. Preventive medicine and hygiene. tes, and other powerfuloxidizing chemicals used in water purification. It is necessary to get the ozone out of thewater in order to avoid the corrosion of may be done by aeration, by means of foun-tains or cascades. On account of the insolubilityof the ozone, it soon disappears. The fact thatozone is largely insoluble in water makes it necessary to bring it intointimate contact with all portions of the water to be treated. This isusually accomplished by allowing the water to trickle doT^Tiward throughtall cylinders filled with coke, lava, or other
. Preventive medicine and hygiene. tes, and other powerfuloxidizing chemicals used in water purification. It is necessary to get the ozone out of thewater in order to avoid the corrosion of may be done by aeration, by means of foun-tains or cascades. On account of the insolubilityof the ozone, it soon disappears. The fact thatozone is largely insoluble in water makes it necessary to bring it intointimate contact with all portions of the water to be treated. This isusually accomplished by allowing the water to trickle doT^Tiward throughtall cylinders filled with coke, lava, or other similar substances whilethe ozone is admitted to the bottom of the cylinder. The Avater flowsdownward, the ozonized air works its way upward, and in that way thedesired contact is obtained between the ozone and every portion of thewater. A very small amount of ozone is effective for the purification ofwater. It only requires from 1 to 3 milligrams per liter. The modernmachines produce concentrations as high as 10 grams and more of. Fig. 112.—An Open tube throughwhich air is led. B andC are electrodes, sep-arated by the glasstubes D, between whichthe current of air pass-es. (After McPhersonand Hendersons ACourse in GeneralChemistrj^ publishedby Ginn and Co., , p. 31.) CHEMICAL METHODS OF PURIFYING WATER 899 ozone per cubic meter of air. The ozone not taken up by the watermay be used over and over again. This is accomplished in some of theozonizing processes by conducting the air that leaves the upper part ofthe water cylinder back to the ozonizer. In general, it may be said that, owing to the expense and the elec-trical and engineering difficulties involved, the ozonizing process isnot at present applicable to the purification of water upon a small has been applied with success upon a large scale in a number ofplaces. The first ozonizing apparatus for the purification of water ona large scale was installed by Siemens-Halske at Lille, France. Othero
Size: 1165px × 2145px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorwh, bookcentury1900, bookdecade1910, booksubjecthygiene
