Thermodynamic considerations about the way trom low to high pressure bagasse boilers

The bagasse boilers of actual sugar cane industry are passing from low (20 bar) to high pressures (110 bar). Nowadays, there is not a satisfactorily explanation regarding to this technological change. Certain authors refer the need of export electricity to the grid, considering the use of steam boilers and high pressure condensation extraction steam turbines. Others explain that the cause obeys mainly to economic reasons. This work presents the thermodynamic considerations about this technological change from low to high pressure bagasse boilers. The dependence between boiler efficiency and initial pressure is presented and discussed, also the statistical analysis is showed. The considerations used permits to observe the change step – by – step of efficiency as a function of initial pressure. Though the major trend of the boiler efficiency increase occur from 3500 to 6000 kPa, where the efficiency of the boiler rise up in 4,5 %, while these does not occur from 7000 to 9500 kPa, where the efficiency only rise up 3 %.