Improvements in Steam Generators or Apparatus in connection therewith for Purifying Feed Water.
Year: 1889

page_text: Date of Application, 8th Mar., 1889.
Complete Specification Left, 7th Dec., 1889-Accepted, 11th Jan., 1890
PROVIDIONAL SPECIFICATION.
Improvements in Steam Generators or Apparatus in connection
therewith for Purifying Feed Water.
1, JOHN DONALDSON of Church Wharf, Chiswick, in the County of Middlesex,
a Member of the firm of John I. Thornycroft & Co., Steam Yacht and Launch
Builders, do hereby declare the nature of this invention to be as follows:-
-
This invention has for object. the removal from the feed-water supplied to
steam generators of impurities, such as certain compounds of lime and magnesia
usually contained therein and which cause incrustation of the generator.
It is well known that if water containing certain salts in solution, such. for
example as some salts of lime and magnesia, be heated to a high temperature
by mixture with steam or with steam and hot water, such salts or the bases
thereof will be rendered insoluble and will be deposited.
According to this invention I heat the feed water by intimately mixing it
with jets of steam or steam and hot water and project the mixture upon a baffle
plate or plates over which the water and impurities then rendered insoluble
and held in suspension are caused to flow into a suitable vessel or chamber
wherein the impurities are allowed to deposit and from which they may be
withdrawn from time to time. To facilitate the deposition of the solid impuri- .
ties, I may employ a removable box or receptacle, provided with one or more
partitions or baffle plates and through which the water containing the impurities
is caused to flow. Or the vessel or chamber itself, in which the impurities are
allowed to deposit, may be provided with plates or divisions arranged to serve
after the manner of baffle plates to assist deposition. Such plates or divisions
may in some cases be the blocks or plates of zinc sometimes used in steam
generators to prevent corrosion thereof.
By projecting the feed water and steam upon a baffle plate or plates, the
impurities rendered insoluble by heat, are washed into the depositing vessel,
and the plate or plates thus kept free from incrustation.
The method of purifying feed water herein described may advantageously be
employed in a steam generator of the type described and shewn in the Specifi-
cation of Letters Patent granted to John Isaac Thornycroft dated 31st Jan.
1885 No. 1404. In this case the feed water is discharged upon the top of the
baffle plate and is intimately mixed with the jets of steam and water discharged
from the upper ends of the series of tubes connecting the lower water chambers
or vessels with the steam collector and separator. The heated feed water flows
over the baffle plate in a highly heated state into the lower part of the steam
collector and separator whence it flows by a return tube or tubes to the lower
water chambers or vessels in the bottoms of which the solid impurities are
allowed to deposit; removable boxes or receptacles may in some cases be placed
in the said chambers or vessels as herein before mentioned to receive the deposit
their ends being constructed to admit of the ready removal of the boxes or
receptacles, or the withdrawal of the insoluble impurities deposited..
Dated this 8th day of March 1889.

page_text: COMPLETE SPECIFICATION.
Improvements in Steam Generators or Apparatus in connection
therewith for Purifying Feed Water.
I, JOHN DONALDSON, of Church Wharf, Chiswick, in the County of Middlesex,
a member of the firm of John I. Thornycroft & Co., Steam Yacht and Launch
Builders, 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 has for object the removal from the feed-water supplied to
steam generators of impurities such as certain compounds of lime and magnesia
usually contained therein and which cause incrustation of the generator.
It is well known that if water containing certain salts in solution, such for
example as some salts of lime and magnesia, be heated to a high temperature
by mixture with steam or with steam and hot water such salts or the bases
thereof will be rendered insoluble and will be deposited.
'
According to this invention I heat the feed water by intimately mixing it
with jets of steam or steam and hot water and project the mixture upon a baffle
plate or plates over which the water and impurities then rendered insoluble
and held in suspension, are caused to flow into a suitable vessel or chamber
wherein the impurities are allowed to deposit and from which they may be
withdrawn from time to time. To facilitate the deposition of the solid impuri-
ties may employ a removable box or receptacle provided with one or more
partitions or baffle plates and through which the water containing the impurities
is caused to flow. Or the vessel or chamber itself, in which the impurities are
allowed to deposit, may be provided with plates or divisions arranged to serve
after the manner of baffle plates to assist deposition. Such plates or divisions
may in some cases be the blocks or plates of zinc sometimes used in steam
generators to prevent corrosion thereof. By projecting the feed water and
steam upon a baffle plate or plates, the impurities rendered insoluble by heat,
are washed into the depositing vessel, and the plate or plates thus kept free
from incrustation.
In the accompanying drawings,
Fig. 1 shews, partly in transverse section, and partly in end elevation; and
Fig. 2 partly in longitudinal vertical section and partly in side elevation,
portions of a tubulous steam generator with my invention applied to it.
In the example shewn, the steam generator is of the type described and
claimed in the Specification of Letters Patent granted to John Isaac Thorny-
croft dated 31st January 1885, No. 1404.
-1 is a horizontal cylindrical steam collector and separator, and 2 is a baffle
plate, of curved form in transverse section arranged longitudinally therein.
3 is a steam outlet pipe arranged below the baffle plate 2. 4, 4 are inlet pipes
for supplying the feed water to be purified. Their outlet ends are so arranged
as to discharge the feed water upon the top of the baffle plate 2, which may
bo grooved or made of concave form along its crown or upper part as shewn.
5, 5 are valves for controlling the supply of feed water. 6 is a water vessel
of which there may be two, one situate at each side of the fire grate. 7, 7 are
tubes, of which in this particular construction of steam generator there are a
number, arranged in groups at each side of the fire grate, as described in the
said former specification herein before mentioned, their lower ends being secured
to the water vessels 6 and their upper ends to the upper part of the steam
collector and separator 1. These upper ends of the tubes are so arranged that
when the steam generator is at work jets of steam or mixed water and steam
are projected therefrom upon the top of the baffle plate the water falling to the
lower part of the steam collector and separator whilst the steam passes under

page_text: the baffle plate and enters the steam pipe. 8, 8 are return tubes connecting the
lower part of the steam collector and separator 1 with the water vessels 6, one
only of which is shewn in the drawings. 9, 9 are the ordinary blocks or plates
of zinc arranged within each water vessel 6 and serving in conjunction with a
zinc rod 9 carried thereby and connected with the shell of the vessels 6 to
prevent corrosion of the apparatus. With the construction described, when the
feed water is turned on whilst the steam generator is under steam, the water
will be directed by the inlet pipes 4 upon the baffle plate where it will be
intimately mixed with, and heated to a high temperature by the steam or steam
and water that will also be discharged upon the baffle plate from the tubes 7. The
feed water and its impurities thus rendered insoluble, will flow over the baffle
plate to the bottom of the steam collector and separator 1 and thence by the
return tubes 8 to the water vessels 6 wherein the impurities will deposit and
from which they may be blown off from time to time through a blow off
pipe 10 and cock 11. The deposition of the solid impurities will be facilitated
by the zinc plates or blocks ŷ which will act as battle plates. Or in lieu of,
or in addition to the blocks or plates 9 there may be used a removable box 12
shewn in dotted lines in Fig. 2, into which the water and impurities will descend.
When this removable box is employed, the pipe 10 may be dispensed with or be
arranged further inward and beyond the box. The construction of this box
with an inlet opening at 12" and an outlet at 12 is such that solid impurities
will deposit and remain in the box but water will pass out by the opening 12b.
The part 13 of the box serves as a baffle plate. The ends of the water vessels 6
should in this case be arranged to be readily taken off, to admit of the ready
removal of the box and contained impurities. The purified water passes from
the vessels to the tubes 7 wherein it is wholly or partly converted into steam
As will be obvious, the vessel 1 with baffle plate 2, inlets for water to be
purified and for steam to act upon such water, and outlets for the water treated
and for the steam may be constructed in various forms and instead of forming
a part of a steam generator may form independent water purifying apparatus
that receives steam from any convenient source through fubes corresponding
to the tubes 7 and discharges the purified feed water either to a feed tank or
direct to a steam generator.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that
what I claim is;-
1. For purifying feed water, the combination of a baffle plate, a feed water
inlet or inlets arranged to discharge feed water above such battle plate, an inlet
or inlets for steam (or steam and hot water) to act upon the feed water above
the battle plate, these several parts being arranged in a suitable vessel connected
with a second vessel through which the feed water that has been acted upon as
aforesaid can pass and wherein any impurities rendered insoluble by the action
of the steam or steam and hot water can deposit substantially as herein described
for the purpose specified.
2. In a steam generator of the kind hereinabove referred to, admitting the
feed water above the baffle plate in such a manner as to cause it to be there
acted upon and purified by the entering jets or streams of steam or steam and
hot water as set forth.
Dated this 7th day of December 1889.
W. Lloyd Wise,
JOHN. DONALDSON.
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.