IMPROVEMENTS IN TREATING CERTAIN SALTS AND GASES, OR VAPORS
Year: 1848

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FRANK
CLARKE HILLS, of Deptford, in the County of Kent, Manufacturing Chemist,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Nineteenth day of
October, One thousand eight hundred and forty-eight, in the twelfth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Frank Clarke Hills, my exors, adñiors, and assigns, Her especial.
licence, full power, sole privilege and authority, that I, the said Frank Clarke
Hills, my exors, adñiors, and assigns, or such others as I, the said Frank Clarke
Hills, my exors, adññiors, or assigns, should at any time agree with, and no-
others, from time to time and at all times during the term of years therein
expressed, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, my Invention of
"IMPROVEMENTS IN TREATING CERTAIN SALTS AND GASES, OR VAPORS;" in which
said Letters Patent is contained a proviso that I, the said Frank Clarke Hills,
should cause a particular description of the nature of my said Invention, and
in what manner the same is to be performed, by an instrument in writing
under my hand and seal, to be inrolled in Her Majesty's High Court of

page_text: Chancery within six calendar months next and immediately after the date
of said in part recited Letters Patent, as in and by the same, reference being
thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I have
ascertained and set forth the nature of my Invention, and the manner of
carrying the same into effect in and by the following description thereof:-
My Invention consists, firstly, of certain processes for improving the illumi-
nating power of coal gas, and for obtaining a larger quantity of it from a given
quantity of coals. One of my processes to effect this is as follows:-The tar,
which is produced in the ordinary way of making gas from coals is to be deprived
of its naptha by distillation, and the thick tar or pitch which remains is to be
mixed, whilst hot, with sufficient breeze from the ordinary gas coke to render it
solid and hard when cold. This composition may be distilled in retorts by itself
like ordinary coals, but I prefer to mix it with the coals to be used for making
gas, or a certain quantity of it may be thrown into the retorts, on the top of the
charge of coals. What are termed "reciprocating retorts," in which the gas
from one retort passes through the other, in which the coke is red hot, are
best adapted for this method. By this means a larger quantity of gas will be
obtained, and of better quality than by the ordinary method; also the breeze
will be converted into good coke, which is more valuable than breeze.
Instead of mixing the thick tar or pitch with the breeze it may be mixed in
the same manner with the coals to be distilled; but, in this case, it would be
best to continue the distillation of the tar for a longer period than when breeze
is used.
Another method of increasing the illuminating power of gas is to cause
the thick tar or pitch, deprived of its naptha, as before described, to run while
hot in a gentle stream into retorts (preferably set vertically) kept at a red heat,
and partially filled with coke. The tar will run upon the heated surface of
the coke in the retort, forming more coke and generating gas, which should
descend through the heated coke in the retort, and escape at the lower end;
when the retort becomes about two thirds full of coke the coke must be
removed. The naptha vapor produced from the tar by distillation may be
either condensed into naphtha, by passing it through a refrigerator, or it may
be converted into gas by passing it through retorts (preferably set vertically)
kept at a red heat, and filled with coke, brick bats, or other suitable material,
as described for the thick tar.
Another method of treating illuminating gases is to mix waste gas from
the distillation of wood in the process of forming pyroligneous acid (and

page_text: which is well understood) with the rich carburretted hydrogen gas obtained
from the decomposition of tar or pitch or other hydro-carbons, or from cannel
or other coals.
I claim under this head of my Invention,―
First, the mixing pitch, or coal tar deprived of its naptha, with breeze,
small coke, or coals, to be used in conjunction with ordinary coals to
make gas.
Secondly, running thick tar or pitch into retorts kept red hot, and preferrably
partly filled with coke or other substance to make heated surface, and over
which surface the generated gas is to pass.
Thirdly, passing the vapor of naphtha obtained from the distillation of the
tar through red-hot retorts preferably containing coke, so as to form a highly
illuminating gas.
Fourthly, the mixing the waste gas from wood (in the process of making
pyroligneous acid) with gas obtained from the rich hydro-carbons or from
coals.
My Invention consists, secondly, in a method of distilling the volatile solu-
tions of ammonia, so as to obtain the ammonia in a more concentrated form;
and also for concentrating saline solutions and sulphuric acid. To effect the first
of these objects, I make a chamber or tower preferably circular, and the height
of which should be about ten times its diameter. This tower should have a
series of trays or gratings of iron, or wickerwork to fit the interior of the
tower, and placed one above another, about two feet apart, from the bottom to
the top of it. The spaces between these gratings are to be nearly filled with
small coke or breeze, clinkers, broken tiles, or eathenware, or such like
materials, so as to present a large surface for the liquor to be distilled to run
over. The trays are for the purpose of supporting the media, but the tower
may be simply filled without the trays, if preferred. The ammoniacal liquor to
be distilled is run into the tower at the top, in such a manner as to be distributed
all over the surface as equally as possible, whence it percolates through the
greatly divided media in the tower. Steam or hot air is at the same time
admitted into the tower at the bottom, and forced or drawn upwards through
the divided media to meet the descending liquid. The ammonia will be
vaporized by the heat, and will escape at the top of the tower, from whence
it may be taken and condensed in any convenient way, and the waste liquid,
deprived of its ammonia, will run off at the bottom of the tower. Another
tower, a few. feet high, like the one just described, and preferably filled
with the same materials, and which I call a "concentrator," may be connected
on to the top of the first tower, and a pipe may be coiled round the interior of

page_text: it from top to bottom, or may be supported on the media used, and the
animoniacal vapors are caused to pass through this tower on their way from
the first tower to the condenser. The liquor to be distilled is to be run
through this pipe, and will be warmed in its descent through it by the ascending
ammoniacal vapor from the still, and at the same time the cold liquor running
through the pipe will condense the watery or less volatile portion of the
ammoniacal vapor, and the remainder will then pass to the condenser.in a more
concentrated state. To concentrate the saline solutions, which are not
volatile at moderate heats, I employ the same tower as first described. The
solution is to be run in at the top of the tower, and to percolate through the
media contained in it, which, as well as the supporting trays, in this case
must not be combustible. Air heated to the requisite point, by passing
through red hot tubes or otherwise, or the gaseous products of combustion,
if free from smoke, are to be admitted at bottom, and may be drawn through
the tower by the draft of a chimney or by mechanical means, and meeting the
descending liquor, will evaporate or drive off the water, and a more concen-
trated solution will run off at bottom. The aqueous vapors may be driven off
from sulphuric acid in the same way, only that in this case the tower must
be lined with earthenware, or other material to stand the action of the acid;
and the media employed for the acid to percolate through must be broken
glass, earthenware, or pebbles, or other substance that will not affect the acid.
Weak sulphuric acid will be distilled off by the heated air, &c., and the con-
centrated acid will run out at the bottom of the tower.
I claim,―
First, under this head of my Invention, distilling the volatile solutions
of ammonia, whether pure or mixed with other matters, by running them
through greatly divided media in any convenient chamber or ctill, and
admitting steam or heated air in an opposite direction to come into direct
contact with the solutions, so as to vaporize and drive off the more volatile
parts.
Second, the concentrating saline solutions, as described, by causing them
to percolate through media contained in a tower or chamber, as herein-before
described, whilst a current of heated air, or of the gaseous products of
combustion, is caused to pass through or over the same media in an' opposite
direction.
Thirdly, the driving off the more aqueous vapors of sulphuric acid, by
passing heated air or the gaseous products of combustion through a tower
containing suitable media, as before described; through which media the
sulphuric acid percolates.

page_text: My Invention consists, further, of a method of impregnating liquids with
gases or vapors that are soluble in them, or for which they have an affinity,
but it is chiefly intended for absorbing ammoniacal vapors, whether pure or
mixed with other gases, into water, saline ammoniacal solutions, or liquid
acids. To effect this, when water, weak ammoniacal solutions, or weak acids
are used, I employ a chamber or column, such as I have described for dis-
tilling ammoniacal solutions, &c.; but instead of using the media there
described, I employ sawdust, tan, cocoa-nut fibre, or pumice stone, broken
small. These materials are to be placed in the trays or gratings in the tower,
instead of coke, &c., and the openings in the gratings must be small enough
to prevent the sawdust, &c. falling through. The liquid for absorbing the
vapors is to run into the tower at the top in any required quantity, and is to
percolate through the sawdust, &c. so as to keep it uniformly damp or wet.
The vapors to be absorbed into the liquid, are to be admitted into the bottom
of the of the tower, and in making their way upward through the wet media,
and coming in contact with its large wet surface, they will be absorbed by the
liquid, which will gradually fall to the bottom of the tower, and will thence run
out. If fixed saline ammoniacal solutions are employed instead of water, &c.,
coke or breeze, or such like media, may be used instead of sawdust. Instead
of using an upright chamber or tower, another method of absorbing vapors
or gases into liquids is to pass them through a horizontal cylinder, in the
centre of which an axis or spindle is placed passing through the ends or covers
of the cylinder, and to which spindle brushwood or furze or matting or such
like substance is attached so as to touch the sides of the cylinder. The cylinder
is to filled about one quarter of its diameter with water, and the spindle is to
be caused to revolve, which will carry the brushwood, &c. round with it, the
extremities of which passing through the water will carry some of it up with
it, and which dropping from one point to another will make the whole wet,
and the vapor or gas passing through and coming in contact with the wet
surface will be absorbed into the liquid, which, when sufficiently saturated, is
to be run out, and fresh liquid to be introduced.
Another method of absorbing ammoniacal vapors is to soak breeze or coke,
or other suitable absorbent material, with liquid acid (preferably sulphuric
acid), and after drying the breeze, &c., to place it in vessels constructed like
dry lime purifiers, employed at gasworks, and then causing the ammoniacal
vapors, whether pure or mixed with other gases, to pass through the
breeze, &c. In their passing the vapors will unite with the acid, and form
sulphate (or other salt of ammonia, according to the acid which may be
employed).

page_text: I claim under this head of my Invention the effecting the absorption of
vapors by liquids for which they have affinity by the methods herein-before
described.
My Invention consists, further, of the following methods of extracting or
clearing noxious or offensive gases from vessels in which ammoniacal waters
are saturated, or from the purifiers of gasworks, in which lime or other puri-
fying material is used, so as to make both the purifiers and also the materials
employed in purification much sweeter, so that the materials may be removed
from the purifyer without annoyance to the workman and without making a
nuisance. To accomplish these objects I cause a current of steam or atmo-
spheric air, either heated or at common temperatures, or the gaseous products of
combustion, or any other suitable gas, to be drawn or forced through the
purifyer, &c., and also through the purifying materials, either by the draught of a
chimney or by an exhausting machine. The purifyer must be connected to the
chimney, &c. by suitable pipes for the gases to pass through, and it is preferable
that the air, &c. should be drawn downwards through the purifyer by fixing
the exhausting pipe at the bottom of the purifyer, &c. The current of air
will carry away along with it the noxious or other vapors with which the
purifying materials are impregnated. By using highly-heated air or the
gaseous products of combustion, certain sorts of purifying material, such as
dry lime, &c. may be so far renovated as to be fit to a certain extent of being
worked over again as a purifying material. Should it be desired to retain any
of the gases which exist in the purifier or purifying materials, the pipe which
conveys the gases away from the purifiers, &c. should be connected to one
end of an absorbing vessel, such as herein before described, and from the oppo-
site end of the same vessel a pipe should lead to the exhausting machine, so as
to cause the gas to pass through the medium contained in the absorbing vessel,
as before described, whereby it will be retained. If the gases are condensable,
a common condenser, consisting of a series of pipes preferably surrounded by
water, may be substituted for the absorbing vessel above mentioned. To pre-
vent the gas extracted from forming explosive compounds, I admit a current of.
stean or of atmospheric air, carbonic acid gas, or other suitable gas, into the
pipe which conveys the gases to the chimney. If steam be employed it should
be in the proportion of one third of the bulk of the gas extracted, but if air or
other gases be used they should be in the proportion of at least sixteen times
the bulk or quantity of the gas extracted, which will render them inexplosive.
The admission of the steam and air may be regulated in any convenient way.
I claim,
First, under this head of my Invention, extracting or clearing noxious or

page_text: other vapours from ammoniacal saturators, gas purifiers, and absorbing vessels,
and from the materials used in them, by causing a stream of steam, atmospheric
air, or other suitable gas or vapors, whether heated or at common temperatures,
to pass through them, and thence to a furnace or chimney.
Secondly, preventing the formation of explosive mixtures from gases drawn
from the vessels and materials above described, by mixing a sufficient quantity
of steam or of atmospheric air, carbonic acid, or other suitable gases, as to
render them inexplosive.
My Invention further consists in methods for introducing the liquids either
into the stills or the absorbing vessels, so as to distribute them equally over the
surface. One method which I employ is as follows:-I place a series of pipes.
at the top of the vessels, equally divided over the whole surface, about eighteen
inches apart. On the opposite sides of these pipes, at regular intervals apart,
I drill small holes about one-sixteenth of an inch in diameter. The liquid is.
to be admitted into these pipes at intervals from a tumbler placed at a higher
level in sufficient quantity to spread in little jets all over the surface. The
tumbler is for changing a continuous stream of liquid from a regulating cock
into an intermittent supply, so as to accumulate a sufficient quantity to spread
all over the surface at each admission of it into the series of pipes. The
tumbler is a vessel divided into two triangular or hopper-shaped compart-.
ments by a central plate standing at right angles to the bottom plate of the
tumbler, and extending from side to side. The tumbler is placed in a box,
and is free to vibrate upon two pivots attached to the under side of it in a line
with the division plate. These pivots turn in bearings situated a few inches
above the bottom of the box. Immediately over the centre of the tumbler is a
supply cock connected with the vessels containing the liquid, and a pipe pro-
ceeds from the bottom of the box to the distributing pipes in the absorbing or
distilling vessels. If one end of the tumbler be depressed the position of the
centre of gravity will become changed, and that end of the tumbler will rest
upon the bottom of the box, and the compartment at the opposite end will be
brought under the supply cock; but after a certain quantity of liquid has
flowed from the cock into the upper compartment it will acquire a prepon-
derance, and will suddenly descend to the bottom of the box, discharging the
liquid into it (whence it will run into the distributing pipes), and raising the
opposite compartment, which, being charged, descends in like manner, and so
on, alternately filling each side of the tumbler with the requisite supply of
liquid to give a sufficient jet of water in the series of pipes to spread over the
surface, and to keep it sufficiently damp or wet.
Another method of regulating and spreading the liquids over the surface of

page_text: the stills or absorbing vessels, when they are of a circular form, is to place an
upright hollow spindle closed at bottom in the centre of them, with one or
more pipes radiating from it and extending to the sides of the vessel, so that
when liquid is poured into the hollow spindle it will run into the pipes or
arms. These are to have small holes drilled in them at the bottom at regular
intervals, for allowing the liquid to escape, and the spindle being made to
rotate by any suitable means the liquid will be equally distributed over the
area of the vessel.
I claim under this head of my Invention the distributing the liquid equally
in the stills or in the absorbing vessels by means of a tumbler or by revolving
perforated arms, as herein-before described.
My Invention consists, lastly, in a method for depriving coal gas of its
naphthaline. This I effect by passing the gas (after it has been purified and
before it enters the gasometer) through a vessel similar to a wet lime purifier,
in which is placed a solution of caustic potash and lime, or caustic soda and
lime. The naphthaline will be retained to a considerable extent by the alkalies.
And―
I claim accordingly the freeing coal gas from its naphthaline by causing it
to pass through a solution of caustic potash and lime or caustic soda and
lime.
In witness whereof, I, the said Frank Clarke Hills, have hereunto set my
hand and seal, this Seventeenth day of April, in the year of our Lord
One thousand eight hundred and forty-nine.