Evening star., 1937-11-14
Robot System Regulates Temperature for
$40 Acres Of Floor Space With
$4,000 Feet of Pipe.

its destination, where it does its duty
of warming the radiators in hundreds
of rooms. This duty done, 1t starts
back to the Central Heating Plant,
this time in the form of water.
THERE are two prime reasons, from
an economical standpoint, for saw
ing all the water possible and using it
over again. One is the saving in cost
of treatment, by retrieving and reusing
a certain amount of the already treat
ed water; the other is economy in the
use of coal, as the returning water
usually retains a certain amount Of
heat.
Needless to say, not all of the water
originally used to generate the steam
returns to the heating plant. but en-
gineers estimate that about 40 per cent
does come back. So more fresh water
is treated and added to it, and the
endless task goes on.
In the. chemical laboratory Of the
heating plant chemists are constantly
at work. testing the treated water
every three hours. and between times
making other tests. both for the plant
itself and for branches of the organ
ization requesting expert advice.
Inevitably, using such tremendous
quantities of coal, accessibility to trans
portation was an important item in the
location of the plant. So site was
selected at c street between Twelfth
and Thirteenth streets, SW., adja-
cent to one of the citys main rail-
road yards.
One of the most interesting of the
many experiences to be enjoyed on a
visit to the heating plant is following
the route of the coal from the railroad
car to furnace. From the time the
coal arrives in the yards until it lands
in the fiery furnace, it is untouched
by human hands. Leaving the trains
in the railroad yards, it takes one Of
two routes. A large amount. currently
needed to keep the plants fires going,
moves in a steady stream on smooth
ly running belts into the building and
into huge hoppers from which it is
mechanically fed into the furnace by
automatic stokers.
Instead of being shoveled on top of
the fires, as happens in the furnaces
with which most of us are best ac-
quainted, the robot-furnaceman pushes
his coal in beneath the fire, and as
more coal comes in, the previous stok-
ing is pushed upward, until event.
ually it is burning merrily on top
Of the pile.
En- route to. the boiler room the coal
is weighed automatically while in mo-
tion, by means of machinery somewhat
resembling phonograph record. Coal
not required for immediate use Is car
ried to the coal storage yard, where
approximately 10000 tons are kept In
storage for emergency.
THE cleanliness of the plant and the
inconspicuous disposal of the resi-
due from the fires are amazing in view
OF the hundreds Of tons of coal-and
soft coal at that-used in the daily
operation of the plant. The ashes@ol-
low the route of the coal, but in re-
verse direction. After first being
dropped into hoppers beneath the boil
ers,. they are sluiced into what IS
known as an ash sump pit in the base
ment Of the boiler house.
A large part Of this operation may be
watched by the casual visitor. One
may look through an open doSr into
the hopper, and see the ashes being
broken up and washed downward into
trough. Then at points in the floor,
traps may be raised, to see the water
running below carrying the ashes. But
one almost has to take this part Of the
operation on faith-or on the word of
the the engineers-for so rapidly is
the water moving that it is almost
impossible to see the burden 1t H
carrying.
And so the ashes 60 into the sump.
through grinder, and out by way Of
pumps and pipes to the ash bunkers In
the railroad yard, where, In an incon-
spicuous little house, ash and hue dust
(21a tons day of the latter In winter)
are separated from the water and the
ashes loaded on trucks. AS with the
coal, the handling of the ashes Is au-
tomato.
Although it is expected that some
day the ashes will be loaded on rail-
road cars and sent out Of the city,
so. far there has been no surplus, the
city of Washington at present taking
the whole supply for the building Of
bride paths In its National Capital
Parks system, also under the super