric. Tucumán [online]. 2010, vol.87, n.2, pp. 33-44. ISSN 1851-3018.
A bagasse dryer designed by Estación Experimental Agroindustrial Obispo Colombres was attached to a conventional bagasse boiler (Boiler No. 5) in a sugar mill in Mexico for evaluation. Measurement tests and material and energy balances for the boiler operating with and without the dryer were made. When supplied only with wet bagasse, boiler No. 5, with a nominal production of 60 t/h of steam and a maximum working pressure of 29 bar, could generate no more than 33 t/h of steam at 19 bar and 269 ºC, with an energy yield of 60.4% and an index of 1.6 kg steam/ kg of bagasse . When the dryer was attached, 28.6 tons of bagasse was dried from 50.2% moisture to 30.4%. Approximately 72% of that pre-dried bagasse, mixed with wet bagasse, was fed into the boiler, which then produced 58.4 t/h of steam, i.e. 77% more than without the dryer. The energy efficiency of the boiler-dryer system was 73.6% and the index was 2.0 kg steam/ kg of bagasse, i.e. 21.8%, 25% higher values than those for the original boiler. This increase in steam production allowed putting boiler No. 6 out of service. Boiler No. 6 produced about 20 t/h of steam with similar efficiency to that of boiler No. 5 without the dryer. These improvements resulted in energy savings of about 18%, as compared with the energy consumed by the two boilers (No. 5 and No. 6) when the dryer was not working. Energy saved amounted to 45.4 MJ/h, which is equivalent to 1103 l/h of fuel oil. This represents savings of USD 1.5 million per season.
Keywords : Measurements in boilers; Thermal energy; Energy efficiency; Biomass; Measuring equip.