containing Calcium-chloride.
Year: 1885

page_text: containing Calcium-chloride.
I, JAMES WEBSTER, of Fern House Solihull Lodge, Holly Wood, near Birmingham,
in the County of Warwick, Engineer, 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:-
My invention relates to a new method of treating the waste liquors from such
branches of chemical industry as the manufacture of chlorine gas, and various
single and double chlorides and carbonates. As one of the numerous industries
which yield a waste liquor suitable for the purposes of my invention, I may mention
the manufacture of carbonate of ammonium from chloride of ammonium.
The respective waste liquors referred to have all this in common, viz., they all
hold chloride of calcium, or calcium-chloride as it is commonly called at the present
day, in solution.
It has hitherto been the practice to regard this calcium chloride liquor as worse
than a waste or useless substance, and as exceedingly offensive.
In carrying out my invention, I run a quantity of the above mentioned liquor
into a vat, or tank, of suitable proportions, and conveniently situated for the
purpose of my invention.
As much slaked lime, or calcic carbonate in any well-known condition, is next
thrown into the vat, as will absorb the liquor therein, and the whole is well stirred.
The mass becomes of the consistence of mortar, so that it can be conveniently
handled by shovelling.
It is taken out of the vat and introduced into a drying furnace of any well-
known and suitable construction, the temperature of which is raised gradually to
about 250° F., but not higher, the whole mass being raked about so that every
particle shall be subjected to the heat equally throughout and all the water
moisture expelled therefrom, without its chemical composition being affected.
The vat is filled a second time with the liquor, and the dried mass taken out of
the furnace and thrown therein. It is well-worked as before, and when it has
taken up as much liquor as it is capable of doing, it is a second time removed
to the drying furnace, and subjected to a second drying conducted in the same
way, for the same purpose, and within the same limit of temperature, as before
described.

page_text: As the mass dries this second time, a large number of hard lumps will appear,
the production of which I consider to be due to the absorption of calcium chloride,
or chlorine free or combined, from the liquor.
The presence of these hard lumps makes it necessary to grind the mass, to
facilitate the further absorption of liquor, after which it is thrown into the vat a
third time, a suitable quantity of fresh liquor having, in the meantime, been run
into the vat.
The whole mass is again well-stirred, and when it has become of about the
consistence of mortar it is taken to the drying furnace and dried again as before.
I find that the dried mass is, as a rule, now incapable of absorbing any more of
the chlorine compounds from the liquor, if the above processes have been carefully
performed, but I do not confine myself to three immersions of the lime in the
liquor, followed by three dryings, inasmuch as the number can be varied, if
. required or desirable, provided that the lime be allowed to take up and retain as
much of the chloride compounds of the liquor as it is capable of doing, this
absorption by the lime being an essential feature of my invention, and, consequently,
necessary to its successful operation.
The resultant substance is next melted, and cast into blocks, for convenience in
dealing with it in any application for which it is adapted.
I do not confine myself to any particular arrangement of plant, as the size and
relative numbers of vats and drying furnaces are decided according to convenience,
or the special requirements of each particular installation.
I find that the substance resulting from the above described method of utilising
calcium chloride waste liquor, may be advantageously used as a flux in metal-
lurgical operations, such as the refining of copper, brass, nickel, zinc, tin, aluminium,
or other metals or alloys.
When it is proposed to use it as a flux in the refinement of iron, I add from 15
to 20% of peroxide of manganese, the percentage varying according to the
natural degree of purity of the iron to be refined.
If it is to be used as a flux in a puddling furnace, I add 20% of peroxide of
manganese, calculating the percentages above mentioned upon the weight of the
flux.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The process for utilising waste liquors containing calcium chloride, by
alternately mixing them with lime, (slaked, or in any other familiar condition),
and then drying the mass, until it is fully charged with the calcium chloride;
substantially as and for the purpose herein before described.
2. The combination of the dried mass resulting from the process defined in the
first claim, with peroxide of manganese, for use as a flux in the refinement of
iron; substantially as above described.