TOLKE POLLUTION OF WATERS BY FACTORY REFUSE. 621 



A sugar factory using every day 400,000 pounds of beets and working 

 for 20 hours will, therefore, consume the following quantity of water per 



minute : 



Liters. Cubic feet. 



Washing the beets 83.33= 2.7 



Production of juice 370. 00 = 12. 



Condensation 1, 703. 33 = 55. 



Generating steam 250. 00 = 8. 1 



Purifying through carbonized bones 83. 33 = 2. 7 



Refining .' 41 . 0G = 1. 35 



Total per minute 2, 531. 00 = 81. 85 



A factory using anually 7,000,000,000 pounds of beets will therefore 

 consume the enormous quantity of 1,435,000 cubic feet of water. This 

 mass of water is taken either directly or indirectly from public brooks 

 and rivers, and after having been used is returned to them in slightly 

 diminished quantity, but having a temperature of some 40° Reaumur, 

 and containing organic matter and alkalies of every kind. 



The high temperature favors the disintegration of organic matter, 

 produces fermentation, oauses the formation of alga? and fungi, becomes 

 fatal to animal life, and fills the air with miasmatic effluvia. 



It is possible, however, without any detriment to the beet-sugar in- 

 dustry, to diminish the consumption of water by one-half, as has been 

 tried very successfully in factories where water was scarce. 



This saving of water is accomplished by — 



1. "Working the diffusing apparatus by compressed air instead of 

 water. By this means (always supposing a daily consumption of 400,000 

 pounds of beets) 191 liters, or 0.GG cubic feet of water are saved every 

 minute. 



2. By using for washing, generating of steam, and refining the con- 

 densed water from the two boilers, and thus saving 375 liters = 12.15 

 cubic feet. 



3. By regaining two-thirds of the condensed water from the boilers, 

 and by cooling the water to the temperature of the air by means of a 

 suitable apparatus, 1,135.5 liters, or 3G.G cubic feet of water are saved. 



The total saving per minute is, therefore, 1,205 liters ; i. e., one-half 

 of the quantity consumed. Practically, the saving may be less, but 

 certainly not less than one-fourth of the quantity consumed, i. e., 600 

 liters per minute. 



It is evident, therefore, that it would be a great gain if all beet-sugar 

 factories could be compelled by law to introduce the saving system. 

 There could certainly be no objection to this, if we consider that many 

 factories have to follow this system, simply because they have not enough 

 water. 



" Polluted waters," properly so called, must be carefully separated 



