IMPROVEMENTS IN THE PROCESS OF AND APPARATUS FOR DISTILLING PEAT AND OBTAINING BYE-PRODUCTS THEREFROM
Year: 1883

page_text: 1
PROVISIONAL SPECIFICATION left by Friedrich Carl Glaser at the Office
of the Commissioners of Patents on the 8th August 1883.
FRIEDRICHI CARL GLASER of Berlin in the Kingdom of Prussia and Empire of
Germany, Engineer and Patent Solicitor "IMPROVEMENTS IN THE PROCESS OF
AND APPARATUS FOR DISTILLING PEAT AND OBTAINING BYE-PRODUCTS THEREFROM
"
This invention relates to a process by means of which the combustible matter
contained in peat is converted into gaseous fuel for heating purposes, while at the
same time the bye products, such as ammonia, pyroligneous acid, tar, and hot air
are obtained thererefrom much more effectually than heretofore.
With the processes hitherto used for this purpose, no practically useful result
could be obtained, because the peat was either subjected to a coking process in
closed retorts at too high a temperature, or the distillation of the peat was effected
only with the view to obtain combustible gases.
In the present improved process, the essential feature of success consists in so
carrying out the operations as to carefully avoid the attainment of any high degree
of heat.
For the purposes of this invention a furnace or oven is employed consisting of a
series of vertical shafts, as shown at Gigs 1 and 2 of the accompanying drawings,
having at bottom a stepped grating or other form of grating, on which the
combustion of the peat, introduced at the upper end, is initiated. There is a large
and high space or chamber for the mass of incandescent peat formed by the
combustion in the lower part of the shaft in order, with the weak current of air
employed, to give the carbonic acid formed in the first instance, time to be
converted in the upper part of the chamber into carbonic oxide by contact with
the incandescent peat.
The partition walls of the shafts have, at a point about half way up, rows of
channels formed by hollow fire bricks which can be put in communication with an
exhaust for drawing off the carbonic oxide gas there formed.
The apertures are by preference so formed in the bricks as to be directed
downwards, in order to draw off the gases more from the lower part than from the
upper part of the shaft, and to prevent their becoming choked with the pent.
In the upper part of the shaft is an opening connected to a conduit or pipe for
leading off the gases generated to the cooler and scrubber which apparatus will be
presently described.

page_text: The partition walls are also provided with larger passages or flues in their upper
parts which are connected to a pipe for carrying off the heated air issuing
therefrom. By this arrangement, the twofold advantage is gained that the upper
part of the shaft is kept at the requisite low temperature for preventing any
decomposition of the ammoniacal gases, and that a supply of heated air is obtained
free of cost, for effecting the combustion of the combustible gases produced.
The shafts must be so charged with the peat that this only comes in contact with
the gases after these have been cooled to the greatest possible extent, and, for this
purpose, when the temperature rises above a certain point, the gases are drawn off
at the intermediate zone of the shaft as above described. In order also to keep
the temperature as low as possible, the draught is not allowed to exceed a higher
degree than is absolutely necessary, and is regulated for this purpose, as will be
presently described. By these precautions alone is it possible to prevent the
decomposition of the gases and vapors evolved, consisting of ammonia, acetic acid,
wood spirit, water, tar, etc.
The gases which serve to effect the distillation of the peat are generated in the
bottom of the shaft by the imperfect combustion of the carbonaceous residue after
distillation. The drawing off of the carbonic oxide gas at the middle zone of the
kiln is effected at as high a temperature as possible, and the hot gases are led
thence directly to the place of combustion, so us to utilize their heat as much as
possible. This leading off of the carbonic oxide at the middle zone is however
only effected when the temperature of the oven is too high, as already stated.
The gases distilled off from the peat are led from the top of the shaft through an
apparatus such as shewn at B, Fig. 3, wherein they are cooled by the air to such
an extent. as to cause the greater portion of tho tar, ammoniacal liquor, and other
condensible products to be condensed.
The gases are, for this purpose, made to pass in a zig-zag direction up and down
through sheet iron tubes offering considerable cooling surface to the atmosphere,
and having partitions-l dipping into the condensed liquor in the tank below, so as
to prevent the gases from passing directly through the latter.
The gases are then made to pass into the scrubber I, II, ascending through I and
descending through 11, while, at the same time, either the liquor condensed in the
cooler B, or water, is made to flow downwards from the tank above through the
parts I, II, being caused by the projecting inclined baffle plates to come into
-intimate contact with the gases and to take up therefrom the remaining condensible
ammoniacal and other constituents
By causing the liquor or water to flow in the contrary direction to that of the
gases in the compartment I, the draught of the oven from which the gases_come
is sufficiently checked, so that the downward draught in the compartment Il can
then be accelerated by an increased flow of liquid; and generally, the amount of
draught can be accurately regulated by regulating the flow of liquid through the
scrubber.
The gases passing from the scrubber, being practically freed from condensible
constituents, are then led directly to the locality where they are to be employed as
gaseous fuel for heating, or for other purposes, being made there to enter into
combustion with the before described heated air supply.
The main advantage of this improved process consists in obtaining the supply of
gaseous fuel free of cost, inasmuch as the bye products obtained not only repay
the cost of raw material, and of manufacture, and the interest of capital and
depreciation, but also, if the process is properly conducted, yield a considerablo
margin of profit.