Improvements relating to the Method of Charring Peat, Wood or the like, and to Apparatus therefor.
Year: 1897

page_text: Date of Application, 12th May, 1897-Accepted, 21st Aug., 1897
COMPLETE SPECIFICATION.
Improvements relating to the Method of Charring Peat, Wood or
the like, and to Apparatus therefor.
I, SVEN GUSTAF LAURENIUS, Engineer, of 28-30 West 9th Street New York City
New York, United States of America, 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 :—
The present method of charring or carbonizing peat, wood, or like materials, in a
retort consists in first removing from the mass the marsh water and all volatile gases
which cannot be retained. in the charcoal and, when the charring temperature has
increased and consequently the charring process progressed to the desired point,
letting in water or steam in the retort; for the purpose partly of interrupting the
charring process and partly of purifying and "slaking" the charcoal, by dissolving
and carrying away from the charred mass gases and soluble impurities, such as salts
or the like contained therein, and thus preventing spontaneous ignition when the
charcoal is pulled out of the retort as a completed product.
An apparatus adapted for carrying this method into practice is shown in the
accompanying drawing: in which
Figure 1 shows. a longitudinal section and
Figure 2 a cross section of the apparatus.
The receiver or retort 1, which is provided with a suitable cover for the
introduction of the material to be charred, is located in the usual manner above a fire
place, and the furnace gases are caused to circulate around the retort, being guided
by flanges 2 projecting from the latter and arranged zig-zag, or by partitions
projecting from the brick work, the preferable course for said gases being from the
centre towards the ends. The retort may be made in two halves lengthwise, or
conical like a char-stack. At the lower portion of the retort an outlet is arranged for
the gases formed, said outlet being suitably made in the shape of one or more slits 3
so located that the gases escaping under pressure through them will disperse over the
fire place and issue in horizontal directions underneath the retort. This may be
accomplished by allowing the escaping gases to strike against a bridge 4 at the centre
of the furnace. For preventing the gas-outlet from being stopped up by the
material treated, this outlet is, inside the retort, covered with a hood 5 under the
edges of which the gases can enter into a chamber 6 which communicates with
the slit. For discharging water or vapours from the retort at the beginning of the
charring process, the hood is provided with valves 7 and 8 through which the gases
are conducted from the chamber 6 into two compartments separated by a partition.
From one of these compartments a pipe 9 is carried out of the retort, while the other
compartment communicates with the slit 3. The valve 7 is lighter than the valve 8,
so that, by closing or opening a cock on the pipe 9 water or gas may be caused to
escape either through the slit 3 or through the pipe 9.
By the aid of a pressure gauge, a safety-valve and a pyrometer on the retort, and

page_text: by regulating the generation of gas and the intensity of firing it is possible with
some experience to control the process of the charring process.
At the upper
portion of the retort is attached a steam pipe or a small receptacle 11 for water,
which receptacle communicates at its lower end with the retort, by a pipe, there
being a cock 12 in this pipe and another cock 13 at the top of the receptacle, through
which cock the latter communicates with a funnel 14 for filling it. When the
carbonization has progressed to the point, where the charring process should be
stopped or in case the temperature in the retort for some reason or other should rise
too rapidly or too high, small quantities of steam or water are introduced from the
steam pipe or water receptacle 11 by opening the cocks, the temperature being thus
reduced. When the charcoal is ready, stean or water is also introduced for the
purpose of, so to speak, slaking the charcoal, .e., dissolving, by the application of
moisture, the combustible gases and soluble impurities retained in the pores of the
charcoal and replacing them by water, so that the charcoal will not be liable to
spontaneous ignition if it comes in contact with the outer air at a comparatively high
temperature. The common danger of the charcoal being burned up while being
taken out of the retort, or immediately afterwards, is hereby obviated, and a material
saving of time is effected for the next charring operation. As a result, the product
obtained by this method is both harder and purer than that hitherto obtained.
During the carbonizing process steam is first formed which is discharged from the
retort through the pipe 9, and subsequently gases are formed, consisting chiefly of
light and heavier hydro-carbons,. sulphuretted hydrogen, and other distillation
products of a similar nature.. These gases are discharged, together with the steam
formed, through the slit into the fire place where they are burned, thus serving to
heat the retort. From the combustion of the gases discharging into the fire place it is
also possible to judge of the progress of the process which is going on in the retort
and to tell when it should be interrupted. When the carbonization is done on a
large scale, it is preferable to combine two or more retorts, in which case the gases
from one of them may discharge into the fire place of another. In this case the pipe 9
may be inserted into the next retort in the manner shown for the connection of the
pipe 10 to the slit 3; By this means it will be possible to regulate the combustion
under any one of the retorts.
Practical experiments have proved the necessity, if a pure and firm charcoal is, to
be obtained, of locating the outlet for the gases at the lower position of the retorts,
since in the reverse case a cokelike product only was obtained..
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. In charring or carbonizing peat and like materials, the method of discharging
the heavier gases, formed during the carbonization, from the lower portion of the
retort employed and, when the charring process has progressed to the desired point,
introducing water or steam in the retort, for the purpose partly of interrupting the
carbonization, partly of purifying the charcoal from combustible gases and soluble
impurities, and partly of preventing spontaneous ignition of the charcoal when being
pulled out of the retort.
2. For carrying out the method specified in Claim 1, an apparatus consisting of a
retort having below one or more outlets or slits (3) for the discharge of the gases
generated in the retort, into the furnace, and being above provided with a pipe for
the introduction of steam or water.
3. In such charring or carbonizing apparatus as specified in Claim 2, valvės (7 and 8)
arranged inside the retort, at the outlet leading to the furnace, and separated by
partitions, which valves are of unequal weights the lighter one (7) serving to connect
compartments arranged so as to conduct the gases to a pipe (9), fitted with a cock,
through which pipe the gases pass out of the retort and outside the furnace of the
atter, if desired to the gas-outlet, leading from the interior of a second retort into its

page_text: furnace, while the heavier valve connects the interior of the retort with the gas-outlet
leading to the furnace, for the purpose of admitting of regulation of the discharge of
gas, from the retort into its furnace, by means of the cock and the pipe (9).
Dated this 12th day of May 1897.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.