IMPROVEMENTS IN THE MANUFACTURE OF MANURE
Year: 1870

page_text: LETTERS PATENT to Campbell Morfit, Consulting Chemist, of the
City of Baltimore, in the State of Maryland, and United States of
America, but now residing at Sudbrook Park, in the County of
f
TAKT Tar
MANURACTURE OF
COMPLETE SPECIFICATION filed by the said Campbell Morfit at the
Office of the Commissioners of Patents, with his Petition and
Declaration, on the 7th September 1870, pursuant to the 9th
Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CAMPBELL
MORFIT, Consulting Chemist, of the City of Baltimore, in the State of
Maryland, and United States of America, but now residing at Sudbrook
Park, in the County of Surrey, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS
IN THE MANUFACTURE OF MANURE," and have petitioned Her Majesty to
grant unto me, my executors, administrators, and assigns, Her Royal

page_text: Letters Patent for the same, and have made solemn Declaration, that
I am the first and true Inventor thereof.
NOW KNOW YE, that I, the said Campbell Morfit, do hereby declare
that the following Complete Specification, under my hand and seal,
fully describes and ascertains the nature of the said Invention, and in
what manner the same is to be performed, in and by the following
statement thereof, that is to say -
My Invention consists in the use of sulphate of ammonia, sulphate of
potassa, the crude ammoniacal liquor of the gas or bone black works,
and commercial-carbonate-of-potassa for-recovering the hydrochloric
acid employed in making solutions of mineral or other crude phosphates
of lime, and producing at the same time a concentrated fertilizer.
To carry out the Invention practically the powdered mineral or rock
phosphate is to be added slowly but in regular current to commercial
hydrochloric acid, during constant agitation until the mixture is
complete. The containing vat must have a man-hole at the bottom for
the removal of the settled insoluble or waste matters, and cock or plug
tubes up the front at short intervals apart for drawing off the solution
when it is finished. The requisite quantity of commercial hydrochloric
acid having been poured into the vat is then to receive the powdered
mineral which is to be lifted from the ground by an elevator and dropped
into the vat from an endless belt by cupfuls at a time and during
constant agitation. The quantity of acid required will depend upon its
strength, and the greater or lesser proportion of carbonate and phosphate
of lime, oxides and phosphates of aluminium and iron which the crude
mineral may contain, and must be determined by a preliminary test
experiment, upon one hundred grains of the powdered mineral. As
much as two tons of commercial hydrochloric acid of specific gravity,
1.170 are required for the solution of one ton of certain mineral phos-
phates, but for South Carolina phosphate, "Sombrero" and "Navaza
guano," one and a quarter to one and a half tons would be sufficient.
The Spanish or Estramadura phosphorite needs even less or about an
equal weight of hydrochloric acid of specific gravity 1.170. When the
mixture is complete the vat is to be left undisturbed for three or four
hours, when its contents are to be again agitated. This alternate
repose and agitation is to be repeated at intervals of three or four
hours until the whole of the soluble matter of the mineral has been
taken up by the acid, and as may be known by examining-a sample

page_text: of the contents to be drawn out through a try cock, at this stage water
is to be added to dilute the mass, one half its volume, and it is then to
be well stirred and left to repose. In about two hours it will have
settled, that is the insoluble matters consisting of sand, silicates, and
more or less of aluminium and iron oxides, and phosphates will have
subsided, leaving a clear liquor above, holding in solution the lime
which exists in the mineral as phosphate and carbonate together with
a variable proportion of aluminium and iron oxides and phosphates
according to the temperature of the atmosphere surrounding the vat
at the time of digestion or solution. This clear liquor is to be drawn
off into a suitable open vat of wood or stone, after which the subsident
impurities are to be treated with two consecutive relays of fresh water,
and these wash waters drawn off like the first liquor and mixed with it.
The insoluble matters are then to be removed from the vat through the
man-hole and thrown aside. as waste. The liquor drawn off into the
vat is now to be treated with milk of lime, which latter must be thin,
smooth, and free from grit, and added only in the slightest excess to
prevent the debasement of the precipitated phosphate with carbonate
of lime. The lime used for making the milk must be in the fresh
caustic state of quicklime, and the proportion of five and a half to six
hundredweight per ton of hydrochloric acid of specific gravity 1-170
which may have been consumed in making the solution of the crude
mineral phosphate of lime, exclusive however of that portion consumed.
in neutralizing the carbonate of lime naturally present in the mineral.
Every pound of this carbonate of lime has become already one and one-
tenth of a pound of chloride of calcium by the action of two pounds of
the hydrochloric acid (specific gravity, 1·170) upon it. As soon as a piece
of red litmus paper when dipped into the liquor becomes blue the
addition of lime milk must be stopped. By this action phosphate of
lime together with the aluminium and iron oxides and phosphates are
precipitated by the lime, which unites in its turn with the hydrochloric
acid that held them in solution and becomes chloride of calcium, forming
the clear liquor above the precipitate, if the latter should be left to
settle. This solution of chloride of calcium contains also as chloride,
the carbonate of lime of the raw material or mineral, this salt not being
precipitated from its solutions in hydrochloric acid by milk of caustic
lime. The mixed mass is now to be heated by means of a current of
steam, and treated with a sufficient quantity of sulphate of ammonia
or potassa in powder or aqueous solution, either singly or together,.to

page_text: change its chloride of calcium into sulphate of lime and thus destroy
its property of humidity, which otherwise it would retain, however hard
it may be dried subsequently by heat. This chemical interchange of
bases introduces at the same time chloride of ammonium, or chloride of
potassium into the precipitated phosphate of lime, thus perfecting it as
a fertilizer, and securing the economy of its production by getting back
the acid used as solvent of the crude mineral in the profitable form of
ammonia or potassa salt. Without this treatment there would be no
commercial advantage in the process, and the product would be always
absorbing moisture and becoming damp. The quantity of ammonia_or
potassa sulphate, singly or together, which may be required to decompose
all the chloride of calcium liquor must be determined by testing a given
small portion of the latter in advance. If the sulphate of ammonia
should be employed alone, there must be added about seven-tenths of a
pound of that salt for every pound of hydrochloric acid of specific
gravity 1170 in the solution of mineral phosphate. On the other hand
when sulphate of potassa may be employed alone, then its proportion
should be about nine-tenths of a pound to every pound of hydro-
chloric acid (1·170) in the solution of mineral phosphate. The
resulting dry powder will consist of precipitated (Columbian) phosphate
of lime, sulphate of lime and ammonium, or potassium chloride
according as an ammonia or potassa sulphate may have been used in
its chemical preparation. To give completeness to the product as a
concentrated and potential fertilizer, both sulphate of ammonia, and
sulphate of potassa are to be used, the former in the proportion of six
and a half tenths, and the latter in the proportion of eight and a half
tenths of a pound to every pound of hydrochloric acid of specific gravity
1.170 in the solution of mineral phosphate. The salts are to be added
separately but consecutively in manner as already explained. This will
import ammonia and potassa salts into the fertilizer and the proportion
may be varied as required. During the addition of the salt or salts either
in powder or aqueous solution the mass must be steamed and raked so
as to insure a perfect solution and distribution throughout. This done,
it is then ready to be run upon the floor of a drying kiln and to be
dashed, when dry, into powder by means of a Howel mill, or Carr
disintegrator. The crude ammoniacal liquor of coal gas and bone
black works may replace very well the sulphate of ammonia, and so
also commercial carbonate of potassa may be substituted for the sulphate
of potassa; and as prescribed, with little or no difference in the manipu-

page_text: lations, and only this difference in the products, that carbonate instead
of sulphate of lime is formed.
Having thus described the nature of my said Invention and the mode
in which I carry the same into effect, I would have it understood that
what I claim, is the recovery of the hydrochloric acid employed in
making solutions of mineral phosphates of lime so as to produce
chlorides of ammonium and potassium separately, or associated with
non-humid precipitated phosphates of lime to form a very concentrated
manure, which I name Columbian Fertilizer, and by the means and after
the manner herein-before substantially set forth.
In witness whereof, I, the said Campbell Morfit, have hereunto
set my hand and seal, this Sixth day of September, in the year
of our Lord One thousand eight hundred and seventy.
CAMPBELL MORFIT. (L.S.)