Name: RODOLFO DE MERLO VENTUROTT
Type: MSc dissertation
Publication date: 14/08/2017
Advisor:
Name |
Role |
|---|---|
| MARCIO FERREIRA MARTINS | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| MARCIO FERREIRA MARTINS | Advisor * |
| RAMON SILVA MARTINS | External Examiner * |
Summary: Nowadays there is a sanitation problem that affects billions of people around the world, especially in least developed countries. The lack of treatment of the faeces generates a proliferation of diseases, as diarrhea and cholera, causing malnutrition mainly in children that can lead even to death. The proper treatment of this waste is therefore essential to improve the quality of life of these affected people. Among the exiting solutions, one that is not very explored is gasification. Studies indicate the potential in the usage of faecal biomass to the production of combustible gases, since it has a high heating value if properly prepared, showing higher values than conventional biomass, like wood. In this context, the research presents a numerical approach in CFD for the simulation of a downdraft gasifier using faecal biomass. The methodology considers that the biomass particles that enter in the gasifier are analyzed in a lagrangean reference using the Discrete Phase Model, and the gas that occupy the domain is analyzed in an eulerian reference. The two phases interact with each other alternatively during the solution calculation until convergence is reached. The results seek to consider the influence of various parameters in the gasification process. The different sample compositions that were used indicated an impact of a higher amount of fixed carbon in the increase of the reactor temperature, which also impact in the quality of the produced gases. The increase in moisture content reduced the gases heating value, like in the increase of tar, and also reduced the reactor average temperature. The relative humidity has animpact in the hydrogen gas production due to the addition of water vapor in the gasifier. The study however presented relatively high efficiencies, which can be attributed to the pyrolysis specification, and there were also stability problems that were solved with solution relaxation.
Key words: Faecal biomass. Gasification. Downdraft gasifier. Computational Fluid Dynamics. Discrete Phase Model.
