Improvements in the Manufacture of Cement and the Utilisation of the Lime-mud Residue of the Ammonia Soda Process therefor.
Year: 1888

page_text: Date of Application, 1st Mar., 1888
Complete Specification Left, 28th Nov., 1888
Complete Specification Accepted, 16th Feb., 1889
Improvements in the Manufacture of Cement and the Utilisation of
the Lime-mud Residue of the Ammonia Soda Process therefor.
I, JOHN SAMUEL RIGBY of 55 Bagot Street, Liverpool, in the County of Lancaster,
Manufacturing Chemist do hereby declare the nature of this invention to be as
follows:-
"
In my application No. 10244 of 1887 I described my invention for making cement.
out of lime mud as it is thrown out from the causticisers in the manufacture of
caustic alkali in Le blanc soda works. Finding that a somewhat similar material is
also a waste product of Ammonia Soda works I experimented with that also with a
view to its utilisation in a similar manner. I found however that it required a very
different treatment as the cement made from it would not harden and was quite
useless. I have however solved the problem in the following manner.
Finding that the lime mud contained large quantities of alkaline earth chlorides
which though very soluble & deliquescent are very difficult to wash out and which if
left in spoiled the product made from the lime mud I washed out as much as could
be got out with a reasonable amount of washing in hot or cold water and then added
an alkaline silicate preferably silicate of soda, sufficient-by double decomposition to
convert all the alkaline earth chlorides into insoluble alkaline earth silicates and an
alkaline (sodium) chloride. I then mix with finely divided aluminous matter (clay) in
the required proportion to make cement-calcine grind and purge in the usual
manner.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Agents for the Applicant.

page_text: the Lime-mud Residue of the Ammonia Soda Process therefor.
I, JOHN SAMUEL RIGBY of 35, Bagot Street, Liverpool in the County of Lancaster,
Manufacturing Chemist, 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:-
In my application No. 10244 of 1887, I described my invention for making cement
out of "lime mud "as it is thrown out from the causticisers in the manufacture of
caustic alkali in Le Blanc soda works. Finding that a somewhat similar material is
also a waste product of ammonia soda works, I experimented with that also, with a
view to its utilisation in a similar manner. I found, however, that it required a very
different treatment, as the cement made from it would not harden and was quite
useless. I have, however, solved the problem in the following manner :-
I prefer to first treat the lime mud while still in the semi-fluid state as received
from the decomposer, with carbonic acid under pressure or otherwise, and then wash
in a filter press, filter bed, or other suitable appliance, by which means I extract nearly
all the soluble salts. The lime mud still contains earth chlorides, which though very
soluble and deliquescent are very difficult to wash out, and which, if left in, spoil the
product made from the lime mud. J, therefore, after still further washing in hot or
cold water to get out as much of the alkaline earth chlorides as it will pay to do in
this way, add an alkaline earth silicate, preferably silicate of soda, sufficient, by double
decomposition, to convert all the alkaline earth chlorides into insoluble alkaline earth
silicates, and an alkaline chloride, which may be washed out if required. I then mix
with finely divided aluminous matter (clay), in the required proportion to make
cement (usually about 4 of lime mud to one of clay in the wet state), calcine, grind,
and purge in the usual manner.
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: --
Ist. The manufacture of hydraulic cement from the lime mud of ammonia soda
works, by washing the same, carbonating, adding alkaline silicate, mixing with finely
divided aluminous material in the requisite proportions, and then calcining, grinding,
and purging.
2nd. In the utilization of the Ammonia soda lime mud for cement making—
carbonating the same-whereby the various soluble salts can be extracted from it by
washing substantially as described.
T: 02nd d... of Navamban 1000