abstract
In recent years there has been a constant growth in using biomass as an energy source. The most common use is for thermal conversion by direct combustion. However, the viability of this equipment depends on the quality of the thermochemical conversion of the fuel, optimizing the combustion process is key to maximize its performance. Among the parameters of the process, the oxidizing agent plays a fundamental role, due to the influence it presents over other variables in the process. The experimental work focused on analyzing and optimizing the supply and air distribution in a 580 kWth industrial biomass boiler, developed by the Portuguese manufacturer Ventil - Engenharia do Ambiente, during the burning of pinewood pellets. It was possible to conclude that the boiler operates under a high value of excess air, as a consequence of incorrect distribution of the air in the furnace and the PID control system, which is reflected on the energy performance of the system. Furthermore, the system proved to have good stability under continuous operation, guaranteeing a regular supply of energy. The pollutant emissions, in particular CO and NO, was low, which indicates that the installation has a high environmental quality performance. The cost of thermal energy production in the system is 0,05 €·kWhth-1, which is a competitive price when compared to other fuels. For the combustion technology in the case study, a number of opportunities were identified to optimize the system which require further analysis.
authors
Luís Ruivo
our authors
Luís Carlos Marques Ruivo
PhD Studentsupervisors
Luís Tarelho