Specification of Henry Young Darracott Scott : treating sewage.

  • Scott, H. Y. D.
Date:
1873
Catalogue details

Licence: Public Domain Mark

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

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    Scotfs Improvements in Treating Seivage, $*0. tlie same is to he performed, to be particularly described and ascertained in and by the following statement (that is to say) :— The object of this Invention is the economical and inoffensive treat¬ ment of sewage and night soil. The process essentially consists in the utilization of the deposit (obtained from liquid sewage by the lime 5 method of precipitation) for the deodorization of night soil and the retention of its fertilizing elements. In carrying out my Invention I precipitate the sewage with lime in the usual manner. The deposit thus obtained is collected and dried in any convenient manner or by means of any suitable apparatus, but 10 with the view of preventing nuisances I sometimes mix with the wet deposit a small quantity of free lime, and in order to retain the ammonia set free in the drying process I lightly cover the wet deposit with some substance which has been impregnated with sulphuric or hydrochloric acid, but which does not neutralize the acid employed. I may use 15 sulphate of iron for a similar purpose, or chloride of iron will effect a similar result. Sawdust, hay, or straw answer very well as substances which may be impregnated with the acid or salt containing the acid which is used to fix the ammonia, but I may also use vegetable charcoal or dried horsedung or shoddy, or other refuse substances for this 20 purpose; the object being merely the employment of a vehicle for the acid, and in so far as this vehicle contains nitrogenous matter it will be better suited (of course) to enrich the deposit. The deposit may be dried on hot floors, or when previously compressed into cakes or allowed to consolidate spontaneously the deposit may be arranged in layers in 25 drying chambers together with the acidified substances above referred to, and be there desiccated, or it may be dried by simple exposure to currents of air in any suitable apparatus. The desiccation may be carried to the point of scorching when the size of the town is such as to justify the use of special apparatus for this purpose. In such cases the 30 ammonia evolved from the drying or scorching mass may be collected by well known methods. Tor small places simple air drying may be employed. The deposit may for instance be spread over a porous surface and be lightly covered with the acidified matters above referred to in order to retain the ammonia which would otherwise escape. 35 When the deposit has been dried, or dried and scorched it is to be reduced (in the generality of cases) to a powder (if this has not been i