Improvements in the Distillation and Decomposition of Coal, Shale, and other Matters to Obtain Illuminating Gas and other Products.
Year: 1886

page_text: Improvements in the Distillation and Decomposition of Coal,
Shale, and other Matters to Obtain Illuminating Gas and
other Products.
I HARTLEY KENYON of number 70 Barrett Street Manchester in the County
of Lancaster Manufacturing Chemist do hereby declare the nature of the said
Invention for IMPROVEMENTS IN THE DISTILLATION AND DECOMPOSITION OF
COAL, SHALE AND OTHER MATTERS TO OBTAIN ILLUMINATING GAS AND OTHER
"
PRODUCTS and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
My Invention relates to the distillation of coal, shale and other matters and to
the treatment of the same or of the products or residues or the employment of the
same to obtain illuminating and heating gases Ammonia, Benzole, Cyanides and
other useful products. In my process I prefer to use the ovens or apparatus which
I have described in the specification of another application for Letters Patent
bearing even date herewith but I do not confine myself to the use of such ovens
and apparatus. In the said apparatus or in an apparatus suitable for my purpose
ovens are erected in a range containing a suitable number of ovens which are
arranged to be worked in pairs the two ovens in a pair being provided with con-
nections whereby the gases from either oven can be passed into the other and also
with pipes and valves or cut off boxes whereby the gases or volatile products from
each oven can when desirable be passed into a waste pipe or into a gas main as
desired. The ovens are also built upon or provided with gas producers wherein
gas to beat the ovens is produced and with heating flues in which the gas is
burnt. In my process I employ superheated steam and this is obtained by heating
steam in pipes arranged in chambers situated below the ovens or such superheated
steam may be otherwise obtained.
For the purposes of my process I select such a quality of coal or slack, shale,
coke or carbonaceous matter as will furnish the desired products as for example
when the principal objects are to produce illuminating gas, ammonia and coke of
good quality I select coal slack, rich in Carbon, Hydrogen and Nitrogen as for
example a slack containing 75 to 80 per cent of Carbon 6 per cent of Hydrogen
or thereabouts and 2 per cent of Nitrogen or thereabouts may be used. From
this about 60 per cent of good coke may result after the gas and other products
have been obtained. When hydro-carbon oils are principally required a poorer
quality of coal or slack or suitable varieties of shale may be used. When it is
desirable to produce Cyanides I treat and use the coke in the manner hereinafter
set forth. When producing illuminating gas I charge one of the ovens in a pair
with the coal or slack. The oven which I will call oven N° 1 being provided with

page_text: charging openings in the crown the coal is charged from a travelling hopper or
wagon or by suitable means through these openings. The oven having been
heated previously to the charging steam is first given off and this I convey away
by opening the outlet for the same. When the gas begins to come off I close the
outlet for steam and open the passage which leads into the next oven which I will
call oven N° 2 and which is highly heated. In cases wherein I do not work the
ovens in pairs the gas may be conveyed into any suitable heated chamber which
may be provided with incandescent coke or with metal or other substances. In
practice the said oven N° 2 would contain incandescent coke resulting from the
distillation of a charge of coal but I am supposing it to be empty as when the
ovens are first started. The heat of the oven converts the paraffin and volatile
hydro-carbons coming over from oven No 1 into benzine and free hydrogen
whereby both the quantity and the illuminating power of the gas are increased
and also the quantity of resulting tar is lessened. The gas from No 2 is passed
into the illuminating gas main. When the distillation has proceeded until the
charge in oven No 1 is more or less incandescent N° 2 is shut off from N° 1 and
from the gas main and is charged with coal. When the steam has been discharged
as in the case of N° 1 the communication with the latter is opened so that the gas
passes from N° 2 into N° 1 wherein the heated oven and the hot coke therein have
the before mentioned effect upon the paraffin and hydro-carbon. The free hydrogen
produced absorbs nitrogen by contact with the hot or incandescent coke and
ammonia is produced. As the coke in No 1 becomes more incandescent super-
heated steam is conveyed into the body of coke therein and being highly heated
absorbs or takes up the sulphur from the coke. During this part of the operation
I inject by means of superbeated steam a spray of paraffin or other hydro-carbon
oil into Nº 2 and this passes over with the gases into No 1 or is partly decomposed
in No 2 and partly passes into N° 1. This paraffin is converted into benzine
and hydrogen whereby both the volume and the illuminating power of the
gas are increased. Although I prefer to pass the paraffin through both ovens a
suitably good result might be obtained by discharging it directly into the oven
containing the incandescent coke that is to say into oven N° 1. The quantity
of paraffin so used may amount to about one sixteenth of the weight of the
coal. The gas is passed from oven N° 1 into the illuminating gas main.
When the operation has been carried as far as is considered to be desirable the coke
is withdrawn from N° 1 and the oven is re-charged. After the steam has been
discharged the gas is again passed over into N° 2 which will then be charged with
coal and the operations are repeated superheated steam being discharged into N° 2
and paraffin into N° 1. The coke withdrawn will be commercially free from
sulphur. In cases wherein the gas is required for heating purposes only, super-
heated steam alone without the paraffin is discharged into the last charged oven
and passing into the other oven prevents or checks the decomposition of the
ammonia and in such cases when the production of heating gas or of ammonia is of
more importance than the resulting coke I continue the operations until there is
about six hundredweights of coke for each ton of coal or as long as may be con-
sidered to be desirable. The heating gas produced is conveyed into the heating or
water gas main. In the making of heating gas I convert about 90 per cent of the
nitrogen into ammonia. When the resulting coke has been withdrawn I quench it
with an alkaline solution such for example as a solution of caustic or carbonate of
soda or potash and I charge this coke into the chambers in which the gas for
heating the ovens is produced or into a suitable oven or furnace. The coke
becoming incandescent superheated steam and highly heated air are passed through
the coke and the nitrogen in the air combining with the alkali produces a cyanide
of sodium or potassium as the case may be and such salt may be obtained by
lixivation after removal of the ashes from the chamber, or as an alternative before
withdrawing such coke or residue from the chamber I may pass superheated steam
alone through the coke whereby the cyanide or cyanides would be decomposed
and ammonia be liberated and passed to the gas washers. The alkali would be

page_text: recovered from the ashes by lixiviation and might be used again. I may mix
alkali in the state of salt with the coke in order to obtain a larger proportion of
the cyanides. The ovens may be fitted with both heating and illuminating gas
mains or with one, or the other according to the requirements or certain of the
ovens in a range may be used to make heating gas and others illuminating gas.
The heating gas so produced may be used in the heating of the ovens or for other
purposes. I prefer however to obtain the gas for heating the ovens from gas
producers formed below the ovens. The illuminating gas is passed into a washer
wherein it is treated with ammoniacal liquor so as to charge it with an excess of
ammonia. The ammonia sulphides and carbonates are subsequently removed by
washing with water. I prefer to deprive the ammoniacal liquor of carbonic acid
before using it in the gas washer. I pass the liquor from the gas washer to a
tower into which I discharge ammoniacal steam derived from stills in which
I concentrate ammoniacal liquor. The vapour from the said tower charged with
ammonia sulphuretted hydrogen and carbonic acid may be passed into a sulphuric
acid chamber to receive ammonia or may be utilised along with the carbonic acid
from the ammoniacal liquor washer (in which the said liquor is deprived of
carbonic acid) in the decomposition of salt brine in the manner set forth in the
specification of a former invention for which Letters Patent numbered 4951 of the
year 1883 have been granted to me.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
1. The process of making illuminating gas wherein paraffin or hydrocarbon oils
and superheated steam are discharged into the distilling ovens at certain stages in
the process substantially as and for the purpose set forth.
2. The process of making illuminating gas wherein distilling ovens are worked in
pairs the gases from the last charged oven in a pair being passed into the other
oven paraffin or hydrocarbon oil being injected into the last charged oven and
superheated steam into the other oven substantially as and for the purposes set
forth.
3. In the manufacture of water or heating gas by the discharge of superheated
steam through incandescent coke discharging an additional supply of super heated
steam into the upper part of the oven above the coke in order to increase the yield
of ammonia substantially as set forth.
4. The production of cyanides by quenching or treating coke with alkali or
alkaline solutions by rendering such coke incandescent in a suitable chamber or
furnace and by passing superheated steam and heated air through such coke the
cyanides being recovered from the ashes substantially as set forth.
5. In the production of gas for heating purposes and ammonia treating coke with
alkali or alkaline solutions rendering the same incandescent passing through the
same superheated steam and heated air as in the foregoing clause and then passing
through the body of such incandescent coke superheated steam alone, gas charged
with ammonia passing off substantially as set forth.
6. The combined processes and operations working in concert for the production
of gases, ammonia, coke and useful products substantially as hereinbefore set forth.
Dated this 22nd day of January 1886.
DUTTON & FULTON,
Agents.