This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
The object of boiling water is to remove or destroy any orgauic impurities - disease germs or microscopic life - that would injure health. While it no doubt does have a beneficial effect, still we believe that recent investigations have shown that certain germs are capable of resisting the heat of boiling water; however, we may be assured that the bulk of animal and vegetable matter has been coagulated, and can be removed by subsidence or filtration.
Boiled water tends to remove also by subsidence a great many inor-ganic compounds, such as oxides of iron and manganese, lime, magnesia and silica. These compounds are often a great annoyance to users of steam, as they form that familiar and objectionable deposit known as "boiler incrustation" on the interior of boilers. By boiling water all oxygen and natural carbonic acid it holds absorbed are expelled. This, in connection with the removal of certain salts by subsidence, renders boiled water, even when cold, flat, insipid and mawkish, and remains so until it has become aerated by exposure to air or by special means, or until it has become carbonated. If the water is boiled one hour it is completely sterilized; ordinarily, a much shorter time suffices to make it safe to drink.
Whenever it is necessary to use for drinking purposes a water suspected to be impure, it should always first be boiled thoroughly; and since boiled water is insipid to the taste, it may be flavored with tea, or some other harmless substance. When used for carbonating it will be an advantageously clean water and answer all purposes if previously filtered.
The main difficulty in carrying out the operation of purifying the water by boiling on an extensive scale is the subsequent cooling and the cost of the arrangement. Where steam is available, one of the most simple systems for boiling water is by means of the coil and vat here shown.
At the upper end is connected the steam pipe from the boiler, and the outlet is at bottom. As the water runs into the vat the steam is turned on, and by the time the vat is filled the water is nearly boiling; the boiling water is then run out from the connection at side of vat, fixed about three inches from the bottom, and is carried by means of tin pipe to a cistern, where it is allowed to cool and precipitate the coagulated impurities, before it runs through the filter. If the quantity of water necessary in an establishment is small, or if several steam-vats are employed, the cooling and precipitating may be allowed to go on in the vat itself after steam is turned off, and afterwards the whole contents should be run through a filter. Cover the vat while cooling to prevent impurities from falling in; it will take longer, however, but it is a wise precaution. Clean and rinse out the vats from precipitates carefully before boiling again.
The vat is made of best oak, very thick, and bound on its outer side by galvanized iron hoops; the coil is made of strong block-tin tube. It It has suitable connections for taking steam pipe at outlet, where the condensed water escapes.
The average time for boiling 100 gallons of water is from twenty minutes to half-an-hour.
This apparatus is designed for giving pure water, as the water can be boiled first, then passed through the filter and thence to the fountains. The same apparatus can also be used to warm the building.
Fig. 10. - Steam Vat and Coil.
The cut represents the apparatus as used in bottling establishments. The boiler can be placed on the same floor with open tank, or on the floor beneath, but the tank must be elevated above the top of boiler. The flow-pipe must not turn downward or trap be ween the tank and boiler.
Fig. 11 - Weathered's Quick Heating Apparatus.
The lower draw-off pipe must be above the line of flow connection from boiler. The supply of cold water is regulated by a supply pipe and ball-cock. The water may come from the hydrant, an elevated cistern, or be taken from a well by the aid of a pump. The openings of boiler are for two-inch pipe, but can be reduced to any size required. The boiler is easily set up as a common stove. 125 to 700 gallons of water, according to size, can be heated to boiling per hour.