A New or Improved Apparatus for Estimating the Carbonic Acid or other Constituents in Gases or Products of Combustion.
Year: 1895

page_text: Date of Application, 22nd Nov., 1895
Complete Specification Left, 22nd Aug., 1896-Accepted, 21st Nov., 1896
PROVISIONAL SPECIFICATION.
A New or Improved Apparatus for Estimating the Carbonic Acid or
other Constituents in Gases or Products of Combustion.
I, GEORGE CRAIG of Lugar Iron Works, Cumnock, in the County of Ayr,
North Britain, Chemist, do hereby declare the nature of this invention to be as
follows:-
This invention relates to a new or improved process and apparatus for ascertaining
the amount of carbonic acid or other constituents in gases or products of combustion
from coal or other material.
The process consists in passing a given quantity of the said gases or products
through or over a material which absorbs the constituent desired to be estimated and
deducting the balance of gas or product left.
According to the invention the apparatus consists of a combination of two meters
or measuring appliances and a vessel containing suitable material for absorbing the
carbonic acid or other constituent desired to be ascertained. The operation of
estimating the carbonic acid in any gas-such as the products of combustion in
flues, consists in passing by means of; an aspirator consisting of a vessel in which
a vacuum is formed by withdrawing water therefrom; a bellows; a steam or
hydraulic ejector, or other suitable means; a current of the gases through the
apparatus, which is noted on the 1st meter; the carbonic acid is absorbed by the
absorber, and the balance of gases is noted by the 2nd meter and is thus
ascertained.
By varying the absorber or measuring the meters and absorbing vessels other or
additional constituents may be estimated in similar manner.
Dated this 21st day of November 1895.
D. F. MASON,
Glasgow, Patent Agent.
A New or Improved Apparatus for Estimating the Carbonic Acid or
other Constituents in Gases or Products of Combustion.
I GEORGE CRAIG, formerly of Lugar Iron Works, Cumnock, in the County of
Ayr, but now of 24 George Square, Glasgow, North Britain, 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:-
My said invention relates to a new or improved apparatus for ascertaining the
amount of carbonic acid or other constituents in gases or products of combustion
from coal or other material, by passing a given quantity of the said gases or
products through a material which shall absorb the constituent desired to be
estimated and measuring the balance of gas or product left; from which may be
deduced the efficiency of combustion.
The invention essentially consists in the combination of a gas measuring device
or meter for measuring the original volume taken; a close vessel containing material
11

page_text: which shall absorb carbonic acid or other desired constituent of the gas; and
another gas measuring device or meter for measuring the volume of unabsorbed
constituents.
I attain these objects by the apparatus illustrated in the accompanying drawing
which is a sectional elevation of an apparatus as constructed according to the
invention.
The apparatus comprises a gas meter 1, of ordinary well known construction,
having case T, an inlet pipe J¹ with stop-cock J and outlet pipe K₁ having
stop-cock K, leading and connected to the closed vessel U, fitted with a perforated
plate V near bottom leaving a space communicating with its outlet pipe L' having
stop-cock L thereon and leading to and constituting the inlet pipe to a second wet
gas meter 2, similar to aforesaid meter. The vessel, U is provided on top with a
charging screw cap C and near bottom with an emptying screw cap, (not shown)
for withdrawing the absorbing material when spent. Meter 2 outlet pipe N¹
having stopcock N, communicates with and is connected to main pipe O¹ having a
stopcock O between it and meter 1. Both said meters are each provided in front
with indices (not shewn) to conveniently show at least the 100th part of a revolution
of the measuring drum, R, over and above the usual registering mechanism. For
greater convenience the figuring on index dial of meter 2 may be reversed to show
directly the percentage of the absorbed constituent. Each meter has charging
plugs A, and gauging taps, B, both meters being charged with paraffin oil or other
suitable liquid having no absorptive action on the gases. By means of the plugs A
and taps B the meters are so charged and regulated that when a current of air is
drawn through, the indices exactly synchronize. The vessel U is filled by the
opening C with absorbent material, preferably soda-lime for carbonic acid. In
practice a slight suction is required to induce and maintain a current of gases
through the meters and absorbent material, as shewn by arrows; and which may
be conveniently accomplished, for prolonged action, by means of the well known
Bunsen water-pump or other water or steam ejector, connected to the end of main
pipe at m. For short trials, or where the use of said pumps or ejectors may be
inconvenient, the necessary suction may be obtained by an ordinary aspirating
tank having a charging inlet plug (not shown) and outlet tap y as shown. The
apparatus is connected and communicates with the flue Z by means of pipe p
sufficiently long to thoroughly cool the gases; the pipe Of and pipe p being
connected by any suitable coupling at 6.
The apparatus is operated as follows -By means of the aspirator or other
suction appliance a constant current of the gases from the flue Z is drawn along the
main tube O¹ of the apparatus and by gradually closing stopcock O as small a
current of gas as may be desired is caused to by-pass through the meters 1
and 2; the drums of which may conveniently revolve once in from two to
ten minutes. The indices of the meters are carefully read and noted at the
commencement and the finish of the trial. These readings give the initial and
final volumes of the gas, the difference representing the carbonic-acid or other
absorbed constituent in the initial volume, from which the percentage of absorbed
constituent is easily deducted. By simply reading at any time during the trial the
index of meter 2 at each complete revolution of the index of meter 1, the percentage
of carbonic acid or other constituent absorbed is obtained direct.
:-
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The arrangement and combination of apparatus substantially as and for the
purposes herein before set forth.
2. The combination of two gas measuring devices or meters, with a vessel
containing material which shall absorb the constituent desired to be estimated in
the gases passed from one meter to the other, substantially as and for the purposes
hereinbefore set forth.

page_text: 3. A gas analysis apparatus comprising two gas meters, a vessel containing
material which shall absorb the constituent desired to be estimated, and an
aspirator or suction pump or ejector, all combined and operating substantially as
herein before set forth.
Dated this 21st day of August 1896
DAVID F. MASON, C.E.,
Glasgow, Patent Agent.