Desulfurization of coal by pyrolysis and hydropyrolysis with addition ofKOH/NaOH

摘要

In this paper, a two-step desulfurization process from high sulfur coals was investigated. TwornChinese coals with addition of 10wt% potassium hydroxide or sodium hydroxide were pyrolyzedrnunder atmosphere of nitrogen or hydrogen in a fixed bed reactor at 600℃, and then the obtained charsrnwere washed by hot water. The experimental results indicated that without addition of alkalirncomponent, sulfur removal of these two coals by pyrolysis and hydropyrolysis is about 40～50% andrnsulfur content of chars reduces a little in comparison with the original coals; with addition of 10wt%rnpotassium hydroxide or sodium hydroxide into the original coals and chars being washed by hot water,rnthe sulfur removal is about 70～80%, and sulfur content in chars is dramatically reduced. Therncombustion behavior of chars was also investigated by a thermogravimetric analyser. The resultsrnshowed that those chars with alkali component added as well as water-washing are more reactive andrncan be burned more easily than those without alkali added.