Improvements in the Method of Utilizing Garbage and other Waste Products.
Year: 1894

page_text: Date of Application, 4th Dec., 1894-Accepted, 5th Jan., 1895
COMPLETE SPECIFICATION.
Improvements in the Method of Utilizing Garbage and other
Waste Products.
I, NATHANIEL BARRETT PowTER, of 104 West 61st Street, in the City and
State of New York, United States of America, Gentleman, 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 object of my invention is to provide a quick and economical method of
utilizing the valuable elements contained in such substances as slaughter house
refuse, fish refuse, city garbage and refuse from bone boiling establishments and
other substances, which, by reason of their containing organic animal or vegetable
matter in a state of partial decay, have to be treated rapidly and under conditions,
which shall not be deleterious to the public health.
My improved process consists in first subjecting the substance to be treated to a
boiling or steaming process until the matter becomes reduced to a consistency
known as sludge or slush. It is sometimes advisable to ad l a little sulphuric acid
to the mass, while undergoing this boiling or steaming process. After the
matter has assumed the condition of sludge, the grease should be removed by
skimming or other convenient method, clarified and sold. The second step of
the process consists in thoroughly mixing with this sludge a proper amount of
natural phosphate of lime, alumina phosphate or other phosphate containing
insoluble phosphoric acid. The amount of phosphate required varies from five
per cent. upwards, according to the character of the substances composing the
sludge; but about fifteen per cent. of phosphate will in most cases answer the
purpose. The mixture is then evaporated to dryness in a vacuum, being constantly
agitated or stirred during the evaporation to prevent solidifying. After this
simultaneous stirring and evaporating in the vacuum has continued for about
three hours, the mass will become dry and granular, bearing somewhat the
appearance of coarse, brown sugar when the vacuum is broken by the admission
of air; and the batch of material treated can be easily removed by shovels or
scoops and put into boxes, bags or barrels, as desired, and shipped for use as a
fertilizer, the valuable properties of the organic matter treated and of the
phosphate being retained in the granular mass and being readily soluble and set
free, when applied to the fields, in the usual manner of fertilizers.
A convenient form of apparatus is shown in the accompanying drawing and
consists of a horizontal tank of cylindrical form A partially surrounded by a
steam jacket B. The tank is provided with a manhole a-a for inserting the
various ingredients with the discharge openings b-b-b for removing the finished
product, the exhaust c connected with a vacuum pipe not shown, by which a
vacuum in the tank is created, if desired. It is also provided with a central
longitudinal shaft d carrying stirring arms not shown, in the interior of the tank.
Inlet pipes e admit steam to the interior of the tank and taps or inlets f--f
admit steam to the steam jacket or exhaust the same, as desired.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what 1
claim is:
1. The above described method of utilizing garbage and other waste products,
which consists· First in reducing the same to a condition of sludge by steaming or

page_text: boiling, in the presence of sulphuric acid, and removing the grease therefrom;
second, mixing the sludge with a proper amount of insoluble alumina phosphate;
and lastly, subjecting the same to a simultaneous stirring and evaporation in
vacuum, until the same is converted into a dry, granular mass, substantially as
described and for the purposes specified.
2. The above described method of utilizing garbage and other waste products,
which consists: First, in reducing the same to a condition of sludge by steaming or
boiling and removing the grease therefrom; second, mixing the sludge with
insoluble alumina phosphate; and lastly, subjecting the same to a simultaneous
stirring and evaporation in vacuum, until the same is converted into a dry, granular
mass, substantially as described and for the purposes specified.
3. The above described method of utilizing garbage and other waste products,
which consists: First, in reducing the same to a condition of sludge by steaming or
boiling, in the presence of sulphuric acid, and removing the grease therefrom;
second, mixing the sludge with a proper amount of phosphate of lime or other suitable
phosphate; and lastly, subjecting the same to a simultaneous stirring and evaporating
in vacuum, until the same is converted into a dry, granular mass, substantially as
described and for the purposes specified.
4. The above described method of utilizing garbage and other waste products,
which consists: First, in reducing the same to a condition of sludge by steaming or
boiling, and removing the grease therefrom; second, mixing the sludge with
phosphate of lime or other suitable phosphate; and lastly, subjecting the same to
a simultaneous stirring and evaporating in vacuum, until the same is converted
into a dry, granular mass, substantially as described and for the purposes
specified.
Dated this 8th day of November 1894
NATHANIEL BARRETT POWTER.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.