LIME AND CEMENT INDUSTEIES 



657 



containing an excess of moisture also tend to split in burning. 

 About Vf> of water is the proper amount. Magnesia is not spe- 

 cially objectionable except when silicates are present in the stone. 

 It causes difficulties, however, in the purification of the sugar 

 juice; consequently it should be at a minimum. Sulfate of lime 

 may act the same as magnesia. 



If silica is present, part of it passes into the juice with the 

 lime and retards the filtration process by coating the cloths in the 

 filter press. Silica also forms part of the scale on the heating 

 surface. There is less harm from this source in hard than in 

 soft stones. Silica and alumina also tend to form an insoluble 

 coating on the burned lumps which interferes with the slaking. 



The following analyses together with most of the above in- 

 formation on the stones used are from a report on the beet 

 sugar industry of the United States dep't agric, 1897, p. 205. 





1 



a 



3 



7.25 



4.9 



1.87 



3.3 



27 



81.67 



.59 



'\65* 



4 



5 



6 



7 



8 



9 



10 





4.1 

 4.5 

 1.2 

 2.1 



.37 

 85.86 

 .95 

 .05 

 .87 



5.1 



5.15 



1. 7 



1.75 



.41 



85.12 



.47 



.06 



.77 



4.15 



2 15 



1.05 



1.05 



.17 



90.13 



.75 



.1 



.45 



4.17 



3 07 



.97 



.98 



.19 



88 65 



.95 



.01 



1 



6 25 



8.17 



1.12 



.64 



.15 



87.93 



.5 



5.16 



2.25 



.86 



.56 



.a 



90.03 

 .45 



.52 



2.85 



.3 



.06 



.32 



93.8 



1.81 



1.21 

 .55 

 .41 

 .2 

 .23 

 96.58 

 .5 



.32 



.11 





.27 



Iron and alumina oxid 

 Lime carbonate 

 Magnesia carbonate. . 



.15 

 .03 



99.1 





.24 



.39 



.34 



.81 



Of the above nos. 1, 2, 3, and 4 are considered bad; 5, 6 and 

 7 are passable; 8, 9, 10 are excellent. No. 3 was used in a sugar 

 factory and caused trouble, notably " scaffolding " or difficulty in 

 the mechanical filters. No. 9 was substituted and these difficul- 

 ties disappeared. 



In looking over the analyses of limestones given in this report 

 it will be observed that limestones of as great purity as nos. 8, 

 9, and 10 in the foregoing table are not uncommon in New York 

 state. There are at present two beet sugar factories in New 

 York state, the one at Binghamton and the other at Rome. 



The following are some additional analyses of limestones used 

 in beet sugar manufacture. Nos. 1 and 2 of stone used at Los 

 Alamitos (Cal.), and no. 3, a French stone. 



