. The sanitation of cities. BALTIMORE, MARYLAND Sewage treatment plant, showing two cylindrical screens for treating the sewage after passing through tanks prior to entering filter beds aerobic bacteria under control, and in the presenceof a plentiful supply of oxygen. The standard methods now used are all sec-ondary forms of treatment; that is, the sewage hasalready passed through a stage of preparation bywhich suspended solids have been removed to agreater or lesser extent. Examples are shown inthe accompanying illustrations of the variousforms of plants used for the purpose. It would be use
. The sanitation of cities. BALTIMORE, MARYLAND Sewage treatment plant, showing two cylindrical screens for treating the sewage after passing through tanks prior to entering filter beds aerobic bacteria under control, and in the presenceof a plentiful supply of oxygen. The standard methods now used are all sec-ondary forms of treatment; that is, the sewage hasalready passed through a stage of preparation bywhich suspended solids have been removed to agreater or lesser extent. Examples are shown inthe accompanying illustrations of the variousforms of plants used for the purpose. It would be useless to attempt a detailed com-parison of the methods of secondary or oxidationtreatment. The installation of such plants is sel-dom really necessary, and much public money hasbeen uselessly expended in the futile attempt to 99. 100 ^be purification of Sewage make drinking water out of sewage. The real andusually the only requirement is to prevent anuisance in a stream or waterway the use of whichis unavoidable for sewage discharge. In Chicago a few years ago, a board of consult-ing engineers considered various plans for thesewage disposal of that city. One of these plansconsisted of primary and secondary treatment bymeans of tanks, followed by sprinkling filters ofimmense size and capacity; the other was for acanal connecting the waters of Lake Michiganwith the Illinois River, thereby creating a greatcommercial waterway, into which the entire sew-age of the city could be discharged, and com-pletely treated by the mere dilution thereof, withthe waters of the canal.
Size: 1193px × 2094px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, bookidcu3192400497, bookyear1921
