194 



CHAPTER XI 



of o • 301, and remembering that for each decrease in the volume of the bagasse 

 an equal volume of juice is expressed, there will be 0-00855 lb. fibre and 

 0-01070 lb. juice, making the percentage of fibre 45-1. Hence under the 

 general equation H^P = k, as expressing the behaviour of bagasse on com- 

 pression, it follows that doubling the quantity of material and expending 

 the same work, the fibre in the compressed material falls from 50 per cent, 

 to 45 • I per cent. 



The writer does not wish to be taken as meaning that the numerical 

 values selected are necessarily accurate, though he believes they are of the 

 general order of what occurs in practice. They are introduced chiefly to 

 give a concrete expression to the formulae deduced from experiment. Three 

 points stand out, however, upon which reliance can be placed : First, great 

 increases after a certain limit in the hydraulic load on mills will not be accom- 

 panied by any but small differences in the composition of the bagasse : 

 secondly, after the fibre content of the bagasse reaches a certain figure 



Fig. 82 



a very great ' consumption of power is required to further reduce it ; and, 

 thirdly, very great increases in the quantity of cane milled are not accom- 

 panied by very large differences in the composition of the bagasse. In 

 other words, the capacity of a milling plant, between the limits of what is 

 considered reasonably good work and the very best work, is very great ; that 

 is to say, a milling plant is a very elastic machine. 



Power required to mill Cane. — With the results discussed above may be 

 compared others giving the indicated horse-power developed by mill engines 

 in actual operation, as found by the writer. ^^ 



Cane Carrier, Crusher and Mux, 34-in. x 78-in., working at Rate of 50 Short 

 Tons Cane per Hour with 12-7% Fibre, with Hydraulic Load of 400 Tons. 



H.P. H.P. 



Indicated H.P. per ton-cane-hour. per ton-fibre-hour. 



Max. 218 ... 4-36 ... 34-^ 



Min. 166 ... 3*33 ••• 26- ^ 



Mean 184 ... 3-68 ... 28'9 



