Valuable Products thereirom.
Year: 1886

page_text: Date of Application, 12th Oct., 1886
Complete Left, 10th Aug., 1887
Complete Accepted, 7th Oct., 1887.
Valuable Products thereirom.
We, JOHN COPE BUTTERFIELD of Westbury, Barking, Essex, and 7 Westminster
Chambers, Victoria Street, London, Analytical Chemist and HUGH HERBERT MASON
of Abbey Lodge, Barking, Essex, Surgeon, do hereby declare the nature of this
invention to be as follows:-
The object of this invention is the treatment of sewage in its different forms and
either wet or dry. In the case of dry sewage such as that from dry earth closets, it
is taken direct and in the case of wet sewage the cakes from the filter presses or
the sewage after it has been solidified by some other means and heated in a vessel
from which air is excluded. This vessel or retort is fitted with an exit pipe which
communicates with a condensing apparatus in which the oil gas ammonia water &c.
are condensed by artificial or air cooling. The oil and ammonia water are separated
from each other by their densities in a separator or vessel preferably of cast iron and
provided with suitable pipes for the eduction of the products.
Each of these products is then treated in a suitable manner for the production from
the ammonia, water of amnionia, or its salts, and from the oily distillate of burning
and lubricating oils.
The residue remaining in the retort and consisting of the mineral and carbonaceous
matter has a commercial value for the purification of sugar or of sewage; in the
former case by reason of its de-colorizing action, and in the latter by causing the
precipitation of the solid matter in sewage as delivered from the ordinary conduit.
This calcined residue would contain after one calcination a variable small amount
of phosphoric acid which could be increased by use and re-use of the first product,
and in this way a product could easily be obtained in which the proportion of
phosphoric acid would be sufficiently high for the purposes of artificial phosphatic
manure.
Lime either naturally present in the sewage or added may be used.
In some cases alumina is present in the ash; this may be recovered in the
ordinary manner.
1000

page_text: COMPLETE SPECIFICATION.
Improvements in the Treatment of Sewage and the Recovery of
Valuable Products therefrom.
We, JOHN COPE BUTTERFIELD of Westbury, Barking, Essex, and 7 Westminster
Chambers, Victoria Street, London, Analytical Chemist, and HUGH HERBERT MASON
of Abbey Lodge, Barking, Essex. Surgeon, 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 relates to the destructive distillation of dried sewage, or sewage
sludge or other forms of animal excreta and the recovery therefrom of valuable
products such as illuminating heating and lubricating oils known as paraffine oils and
ammonia water.
Before commencing the distillation the sewage must be reduced to a dry state
without subjecting it to sufficient heat to produce ammonia or to drive off any present
therein. In places where the excreta is collected on any of the so-called dry systems,
it should be reduced into a condition of either cake or powder by any convenient
means of drying.
The sludge obtained from the tanks where the sewage is water-carried should be
treated by any of the well known methods as filter-pressing to obtain it in the
condition described above. When thus prepared the sewage is subjected to the action
of heat in a suitable vessel or retort and the products of distillation condensed and
separated, the
processes being fully described in connection with the accompanying
drawings which illustrate apparatus suitable for the purpose. Fig. 1 represents a
vertical section of the retort. Figs. 2 and 3 represent vertical sections of the
condensing and separating vessels.
The retort which is of ordinary construction consists of a central tube H of cast
iron surrounded by brickwork with flues for the passage of the heated gases arising
from the fuel. The bottom of the retort which is open dips into a trough B containing
water, and it is provided at the top with a feed hopper C which is closed by a conical
plug D hinged to a lever E carrying a weight F at one end to counterbalance the
weight of the plug which when in place is secured by means of the clip G. The
material is conveyed to the mouth of the retort in trollies which run on a railed
platform H and a sufficient quantity is emptied therein to fill the retort nearly to the
level of the eduction tube J. The retort is then heated until the lower portion thereof
arrives at a dull red heat at which it is kept so long as the operation continues. At
intervals of about an hour a portion of the spent material is withdrawn from the iron
trough B and a corresponding quantity of fresh material added at the top so as to
preserve the same level and insure a regular and continuous yield throughout. We
find that the yield and quality of the oil is improved by injecting steam into the
retort by means of the pipe K. The gases and vapours evolved in the retort are
carried off by the pipe J which is provided with a manhole at J¹ so that it may readily

page_text: be cleaned out. From the pipe J the gases and vapours pass through a condensing
coil L preferably of iron or lead which is placed in a tank L' which is kept full of
water constantly renewed, cold water entering through the bottom at the inlet tap L'
and leaving the tank by the outlet L³. In passing through the condenser the
condensible products are reduced to a liquid state in which condition they pass into
the separator Fig. 3 consisting of a closed cast iron or other vessel M through the
cover M' of which the end of the coil L passes. The liquid products of the distillation
are allowed to remain in the separator until they separate through gravitation, after
which the lighter products or oils may be drawn off through a tap N to undergo
further separation according to well known processes, while the heavier watery
products may be drawn off by a tap N' situated at the bottom of the vessel, and the
ammonia or its salts recovered in the usual manner.
When the process of distillation is carried on continuously a series of separators
may be used in conjunction with one condenser, the end of the coil L being constructed
so as to be readily disconnected without allowing the products to escape. By this
process the gases will be deprived of all condensible or soluble matter likely to be of
value and the gases themselves which pass on through the pipe M² may either be
allowed to escape or conducted back to the furnace.
The temperature inside the retort should not be below 600 degrees Fahrenheit nor
above 900 degrees Fahrenheit.
A larger amount of ammonia is given off if the material be roughly mixed with
about 3 per cent. of slaked lime.
The process can be conveniently carried into effect by means of the above described
apparatus but any form of retort may be used which will heat the material to the
required temperature such as the patented retorts of Youngs and Reilby, or Oswald
Rose and other patterns of condenser and separator may be employed such being
in common use.
Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed we declare that what we claim is
1. The production of paraffine oils from sewage by destructive distillation at a
temperature between 600° Fahrenheit and 900° Fahrenheit.
2. The production of paraffine oils and ammonia water from sewage by destructive
distillation at a temperature between 600° Fahrenheit and 900° Fahrenheit.
3. The destructive distillation of dried sewage mixed with about 3 per cent of lime
for the purpose of obtaining paraffine oils and ammonia water.
Dated this 2nd day of August 1887.
J. C. BUTTERFIELD.
HUGH H. MASON.