Improvements in or relating to Apparatus for Heating Water and Generating Steam, and for Modifying the Temperature of Super- heated Steam.
Year: 1896

page_text: Date of Application, 10th Mar., 1896--Accepted, 11th Apr., 1896
COMPLETE SPECIFICATION.
Improvements in or relating to Apparatus for Heating Water and
Generating Steam, and for Modifying the Temperature of Super-
heated Steam.
I, HUGH MCPHAIL, of The Towers, Wakefield, in the County of York,
Engineer, 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 apparatus for heating water and for modifying the
temperature of superheated steam and is chiefly intended to be used in connection
with a steam generator for heating the feed water and for purifying such water by
precipitating therefrom any lime and maguesia salts that may be contained in it.
In some instances the aforesaid heater serves as an auxiliary steam generator.
In this apparatus the feed water is heated to a very high temperature in an
efficient and economical manner by the steam from the generator, and the salts of
lime and magnesia if any are present are by reason of such high temperature
precipitated and mostly collected in the bottom of the heater, whereby the formation
of scale on the internal flue tubes and shell of the generator is prevented and the
generator is thus kept internally very clean and in good condition.
My improved heater or auxiliary steam generator and purifier is in communication
with the steam and water spaces of the steam generator, and is furnished with a
number of internal tubes through which the steam (preferably superheated) from
the generator can be conveyed. By passing the steam from the generator or a
portion of it through the aforesaid tubes in the heater and purifier I accomplish
the double object of heating the feed water to a very high temperature and of
modifying or controlling the temperature of the steam before it is utilized in the
engine or elsewhere. The latter object is very important where the steam is highly
superheated.
Referring to the accompanying drawings which illustrate my invention.
Figure 1 is a vertical central section of one form of my improved heater and
purifier or auxiliary steam generator.
Figure 2 is a plan of the saine.
A is the shell of the heater and purifier and B is the inlet pipe for the cold
water, which pipe may if desired be fitted with a nozzle for spreading the water in
a shower. C is the outlet pipe for the heated water passing to the generator, the
said pipe C being preferably connected to the shell A at a point about midway
between the ends of the latter. DD are bent tubes extending through the heater
and connected at their ends to chambers or boxes E E fixed to the shell A at
opposite sides thereof. FF are branches of the main steam pipe G connecting the
latter pipe with the chambers or boxes E, E; F' F1 are stop valves in the said
branch pipes F F, and G' is a stop valve in the main steam pipe G between the
ends of the branch pipes, so that by adjusting the openings of the valves F¹ F' G¹
the whole or a portion of the steam can be passed through the pipes D in the heater
and utilized for heating the feed water to the desired temperature.
H is a pipe connecting the steam space of the generator with the upper part of
the feed water heater and purifier. It will thus be seen that the heater will have a
water space and a steam space like the generator, the water level being substantially
the same in both vessels, and that the heater will serve also as an auxiliary steam
generator. The water entering the heater through the pipe B falls in a shower
TD37

page_text: through the steam space of the heater into a conical or dished receiver J, and
thence passes through a pipe J' leading from the lower part of the said receiver to
near the bottom of the heater. In its fall through the steam space, the water will
be very rapidly heated and will be subsequently further heated by contact with
the tubes D. The high temperature obtainable in this heater ensures the
precipitation from the water of the lime and magnesia salts held in solution and
these will mainly fall to the bottom of the heater whence they can be discharged
through the blow-off pipe K. By these means the generator is kept largely free
from scale and will work longer without cleaning and be more efficient and
economical than would otherwise be the case. The internal tubes D of the heater
are largely protected from scale and deposit by the receiver J and pipe J¹ which
operate as above stated to conduct the incoming water to the bottom of the heater
where the salts are mostly precipitated before the water rises amongst the
tubes D.
The steam in the pipe G is preferably superheated steam the temperature of
which is modified or regulated by passing it through the tubes in the heater as
above described before the same is utilized. Instead of arranging the heater in a
bye-pass from the main steam pipe I sometimes connect it directly to the
superheater and pass all the steam through it.
By the aforesaid means I provide for modifying the temperature of superheated
steam by an auxiliary generator or heater instead of by the main steam generator
as described in the Specification of prior Letters Patent No. 11044* of 1892. In
some instances the connections with the main generator by the pipes H and C
are dispensed with, the apparatus then becoming an independent water heater or
steam generator.
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 I
claim is-
1. A feed water heater and purifier adapted for connection to the steam and
water spaces of a steam generator and having an inlet for water so arranged that
the incoming cold water will fall through the steam space of the heater, substantially
as and for the purpose specified.
2. A feed water heater and purifier adapted to be connected to the steam and
water spaces of a steam generator and having a series of internal steam tubes, and
an inlet for water so arranged that the water will be heated first by direct contact
with steam, and then by contact with the said tubes, substantially as described.
3. In such a feed water heater and purifier the receiver J above the heating
tubes, and the pipe J¹ leading from said receiver to near the bottom of the heater,
substantially as described, and for the purpose specified.
4. The feed water heater and purifier constructed substantially as described with
reference to the accompanying drawings.
5. Modifying or regulating the temperature of superheated steam by passing
the same through tubes in an auxiliary steam generator or feed water heater,
substantially such as that herein described.
Dated this 6th day of March 1896.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.