- 6 - 



The limes, however, were far from being saturated with CO2. Anal- 

 yses performed on lime from the same lots, but placed in scrubbers dur- 

 ing the 1964-65 storage season, showed that after 1 month of use in a 

 dry lime scrubber, a composite sample from 1 bag each of limes B, C and 

 D had CO2 equivalents of 10.5%, 16.9% and 22.9%, respectively. At the 

 end of storage, these limes had CO2 equivalents of 23.0%, 21.4% and 

 37.5%, respectively. Bags of lime from the same lot as lime A had CO-, 

 equivalents of 25-30% at the end of the storage period. Consequently, 

 even though considerable COp was absorbed during a year's storage of 

 these limes, they would still have been of value for scrubbing. 



Further Tests Conducted in 1965-1966 



To further test the value of other than "fresh" lime for scrubbing, 

 the carbon dioxide contents of 3 types of lime in a dry-lime scrubber 

 were compared to those of similar types of lime stored outside the scrub- 

 ber during the 1965-66 storage season. The limes inside and outside the 

 scrubber were sampled at monthly intervals from November through March. 



For simplicity, only the data obtained from the analyses of a high- 

 calcium hydrated lime are presented in Table 2, but data obtained for 

 the other 2 types of lime (a hydrated dolomitic lime and a dolomitic 

 spray lime) were similar. 



Table 2. Carbon dioxide absorption of lime in a dry-lime scrubber in 

 comparison to similar lime stored outside of the scrubber 



Carbon dioxide content of lime 



^ 



Outside scrubber 



Composite 

 sample*^- 



Top of 

 bag 



% 



2.4 

 2.0 

 4.7 

 3.9 

 3.1 



% 



2.4 

 13.7 

 17.3 

 16.5 

 15.7 



%igh-calcium hydrated lime - (CaO, 72-74%; MgO, 0.2-0.6%). Bags placed 

 vertically inside and outside of scrubber. 



Lime sample obtained with a sampling tube thrust diagonally 3 times 

 from top to bottom of bag. 



It is apparent from Table 2 that in the bags stored outside the 

 sci'ubbor, no appreciable change in CO2 content occurred other than sur- 

 face absorption by the lime. These data substaiitiate the data presented 

 in Table 1 and indicate that other than fresh lime would be of some value 

 for CO2 removal. 



