Year: 1899

page_text: Date of Application, 1st Mar., 1899
Complete Specification Loft 1st Jan 1000
Accented 2nd Coh
1000
A communication from EMIL FLEISCHER, Chemist, of 32, Thiergartenstrasse,
Dresden-Strehlen, in the Empire of Germany.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of London,
Chartered Patent Agent do hereby declare the nature of this invention to be as
follows:
When steam is carried over coal fire at a very high temperature, say 700 to
9000 decomposition is effected as regards the greater part of it according to the
equation 2H2O + C CO24H, evolving H + CO₂ (1). At higher temperatures
however it is known that the combination H+CO (water gas) is evolved accord-
ing to the equation H₂O + C CO + 2H (2).
=
It has been found by my correspondent to be more economical and convenient
for working, especially as regards economy in steam expenses and uniform qual-
ity of the gas, to work in such a manner that the decomposition of the steam is
carried out in a generator according approximately to equation 1, the gases then
passing into a hotter generator in which they are changed into water gas proper
(containing but very little CO₂).
It has also been found that with the exception of coke and anthracite, bitu-
minous coals are very well adapted for such an arrangement of two generators,
making use of the special adaptability of such coal, by thus distilling the same.
If the process is so carried out that the steam is caused to enter from below,
that is to say in the same direction as the air, into one of two generators, which
are connected with air ducts above and below, and causing the steam to enter the
second generator from above directing the steam in the second generator down-
wards, that is to say against the heated air current which is passed through the
apparatus for the purpose of heating it, and by charging the first generator with
coal before steam is admitted; two advantages are secured. The gas formed
in the first generator passes into the second, through the upper colder strata to the
hottest strata below. Thus the heat is advantageously employed and all the
carbonic acid gas is changed into carbonic oxide.
Further, gas is also distilled from the fresh charge of coal by means of the
heated gases passing through the charge; such new gas being also changed into
permanent water gas in the second generator as it passes from the top to the
bottom, through the gradually increasing degrees of heat, by which the formation
of tar is avoided. A practical arrangement of the whole process, which is inde-
pendent of any specially constructed generator, is as follows:-
Coke or carburised fuel is placed in two generators and one of the generators,
which shall be called A, is heated to a lesser temperature, say 900° C., while the
other B is heated to say 1100° C., the colder generator is charged with coal, and
steam is admitted. This steam is decomposed in the manner above described,
and the evolved gases CO₂+4H, as well as the particles of non-decomposed steam,

page_text: or of CO, pass through the fresh charge evolving from it the new products of
distillation. The mixed gases then enter the second generator, B, and pass
through it from top to bottom. In this passage CO₂ is reduced, and the products
of distillation decomposed, whereby water gas issues from the bottom of the
generator. During this operation the first generator A is cooling down, say
to 700° C., while the second B will hardly have cooled below 900° C.
Now the steam and water gas conduits are closed as soon as it is found that the
issuing gas does not correspond to the required conditions, the connecting chan-
nel between the two generators being also closed, and the first generator A is
again heated by a hot blast.
It is heated to a temperature of say 1100° C. and hence the same conditions
are re-established, as, at the beginning, only that the first generator A has
changed places with the second B as regards temperature.
After having charged the second generator 13 with coal, steam is caused to pass
through it, and the process of production of water gas is carried on as before.
As will be understood it is possible to charge the first generator A with coal
sooner than has been indicated above, that is to say, before or at the same time
that it is heated by means of the hot blast. This process can also be combined
with the Dellwik gas process, such as described in British Patent No. 29863 of
1896. According to this invention such a quantity of air is made to pass from
below into the generator (calculated according to the heighth of the layer of
burning material) whereby the products of combustion may result in as much
carbonic acid gas as possible, at any rate more carbonic acid gas than oxide of
carbon.
Datalie 1st day of Vevel 1899
BOULT & WADE,
Agents for the Applicant.
A communication from EMIL FLEISCHER, Chemist, of 32, Thiergartenstrasse,
Dresden-Strehlen, in the Empire of Germany.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of London,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
When steam is carried over coal fire at a very high temperature, say 700 to
900° decomposition is effected as regards the greater part of it according to the
equation 2H2O + C = CO₂+ 4H, evolving H + CO, (1). At higher temperatures
however it is known that the combination H+CO (water gas) is evolved accord-
ing to the equation H₂O + C CO + 2H (2).
=
It has been found by my correspondent to be more economical and convenient
for working, especially as regards economy in steam expenses and uniform qual-
ity of the gas produced, to work in such a manner that the decomposition of the
steam is carried out in a generator according approximately to equation 1, the
gases then passing into a hotter generator in which they are changed into water
gas proper (containing but very little CO₂).
It has also been found that not only coke and anthracite but also bituminous
coals are very well adapted for such an arrangement of two generators, the special

page_text: difficulties of such coal being overcome by thus distilling the same, and convert-
ing it into coke after it has been charged.
The process is preferably so carried out that the steam is caused to enter from
below into one of two generators and that the products produced in this generator
pass over to the second generator and enter into it at its top. The gas formed in
the first generator passes into the second, through the upper colder strata to the
hottest strata below. Thus the heat is advantageously employed and all the car-
bonic acid gas is changed into carbonic oxide.
Further, gas is also distilled from the fresh charge of coal by means of the
heated gases passing through the charge; such new gas being also changed into
permanent water-gas in the second generator as it passes from the top to the
bottom through the gradually increasing degrees of heat, by which the forma-
tion of tar is avoided. A practical arrangement of the whole process, which is
independent of any specially constructed generator, is as follows:-
Coke is placed in two generators, and one of the generators, which will be
called A is heated to a lesser temperature, say 900° C., while the other B is
heated to say 1100° C., the colder generator is charged with a stratum of coal,
and steam is admitted into it. This steam is decomposed in the manner above
described, and the evolved gases CO₂+4H as well as the particles of non-decom-
posed steam, or of CO, pass through the fresh charge evolving from it new pro-
ducts of distillation. The mixed gases then enter the second generator B, and
pass through it from top to bottom. In this passage CO₂ is reduced and the pro-
ducts of distillation decomposed, whereby water-gas issues from the bottom of the
generator. During this operation the first generator A is cooling down, say
to 700° C., while the second B will hardly have cooled below 900° C.
Now the steam and water gas conduits are closed as soon as it is found that
the issuing gas does not correspond to the required conditions, the connecting
channel between the two generators being also closed, and the first generator, A,
is again heated by a blast to a temperature of, say, 1100° C., and hence the same
conditions are re-established, as at the beginning, only that the first generator A,
has changed places with the second B, as regards temperature.
After having charged the second generator, B, with coal, steam is caused to
pass through it, and the process of production of water gas is carried on as before.
As will be understood it is possible to charge the first generator A with coal
sooner than has been indicated above, that is to say before or at the same time
that it is heated by means of the blast. This process can also be very advan-
tageously combined with the Dellwik gas process such as described in British
Patent No. 29863 of 1896. According to this invention such a quantity of air
(calculated according to the height of the layer of burning material) is made
to pass from below into the generator that the products of combustion may result
in as much carbonic acid gas as possible at any rate more carbonic acid gas than
oxide of carbon.
Having now particularly described and ascertained the nature of the said
invention, as communicated to me by my foreign correspondent, and in what
manner the same is to be performed, I declare that what I claim is:-
1. The production of water gas in twin generators by first heating the genera-
tors to different temperatures, adding coal to the less highly heated generator,
then passing steam through this generator in the same direction as the blast used
for heating it, the gases evolved thereby then passing through the second genera-
tor in the opposite direction to that of the air blast previously driven through
it for the purpose of heating it, substantially as described.
2. A modification of the process described for the purpose of producing differ-
ent temperatures in both generators consisting in alternating the course of work
in such a manner that one generator, after having been heated by a blast, and
before being re-heated, is employed first for the second phase of the process and

page_text: then for the first phase of the following operation only the less highly heated
generator through which steam had been first passed being re-heated by a hot
blast after every completed gas period, the other generator from which the water
gas was finally evolved at the last gas period and which is not then re-heated
by a hot blast receiving the steam current for the next generation of gas sub-
stantially as described.
3. A modification of the process described, in which the air blasting phase of
it is carried out according to British Patent No. 29863 of 1896.
Dated this 1st day of January 1900.
BOULT, WADE & KILBURN,
Agents for the Applicant.