SEPARATORS, ONE OF WHICH IS OPEN—SHOWING THREE SCREENS FOR SEPARATING THE SUGAR GRAINS
The upper screen, called the scalper, is quite coarse and allows all the sugar to fall through except the lumps, which run down the face of the screen into a pipe that carries them to the melt, where they begin the refining process over again. These lumps, however, represent a very small proportion of the whole.
The second screen is finer than the scalper. It permits part of the sugar to pass through, but retains a certain amount which falls down on the face of the screen, whence it is led through a pipe to a special bin. Sugar of this size is known as coarse granulated.
The next screen lets the finer grains drop through, but catches the standard granulated, which in turn is drawn off to its special bin. The last screen, an extremely fine one, retains the extra fine granulated, and this in turn is delivered to its appointed bin. The sugar passing through the last screen is so fine as to be classed as “dust,” which, not being marketable, is usually remelted.
The amount of any one grade of sugar obtained from the separator may be changed, within certain limits, by the boiling in the vacuum pans. If a large proportion of fine-grained sugar is required, the sugar boilers are instructed accordingly. It is impossible, however, to boil all the grains in each strike a uniform size, or to boil any two strikes exactly alike, so the separators are necessary, especially for removing the lumps and dust. The dust is caused by the constant falling of the dry sugar crystals against each other in the driers and granulators, and by the grinding action upon the sugar crystals in the screw conveyors.
PACKING
FILLING VARIOUS KINDS AND SIZES OF CONTAINERS
When putting up his goods, a sugar refiner—like every other manufacturer—must needs cater to the wishes and tastes of the consuming buyer. The modern tendency in containers is in favor of sealed air-tight and dust-proof packages. Some refiners spend great sums of money every year in advertising the merits of special sugars packed in dust-proof cartons. Their rivals generally follow suit, as competition in the marketing of sugar is probably far keener than in any other line of business.
The plain truth is that all refined granulated cane sugar offered for sale in the markets of this country today is almost identical, irrespective of the manner in which it may be packed. The poorest quality of refined sugar made has, in all likelihood, a purity not lower than 99.5 per cent, while the highest grade cannot possibly exceed 99.9 per cent, a difference of only four-tenths of one per cent, hence it is evident that all refined sugars are practically pure, the fancy package simply meaning a fancy price.
The methods of transporting and handling the sugar after it leaves the refinery may justify the additional expense, but this is subject to argument. However, it makes but little difference to the manufacturer, as the cost of the package as well as the extra handling is always included in the selling price.