The Jewell Gravity Filter.
Among the several systems in use for the mechanical filtraion of water is that known as the Jewell Gravity Filter, illustrated herewith, which, while it has been before the public for comparatively few years, has been quite extensively adopted, especially where large quantities of water were to be treated, as in public water-works systems, paper mills, and other large manufacturing establishments.
The tanks of these filters are made of cypress wood, for which material the advantages are claimed that it is practically indestructible in water, is less expensive than steel, and, as the tank can be shipped to its destination “knocked down,” will facilitate the erection of the latter in places where it would be a difficult task to put up one of metal.
Among the claims in favor of the general character and operation of the device are that most of the impurities are restained near the surface of the filtering medium, and that, consequently, the quantity of water needed to wash the filter is reduced to a minimum ; also economy, in that the filtering medium does not require to be replenished, the impurities being washed away at regular intervals of time by simply reversing the flow of water.
There are now in operation Jewell filters of an aggregate capacity of upw-ards of 25,000,000 gallons daily capacity, serving not only to clarify muddy water and remove suspended impurities, but also to eliminate bacteria or other micro-organisms, and to free water for boiler use from lime and magnesia. It is claimed that this filter will develop results identical with those obtained in the laboratory, freeing water from organic impurities, objectionable gases and minerals held in solution, if in conjunction with the filter proper, there is used a re-agent suited to the specific work to be performed.
The sizes in which the filters are made vary from 6 to 12 feet diameter by 14 feet height, with capacities ranging from 125,000 to 500,000 gallons daily. A 2,000,000 gallon battery is now being erected for the American Wood Paper Co., divided between its mills at Spring City and Manayunk, Pa. This company has already had the system in use nearly two years. A battery of gravity filters of 1,000,000 gallons capacity was also recently put in at the works of the Kalamazoo Paper Co., Kalamazoo, Mich., and one of like capacity is now in course of construction for the Bardee Paper Co., Otsego, Mich.
These Biters are manufactured by the O. H. Jewell Filter Co., No. 73 to 75 West Jackson street. Chicago, and the Morison-Allen Co., No. 145 Broadway, New York. A system of pressure filtration is also controlled by the same manufacturers.