Specification of Henry Young Darracott Scott : treating and deodorizing sewage water.

  • Scott, H. Y. D.
Date:
1866
Catalogue details

Licence: Public Domain Mark

Credit: Specification of Henry Young Darracott Scott : treating and deodorizing sewage water. Source: Wellcome Collection.

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    Scott's Improvements in the Treatment and Deodorization of Sewage Water. are to be provided with self-feeding hoppers for maintaining the filter beds in proper condition as the lime and iron salt is washed away. As regards certain modifications of the first portion of my process above described, in lieu of milk of lime prepared from fat limes which readily slake abroad I sometimes propose to use dolomitic limes or a lime compound of the nature of cements, which latter after calcination will not slake to powder; but if ground to a powder and mixed in with the sewage water will act to a certain extent in the same manner, and will give consistency to the sludge deposits. The latter compounds usually contain iron oxide which, in the presence of sulphuretted hydrogen, will slowly form sulphide of iron; they also contain substances useful as manure. Similar compounds may sometimes be used in pieces in lieu of the artificial lime compounds above described to form filters for the sewage matters. 15 In forming the artificial pieces of lime compound above described I some¬ times mix in ten or fifteen per cent, of sulpbate of lime, which will also control the slaking of the quicklime, or ten or fifteen per cent, of chloride of sodium, or five to ten per cent, of perchloride of iron, which will render the pieces more soluble, and will themselves act as disinfectants. Sometimes I add 20 five to ten per cent, of carbolic acid in manufacturing the pieces on account of its disinfecting properties. Instead of employing crystals of sulphate of iron for the second part of the disinfecting process I sometimes employ a compound of perchloride of iron, or of sulphate of iron and artificial gypsum made into pieces, which would be 25 less readily soluble than crystals of sulphate of iron. The beneficial effects of gypsum as a manure for certain crops is well known, and when the sewage is to be applied to irrigation the sulphate of lime would be found a useful adjunct. In the preparation of such pieces of artificial gypsum and iron salts I merely mix dehydrated sulphate of lime or plaster of Paris with a 30 solution of the iron salt in the right proportion to make a paste on solidi¬ fication. Carbolic acid or chloride of sodium may also be sometimes advantageously mixed with the paste from which the blocks or pieces of this compound are to be formed. Having now described my Invention of improvements in the treatment 35 and deodorization of sewage water, and having explained the manner of carrying the same into effect, I claim, as the Invention secured to me by Letters Patent as aforesaid, treating sewage water first with lime, and after¬ wards with metallic salts, as herein set forth.