STJGAK-CANE JUICE CLARIFICATION. 11 



Loss in the infusorial earth process when the cake is washed, 3 gallons 

 of sirup, or $8. 



A fair estimate is that 25 gallons of sirup would be saved on an 

 average per 50 tons of cane. At $1 per gallon this would be a saving 

 of 50 cents per ton. Thus the increased cost of this process is well 

 offset by the reduction in the amount of sugar lost and in the cor- 

 responding increase in the yield of sirup. 



It remains to compare this method of clarification for sirup mak- 

 ing with that in general use in Louisiana. Here the changes required 

 for the introduction of this process would not be so great as in the 

 other sirup-making regions with which the comparison has been 

 made. In Louisiana the filter press is an indispensable part of the 

 factory equipment, being in general use throughout the sugar- and 

 sirup-producing section of the State. As practically all of the sugar 

 factories and many of the sirup factories are fully equipped with 

 presses, little or no change would be necessary in altering the equip- 

 ment for infusorial earth clarification. Eighty square feet of filter 

 press area per ton-hour is sufficient for filtering the whole cane juice 

 with infusorial earth. The cost of manufacturing sirup by this new 

 process would be practically the same as that of the lime and sulphur 

 process, since fuel and labor costs would be about the same. The 

 cost of the clarifying materials would be somewhat more in the 

 infusorial earth method, as shown below: 



Cents. 



Infusorial earth, 11 pounds per ton, at 2 cents 22. 



Against — 



Lime, 2i pounds per ton, at 1 cent 2. 5 



Sulphur, 1.4 pounds per ton, at 41 cents 6. 3 



Total 8. 8 



As shown above, the cost of the clarifying materials is somewhat 

 greater, but this is more than offset by the smaller amount of sucrose 

 lost in the process of manufacture owing to the ease and thorough- 

 ness with which the press cake can be washed. Another advantage is 

 that there is no need for settling tanks, skimming tanks, bag filters, 

 or other clarifying equipment in addition to the filter presses, since 

 the juice as it comes from the presses is ready for immediate evapora- 

 tion to sirup without further treatment. 



The only loss of sugar in a well-managed sirup or sugar house in 

 Louisiana after the juice has been extracted from the cane is in the 

 filter-press mud. Here it is figured that 36 pounds of press cake 

 of an average sugar content of 6 per cent are produced per ton of 

 cane, i. e., a loss of 2.16 pounds of sugar, or 0.27 gallon of sirup. 

 Figured on a basis of $1 per gallon for sirup, this is a loss of 27 

 cents per ton. 



