Improvements in or relating to the Drying and Warming of Air for Ventilation, Desiccation, or for Promoting Evaporation.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in or relating to the Drying and Warming of Air for
Ventilation, Desiccation, or for Promoting Evaporation.
I, HUBERT HIGGINS, of 4, Trinity Street, Cambridge, in the County of Cam-
bridge, Demonstrator of Anatomy to Cambridge University, do hereby declare
the nature of this invention to be as follows:-
This invention relates to the drying and warming of air for the purpose of
ventilation, desiccation, or for promoting evaporation, its object being the pro-
vision of safe and automatic apparatus for the supply of heated dry air in any
required quantity, saturated or superheated steam may be employed as the medium
for the transference of the heat.
The apparatus for carrying out the invention comprises a drying chamber, a
steam generator and superheater, and a heating shaft.
The steam generator and superheater may be of any convenient type; preferably
that portion of the generator which is exposed to the direct action of the source
of heat is bulbous in shape, and so arranged as to be capable of being discon-
nected for the purpose of cleaning and removing scale.
This bulbous portion or portions would be connected with a coil or coils (or
other arrangement of pipes giving prolonged travel to the steam), which would
serve to complete the vapourisation of the water and form the superheater. A con-
venient form would be to arrange the coils around the inside of the furnace; tho
coils may be protected from the direct action of the flames by a sheet of iron,
and the space between this and the outer wall of the furnace filled with sand or
some other convenient substance, or the coils may be partially or completely
embedded in fire-clay.
Instead of having an independent steam generator, the steam may be obtained
from any convenient source.
The steam is led from the superheater into the air heater placed at any con-
venient height in the air shaft. The heater is furnished with a number of
roughened and corrugated tubes for the passage of the air, and is connected with
a jacket formed by providing the shaft with double walls. The bottom of this
jacket is preferably connected with the water space of the steam generator so that
the steam after heating the air passes into this jacket, and as it condenses returns
automatically into the boiler.
Trays of chloride of calcium or any convénient desiccant are arranged in any
convenient receptacle to form a drying chamber for the air. Preferably two of
these are provided and used alternately so that when one becomes inefficient
through the amount of moisture absorbed from the air it may be cut out of the
circuit and dried for instance by superheated steam from the superheater without
interrupting the process.
Desirably the air is first passed through a rough filter of, for instance, cotton

page_text: The steam is led from the superheater into the air-heater placed at any con-
venient position in the air shaft. The heater consists of one or more roughened and
corrugated tubes for the passage of the air, and may be connected with a jacket
formed by providing the air shaft with double walls. The bottom of this jacket
or of the steam tube or tubes is preferably connected with the water space of the
steam generator so that the steam after heating the air passes into this jacket, and
as it condenses returns automatically into the boiler.
Trays of chloride of calcium or any convenient desiccant may be arranged in
any convenient receptacle to form a drying chamber for the air, or a certain por-
tion of the air, before it is heated by the steam. Preferably two of these chambers
are provided and used alternately, so that when one becomes inefficient through the
amount of moisture absorbed from the air it may be cut out of the circuit, and
dried, for instance by superheated steam from the superheater, without interrupt-
ing the process.
In some cases, for instance, when the air is used for ventilating purposes, it
is preferable not to thoroughly dry the air. In such cases the calcium chloride
may be dispensed with.
For certain purposes, as, for instance, when used for the ventilation of living
rooms in large towns, in which it is liable to be contaminated, the air may be first
passed through a rough filter of, for instance, cotton wool or tow; it is then passed
over the trays of chloride of calcium, thence into the bottom of the warming shaft
and through the tubes of the heater, being delivered at the top of the shaft and
distributed in the manner best suited to the purpose for which it is required.
After being dried and before entering the shaft, the air may be warmed by
passing it round the outside of the generator furnace.
Any necessary doors, inspection holes, valves, fans and other fittings may be
provided. The air shaft may be lagged or it may be placed wholly or partly with-
in the walls of the chimney of the generator or other furnace.
When it is desired to maintain a chamber, such for instance as an incubator,
or a chamber for the desiccation of organic material at temperatures below
say 80° C. it may be convenient to employ instead of water, a liquid having a
lower boiling point. In this case it would be advisable to use gas or some other
readily controlled source of heat such as steam for generating the vapour, and to
employ a closed circuit for the conveyance and distribution of heat, that is to
say, the heat causes the vapourisation of the liquid of low boiling point used, it
then parts with its heat in warming air and returns as a liquid to the source of
heat.
Preferably the apparatus is worked by steam at approximately atmospheric pres-
sure, rendering the system an absolutely safe one. Its action is continuous and
automatic, a great advantage in all desiccating and ventilating operations.
The accompanying drawings illustrate diagrammatically two typical forms of
apparatus constructed according to this invention.
Figure 1 is a side view of an air shaft and heater with drying chamber and
filter:
Figure 2 is a plan on a larger scale of the drying chamber, and,
Figure 3 is a side view of an air shaft and heating tube placed in a chimney
shaft and connected with a steam generator.
Like letters indicate like parts in all figures.
Referring first to Figure 1, A is an air shaft having a jacket A¹ and provided at
Its upper portion with a pipe A2-by which the heated air can be distributed to
the drying chamber, if used for desiccating purposes, or to the various rooms of
building if required for warming and ventilating purposes--and at its lower
portion with a hood A by which it is connected with the air supply pipe A*.
Within the air shaft A is placed the heating chamber B. As shown in the draw-
ng this is formed integral with the air shaft, comprising two tube plates B1 B2,
ixed on the inner walls of the air shaft and occupying its whole area, the plates
being connected together by roughened or corrugated tubes B³, through which
he air circulates. The heating chamber is provided with a steam supply pipe B*,

page_text: Having now particularly described and ascertained the nature of this said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. In air warming apparatus the combination with an air shaft of a tubular
warming chamber and a jacket substantially as described.
2. In air warming apparatus the combination with an air shaft of a drying
chamber substantially as described.
3. In air warming apparatus the combination with an air shaft of a vapour
generator with or without a superheater and a warming chamber forming a closed
circuit with the generator substantially as described.
4. The employment for warming air of a fluid having a lower boiling point
than water substantially as described.
5. The apparatus for drying and warming air substantially as described or as
illustrated in Figures 1 and 2 or in Figure 3 of the accompanying drawings.
D
قيم
1
P
ت
1000
HUBERT HIGGINS.
Boult & Wade,
Agents for the Applicant.
HUBERT HIGGINS.
Boult & Wade,
Agents for the Applicant.