THE COLLIERY GUARDIAN
AND
JOURNAL OF THE COAL AND IRON TRADES.

Vol. CXI.	FRIDAY, MAY 26, 1916.	No. 2891.

Ash, Clinker, and Dust Separators.*

By M. BUHLE.

In the working of boiler plant, the removal of hot

ashes and clinker is a source of trouble and expense, the
men being exposed to heat and dust, and an excess of
air finding its way into the firebox.

These inconveniences led to the introduction of the

The hopper is constructed of brickwork or sheet metal,

and terminates in a short length of cast or wrought
pipe a, under which is a shallow cast-iron receptacle b,
containing a constant level of water into which the pipe
a dips, thus forming a seal which shuts off the hopper

Schwabach ash. remover (figs. 1 and 2), in which the hot
ashes drop directly from the ashpit hopper, through a
downpipe into a water seal, where they are quenched.
Thus the ash is removed without admitting air into the

from the outside air. The receptacle b is mounted on
the slope, and houses a cast-iron wheel c, pivoted on a
shaft d, and provided with vanes e, which scrape out the
ashes, etc., from b, as the wheel is rotated, and dis-

firebox, and is obtained in a dustless condition. The
hoppers a, b, and c, under each grate, are grouped so
that the ashes and clinker from all the boilers fall

charge them over the edge / into a truck, bin, etc. The
wheel c is driven by a small (0’1 .horse-power) electro-
motor, through worm gearing g. The ashes, etc., are
discharged as soon as deposited, and, being fully

In contrast to hand labour, the process of removing
ashes by suction offers many ad vantages, the work being
cleaner and unobjectionable on the score of hygiene,
besides being more thoroughly performed. The damper
can be kept closed, and consequently no cold air is
admitted into the flues to lower the efficiency of the
boiler. The boiler-house is left perfectly clean, the
ashes being removed through pipes; and in the case of
new plant the suction apparatus can be fitted bo as to
enable the work to be carried on without interfering with
the working of the bolters.

The following example illustrates the relative cost of
removing ashes by hand and with a suction device, and
applies to two large flame-tube boilers fired with brown
coal and waste wood. The hand work was performed by
five men, who took away 4 tons of flue ash in 37 working

Fig. 1.—Cross Section.

Fig. 2.—Longitudinal Section.

Schwabach Ash Conveyor.

quenched, there is no trouble from dust, injurious gases,
or the like, No labour is required, except to take away
the full trucks or bins at fairly long intervals and replace
them by empties.

Fig. 3.

directly through the downpipes into the quenching
trough, which is recessed in a block of concrete e, serv-
ing to support a light iron superstructure /. The edges
of the trough carry rails for the rollers g of the chain
conveyor, which is provided with scrapers h.

To prevent injury to the concrete bed of the trough
by the scrapers these latter work on a bottom rail i, and
do not touch the concrete at all. The ashes lying on the
bottom form a protective layer, the depth of which is
equal to the height of this rail. The scrapers are
bucket-shaped, and perforated, so that nothing larger
than II-in. lumps will fall through and be likely to
damage the concrete, and the buckets are set very close
together, with the same object.

The travel along the trough is so gradual that the
clinker and ashes are quenched and cooled very
thoroughly. At the end of the trough (at k, fig. 2) the
bottom rises, so that the oncoming material comes up
out of the water and is discharged into a truck I, or into
bins or on to a belt conveyor. The working cost is con-
siderablv .reduced by all the waste from all the boilers
being discharged at one point; and no hand labour is
required for opening or closing the hoppers, or quench-
ing or discharging the ashes, etc.

At the head of the trough the chains are engaged by
the driving wheels m, and travel back to the rear end n
of the trough over rails on the top of the iron super-
structure. The drive, consisting of an electromotor o,
with worm-wheel and pinion gearing, is mounted at the
head end of the trough, so that the pull is on the laden
buckets. At the rear end the chains are passed over
guide pulleys p, fitted with a tension device to keep the
chains taut. The rate of travel being slow, the wear is
small, and the chains have a long working life. For the
same reason, the motive power required is small, being
less than 3 horse-power for a trough about 25 yds. long.

Another pattern of Schwabach ash conveyor, shown in
fig. 3, is intended for removing ashes and dust from
places where these are deposited in unusually large
quantities, such as flue-gas traps, etc.

* Gluckauf.

Suction Devices.

The application of suction devices for removing ashes
from boiler plant and dust from briquette presses, etc.,
is extending, though it is still customary in many works
to employ hand labour for shovelling out the flue dust

hours, at a total cost of 5 x 37 x 0'8 = 148s. With the
suction device, three men were able to deal with the
same quantity of ashes in 31 hours, at a cost of 74s. 6d.,
the cost of 45 kw. of current bringing up the expenses
to 79s. The pump employed was not constructed

Fig. 4.—Suction Plant for Cleaning Flues.

I ’1

i W



specially for the purpose, or the
work could have been carried out
in one-third less time.

A suction device constructed by
the Siemens-Schuckertwerke for
boiler ashes is shown in fig. 4,
at work in the boiler-house of an
electric power station to which
is attached a dust destructor. The
accumulations of ashes 'are very
large, and necessitated the pro-
vision of large ash collectors.
The pump used in this instance is
mounted on a small truck, and
delivers 4,300 litres of air per
minute, for am expenditure of
about 71 horse-power in the
motor.

The figure shows how a flue is
. cleaned from outside, through a
door. The dust settles down
in the two drums, situated
between the suction nozzle and

collecting in boiler chambers and flues. The quantity
of ashes varies considerably according to the class of fuel
used, being largest in the case of brown coal, wood, and
sawdust; and the deposition of ash in the flues greatly
reduces the steam-raising capacity of the boilers, fre-
quent cleaning out being necessary, which entails
stopping individual units of the plant for some consider-
able time. Moreover, the operation of shovelling out
the dust is a difficult one, especially in narrow flues, and
much inconvenience is caused by the clouds of dust
raised.

the pump, and these drums
can be run off on a truck when full. The 2-in. hosepipe
is of steel and asbestos.

In addition, the suction device can be used as a
vacuum cleaner for the engine-room, for cleaning filter-
cloths from the air filters attached to the generators and
compressors, and also, in combination with a small com-
pressor, for removing dust from inside the dynamo
machines.

The pump is particularly suitable for dealing with
dust, being valveless, and cooled by circulating water.
The rotary internal body, with oast-on vanes, is sur-