Obtain Whiting and Cement and in Apparatus therefor.
Year: 1887

page_text: Date of Application, 18th Aug., 1887
-Complete Left, 4th Apr., 1888
Complete Accepted, 11th May, 1888
to Obtain Whiting and Cement and in Apparatus therefor.
I, JOHN SAMUEL RIGBY of Heathfield House Holywell, in the county of Flint,
Manufacturing Chemist do hereby declare the nature of this invention to be as
follows:-
The objects of the invention are to treat in a simple and effectual manner lime mud
obtained as waste material in the Leblanc alkali process or like waste carbonates of
lime contaminated with a small percentage of sulphur or hydrate of lime or both so
as to fit them for use as whiting and cement and to provide suitable apparatus for
carrying my invention into effect.
I first subject the lime mud or like substances or waste material to the action of
carbonic acid or to the action of a carbonate and wash and filter the said treated
material until practically pure carbonate of lime is obtained. When whiting is to be
produced I dry the washed and filtered material. I preferably agitate the material
during drying and afterwards grind. When cement is to be obtained the washed and
filtered material is mixed with clay or suitable aluminiferous material and burned in
the apparatus hereinafter described.
Apparatus under my invention for the manufacture of whiting consists in the
combination of a carbonating vessel, which may be the usual causticizer of alkali
works, with filter beds and drying appliances. In addition to these I employ a furnace
such as a rotary black ash furnace when cement is to be made.
Agitators are advantageously used for aiding the admixture of the clay and treated
lime mud or like material.
Dated this Seventeenth day of Anonst. 1887.

page_text: Improvements in the Treatment of Lime Mud and like Substances
to Obtain Whiting and Cement and in Apparatus therefor.
I JOHN SAMUEL RIGBY of Heathfield House Holywell in the county of Flint
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 :-
The objects of the invention, are to treat in a simple and effectual manner lime mud
or like impure carbonate of lime obtained as waste material in the Le Blanc alkali
process and, contaminated with a small percentage of sulphur or hydrate of lime, or
both, so as to fit it for use as whiting and cement and to provide suitable apparatus for
carrying my invention into effect.
I first subject the lime mud to the action of carbonic acid gas or a solution thereof
or to the action of a carbonate such as carbonate of soda or potassa in solution, until
the sulphur is eliminated and the hydrate of lime is carbonated. I then wash the
treated material with water in any convenient apparatus and filter the said washed
material in a filter bed or equivalent apparatus.
When whiting is to be produced I dry the said washed and filtered material on a
drying bed or in any suitable apparatus such as a tower with shelves for eliminating
moisture at a temperature say not exceeding 220° F. The material should be agitated
whilst being dryed and the drying may be effected by currents of heated air or gas
passed through or in contact with the material or by means of steam heat or the heat
of products of combustion transmitted through metallic surfaces or both systems of
drying may be employed. The treated material is then ground in a roller or other
suitable mill and is ready for market.
When cement is to be obtained the washed and filtered material is mixed with clay
or suitable aluminous substance and calcined.
Lime mud of average quality is carbonated by means of limekiln gas in about an
hour and by carbonate solutions in varying times according to the strength of the
solution. If the gas given off during the calcination of slurry into clinker is used the
time of treatment should be about an hour and a half.
Apparatus under my invention for the manufacture of whiting consists in the com-
bination of a carbonating vessel which may be the usual causticiser of alkali works,
with filter beds, and drying appliances. In addition to these I employ a furnace such
as a black ash furnace when cement is to be made.
Agitators are advantageously used for aiding the admixture of the clay and treated
lime mud or like material.

page_text: Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is.
First. In the manufacture of whiting carbonating lime mud washing and filtering
the carbonated mud and drying and grinding the same substantially as set forth.
Second. In the manufacture of cement carbonating lime mud, filtering and washing
the treated mud mixing the same with clay or suitable aluminous material and calcining
the mixture substantially as set forth.
Third. The combination of carbonators filters and drying apparatus for the manu-
facture of whiting substantially as set forth.
Fourth. The combination of carbonators filters and calcining furnaces for the
manufacture of cement.