Specification of John Hanson : treating sewage.

  • Hanson, John
Date:
1875
Catalogue details

Licence: Public Domain Mark

Credit: Specification of John Hanson : treating sewage. Source: Wellcome Collection.

    7/10 page 5
    Hanson's Improvements in Treating Sewage. birds have died a natural death, it may he by long age, starvation, or disease. The same can be supposed of the bone supplying animals, therefore I am convinced that diseases are from these sources imported into our country. The manures are spread upon our fields, our plants 5 feed upon those manures, and our cattle feed upon those plants, thus acquiring diseases that were previously foreign to them. From a sanitary and commercial point we find that the importation of manures is an evil, and must be discontinued, especially when we are continually making millions of tons of manure hitherto wasted, the 10 residuum of sewage and foul water. In carrying my Invention into practice for the precipitation of. the sludge from each one hundred thousand gallons of sewage water (and this part of my Invention is also applicable to the precipitation of all foreign deleterious or poisonous particles or matter suspended in foul waters, such 15 as those issuing from dye works and other factories or works in order to effect their purification), I take of slacked lime (say) about 20 to 23 lbs., and of soot or of flue dust about ya lb., and of black ash about 30 lbs. (the last-named ingredient being the residuum from alkali works), and these precipating ingredients (the proportions of which may vary) I 20 thoroughly grind, mix, and incorporate together, and I make them into a cream-like paste and run them as thus combined into the supply pipe forming the communication between the sewage pumping well and the settling tanks, or otherwise in the most practicable form, so as effectually to mix with the sewage mass as or before it passes into the 25 settling tanks for precipitation. I employ these precipitating ingredients preferentially because they combine the advantages of being comparatively inexpensive, and as being among the best precipitants and deodorizers known, the lime giving a clear transparent effluent, the brackishness of which, owing to 30 the suspended hydrate of lime, which would render it unfit for manu¬ facturing or domestic purposes) is effectually neutralized by the car¬ bonizing effect upon the lime of the black ash, which latter is a most powerful absorbent of oxygen, and the carbonic acid gas collected by the lime is also thus set free, and the water is consequently neutralized 35 and restored to its natural state of purity. Moreover the black ash (from such works as above mentioned) contains about 90 soluble salts and about 10 of charcoal and earths. These salts contain muriate of soda and potash, sulphate of potash and muriate of lime, and also
    digitised image 1
    digitised image 2
    digitised image 3