Sulfur-fixation effect by coal-biomass briquettes under simulated combustion conditions of household stoves

• Published in: Journal of Japan Society for Atmospheric Environment / Taiki Kankyo Gakkaishi Vol. 43; no. 5; pp. 264 - 272
• Main Authors: Yamada, Kimiko, Wang, Qingyue, Sakamoto, Kazuhiko
• Format: Journal Article
• Language: English
• Published: Japan Society for Atmospheric Environment 01.09.2008
• Subjects: ash content; coal-biomass briquette; combustion temperature; heating value; sulfur-fixation ratio; thermal decomposition
• ISSN: 1341-4178; 2185-4335
• DOI: 10.11298/taiki1995.43.264

Combustion experiments of four types of coal-biomass briquettes in laboratory were conducted to examine sulfur-fixation ratios under simulated combustion conditions of Chinese household stoves. We evaluated the factor such as combustion temperature that affected sulfur fixation ratios. Sulfur-fixafion ratios for coal-biomass briquettes (Ca/S=2) ranged from 88% to 96% under 800°C that was assumed in previous laboratory experiments. On the contrary, those ranged from 33% to 71% under 1000°C that was observed in Chinese household stoves, which decreased from 26% to 63% for each coal-biomass briquette in comparison with those under 800°C. The decrease of sulfur-fixation ratios resulted from sulfur-emission during combustion of coal-biomass briquette char and transformation of calcium compounds in combustion ashes of coal-biomass briquettes, owing to thermal decomposition of fixed sulfur (CaSO4) in char combustion over 850°C. Additionally, sulfur-fixation ratios under 1000°C depended on types of coals, which were different in heating value, ash contents, and metal components. The laboratory combustion results indicated the necessity and importance of selection of coal types as raw material for coal-biomass briquettes according to application in terms of reduction of sulfur-emission.