Water Lifted By Compressed Air
For Municipal, Manufacturing, Irrigation or Other Water Supply

yearly, steam rate 22 1-2 pounds and evaporation of nine to one, as before. This would require annually coal amounting to 1,875 tons. Aciding 10 per cent., as before, for power to lift condensing water, gives as the total power 550 H. P. In this case we will only assume that the condenser brings the water rate down to 18 pounds, or a reduction of 20 per cent., giving a coal rate of 2 pounds per horse-power hour. Five hundred and fifty horse power at 2 pounds coal gives yearly coal required as 1,650 tons. Yearly saving in coal, 225 tons, or, at $2 per ton, 10 per cent, interest on $4,500—far more than the usual cost of equipping with compressor and condenser. No extra labor is required, as the compressor can be located in the engine room and looked after by the old force. But there is a saving of over 10 per cent, in the handling of coal and ashes and a reduction of the work required of the boiler plant. If an evaporation of 7 pounds of water per pound of coal is taken as the basis of figuring (and this is nearer the average) and the plant runs more hours per year, the saving can easily be made three times the above figures. Again, it is not usual that it would be necessary to lift the water as much as 75 feet vertically, as water suitable for this purpose can usually be found nearer the surface. Another instance of the material saving in fuel consumption as a result of pumping water especially for condensing purposes may be found in the experience of the Husted Milling Company of Buffalo New York. An 8-inch well was drilled to a depth of 325 feet, when a strong stream of water was reached. The water rose to such a height in the well that when pumping 400 gallons per minute the lift to the surface was 50 feet. It was quite cold, the temperature bein<- about 50 degrees, and so impure that it could be used for no other purpose than condensing. 1 This company had a 26x48-inch Corliss engine, the load on which was about 600 H. P. Steam was furnished by three return tubular boilers, two of 100 and one of 140 H. P. capacity. A low pressure steam cylinder, 52x48 inches, was added to the engine making it tandem compound. A jet condenser giving a good vacuum was also installed. Since this change, despite the fact that they have been compelled to reduce the steam pressure to 100 pounds on account of the a^e of the boilers, these same boilers are doing the same work, and in "addition are also furnishing steam for the condenser and to operate a 12 and (x 4-inch ( lass ‘A” Straight Line air compressor, which is used tor the Air Lift. Only one fireman of the two employed heretofore is now needed, while the coal consumption has been cut from 8 tons to less than 4 tons for a 15-hour day. The change has further resulted in increasing the H P. of the engine by about 150. Altogether the saving is summed up at from $3,000 to $3,500 per year.