Manufacture of Sugar from Beet- Root. 



155 



to the drjing-house, which may consist of a series of wire trays 

 or shelves, or any similar arrangement through which a current 

 of dry air, of not less than 100° and not more than 150°, should 

 be passed. When quite desiccated they may be stored away as 

 they are, or reduced to a coarse powder, and will thus keep 

 unaltered for any time until they are wanted in the factory. For 

 use they must be ground, and the coarse powder be then mace- 

 rated in about 36 parts of boiling water, in which Schiitzenbach 

 recommends from 2 to 3 parts of sulphuric or sulphurous acid 

 should be mixed. It is generally arranged that the dried powder 

 shall be placed in a range of vessels of different levels commu- 

 nicating with each other, so that the water shall pass through the 

 uppermost, and dissolve out its contents previous to passing on 

 to the next. In this way a clear and more concentrated syrup 

 is obtained, thus effecting a great saving in the fuel and risks 

 consequent on the evaporation. This method (Schiitzenbach's) has 

 been condemned in many districts, on account of the increased expen- 

 diture required in buildings for the drying operation, and in the fuel 

 necessary for the evaporation of the 36 parts of water subsequently 

 added. In this country, where fuel is so cheap, and where desicca- 

 tion on a large scale is so constantly employed in manufac- 

 turing concerns, these objections, probably, would not have 

 much weight. 



We must now consider the various operations forming the 

 second part of the process. After having obtained all the avail- 

 able saccharine juice from the root by one of the foregoing 

 methods, the next operation is that of clarifying or defecating. 

 To effect this, several modes have been devised. The only one 

 which we think, however, necessary to give here is the lime pro- 

 cess, which is the simplest, the most general, and the most readily 

 understood and carried out.* The juice is placed in a large pan 

 (metal), heated by steam in the usual manner, and evaporated 

 down to a certain specific gravity ; a certain quantity of hydrate 

 of lime is then added, and the boiling continued until the whole 

 of the changes effected by the lime have taken place. These 

 changes are most important. The lime, uniting with the albu- 

 minous and gummy matters, forms insoluble compounds with 



^ * The process due to M. Melsens, in which acid sulphites, and more especially 

 bisulphite of lime are employed, is adopted in some districts on the Continent. 

 These salts effect a double purpose, checking feraientation by the presence of 

 sulphurous acid, and neutralising the sulphuric acid as fast as it is formed by 

 means of the lime. (See Phil. Mag. 1850.) 



A process very similar in its action was patented in 1849, by Messrs. Price and 

 Eeece, which includes the application of both acid sulphites and hyposulphites. 

 (See Eepository of Patents, No. 85.) 



In 1849, Messrs. Oxland patented a process for defecating and decolorizing 

 sugar, by means of acetate of alumina, &c. ; and in 1851, they took out a second 

 patent for the use of phosphoric acid in a state of combination with certain alkaline 

 bases for the same purpose. 



