IMPROVEMENTS IN THE DRYING OF MALT AND IN THE CONSTRUCTION OF MALT-KILNS THEREFOR;
Year: 1885

page_text: I, MAX HEDICKE, of 3, Adelaide Place, London Bridge, London, E.C., Mer-
chant, do hereby declare the nature of my invention for IMPROVEMENTS IN THE
DRYING OF MALT AND IN THE CONSTRUCTION OF MALT-KILNS THEREFOR; to be as
follows:-
The various methods of drying malt, as they are at present practised, show long
felt faults, and the quality of the malt, thereby produced, leaves much to be
desired.
Where there is only one drying-floor the quantity of the grain that can be
malted at a time is limited, and, therefore, the danger arises of over-hastening the
drying-process to the disadvantage of the quality of the malt to be produced.-
It further tends to overload the kiln-floor, which is wrong, for with great thickness
the drying of the lower part of the grain saturates the upper portion with
moisture, and if the grain is turned, that part of it, which was partly dry, will
be re-moistened. Thus the drying-process is prolonged, and more especially the
time during which the grain is submitted to a low damp heat, favourable to the
development of acidity.
If, on the other hand, two floors, as they are at present generally constructed,
are in use, it is quite impossible to expose the moist green malt, on the upper floor
during the first stage of the malting-process, to a sufficiently good draught to
quickly carry away the vapour thrown off.-Besides the danger arises of exposing
the green malt too early to too high a temperature, as the hot air, after passing
through the lower floor, where it is required at a high temperature, acts directly
on the upper floor, respectively on the moist green malt upon it, the result
frequently being that the grain, resting immediately on the kiln-floor, is vitrified
or hardened exteriorly before the moisture can escape from its centre. At the
same time a great part of the moisture, carried off by the ascending air from the
grain on the lower floor, condenses again while passing through the grain on
the upper floor, from where it has to be evaporated a second time under conditions
favourable to the development of acidity.
In some malting-houses again the mistake is made of not exposing the malt
during the drying-process, and more especially during the latter part of it, to the
actual products of the combustion of the fuel, thereby not imparting to it the
distinguishing empyreumatic flavour and preserving qualities.
In order to overcome these faults I construct a malt-kiln with two kiln-floors,
lying above each other, in such a manner as to give to the upper floor its own
independently conducted supply of heat and its own ventilation, thus allowing of

page_text: separately controlling the temperature of the upper floor, and of conducting the
drying-process on the same independently from that on the lower floor. Both
floors are heated from the same furnace, in which the kiln-fire is so placed that the
products of the combustion of the fuel gain access to at least the malt on the lower
floor. I separate both drying-floors from each other by means of a ceiling, placed
at a suitable distance above the lower and underneath the upper floor, or by some
similar means of separation, thus preventing the hot air, which passes through the
lower floor, from directly acting on the upper floor.-I preferably lead this air
(after having passed through the lower floor and the malt thereon) directly off by
means of a chimney (or ventilator), passing straight through the middle of the
upper floor, or, in order to save space on the upper floor, by means of shafts leading
through the interior of the outer walls, and passing out at the top of the building
through a ventilator which encircles the ventilator of the upper floor. However,
this hot air, after having passed through the lower floor, may be also made use of,
in a suitable manner, for heating the air intended for the drying on the upper floor.
The heating of the upper floor can take place in various ways. For instance
hot air can be led from the furnace, or from the hot-air-chamber underneath the
lower floor, through pipes, or through shafts leading through the interior of the
outer walls, or by some other means, into the space underneath the upper floor and
above the separating ceiling, or this said ceiling may be made of some heat-
conducting material, for instance of corrugated metal, in which case the air-above
.it would get heated through the influence of the hot air underneath, as the latter,
after its passing through the lower floor, would act on the separating ceiling. Nor
do I exclude the introduction of this hot air, after having passed through the lower
floor, into the space above the separating ceiling. Finally the heating can take
place through a combination of these various methods, or through a combination of
such as are found desirable for the purpose, or by some other suitable means.
The ventilation of the upper floor, which is also independent from the ventilation
of the lower one, can be arranged in whatever manner desired, provided the
arrangement answers the purpose for which it is intended.-I preferably employ
openings or air-shafts in the outer walls of the kiln, which allow the admission of
fresh air into the space underneath the upper floor and above the separating
ceiling, whenever desired, and construct an independent vent at the top of the kiln
for carrying away the moisture thrown off. I preferably construct this ventilator
round, respectively inside, the one which carries off the moisture thrown, off from
the malt on the lower floor, and surmount both by a cowl.
For the purpose of better mixing and evenly distributing the air, intended for
the first drying of the green malt on the upper floor, I place a heat-disperser (or
a set of dispersers) between the upper floor and the separating ceiling in some
similar manner as such are in various shapes employed, underneath the lower,
respectively single, floor of kilns, or in some other suitable shape.
The management of the first stage of the drying-process (on the upper floor) is
thus rendered quite independent from the conducting of the drying on the lower
floor, and the ventilation and temperature on the upper floor are kept under
perfect control and can be raised or lowered according to the variety of malt
required.
Green malt being very voluminous, and it not being desirable to load the upper
floor higher than can be helped, I build this floor, if possible, larger than the lower
one, which can be effected either by diminution of the upper walls, or by limiting
the size of the lower floor.
It not being always practicable to make the malting-house square, it may be
built of a greater length than width, and it may in such cases be provided with
two fire-places instead of one, and with two double ventilators instead of one.
A malt-store can be advantageously constructed in the lower part of the building
round the furnace or furnaces.
It is not my intention to restrict the application of thus dividing the kiln-
drying-process into independently from each other conducted stages to kilns with

page_text: two floors, but this system can also be applied to kilns with three floors, by either
conducting the drying-process on each floor independently from the others (in
which case one separating ceiling has to be placed above the lower and another
above the middle floor, in combination with a modified arrangement for heating
and ventilation, upon the principle heretofore set forth), or by only giving to the
upper floor, intended for the first drying-stage of the malt, an independently
conducted supply of heat and ventilation, while the two floors underneath are
constructed in a similar style as the two-floor-kilns now in use, allowing the hot air,
after having passed through the lower floor, to pass directly through the middle
one. As there is virtually no moisture left in the malt, when it is passed on to
the third and lowest floor; no harm can possibly be done to the malt on the
middle floor through the action of the hot air ascending from the lower one, nor is
there any danger of vitrifying the malt on the middle floor, as it has securely
passed that stage on the upper floor. (Here the separating ceiling would, of course,
be situated above the middle and underneath the upper floor).-I prefer this latter
construction for Three-floor-kilns; and they can be used to special advantage
where the drying of the particular kind of malt, to be produced thereon, has to be
finished at a very high temperature, or where it is desired to prolong the drying-
process without decreasing the quantity of malt to be produced within a certain
time.
In Three-floor-kilns the green malt is first to be placed on the upper floor, is
afterwards passed on to the middle one, and the drying is finished on the lower
floor, the heat from floor to floor increasing, while with Two-floor-kilns the drying-
process begins on the upper floor and is finished on the lower one, without any
intermediate stage.
Existing kilns can be altered to my system, and I recommend to leave them, as
far as practicable, in their original form, by simply building the floor, intended for
the reception of the green malt, on the existing structure, and using the existing
roof, if suitable, as medium for separating the upper floor from the lower floor or
floors. The existing chimney, or ventilator, for carrying off the moisture, is best
led through the new floor, passing at the top right through the independent
ventilator of the new floor, the latter encircling the former.-Some suitable
alteration for the independent supply of heat to the new floor, upon the principle
previously described, would, of course, be required, and here I wish to point out
that I do not mean to make it a necessity that the malt on the upper floor,
respectively on the upper and middle floors, should come into contact with the
actual products of combustion (although this may be the case if the arrangement
for heating the upper floor allows of it), but I make it an absolute condition that at
least the malt on the lower floor should do so.
The purpose of my invention is to improve the process of kiln-drying malt by
first partly drying the malt on a floor which has its own independently conducted
supply of heat and its own ventilation, and by afterwards passing the malt on to
one or two more floors for the finishing of the drying-process, allowing the actual
products of the combustion of the fuel to gain access to at least the malt on the
lower floor, as more fully described heretofore.
The combination of the peculiar style of conducting the first stage of the drying-
process on a floor, which has its independently conducted supply of heat and its
own ventilation, with the finishing of the drying-process on the lower floor, under
the influence of the actual products of the combustion of the fuel, forms a promi-
nent feature of my invention, and great advantages with regard to the quality of
the malt thus produced will be derived from it.

page_text: Improvements in the Drying of Malt and in the Construction
of Malt-kilns therefor.
I, MAX HEDICKE, of 3, Adelaide Place, London Bridge, London, E.C., Merchant,
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 various methods of drying malt, as they are at present practiced, show long
felt faults, and the quality, of the malt, thereby produced, leaves much to be
desired..
...
Where there is only one drying-floor the quantity, of the grain that can be
malted at a time is limited, and, therefore, the danger arises of over-hastening the
drying-process, to the disadvantage of the quality of the, malt to be produced.
It further tends to overload the kiln-floor, which is wrong, for with great
depth the drying of the lower part of the grain saturates the upper portion with
moisture, and if the grain is turned, that part of it which was partly dry will be
re-moistened. Thus the drying-process is prolonged, and more especially the
time during which the grain is submitted to a low damp heat, favorable to the
development of acidity.
If on the other hand two floors, as they are at present generally constructed, are
used, it is quite impossible to expose the moist green malt on the upper floor
during the first stage of the drying-process to a sufficiently good draught to
quickly carry away the moisture thrown off, as the ascending air. has already lost
the better part of its power. by its passage through the malt on the lower floor,
and only arrives at the upper floor after having already absorbed a considerable
quantity of moisture. Besides the danger arises of exposing the green malt too
soon to a high temperature, as the hot air, after passing through the lower floor,
where it is required, at a high temperature, acts directly on the moist green malt
upon the upper floor, the result frequently being that the grain resting immediately
on the kiln-floor is vitrified or hardened externally before the moisture can escape
from its center. At the same time, a great part of the moisture, carried off by the
ascending air from the grain on the lower floor, condenses again while passing
through the grain on the upper floor, from where it has to be evaporated a second
time, under conditions most favorable to the development of acidity, and thus not
only wasting fuel but seriously endangering the quality of the malt.-This danger
even increases in cases where the green malt on the upper floor is loaded too deep,
thereby still more interfering with the free passage of the ascending hot air, the
effective action of which is already limited by its passage through the malt on the
lower floor, as mentioned before.
In some malt-houses again the mistake is made of not exposing the malt during
the drying-process, and more especially during the latter part of it, to the direct
action of the products of combustion, thereby not imparting to it the peculiar
empyreumatic flavour and preserving qualities.
In order to overcome the faults of these various systems, heretofore mentioned,
I construct a malt-kiln with two kiln-floors, one above the other, but separate both
floors from each other by means of a divisional structure of any suitable shape (for
instance that of a dome, or roof, or ceiling), placed at a proper distance above the

page_text: lower and underneath the upper floor, thereby forming what may be called a
special air-chamber for the latter floor.-This divisional structure may be made of
any suitable material.-I give to the upper floor its own independent supply of
heat and its own ventilation, thus allowing of separately controlling its tempe-
rature, and of conducting the drying-process on the same independently from that
on the lower floor.-Both floors are heated from the same furnace (or furnaces),
which must be constructed in such a manner as to allow the actual products of
combustion to gain access to at least the malt on the lower floor.-I intentionally:
do not mean to make it an absolute, necessity that the products of combustion
should come into contact with the malt on the upper floor, as, firstly, I do not
consider it of primary importance, and, secondly, the furnace might possibly be
constructed in such a manner as to avoid this.
In separating the upper floor from the lower one by means of some divisional
structure between the two, I prevent the hot air, after passing through the lower
floor, from directly acting on the upper one.-I preferably lead this air (after
having passed through the lower floor and the malt thereon) directly off by means
of a vent-pipe (vapor-escape, chimney), passing from the highest part of the
divisional structure straight through the middle of the upper floor, and ending at
the top of the building inside the air-outlet of the upper floor.-In order to save
space on the upper floor this air may be also led off by means of shafts leading
from the highest point of the divisional structure through the interior of the outer
walls, entering these walls underneath the upper floor and passing out at the top.
of the building through an outlet which in this case encircles the air-outlet of the
upper floor. Or this hot air after having passed through the lower floor, may be.
also made use of in a suitable manner for heating the air intended for the drying
on the upper floor, as I describe more fully hereafter.
The heating of the upper floor can take place in various ways. For instance
hot air can be led from the furnace, or from the hot-air-chamber underneath the
lower floor, either through pipes, or shafts leading into the space underneath the
upper floor and above the divisional structure, or this said structure may be made of
some heat-conducting material, for instance of corrugated metal which presents a
large heating-surface, in which case the air above it gets heated through the
influence of the hot air underneath, as the latter, after passing through the lower
floor, acts on the divisional metal-structure. Nor do I exclude the introduction
of this hot air (after having passed through the lower floor) into the space above
the divisional structure for the purpose of utilizing the same for the drying on the.
upper floor, as here it would be newly prepared for the drying-process by its.
mixing with the additional supply of cold air, the latter respectively in combination
with a new supply of hot air, both being introduced into the space between the
two floors by means of those special inlets peculiar to my system. This will be
better understood through my description hereafter. The introduction of such air
(after having passed through the lower floor) into the space above the divisional
structure can take place in various ways, for instance there could be some open
space left round the divisional structure, allowing part of this air to enter above
the structure while the greater part would be carried off through the vent-pipe at
the top of the structure, or this vent-pipe may be dispensed with altogether and
the divisional structure broken through in various places, so as to allow all this air
to enter into the space above it.-Here, however, I wish to point out that I prefer
the previously mentioned system of leading all the hot air from the lower floor
directly off. Finally the heating can take place through a combination of these
various methods, or through a combination of such as are found desirable for the
purpose, or by some other suitable means.
The ventilation of the upper floor can be arranged in whatever manner desired,
provided the, arrangement answers. the purpose, for which it is intended. I pre-
ferably employ air-shafts, or openings in the outer walls of the kiln, which allow, of
admission of a sufficient volume of fresh cold air into the space underneath the
upper floor, and above the divisional structure, and construct, an independent vent

page_text: at the top of the kiln for carrying away the moisture thrown off. I preferably
construct this air-outlet round the one from the lower floor and surmount both by
a cowl. In those cases where the hot air from the lower floor, instead of directly
being led off, is re-used for the drying on the upper floor (after having previously
been newly prepared for the drying by its intermixing with the fresh supply of
cold air, the latter, respectively in combination with a new supply of hot air, both
being introduced into the space between the two floors through those special
inlets peculiar to my system) only one air-outlet at the top of the building and of.
usual construction will be necessary. This, of course, refers only to those cases
where the whole volume of air from the lower floor is re-used.
structure.
For the purpose of better mixing and evenly distributing the air, intended for
the first drying of the green malt on the upper floor, I place a heat-distributor (or
a set of distributors) of suitable shape between the upper floor and the divisional
The management of the first stage of the drying-process (on the upper
floor) is through my invention rendered quite independent from the conducting of
the drying on the lower floor, as the ventilation and temperature on the upper
floor can be kept under perfect control, and can be raised or lowered according to
requirements, without the possibility of ever raising the temperature to such a
degree as could prove dangerous to the green malt. The whole process is thus
divided into two distinct stages, making it easily possible to first quickly evaporate
the greater part of the moisture from the green malt at a low temperature, say not
exceeding 100 degrees Fahrenheit, and afterwards finishing the drying under the
full action of the products of combustion at a high temperature, without exposing
the green malt on the upper floor to the danger of being vitrified.
Now it will be understood that the principle of my invention is to improve the
manufacture of malt by rendering the drying of the green malt on the upper floor
of double-floor-fire-kilns independent from the drying-process on the lower floor
by means of peculiar structural arrangements and by introducing through special
inlets cold air in combination with hot air (or cold air alone) into the space
between the upper and the lower floor (such air not having passed through the
malt on the lower floor), but that I do not tie myself down to any particular form
of apparatus and that I do not claim one particular mode of carrying this principle
into effect, but every other mode as well.
.
In order that the said invention may be fully understood, I shall now refer to
the several figures on the annexed sheet of drawings, representing a Forty-Quarter-
Double-floor Fire-kiln, as I preferably build it, the same letters of reference
indicating corresponding parts in all the figures.
Figure 1. is a plan through the furnaces k. k. and dunge m., the cold-air-shafts
c. c. c. c. being indicated by dotted lines.
Figure 2. is a plan through the hot-air-chamber d., indicating the cold-air-
shafts c. c. c. c. and the commencement of the hot-air-shafts w. w. w. w, the latter
in dotted lines.
Figure 3. is a plan through the lower drying-floor; showing the continuation of
the cold- and hot-air-shafts.
Figure 4. is a plan of the divisional structure a., showing the heat-distributer n.
in the shape of channels leading from the cold- and hot-air-shafts, and also showing
the vent-pipe h. from the lower floor.
Figure 5. is a plan of the upper floor, showing the continuation of the vent-
pipe h. from the lower floor.
Figure 6. is a section on the line x.-x. (Figure 1.)
Figure 7. is a section on the line Y.-Y. (Figure 1.)
The upper floor f. is divided from the lower floor e. by means of the divisional
structure a., which is built in the shape of a square roof and is made of corrugated
metal, thus, on account of its large heating-surface, effectively heating the air-
chamber b. above it and underneath the upper floor.
From the open top of this structure, and leading through the upper floor,
rises the vent-pipe h. through which the hot air, ascending from the hot-air-

page_text: chamber d. and passing through the malt on the lower floor e., is led off, this air-
outlet ending inside the air-outlet i. of the upper floor.-I make the inner outlet
shorter than the outer one, thus allowing the warmer air from the lower floor to
mix with the air from the upper floor before escaping, the exhausting action of the
former thereby assisting the upward tendency of the latter.-c. c. c. c. are the cold-
air-shafts supplying fresh cold air from the dunge m. to the upper air-chamber b.,
and w. w. w. w. are the hot-air-shafts which supply hot air from the hot-air-
chamber d. to the upper air-chamber b., all these shafts pass through the divisional
structure a. and open into the distributing-channels n., which rest upon the
divisional structure a.-'
-These distributing-channels are provided with proper
openings, through which the mixed air enters into the air-chamber.b., passes
through the upper floor f, and escapes through the outlet .o. o. o. o. are small
doors in the vent-pipe h. and they serve as discharge-holes for dropping the malt
from the upper floor to the lower one.-k. k. are the furnaces.
Green malt being very voluminous and it not being desirable to load the upper
floor deeper than can be helped, I build this floor, if possible, larger than the lower
one, which can be effected either by diminution of the upper walls or by limiting
the size of the lower floor.
The number of air-inlets (both cold and hot). I do not limit and they should all
be fitted with controlling slides.
The hot and cold-air-inlets may be combined on their way to the upper air-
chamber (for instance cold air could be introduced into the hot-air-shaft or hot air
into the cold-air-shaft) both hot and cold air in such case uniting on their way to
the upper air-chamber.
Cold air alone may be also supplied to the upper air-chamber.
As shape and size of malt-houses vary, two or more fire-places instead of one,
and two or more outlets instead of one, may be provided, also a malt-store can be
advantageously constructed in the lower part of the building round the furnace or
furnaces.
It is not my intention to restrict the application of thus dividing the kiln-
drying-process into independently from each other conducted stages to kilns with
two floors, but this system can also advantageously be applied to fire-kilns with
three floors, by either conducting the drying-process on each floor independently
from the others, in combination with a modified arrangement for heating aud
ventilating, or by only giving to the upper floor an independently conducted
supply of heat and ventilation, while the two floors underneath can be constructed
in a similar style as the two-floor-fire-kilns now in use, allowing the hot air, after
having passed through the lower floor, to pass directly through the middle one.
As there is virtually no moisture left in the malt when it is passed on to the third
and lowest floor, no harm can possibly be done to the malt on the middle floor
through the action of the hot air ascending from the lower one, nor is there any
danger of vitrifying the malt, as it has securely passed that stage on the upper
floor. Three-floor-kilns can be used to special advantage where the drying of
the particular kind of malt, to be produced, has to be finished at a very high
temperature, or where it is desired to prolong the drying-process without decreasing
the quantity of malt, to be produced within a certain time.
In Three-floor-kilns the green malt is first placed on the upper floor, is afterwards
passed on to the middle one, and the drying is finished on the lower one, the heat
from floor to floor increasing, while with Two-floor-kilns the drying begins on the
upper floor and is finished on the lower one, without any intermediate stage.
Existing kilns can be altered to my system in some suitable manner.
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 kiln-drying of malt in Two-floor-kilns in such a manner as to first partly
drying the malt on a floor which is situated above the lower floor and is divided

page_text: from the same by means of a divisional structure of suitable shape,. this upper
floor having its own peculiar independently conducted and regulated supply of
heat and ventilation, and by afterwards finishing the drying-process on the lower
floor under the full influence and in direct contact with the actual products of
combustion, as more fully described heretofore.
2. The dividing of the drying-process of malt in two-floor-kilns, where the malt
is exposed to the direct empyreumatic action of the products of combustion, into
two independently from each other conducted stages, by means of placing into
the space between the two floors a divisional structure, and by giving to the
upper floor an independent supply of heat and its own ventilation, as more fully
described.
>
3. The combination of the peculiar system of heating, ventilating, and separating
the upper floor with the drying on the lower floor under the direct action of the
products of combustion.
4. The introduction of cold and hot air, separated or combined, or of cold air
alone, into the space between the floors by means of specially constructed inlets
(such air not passing through the malt on the lower floor).
5. The divisional metal-structure a. between the two floors in its capacity as a
.medium for dividing and heating.
6. The vent-pipe h. fitted with discharge-holes o.
7. The combination of the air-outlet h. from the lower floor with the air-outlet i.
from the upper floor.
8. The application of a heat-distributor between the two floors, as more fully
described.
9. The adaption of the described system to kilns with three floors.
MAX HEDICKE.