Reactivity of char derived from Philippine coal under different environmental conditions

• Main Author: Dee, Maela Katherine P.
• Format: text
• Language: English
• Published: Animo Repository 1997
• Subjects: Coal; Reactivity (Chemistry); Pyrolysis; Coal gasification; Carbonization; Coal liquefaction; Chemical Engineering
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/1765
• Institution: De La Salle University

The primary objective of this study is to investigate the rate at which char react with the oxidizing gases during gasification. Char was derived from the pyrolysis of four kinds of Philippine coals, namely Bislig, Samar, Zamboanga, and Semirara. The behavior of Bislig, Samar and Semirara coal during pyrolysis is different from Zamboanga coal apparently due to the class to which these coals belong. The pyrolyzed char from each kind of coal was gasified utilizing air, carbon dioxide and oxygen as gaseous atmospheres. Rate of heating was varied in order to know its effect on reactivity. The effect of the following factors on gasification of Bislig, Samar and Zamboanga were also considered: mineral content, number of active carbon dioxide sites and kinetics of gasification.For each of the four coals analyzed, each has an environment and rate of heating which yield the highest reactivity. For Bislig, Samar and Semirara, oxygen gave the highest reactivity using 10 degrees centigrade per minute, 50 degrees centigrade per minute and 50 degrees centigrade per minute respectively. On the other hand, Zamboanga is most reactive in carbon dioxide at 50 degrees centigrade per minute. Of the four coals studied, Semirara is the most reactive followed by Bislig then Samar and finally by Zamboanga.The kinetics of Bislig, Samar and acid washed Zamboanga gasification was found out to be zero order while for Zamboanga, acid washed Bislig and acid washed Samar it was found to be second order. There was a remarkable increase in the reactivity of Bislig and Samar after minerals were removed due to the increase of available pores. On the contrary, Zamboanga decrease in reactivity due to loss of catalysts. Active carbon dioxide sites is directly proportional to reactivity for the three coals studied. This agrees with the assumption that gasification reaction is happening at the active carbon dioxide sites.