Rodrigo Monteiro and Danilo L. Halla
Fuzzy logic, Advanced process control, Energy efficiency, Steam generation
Sugar cane bagasse is used as fuel in high pressure boilers to generate superheated steam in sugar and alcohol plants. Steam is used for heating others process of the plant as distillation columns, evaporators, etc. Also it is used to generate electric energy on turbines. The main parameter of steam generation is steam pressure. Since many variables, as the consumption of steam and physical and chemical properties of the bagasse interfere on the combustion process, the pressure control is not effective, leading to a large variability on the process. The current work presents and advanced process control application, based on fuzzy logic, on high pressure boilers and electric generator turbines, in order to control steam pressure and electric generation. The software is not based on phenomenological knowledge. It uses empirical rules to estimate control parameters. By anticipating consumption disturbances and allying the boilers and generators controls to work together, variability of steam pressure was reduced by 34.5%, leading to an improvement of 1.2% and 0.4% on steam and electric energy generation efficiency, respectively.