Improvement in the Manufacture of Fertilizers.
Year: 1894

page_text: Date of Application, 6th Feb., 1894-Accepted, 10th Mar., 1894
COMPLETE SPECIFICATION.
Improvement in the Manufacture of Fertilizers.
We, JONAS JOSEPH SELDNER, of 1514 Eutaw Place, Baltimore Maryland,
United States of America, Merchant, and JOHN WATSON Junior, of 1519 North
Broadway, Baltimore, aforesaid, Lawyer, do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
The invention relates to the manufacture of fertilizers from refuse hair, fur,
feathers, leather and glue scrap and other similar material containing a large
percentage of nitrogenous substances. These substances have hitherto been largely
thrown away on account of the difficulty and cost of reducing them to marketable
fertilizers.
The object of the invention is to produce from substances of this class fertilizers
which are rich in ammonia and phosphates, and at an expense which is low in
proportion to the value of the product.
According to one method of carrying out the invention, the hair or other
nitrogenous scrap is placed in a vessel with a weak solution of some mineral acid,
usually sulphuric. This vessel or digester is then closed steam tight and heat
applied sufficient to vaporize the water in the acid solution and produce a steam
pressure of thirty pounds, more or less, according to the nature of the particular
substances under treatment. We prefer to heat the digester by means of a steam
jacket surrounding it, as in this way it can be applied evenly and with the best
results. The combined effect of the heat and acid is to rapidly destroy the fiber of
the hair or other substance and reduce it to a pulpy mass.
After the treatment above outlined, there is added to the mass a sufficient
quantity of alkaline matter such as lime, caustic soda, potash, phosphate rock or
bone, to take up or neutralize the free acid left in the mass.
The resulting
mixture is then dried and, if necessary, ground, and the result is a dry ammoniate
product which is a valuable fertilizer.
A second and preferred method of carrying out the invention is as follows:
Instead of using sulphuric or other acid in the liquid form, we mix the hair or
other nitrogenous material with dissolved bone or other acid phosphate, and add
a little water if necessary. We find that the dissolved bone or acid phosphate
contains sufficient free acid to effect the reduction of the nitrogenous material.
Before subjecting the mixture to heat, any additional elements which it is desired
to put into the fertilizer may be added, such for instance as an acid potash, soda
or magnesia.
The proportions of hair, etc., and acid phosphate or dissolved bone will depend
entirely upon the resultant fertilizer desired. Or, in other words, upon the
percentage of ammonia required in the fertilizer. We have found that three
parts of acid phosphate added to two parts of hair yields about 4.8 per cent. of
ammonia; also that three parts of acid phosphate combined with one part of bair
will produce about three per cent. of ammonia. This latter proportion is the usual
one in commercial fertilizers. When used in the above proportions or in any
proportions required for fertilizers, there is always sufficient free acid in the acid
phosphate to reduce the hair, etc.
After the hair or its equivalent has been mixed with the acid phosphate and
with any other substances which it is desired to incorporate with the fertilizer,
such as acid potash or soda, the mixture is placed in a steam-tight vessel and
subjected to heat until the fiber of the animal matter is entirely destroyed. The
operation is preferably performed in a vessel which is provided with a steam

page_text: contents.
jacket, by which means heat may be applied without the danger of scorching the
It is also preferable that the vessel be provided with a stirring device,
or be fitted to rotate upon an axis, in order that the contents may be thoroughly
mixed while the heating operation is taking place.
By the above process we are enabled to make a high grade fertilizer at a very
small cost, apart from the first cost of the raw materials. Furthermore, the
apparatus required is simple and comparatively inexpensive, and the time required
to complete the operation is very short, owing to the rapid action of the acid upon
the animal matter.
In the above Specification we have referred to sulphuric acid only. So far as the
invention is concerned, other acids, such as nitric and hydrochloric are the
equivalents of sulphuric, but as the latter is the cheapest and the only one likely to
be used, we have not referred to the others in the description.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In the manufacture of fertilizers, the improvement which consists in mixing
hair or equivalent nitrogenous material with a weak solution of acid, enclosing the
mixture in a steam-tight vessel, then applying sufficient heat to vaporize the water
of the acid solution and disintegrate the hair, and then adding sufficient alkaline
matter to neutralize the free acid, as set forth.
•
2. In the manufacture of fertilizers the improvement which consists in first
mixing together hair or equivalent material and an acid phosphate, and then
subjecting the mixture to heat in a closed vessel, until the hair or equivalent
material becomes disintegrated and dissolved, as set forth.
3. In the manufacture of fertilizers the improvement which consists in first
mixing together hair or equivalent material, an acid phosphate, and any other
desired ingredients such as an acid potash or soda, and then placing the mixture in
a closed vessel and subjecting it to heat until the hair or equivalent material
becomes disintegrated and dissolved, as set forth.
Dated this 6th day of February 1894.
W. P. THOMPSON & BOULT,
Agents for the Applicants.