Eventos Anais de eventos
ENCIT 2016
16th Brazilian Congress of Thermal Sciences and Engineering
NUMERICAL SIMULATION OF OXY-FUEL AND CO-FIRING PROCESS OF COAL AND BIOMASS IN A REAL SCALE BOILER
Submission Author:
Cristiano Vitorino da Silva , RS , Brazil
Co-Authors:
Fernando Pereira, Maria Luiza Sperb Indrusiak, Paulo Smith Schneider, Pedro Bellani
Presenter: Cristiano Vitorino da Silva
doi://10.26678/ABCM.ENCIT2016.CIT2016-0679
Abstract
This paper performs a numerical study in CFD about the oxy-fuel process of a mixture of coal with woody biomass in an actual steam generator of approximately 320 MW in a co-firing process. The aim of this study is to verify the feasibility of this steam generator to work with this combustion process which is going to be a global trend, since its application can reduce the environmental impact due to emissions, going to meet the increasingly demanding legal issues. A numerical model, based on the technique of finite volumes was implemented in ANSYS CFX software for the solution of differential equations of conservation of mass, momentum, energy and chemical species and turbulence and radiation models. Different study cases involving co-firing and oxy-fuel process were analyzed to compare with the actual operation conditions of the equipment, which burns pulverized coal, verifying the possibility of implementing this new alternative to burning also biomass. Results showed that oxy-fuel combustion processes, and co-firing, when evaluated in separate processes, presented pollutant reductions, such as NOx, CO and CH4. However, the addition of biomass also reduces the flame temperature, in comparison with the actual burning process using just coal as a fuel. Combining the two methods, a significant reduction in pollutants was achieved, keeping almost the same levels of temperature inside the furnace, however with a significant decrease in the average heat flux on the walls.
Keywords
Pulverized Coal, Biomass, CFD, Co-firing, Oxy-fuel
