Improvements relating to the Distillation of Substances Containing Nitrogen, and Apparatus therefor.
Year: 1884

page_text: Improvements relating to the Distillation of Substances
Containing Nitrogen, and Apparatus therefor.
PROVISIONAL SPECIFICATION.
I, WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings, in the County of Middlesex do hereby declare the nature
of my invention for "IMPROVEMENTS RELATING TO THE DISTILLATION OF SUB-
STANCES CONTAINING NITROGEN, AND APPARATUS THEREFOR to be as follows:-
"
This invention relates to an improved method of, and apparatus for, distilling
urine and other solid or liquid substances containing azotized matter.
The said apparatus comprises a furnace with one or more retorts heated through
the medium of a single hearth. The retorts employed cause the substance under
treatment to enter one or more circulating passages by means of ribs arranged upon
their bottoms. These retorts can be made of any suitable material such as cast or
wrought iron, or earthenware.
Each of the said retorts is provided with one or two heads carrying doors for
cleaning purposes, and three pipes, the first of which serves as the inlet for the
substance to be treated, the second for the introduction of lime or of other suitable
re-agent, and the third as the outlet for the neutral liquids. Each head is divided
vertically by a partition which forms a joint with the rib of the retort.
The operation of the apparatus is as follows, that is to say:-The substance to
be treated is conveyed by means of a pump into a tank, from which it passes suc-
cessively through a pipe, a regulating cock, a scrubber or cooling apparatus, and
through the inlet pipe. It thus arrives in the retort where it circulates in thin
sheets and then leaves through the outlet pipe which conducts it to a tub or other
receptacle When the said tub or receptacle is filled, the liquid is discharged into
a drain, or otherwise disposed of.
The lime-milk or other re-agent, contained in a vessel supported above the retort,
enters the same through a tube or pipe and is thus brought into contact with the
substance to be treated either in the head of the retort or in the outlet pipe.
In its passage through the retort, the substance under treatment is heated to
boiling point, and gives up the carbonate of ammonia which it held in solution, and
the more fixed salts are liberated when, on issuing from the retort or in the outlet
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page_text: pipe, they are brought in contact with the lime. The liquid flowing into the said
tub or receptacle is, therefore, absolutely neutral. The gases and steam, being
incapable of breaking the hydraulic joint of the said tub or receptacle, are com-
pelled to pass by the same path as the liquid, but in the contrary direction. They
escape through the inlet tube or pipe, into the lower portion of the scrubber or
cooling apparatus and pass through a series of wire-gauze diaphragms, and through
a lead pipe, to a tank or vessel in which they are brought in contact with sulphuric
acid.
During this passage of the gases and vapor, the substance under treatment con-
denses the steam, and the sal-ammoniac and carbonate of ammonia arrive in an
almost dry state in the sulphuric acid.
In order to prevent the crystallization of the carbonate of ammonia in the said
lead pipe, sulphuric acid contained in another vessel is allowed to pass, drop by
drop, through a pipe into the said lead pipe.
When the operation is terminated and the sulphuric acid of the said tank or
vessel is converted into sulphate of ammonia in a pasty state, this sulphate is
removed by means of a wooden scoop and thrown upon a strainer. The straining
being completed, the salt is drawn or pushed on to the top of the furnace, which is
arranged for drying purposes, and thence the salt is placed in casks.
As soon as the-salt-is-removed from the said tank or vessel, it is replaced by a
fresh quantity of sulphuric acid and the operation recommïences.
The same furnace can be used in the manufacture of all the ammoniacal products.;
but in the manufacture of volatile alkali, the mixture of the lime must be effected
in a suitable tank in order to avoid the liberation of the carbonate of ammonia, and
to effect a complete conversion of the ammoniacal salts and salts of lime.

page_text: "
Agents, Southampton Buildings, in the County of Middlesex do hereby declare
the nature of my invention for "IMPROVEMENTS RELATING TO THE DISTILLATION
OF SUBSTANCES CONTAINING NITROGEN AND APPARATUS THEREFOR and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
This invention relates to the treatment of azotized liquids especially the waters
of gas-works and the liquid portion of night-soil; and to apparatus therefor.
In the accompanying drawing,
Figure 1 shows the general arrangement of apparatus for continuously treating
azotized liquids.
Figure 2 is a sectional view of a portion of the apparatus.
Figure 3 is a sectional view of a detail hereinafter referred to.
The said apparatus as shown in the drawing comprises a furnace A having a return
flue A¹ for the products of combustion; a divided retort B, a heater D placed above
the retort; a reservoir L, and the necessary pipes and tubes for connecting the
various parts of the apparatus.
The retort B is connected with the heater by means of the pipe G and the
tubo F. The tube F is connected with a perforated pipe F¹ which passes through
the heater D as represented in Figure 2. The outer end of the retort is provided
with a discharge pipe H which establishes communication between the retort and
a reservoir I.
Figure 2 shows a rib or partition B' which runs longitudinally of the retort and
enables a double circulation of the liquid in the same.
This apparatus can be arranged in two different manners to produce either
sulphate of ammonia or volatile alkali. The description of the operation will enable
both arrangements to be understood.
For the production of sulphate of ammonia the reservoir L is filled by means of
the pump K with the liquid to be treated, which flows into the heater D through
the pipe M. When the heater is filled to the hoight of the orifice of the pipe G
the liquid flows into the retort B, the cock R enabling this feed to be regulated.
The fire in the furnace is now lighted, when the evolution of volatile vapours
commences. These vapours escape through the pipe F and are condensed by the
liquid in the heater D and consequently enrich it. When the temperature is
sufficiently high for causing the ebullition of the liquid, the continuous operation
of the apparatus commences, the flow of the liquid being regulated by opening the
cock R more or less. The volatile vapours passing through the tube F, traverse
the heater and act upon the liquid therein, which they maintain in a state of
ebullition subsequently escaping through the pipes O, O¹, the cock R¹ of which is
open. The pipe O' enters a vessel containing sulphuric acid, in which vessel the.
conversion into sulphate of ammonia takes place.

page_text: Besides volatile salts, the evolution of which is effected by ebullition, there exist
fixed salts which are not carried away and which nevertheless require to be
treated. For this purpose a receptacle H³, a section of which is shown in Figure 3,
is placed upon the pipe H connecting the retort B with the reservoir L This
receptacle is filled with quick lime. The waters leaving the retort pass in contact
with this lime whereby the fixed salts are decomposed and ammoniacal gas is
liberated. As this ammoniacal gas cannot pass through the hydraulic joint formed
by the liquid in the receptacle I, it ascends into the heater and follows the course
above described. All the liquids flowing out at J from the reservoir I are neutral
and can be conducted away.
If the apparatus is to produce volatile alkali, the general operation remains the
same, but it is necessary to use lime. The employment of this material however
necessitates some small alterations which I will proceed to describe.
As in the preceding case, prior to setting the apparatus in operation, the heater D
is filled with aminoniacal water by means of the cock R. Through apertures
formed in the upper part of the dome E of the heater and covered by discs E¹
Figure 2 or through a tube N, Figure 1, milk of lime is poured into a cylindrical
receptacle placed in this dome to the level of a concentric tube El which serves as
an overflow through which the milk of lime enters the heater. This tube E¹¹ is
placed around the feed pipe-M-above the pipo F1 in such a manner that the milk
of lime is well mixed with the liquid in the heater. The fire-in-the furnace is now
lighted and the admission cock R is regulated as for the manufacture of sulphate
of ammonia. The cock R' is closed and the cock R" is opened for the passage of
the ammoniacal gas.
--The milk of lime mixed with the ammoniacal liquid owing to the motion caused
by the passage of gas through-the--perforations in the pipe F¹, transforms the
ammonical salts contained in the said liquid into salts of lime, and-liberates. the_
ammonia in the form of ammoniacal gas. This ammoniacal gas, in order to find an
exit, follows the passage-indicated by the arrows, Figure 2, and traverses the
annular receptacle in the dome, undergoing a second-treatment with milk of lime,
the object of which treatment is to decompose the ammoniacal salts which have
not been decomposed in the heater. The gas thence passes into a coil, Figure 1,
cooled by the liquids to be treated. In this coil the water vapour is condensed, the
gas being led into a purifier containing charcoal which removes from it the last
traces of moisture and of hydrocarburets which it may contain. The gas thence
passes into the purifiers Y where the last traces of impurities are removed, and
thence into a leaden vessel Z where it is condensed. The vessel Z is surrounded
by cold water. From the condenser Z the ammonia is collected in suitable bottles.
The construction of the apparatus described may be modified without departing
from the nature of this invention. ⚫
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent, I declare that what I claim is
First: The employment of a retort provided with one or more ribs or partitions
for causing a double or multiple circulation of the liquid to be treated.
Second: The continuous treatment of azotized liquids by means of suitable
apparatus for the purposes specified.