Improvements in the Methods and Appliances for Drying Moist Material, for instance, Newly Formed Bricks, Pipes. Flags, and such like, by Means of Artificial Heat.
Year: 1891

page_text: Date of Application, 20th Apr., 1391-Accepted, 23rd May, 1891
COMPLETE SPECIFICATION.
Improvements in the Methods and Appliances for Drying Moist
Material, for instance, Newly Formed Bricks, Pipes. Flags, and
such like, by Means of Artificial Heat.
I, GUSTAV WEIGELIN of 5 Sennefelderstrasse, Stuttgart, in the Empire of
Germany, Civil Engineer, 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 :-
This invention has for its purpose to artificially dry moist material, earths,
freshly formed bricks, pottery goods and the like in such a manner as to allow
the work in brick works, potteries, cement factories etc. to be uniformly carried
on all the year round regardless of the winter, when climatic influences render
the drying of said materials in the open air difficult or impossible. It is
important that the fuel used for the said drying process be utilized as completely
as possible and that the drying be effected in a relatively short time, but never-
theless in such a manner as to avoid rupture of the bricks or objects to be dried.
These advantages are attained by causing the heating of the materials in the
drying chambers to take place gradually i.e. to increase from chamber to chamber
and by carrying out the drying process by introducing the heating and fire gases
and the heated air from above, so that the steam generated is absorbed by the
smoke and passed into the chimney.
Referring to the accompanying drawing representing a system of 8 drying
chambers (No. 1 to VIII) as longitudinal oven with intermediate "closcable
middle passage,
Figs. 1, 2 and 4 are vertical sections, and
Fig. 3 is a plan of said system.
C
The chambers a lying on the right and left of the middle passage have
furnaces which are served from the said passage. From furnaces the fire or
heat is conducted into the chambers through passages d d provided underneath the
drying chambers and through the vertically extending continuations of these
The smoke substance
passages, which terminate direct below the vaulting.
transmits its heat to the chamber, is saturated with the steam generated from the
moist drying material contained in the chamber and flows through smoke passage e
into the smoke accumulator y whence it escapes through flue into the atmosphere.
The middle passage is in direct communication through passage n with the
atmospheric air and can also be placed into circulating connection with each
chamber through the "closeable" door openings m and m.
The adjoining chambers a a communicate with each other through circulation
apertures provided at the bottom and at the vaulting and adapted to be tightly
closed by means of slides. In order to effect a circulation passage through the
whole chamber system, each two end chambers which lie on the right and left of
the middle passage are connected with each other by circulation passages and P
adapted to be closed by means of bells and slides. The furnaces e communicate
through channel p.
As mentioned above, the drying takes place with gradually increasing heat in
the corresponding chambers in such a manner that of four chambers one only is
actually heated, one is being cooled and the two other chambers receive their heat
When for instance
from the heated chamber and from that to be cooled.
chamber VIII is cooling (by the air of the middle passage circulating through this
chamber when doors m and m' are opened) and chamber I is being heated, the
adjoining chamber which is already somewhat heated derives its heat from

page_text: b
chamber through the circulation apertures ii, while chamber III is heated by
the superfluous (because being cooled) heat passing from the opening m¹ which
terminates at the top of chamber VIII in passage into the closed middle passage b,
whence it enters chamber III through opening m' thereof which likewise terminates
in said passage. From chamber 11, the heated air flows through the heating
channels d d and furnace e downward into passage pand is hence conducted as
preliminarily heated feeding air to the furnace of the heated chamber I.
Chamber I therefore receives the first heating by ventilation by means of air
heated by the cooling of chamber VIII, while chamber 11, which has already been
heated in this way, receives the second increased heating by circulation from
chamber, and the latter derives the maximum heating from the fire of the
furnace.
In the same manner as the chambers VIII, I, II and III form one working
series, the chambers IV, V, VI and VII co-operate, cooling taking place in
No. IV, heating in No. V slight preliminary heating in No. VII and increased
preliminary heating in No. VI. When chambers VIII and IV are cooled, they
are emptied and filled afresh and now and V are cooled, 11 and VI heated and so
forth. The process advances each time by one chamber. Any suitable number of
chamber rows may of course be employed according to requirement. Nor are
there exactly four chambers required for one working row, but corresponding to
the material to be dried and to the aqueous contents thereof and to its susceptibility
with regard to rupturing the chamber row may be increased by a chamber or
chambers. Or the intensification of the heat in the heated chamber may be
increased or reduced, the saturation of the vapour to a certain rational extent
being always taken into consideration.
By the more energetically acting ventilation being always conducted over the
moist material to be dried instead of through the same, the danger of injury by
rupture to susceptible material is removed; the more slowly acting circulation
does no harm to the objects and is moreover capable of regulation by means of the
slides.
The heating channel conduction interrupted in the chamber allows the smoke,
notwithstanding its short way within the chamber itself, to be deprived of a great
portion of its heat, as it communicates its heat more rapidly by direct contact with
the sides of the chambers than if it were transmitted through heating tube sides..
The direct supply of smoke to the chambers admits moreover of a drying
without admixture of air, the smoke absorbing and removing the steam, whereby
the introduction, heating and removal, by ventilation, of large quantities of air is
avoided and consequently great economy in the consumption of fuel effected.
The arrangement of two rows of chambers with middle passage adapted to be
closed, together with the other firing, channel-, and regulating devices allows
of the most complete utilization of the fuel, especially of the recovery of the heat
of the dried material or objects.
It is only by means of complete utilization of heat, which is attained in the
improved arrangement, that artificial drying becomes advantageous in practice.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1) Process for drying--in continual operation, moist masses or objects by
means of artificial heat, characterised by the application of gradually increasing
heat by means of upper current, or circulation, or by means of upper current
and circulation in each of the drying chambers a, which are adapted to be so
placed into connection with each other and with a middle passage & by openings
capable of being regulated and closed, that
b
the incipient drying of the newly introduced material is effected by an
upper current-conducted over the material of the heat recovered from
the chamber to be cooled.

page_text: If the preliminary heating of the material already incipiently dried takes place
by circulation and by the directly heated chamber, and
III the final or finishing drying of the preliminary heated materials is effected
by an upper current-conducted over the material to be treated-of the
heat generated by direct heating as well as by circulation with the con-
tiguous chainber to be preliminarily heated, the whole substantially as and
for the purpose set forth.
) Drying chamber arrangement, for carrying out the process forming the
ject of Claim 1, for continual operation, by gradually increased heating of
mbers placed in juxtaposition, said arrangement being characterised,
1 by the fresh air conducted from outside through air channels n to the middle
passage cooling the dried hot chambers by entering through openings m into
these chambers subsequently flowing in a heated state through openings m³
into the middle passage and hence through m' into the freshly filled chambers,
to which it gives their first heating, and whence it is conducted through
channels and p as feeding air into the heated furnaces;
II by the fire gases passing through the fire passages d and arriving from
above into the chambers, which are adapted to be connected to one or
more working series by means of "closeable" circulation openings ii and
channels in such a manner that of one working series always one chamber
only is heated while the contiguous chamber which has already undergone
its first heating, receives its second heating by circulation from the heated
chamber of the same series, and the heated chamber itself finally dries by
the firing, by which combination of a number of working series a working
advancing continually by one chamber is rendered possible, the whole
substantially as illustrated and described.
Dated this 20th day of April 1901.
G.
WEIGELIN.
By Huelser & Co.,
Temple Chambers, London, his Agents.