AN IMPROVED MEANS OF PREVENTING INCRUSTATION IN STEAM BOILERS
Year: 1874

page_text: LETTERS PATENT to John Yeldham Betts, of Coventry, in the County
of Warwick, Miller, for the Invention of "AN IMPROVED MEANS OF
PREVENTING INCRUSTATION IN STEAM BOILERS."
Scaled the 19th January 1875, and dated the 13th August 1874.
PROVISIONAL SPECIFICATION left by the said John Yeldham Betts at
the Office of the Commissioners of Patents, with his Petition, on
the 13th August 1874.
I, JOHN YELDHAM BETTS, of Coventry, in the County of Warwick,
Miller, do hereby declare the nature of the said Invention for "AN
IMPROVED MEANS OF PREVENTING INCRUSTATION IN STEAM BOILERS," to be as
follows:-
:-
This Invention relates to the treatment of feed water before it is
supplied to the steam boiler, the object being to retain in solution the
earthy matters which the feed water may contain, or to prevent tho
formation of a hard calcareous deposit within the boiler. To attain this
end I first ascertain the proportion of earth carbonates existing in the

page_text: water intended to be used, and I then treat the water before it is pumped
into the boiler with hydrochloric acid in such proportions as will serve
to convert the carbonate into muriate of lime. Thus when the water
is heated and evaporation takes place, there will be (instead of the
insoluble carbonate which precipitates and forms a solid deposit) a
perfectly soluble salt which will remain in solution in the water of the
boiler and prevent the formation of "scale," or a stony precipitate in
the boiler. When sulphate as well as carbonate of lime is present in
the water the resulting muriate would mix with the sulphate and form a
soft precipitate easily removed from the boiler.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Yeldham Betts in the Great Seal Patent Office
on the 13th February 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
YELDHAM BETTS, of Coventry, in the County of Warwick, Miller, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent,, bearing date the Thirteenth day of August, in the year of our
Lord One thousand eight hundred and seventy-four, in the thirty-eighth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said John Yeldham Betts, Her special licence that I,
the said John Yeldham Betts my executors, administrators, and assigns,
or such others as I, the said John Yeldham Betts, my executors, admini-
strators, 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 "AN IMPROVED MEANS OF PREVENTING INCRUS-
TATION IN STEAM BOILERS," upon the condition (amongst others) that
I, the said John Yeldham Betts, 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 the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
ز

page_text: Patent.
NOW KNOW YE, that I, the said John Yeldham Betts, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement (that is to say) :—
::
Hitherto it has been the practice when using hard, water, or water
containing earthy impurities in solution to supply to the boiler from
time to time chemical substances that will act upon or combine with
the earthy impurities, and either maintain them in suspension or ensure
a deposit of a more or less granular character. I have found however
that by charging the boilers at given periods with the chemical sub-
stances suitable for effecting either of these results, not only is an excess
of the chemicals employed found necessary, but the efficiency of the
action set up cannot be maintained, as the tendency is for the action to
slacken as the chemicals become exhausted. To remedy this and ensure
a constant and efficient action I propose to treat the feed water chemically
before it is supplied to the steam boiler, and thereby to retain in solu-
tion the earthy matters which the water may contain, or to prevent
the formation of a hard calcarcous deposit within the boiler. To attain
this end I first ascertain by any well-known tests the proportion of
earthy carbonates existing in the water intended to be used, and I then
treat the water before it is pumped into the boiler with hydrochloric
acid, in such proportions as will serve to convert the earthy carbonate
into muriate of lime. Thus when the water is heated and evaporation
takes place, there will be (instead of the insoluble carbonate which pre-
cipitates and forms a solid deposit) a perfectly soluble salt which will
remain in solution in the water of the boiler and prevent the formation
of "scale," or a stony precipitate in the boiler. When sulphate as well
as carbonate of lime is present in the water, the muriate resulting from
the combination of the hydrochloric acid with the earthy carbonate will
mix with the sulphate and form a soft precipitate easily removed from
the boiler.
Having now set forth the nature of my Invention of "An Improved
Means of Preventing Incrustation in Steam Boilers," and explained the
manner of carrying the same into effect, I wish it to be understood that
I do not claim the application of hydrochloric acid to steam boilers for

page_text: preventing incrustation, as the use of that and equivalent materials for
such purpose is well known; but what I claim under the above in part
recited Letters Patent is, treating feed water previously to its intro-
duction into the boiler in the manner and for the purpose above
described.
In witness whereof, I, the said John Yeldham Betts, have here-
unto set my hand and seal, the Twelfth day of February, in
the year of our Lord One thousand eight hundred and seventy-
five.