SUGAR-CANE SIRUP MANUFACTURE at 
operate the mill and for evaporation, the application of the process 
would call for very little additional equipment. 
Little alteration of equipment for infusorial-earth clarification 
would be required in those Louisiana sirup factories which are pro- 
vided with filter presses. The cost of manufacture would be prac- 
tically the same as that by the sulphur-lime process, as the total fuel, 
labor, and overhead costs would be very nearly identical. The cost 
of the clarifying materials would be somewhat greater in the infusorial- 
earth method, but this is partly offset by the smaller quantity of sirup 
lost during manufacture. Another advantage of the infusorial-earth 
method is the elimination of juice-settlng tanks, skimming tanks, 
bag filters, and similar equipment. 
The principal loss ef sirup or sugar, after the juice has been ex- 
tracted from the cane, in well-managed Louisiana sirup or sugar- 
houses using the sulphur-hme process and equipped with filter 
presses, 1s In the filter-press mud. Approximately 36 pounds of filter- 
press cake, with an average sugar content of 6 per cent, is produced 
per ton of cane, a loss of 2.16 pounds of sugar, or 0.27 gallon of sirup. 
Calculated on a basis of $0.50 per gallon for sirup, this represents 
a loss of $0.135 per ton of cane. In sirup factories where the sulpnur- 
lime clarification process is practiced without the use of filter presses 
the loss of sirup is estimated to be one-half to 1 gallon per ton of 
cane, or between $0.25 and $0.50 when sirup is valued at $0.50 per 
allon. | 
4 In infusorial-earth filtration, 40 to 45 pounds of filter-press cake 
per ton of cane may be expected. Considering the ease and rapidity 
with which this cake can be washed, there is no reason why the sugar 
content should not be readily reduced to less than 1 per cent. If 
washed to a sugar content of 1 per cent, the loss would amount to 
approximately 0.45 pound of sugar, or about 0.06 gailon of sirup per 
ton of cane. On the basis of $0.50 per gallon for sirup, this would be 
a loss of only $0.03 per ton. The difference in losses, $0.135 — $0.03, 
or $0.105 per ton of cane, or $0.25— $0.03, or $0.22 per ton of cane 
if no filter presses are used, would largely compensate for the greater 
cost of infusorial earth as compared with the cost of sulphur and lime. 
The materials required for clarification with sulphur dioxide and 
lime cost approximately $0.035 per ton of cane—$0.0075 for lime (1 
pound per ton of cane at $0.0075 per pound) and $0.0275 for sulphur 
(1 pound per ton of cane at $0.0275 per pound). 
The infusorial earth needed (12 pounds per ton of cane at $0.025 
per pound) costs $0.30. When the cane is of good quality less 
infusorial earth is required than when the cane is immature or has 
deteriorated after cutting. Factory tests have shown that from 12 to 
18 pounds of infusorial earth of good quality per ton of cane ground 
are required to give a satisfactory rate of filtration. 
In addition to the accessory tanks, pumps, and piping, filters either 
of the plate and frame or of the leaf type are needed for mechanical 
clarification. The filter press area should be ample, so that no inter- 
ruption in operation need occur. In order that poor-quality juice 
may be promptly filtered, the filter area installed should be somewhat 
im excess of that which would ordinarily be needed. Approximately 
8 square feet of filter area per ton of cane per 24 hours has been found 
sufficient to handle a slow-filtering juice, whereas 4 square feet per 
ton of cane per 24 hours has proved ample for free-filtering juice. 
