Title : Cleaner syngas from biomass gasification: Is K-Feldspar the key?
Abstract:
The selection of bed materials in fluidized bed gasification (FBG) is a key factor in optimizing syngas quality and minimizing contamination. This work presents a pilot-scale comparison of olivine and K-feldspar as bed materials during the gasification of almond shells, a widely available arboreal biomass. Gasification experiments were performed using a 1 kWth bubbling fluidized bed reactor at CREA’s LASER-B laboratory under controlled conditions.
Syngas was analyzed in terms of composition (H?, CO, CH?, CO?, O?) and contaminants, including tars, VOCs, and heavy metals. Results show that K-feldspar produced a more hydrogen-rich syngas (46% H?) compared to olivine (39% H?), and significantly lower emissions of heavy metals, especially Ni, Cu, Zn, Cd, Sn, Ba, and Pb. Only chromium (Cr) showed higher levels with K-feldspar, in agreement with previous lab-scale results.
In terms of tar and VOC content, both materials exhibited similar performance except for Benzo[b]fluoranthene, which was notably higher with K-feldspar. Overall, K-feldspar proved more effective in minimizing syngas contamination and maximizing hydrogen yield, highlighting its suitability for clean energy generation in internal combustion engines or fuel cells.
Audience Take Away Notes:
- How bed material composition influences syngas quality and contamination levels.
- The operational benefits of using K-feldspar over olivine in biomass gasification.
- Methods for monitoring and analyzing heavy metal, tar, and VOC emissions.
- Strategies to improve the environmental performance of small-scale FBG systems.
- How lab-scale findings can be validated and scaled to prototype applications.
