Keywords: pirotubular boilers, burners, combustion, efficiency, injection pressure, nominal power, Spain, environmental pollution, pollutant emissions
Evaluation of the optimum efficiency of fire tubes boilers
Three-stage pirotubular boilers using gasoil C have been studied. Two boilers were connected in parallel. The data has been obtained by means of an analyser; its probe was connected at the exit of the boilers. The operation parameters considered were the injection pressure and the number of burners. As the emission of pollutants must be within the values prescribed by legislation, these are contemplated in the Spanish Royal Edict. It has been shown that the losses, owing to the sensible enthalpy of the fumes, increase as well as the carbon dioxide emission rate and the nominal power of the boiler, when increasing the injection pressure, while the concentrations of monoxide of carbon decrease. The maximum efficiency obtained for one burner with a pressure of 9 kg cm−2 was around 95.4%. For the case of two burners, the maximum value of efficiency obtained with a pressure of 12 kg cm−2 was about 93.2%.