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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![properties and substances therein, so that after its discharge into said river it shall not create a nuisance which might endanger the public health. A chemical precipitation plant was duly installed in 1890, but the condition of the river remained bad. In 1895 Millbury brought suit against Worcester on the ground that the act of 1886 had not been complied with. After full expert discussion it appeared that the condition of the. river was in part due to the past pollution which had for years accumulated in its bed as sewage mud, and in part to the imperfectly purified chemical effluent still being dis- charged. The courts declared that the city had acted in good faith in attempting to carry out the act of 1886, but ordered that it should take further steps to comply with its provisions. Since that date sand areas for intermittent filtration have been progressively added for the final purification of the chemical effluent. It is possible in this case that chemical treatment is the best available preliminary process, since the city sewage contains free sulphuric acid and sul- phate of iron from the wire works which aid the chemical process and perhaps interfere with bacterial action. In 1904, 4,622 million gallons of sewage were received at the Worces- ter works, of which 4,227 million gallons were treated chemically. Six hundred million gallons of the chemical effluent and 395 million gallons of raw sewage were treated on sand filters. Lime is the only precipitant used, in the amount of 120 parts per million, sufficient iron being already present in the sewage to complete the reaction. For every million gallons of sewage treated 5,756 gallons of wet slur'ge are obtained, containing 6.93 per cent of solids. After pressing, this is reduced to 5.7 tons of pressed sludge containing 28.9 per cent of sohds. The cost of pressing and sludge disposal amounts to over $5 per miUion gallons. The analyses of sewage and effluent from 1894 to 1904 show that the yearly removal of the total albuminoid ammonia has varied from 46 to 63, averaging 52 per cent; of total oxygen consumed from 37 to 59, averaging 51 per cent; of suspended albuminoid ammonia from 83 to 98, averaging 93 per cent; and of suspended oxygen consumed from 77 to 89, averaging 82 per cent (Worcester, 1905). The results for 1904 are shown in Table IX. Table JX.—Resvlts of chemical precipitation at Worcester, Mass., I9O4. {Worcester, 1905). [Parts per million.] Material. Nitrogen as- Oxygen consumed in 2 minutes' boiling. Free ammonia. Albuminoid ammonia Total. Soluble. Total. Soluble. Kaw sewage 15.9 . 14.4 6.8 3.4 2.5 3.1 96.9 54.2 59.7 43.1 Chemical effluent .. IRK 185—06-](https://iiif.wellcomecollection.org/image/b21358205_0039.jp2/full/800%2C/0/default.jpg)
