IMPROVEMENTS IN REBURNING ANIMAL CHARCOAL
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by the said James Robey at the
Office of the Commissioners of Patents, with his Petition, on the 3rd
April 1866.
I, JAMES ROBEY, of Newcastle-under-Lyme, in the County of Stafford,
Sugar Refiner. do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN REBURNING ANIMAL CHARCOAL," to be as follows:-
This Invention has for its object improvements in reburning animal
charcoal, and consists in combining or mixing salammoniac with animal
charcoal when the same requires to be reburned, and then reburning
these combined or mixed substances. It should be stated that it has
before been proposed to mix salammoniac with animal charcoal in order to
render the lime therein soluble, to which mixing separately I make no
claim.
In carrying out my Invention I prefer to employ the salammoniac in the
state of dry powder, as it is not desirable to increase the quantity of water
[Price 6id.]

page_text: already present in the animal charcoal as it comes from the filters, but a
saturated solution of salammoniac might be employed; this, however, would
increase the quantity of fuel necessary for driving off the water before the
effect of the usual heat employed in reburning can act on the salammoniac
present and cause it to be converted into vapour. By thus treating the
mixture of animal charcoal and salammoniac it is found that the lime and the
hydrochloric acid combine, whilst the ammonia is driven off and may be
collected and again' used in the manufacture of salammoniac. With this object
in view prefer to employ upright or revolving retorts, such as are now used in
reburning animal charcoal, though other forms of apparatus may be employed
in place thereof. The quantity of salammoniae used in each case depends
upon the quantity of lime present, and it is found that seldom more than
five per cent. by weight of salammoniac is required, and generally much less.
The animal charcoal after reburning and before being returned into the filters
is washed with water.
SPECIFICATION in pursuance of the conditions of the Letiers Patent. filed
by the said James Robey in the Great Seal Patent Office on the 2nd
October 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
ROBEY, of Newcastle-under-Lyme, in the County of Stafford. Sugar Refiner,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria. by Her Letters
Patent, bearing date the Third day of April. in the year of our Lord One
thousand eight hundred and sixty-six, in the twenty-ninth year of Her reign.
did, for Herself. Her heirs and successors, give and grant unto me, the
said James Robey. Her special licence that 1. the said James Robey, my
executors, administrators, and assigns, or such others as I, the said James
Robey, my executors, administrators, and assigns. should at any time agree
with, and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise.
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN RE.
BURNING ANIMAL CHARCOAL," upon the condition (amongst others) that I, the
said James Robey, my executors or administrators. by an instrument in
writing under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what manner

page_text: the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said James Robey, do hereby declare the
nature of the said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
thereof, that is to say:-
This Invention has for its object improvements in reburning animal
charcoal, and consists in combining or mixing salammoniac with animal
charcoal when the same requires to be reburned, and then reburning
these combined or mixed substances. It should be stated that it has
before been proposed to treat animal charcoal with salammoniac in order to
render the lime therein soluble, to which mixing separately I make no
claim.
In carrying out my Invention I prefer employing either the crude
salammoniac of the manufacturers in the state of powder, or of small
crystals, or the equally crude liquid salammoniac obtained from muriatic
acid and gas water, principally on account of the strengthening effect of the
carbon they contain, and also by reason of the cheapness of these forms of
that article. By reburning the mixture of animal charcoal and salammoniac
it is found that the lime, as well as some other objectionable matters, combine
with the muriatic acid of the salaminoniac, and are rendered soluble, whilst
the ammonia is driven off and may be collected again. With this object in
view prefer to employ upright pipes or retorts heated externally, such as
are now used in reburning animal charcoal. The quantity of salammoniac
to be used will depend upon the amount of lime present, but I have found
that three or four per cent., if in the state of small crystals or powder, or in a
like relation if in solution, is sufficient to use the first time with charcoal
which has been a long time in use. After the charcoal is once quite restored
by this process but very little is subsequently required. The animal charcoal
after reburning is to be well washed with water to remove all soluble
impurities, and although I have found that it may be used directly after
washing prefer to reburn again before using. I intimately mix with the
animal charcoal, before it is reburned, the salammoniac, whether in the
state of powder or small crystals or in the liquid state. The animal charcoal
is then to be reburned as above stated.
The form of apparatus and the means of applying heat to the animal
charcoal for driving off the ammonia may be varied, and I have found that
superheated steam passed freely through the mixture of animal charcoal and

page_text: salammoniac may be employed in place of externally heating the retorts by
fire. I, however, believe that the process of reburning is most conveniently
and advantageously carried on in ordinary upright retorts heated externally by
fire.
When it is desired to recover the ammonia driven off by heat from the
animal charcoal mixed with salammoniac I use a close head or cover, and
thereby collect and carry off the ammonia, as is well understood in other
processes.
I would here state that neither the means of applying the requisite heat to
animal charcoal for driving off the ammonia nor the collection of the ammonia
driven off are claimed by me; but what I do claim is the combined use of
salammoniac with the application of heat, and subsequent washing of the
reburned animal charcoal with water, as herein described.
In witness whereof, 1, the said James Robey, have hereunto set my
hand and seal, this Twenty-fourth day of September, in the year of our
Lord One thousand eight hundred and sixty-six.