Investigations on the purification of Boston sewage made at the sanitary research laboratory and sewage experiment station of the Massachusetts institute of technology, with a history of the sewage-disposal problem / By C.E.A. Winslow and Earle B. Phelps.
- Charles-Edward Amory Winslow
- Date:
- 1906
Licence: In copyright
Credit: Investigations on the purification of Boston sewage made at the sanitary research laboratory and sewage experiment station of the Massachusetts institute of technology, with a history of the sewage-disposal problem / By C.E.A. Winslow and Earle B. Phelps. Source: Wellcome Collection.
Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.
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![Another large American precipitation plant is that at Providence R. I., where since the sewage effluent is discharged into a tidal estuary the removal of suspended sohds alone is all that is necessary Pre- cipitation was recommended by S. M. Gray after an exhaustive mves- tigation in 1884, but the plant was not finally installed until 1902. Comparative statistics for the operation of the Worcester and Provi- dence purification works in 1903, copied from Fuller, are given m Table X. Table X.Statistics of chemical precipitation at Worcester, Mass., and Providence R I 1903 {Fuller, 1905 a). ' ' '' Population connected to sewers, estimated Average daily sewage flow, total million gailrns Average daUy sewage flow, treated ].] do Total annual sewage flow treated do Applied lime [pounds per million gallons. Igrains per gallon Applied copperas /pounds per million gallons. „ ... Igrams per gallon Gross capacity of basins million gallons Percentage of removal: Total organic matter by albuminoid ammonia Suspended organic matter by albuminoid ammonia Wet sludge: Average pressed daily gallons.. Percentage of total sewage flow Average percentage of dry solid contents !!!!!!!!!!! Average amount of lime added per 1,000 gallons _ pounds.! Pressed sludge cake S^°^^ ^f^V \percentage of dry solids.. Dry solids in sludge: Tons daily Tons per million gallons Tons per 1,000 population per annum Cost of sludge pressing and disposal: Per ton of dry solids Per million gallons sewage flow Cost of chemical precipitation (labor and supplies) per million gallons Total cost of operation: Per million gallons Per capita connected to sewers per annum Cost per ton: Lime Copperas Minimum wage per hour for laborers ^Vorces- ter. Provi- dence, o 122,000 15.55 14.39 5.250 871 6.1 0 0 5.5 170 ono 20.3R :o 7, :;flO 'bog 4.2 65 . 46 li.i 51.69 91.58 a 49. SO a 82.54 67, 200 .4671 7. 44 33.5 95,600 .4776 5. 37 23.6 76 28.25 69 30.3 20.80 1.45 62 21.40 1.07 46 $3.39 $4.91 S4.01 $2.27 $2. 44 83.31 $8.92 $0.384 $5.75 $0,248 $6.00 $6.90 $7.80 $0.23J 80.15 a Providence sewage well screened before treatment. Before leaving the subject of chemical treatment it will be well to refer briefly to certain special processes which have been suggested and adopted in exceptional cases without finding general application. For example, with the Liernur system of sewerage in use in certain Dutch and Belgian cities, which lie at too low a level for gravity sys- tems, the excreta diluted with a small volume of water are dra^TO off by suction through a system of tight sewers, and sewage of tliis type has been handled by direct evaporation, the residue being used as fer- tihzer. Its application is naturally hmited (U. S. Dept. State, 1895). The Degener process applied in some German cities involves mixture of the sewage with crushed lignite, precipitation with ferric sulphate, pressing of the sludge, and treatment of the effluent with bleacliing powder. The process is costly, but at Potsdam and Tegel is said to](https://iiif.wellcomecollection.org/image/b21358205_0040.jp2/full/800%2C/0/default.jpg)
