Study of inexpensive oxygen carriers for chemical looping combustion

Feasible utility of inorganic remains from potable water purification process in chemical looping combustion studied in TG

“…Due to the high oxygen content available for the CLC reaction, the preferred temperature for combustion with Fe-based sediments should be at least 800°C, to maximize both the oxygen capacity utilized for the redox reaction and reaction rates. Because in thermal systems, the Fe 2 O 3 /Fe 3 O 4 reaction is expected to be applied, there is still a remarkable oxygen capacity for naturally occurring carriers [17,22].…”

“…Nevertheless, there is little research on naturally occurring chemical looping materials. Recently, some minerals [13][14][15][16][17][18], industry wastes [18][19][20][21][22][23], and concentrates from minerals [20] have been considered as inexpensive oxygen carriers for CLC. Mostly natural minerals such as ilmenite (FeTiO 3 ) have been examined in the past [13][14][15][16].…”

“…The initial oxygen transport capacity was measured to be approximately 4 %, then decreased as the number of cycles increased, dropping to 2.1 % after 100 redox cycles. Moreover, [22] observed that complete reduction activation was relatively fast with gasification products. Complete activation took place after 6 redox cycles.…”

“…He also concluded that the Fe 2 O 3 -based ores possessed greater oxygen utilization but required an activation period before achieving full performance in methane CLC. Other studies have indicated the potential of manganese ore [22]. Fossdal et al [22] tested a manganese ore, selected as a promising carrier for CLC purposes, that showed a maximum oxygen capacity of 4.9 % at 1,000°C.…”

“…Other studies have indicated the potential of manganese ore [22]. Fossdal et al [22] tested a manganese ore, selected as a promising carrier for CLC purposes, that showed a maximum oxygen capacity of 4.9 % at 1,000°C. The addition of an excess of calcium to manganese resulted in the formation of calcium manganite perovskite, which had an oxygen capacity as high as the original ore but presented potential advantages in terms of enhanced kinetics, chemical and mechanical stability and the rate of methane conversion.…”