Other Processes and their Potential

The APM mill at Bumie, Tasmania used the soda process to obtain bleachable grade pulps from euealypts for the manufaeture of fine papers, but in 1983 the mill switched to the soda-AQ proeess in order to pulp pine and euealypts together, the deeision being made on the grounds of wood availability. 

The soda-AQ proeess ean use the same ehemieal recovery system as for kraft pulping but is teehnieally well suited to a simpler, more compact system known as DARS (direet alkali reeovery system), whieh has been explored on the pilot plant seale. Here ferrie oxide is added to the blaek liquor in a fluidized bed furnace. The residue of sodium ferrite partieles is removed and on leaching under controlled eonditions regenerates sodium hydroxide and ferrie oxide  

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