Water Softening and Purification: The Softening and Clarification of Hard and Dirty Waters |
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Common terms and phrases
alkaline bicarbonate boiler compositions carbonate of lime carbonate of magnesia carbonate of soda carbonic acid caustic soda cent chalk chemical chloride of calcium chloride of magnesium clean CO₂ coal cold water colour condensed corrosive cost crystals cubic centimetre decomposed degrees of hardness deposit diaphragms dilute dissolved distilled water dyeing economiser effect evaporated exhaust steam feed water filter flues frequently furnace gallons of water grains per gallon greasy hard scale hard water heat heater hydrate of lime impurities insoluble iron lime and magnesia lime process lime water method methyl-orange mud cock neutralise oxide phenolphthalein plates potash alum precipitate present pressure proportion quicklime reagent removed sea water settle slaked soap solution soap test soft water softening process soluble STANHOPE strength sulphate of alumina sulphate of lime sulphate of magnesia supply surface condenser tanks temperature thousand gallons towers TOWN WATER tubes washing water contains water softening Water-tube boilers
Popular passages
Page 136 - The process presents so many advantages, and is so simple, that we are surprised not to see it in general use, and naturally expect to find on investigation that it has some great drawback. This, however, does not appear to be the case.
Page 112 - Quantity of substance that one English * gallon of pure water can dissolve. * For an American gallon reduce each amount by 16.7 per cent, t Insoluble at about 290° F. t Decomposes at boiler temperatures in presence of alkaline earths or iron. § Insoluble at 302° F., equal to 70 Ibs. steam pressure. Chemical Analysis. — Many times when we are away from the large business centres it is desired to test the...
Page 135 - 2. Water, the hardness of which is wholly or chiefly of the temporary kind, may be easily, cheaply and efficiently softened, on the large scale, by the proper use of lime, and the wholesomeness and palatability of such water are sometimes increased, and never diminished, by the process. " 3. The lime method of softening may be applied with ease and great economy to the whole supply of even the largest towns, provided the hardness of the water be wholly or chiefly of a temporary kind. " VII. As to...
Page 2 - Temporary hardness is due to the carbonates of lime, magnesia and iron ; the precipitation and removal of these begin at temperatures below the boiling point, and is practically completed by continued boiling at atmospheric pressure. Permanent hardness is due to the sulphates, chlorides and nitrates of lime, magnesia and iron, which, as a rule, are not precipitated or removed at temperatures below the boiling point. Another group of the soluble impurities in water, those which cause corrosion, includes...
Page 135 - ... carbonates of lime and magnesia (temporary hardness), may be softened either by boiling for half an hour, or by the addition of a proper quantity of slaked lime. Except the last, all these processes are expensive, and inapplicable on the large scale. 2. Water, the hardness of which is wholly or chiefly of the temporary kind, may be easily, cheaply and efficiently softened, on the large scale, by the proper use of lime, and the wholesomeness and palatability of such water are sometimes increased,...
Page 146 - ... still hard, the lather will break up and disappear. More soap should then be added in small quantities, and the bottle shaken after each addition until a lather is formed that is sufficiently permanent to last for several minutes. The number of cubic centimeters of soap solution added to the water, less one, indicates the hardness of the water in degrees. One degree is deducted because even distilled water requires a slight quantity of soap to make it lather. 23. Standard Soap Solution.
Page 146 - ... being determined in parts per 100,000, 100 cubic centimeters of water is used, and each milligram of water corresponds to 1 grain or part per 100,000. 22. The soap test is applied in the following manner: 70 cubic centimeters (or 100 cubic centimeters, as the case may be) of the water to be tested is placed in a clean glass bottle large enough to hold two or three times that quantity. A clear solution of soap of standard strength is then gradually added to the water, and the mixture briskly shaken....
Page 87 - A coating of scale is ah efficient protection against the corrosive action of the chlorides of lime and magnesia when it covers every part of the boiler. In this case the hydrochloric acid attacks the scale instead of the iron. But a coating of scale is seldom sufficiently continuous to protect all parts of the boiler, as scale is liable to crack and the iron, thereby exposed, is at once attacked and corroded until covered by new scale. The presence of air in feedwater is known to have a very injurious...
Page 113 - The figures do not indicate the weight of chemical contained in a gallon of saturated solution.
Page 162 - ... gallons of water evaporated per hour. 1 indicated horse-power requires in small noncondensing engines from 3 to 10 gallons of water evaporated per hour.