Improvements relating to the Purifying and Refining of Iron, and Apparatus therefor.
Year: 1896

page_text: Date of Application, 28th Apr., 1896-Accepted, 30th May, 1896
COMPLETE SPECIFICATION.
[Communicated from abroad by HAWKINS STEEL COMPANY (LIMITED), of
141 Woodward Avenue, Detroit, Michigan, United States of America.]
Improvements relating to the Purifying and Refining of Iron, and
Apparatus therefor.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45 Southampton Buildings, in the County of Middlesex, 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 invention relates to a process and apparatus for purifying and refining iron
and producing thereby the homogeneous metal having the properties of steel.
The process broadly described consists in conducting the molten metal as
obtained from melting in a cupola, or as obtained directly from the blast furnace,
into a reverberatory flame chamber and subjecting it therein in a divided state
to the action of concentrated jets or currents formed of super-heated steam, air
and the highly heated carbonaceous products of combustior, then thoroughly
eliminating the impurities and decarbonizing the metal by puddling the molten
mass in a reverberating chamber to a point less than balling, all as more fully
hereinafter described in connection with the drawings, in which
Fig. 1 is a longitudinal section on line a Fig. 2, through an apparatus designed
to carry out the invention, and
Fig. 2 is a cross section thereof on line y y Fig. 1.
A represents a cupola (or furnace suitably organized for making cast iron); B is
the tap; C is a lead or discharge pipe; D is a hot well into which the molten iron
from the cupola or furnace is discharged; E is a contracted discharge spout from
the bottom of the well, arranged to discharge the molten metal in a spray or thio
sheet. F is a reverberatory chamber intervening between the bridge and the
hearth of a puddling furnace and forming a down-take for the products of
combustion on their way from the furnace G to the puddling chamber H and so
arranged as to concentrate the heat as much as possible upon the molten stream of
iron discharged into it from the spout.
II are puddling holes; 1' is a slag. door; J is the furnace tap, K is a boiler
for furnishing steam, L is a supplementary oil burner or other source of heat-for
the boiler.
M is a coil of steam pipes suitably located in the walls of the furnace to superheat
the steam from the boiler. N is a steam head in the bridge wall and provided with
one or more jets N' for discharging superheated steam into the reverberatory
chamber F, and O is a like head above the chamber and provided with one or more
jets O¹ for injecting air into the chamber F.
The furnace G is provided with a suitable feed door R and with suitable air
feeding devices as S to promote active combustion of the fuel in the furnace.
Preferably means for introducing superheated steam are also provided as
shown at St.
In practice the parts being arranged as shown and described, the operation is as
follows: Molten iron of a desirable low percentage of carbon being produced from
the furnace or cupola A and discharged therefrom into the well D it is allowed to
drip therefrom through the spout E into the reverberatory chamber F.
Here the sheet or spray of molten metal passes directly across the path of the
flaming products of combustion and by the reverberatory action of the chamber F

page_text: its temperature is raised to and maintained at a white heat while simultaneously
therewith a concentrated current or jet of air and superheated steam is directed
upon it.
The molten metal after being subjected to this action collects on the hearth of
the puddling chamber H and there it is worked (preferably using oak saplings) in
such a manner as to remove all the slag and secure thorough puddling to a point
less than balling and until the desired condition of the metal is realized, which may
be determined by removing test spigots at intervals.
The concentrated jets of steam and air decarbonize the metal and act upon the
various impurities in a manner to permit their subsequent elimination in the form
of slag, thereby leaving a homogeneous product which is admirably adapted for
producing articles for which steel is or may he adapted, and which may be obtained
with any desired percentage from the chemically pure metal to the percentage in
steel having the maximum chemical combination with carbon.
The difficulty in purifying and refining iron by similar processes heretofore has
always proved a failure, mainly on account of the difficulty of preventing the
metal from becoming chilled and thus limiting the refining action to certain
impurities only.
In this process the metal is raised to a white heat and maintained so by letting
it enter the chamber F at the hottest part and fall like a thin curtain across the
path of the flaming gases so that while it is exposed on one side to the oxidizing
action of air and steam, it is exposed on the reverse side to the full reverberatory
heat of the furnace and it will continue to boil while being worked in the puddling
chamber as the entire length of it is filled with gaseous products in the state of
combustion.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondents, I declare that what I claim is:
1. The herein described process for purifying and refining iron which consists in
conducting the molten metal in a thin sheet into a reverberatory chamber in which
it is exposed to the products of combustion from a furnace in a manner to heat the
metal and maintain the same at a white heat, in subjecting it therein to the action
of a concentrated current of superheated steam and air and then thoroughly
eliminating the impurities and decarbonizing the metal by puddling the molten mass
to a point less than balling.
2. In an apparatus for purifying and refining iron, the combination with a cupola
or furnace, of a puddling furnace provided with the reverberatory heating
chamber Fi intermediate between the bridge wall and the hearth of the puddling
chamber, and into which the heated products of combustion pass, the hot well D
having a discharge spout E. into the reverberatory chamber' and communicating
with the furnace, or cupola and the steam and air tuyeres J, O for producing a
concentrated current of superheated steam and air.
Dated this 28th day of April 1996.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.