Improvements in Process for Making Superphosphatic Manure.
Year: 1891

page_text: Date of Application, 21st Mar., 1891-Accepted; 23rd May, 1891
COMPLETE SPECIFICATION.
Improvements in Process for Making Superphosphatic Manure.
OTTO JAEHNE, Doctor Philosophiae, of Vienenburg, am Harz, in the Empire
of Germany, do hereby declare the nature of my said invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement :-
This invention relates to a new process or method for making superphosphatic
manure and consists in treating raw ferriferous phosphates with a weak solution of
bisulphate of sodium and in subsequently eliminating the gypsum from the solution,
which is then condensed through evaporation, to a salt that will be found to consist
principally of natrium sulphate and monocalcium phosphate. As an alternative
method I take a mixture of ferriferous phosphate flour, bisulphate flour and water,
allow this mixture to harden, afterwards grinding the product which contains
sulphate of natrium, phosphate of monocalcium and gypsum.
As a suitable ferriferous phosphate I prefer to employ caprolithen a compound of
which the following is an approximate analysis
50-2% of neutral phosphate of calcium.
8.8% of carbonate of lime.
15.0
%
of ferric oxide.
10% of argillaceous earth.
20.0
% hydrate of silica and silicates.
5.0° various matter.
:-
Of this compound I take 1 part to each 1-6 parts of bisulphate and 1 part of
water, grinding if necessary, and mixing to an homogeneous pulp which soon
becomes solid through the gypsum separating, while the bisulphate splits up into
natrium sulphate and sulphuric acid and the latter splits the neutral phosphate of
calcium in gypsum and monocalcium phosphate. The application of bisulphate for
treatment of phosphates in lieu of sulphuric acid permits of a great surplus of the
former without risking that the pulp would not become solid. A surplus of
sulphuric acid freed from bisulphate hinders or prevents the return of soluble
phosphoric acid through combination with iron and the natrium sulphate absorbs
the monocalcium phosphate and forms the salt above described and of which the
formula may be thus rendered 2 Na 2 SO4 + (СаH P₂O2 + H₂0).
product thus obtained reserves therefore the larger part of the originally applied
phosphoric acid in soluble form and consists in gypsum neutral sulphate of soda
and monocalcium phosphate.
The
When crushed it may be used as superphosphatic spreading powder in stables
and like places for the purpose of binding the nitrogen in the manures.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
The improved process or method for producing superphosphatic manure, consist-
ing essentially either in treating raw ferriferous phosphates with a solution of
bisulphate, eliminating the gypsum, evaporating the liquor thus producing a solid
salt which is the phosphatic manure, or in mixing ferriferous phosphate, bisulphate
and motor in such nrañantions that when fuel-

page_text: solid mass which can be ground to a fine powder and constitutes a phosphatic
manure.
Dated this 12th day of March 1891.
C. R. BONNE & Co.,
Authorized Patent and Trade Mark Agents, 57 & 58, Chancery Lane.