(615f) Investigation of Effective Parameters on Biomass Gasification in Circulating Fluidized Bed Gasifiers

Gasification of biomass is one of the technologies to convert solid fuel to gas for heat and power production. Gasification mechanism and efficiency has been studied for decades. However due to the complexity of the system and its sensitivity to operating parameters, the relations and impacts of different parameters on the gas quality and gasifiers performance are still not clear.

In this paper data that are collected from different Circulating fluidized bed gasifiers have been analyzed to detect the most influential operating parameters. The gas composition, carbon conversion and heating value of the gas are considered as the evaluation indexes to measure the quality of the product gas and gasifiers performance.

The multivariate analysis statistical tool has been used in this study. Principal component analysis (PCA) shows the grouping between different gasifiers and the positive/negative correlation between operating parameters and concentration of different components in the product gas. Also the influencing parameters on carbon conversion and heating value of the gas have been investigated.

The results show a strong negative correlation between CH₄ and CO with equivalence ratio (ER). This means that increasing ER value would decrease CH₄ and CO concentration. This happens since the reactions move more towards combustion. On the other hand H₂ shows a strong positive correlation with temperature, pressure and steam to biomass ratio (S/B). This can be related to cracking of larger hydrocarbons in higher temperature and larger S/B. However due to the exothermic characteristic of water gas shift reaction, higher temperature would result in lower CO₂ amount which proves the negative correlation between H₂ and CO₂ in this analysis.