752

THE COLLIERY GUARDIAN.

October 20, 1916.

In the course of his reply, which, he said, he should
amplify for the institute’s Proceedings, Mr. Budge said
he also was one of those who did not think a 1 to 1
mixture sufficient, and believed that somewhere in the
neighbourhood of 65 per cent, of stone dust was what
should be aimed at. He had been asked to explain what
he meant by a 1 to 1 mixture. He had taken all
through his paper the system of analyses of the Explo-
sions in Mines Committee. Principal Griffiths had
shed much light on a matter that had puzzled him as
to the density of dust.

The discussion was further adjourned to a special
evening meeting of the institute.

COAL HANDLING PLANT BETWEEN
RAIL AND WATER.*

The Darrow-Mann Company, of Charlestown (Mass.),
has installed a novel coal handling plant at its wharf on
the Mystic River, which is connected with the Boston
and Maine railway by a double track running to the end
of the wharf, and is provided with an extra track for
storage or switching purposes. The two main tracks can
easily accommodate 50 ears, but 20 are usually
operated at a time.

The wharf itself is 600 ft. long by 100 ft. wide, leaving
a plot of land between it and the Boston and Maine of
approximately 900 ft. long by 100 ft. wide, thus ensuring
ample space for additional pockets, if needed. The
company has a berth 150 ft. wide and 30 ft. deep at mean
low water. Two ordinary steamers can dock at the
same time, or one large steamer and a barge or two. The
river channel, opposite the wharf, is about 900 ft. wide
and 30 ft. deep at mean low water.

igjSSi

i r

Loading Barges Alongside Dock.

Located on the wharf are the store pockets, having a
capacity of 7,000 tons each, or a total capacity of about
35,000 to 40,000 tons. If necessary, the company can
store more than 100,000 tons of coal by utilising the
unoccupied land. The pockets are equipped with three-
way hoppers of 50 tons each, so ears and lighters can be
loaded simultaneously. The pockets are 400 ft.
long. Above these are two travelling Mead-
Morrison towers, operated by electricity. These towers
can be operated fully 175 ft. back from a boat,
and each is equipped with a five-ton scoop that can
handle about 400 tons per hour. Another tower is to be
erected, and the three will then have a capacity of 1,200
tons per hour.

With its two towers the largest collier, which is of
12,500 tons capacity, can be unloaded in about ten
hours. The facilities for loading cars and lighters are
equally as excellent as those for unloading steamers and
barges. Very often 20 cars have been loaded in two and
a half minutes, and during a recent test 67 cars were
loaded in 51 minutes. In ordinary working the 20 cars
are loaded in about 3 minutes, including the switching
in and out of cars, and this speed can be maintained
throughout the day. At the same time, 350 tons of coal
per hour can be weighed into lighters. The company
operates two lighters—one of 1,200 tons capacity and the
other 1,000 tons. They are used in connection with the
retail trade in and about Boston. The largest can be
loaded in three hours and the other in two and a half
hours. The management is figuring on handling more
than a million tons annually when the third tower is
completed and the company’s fleet of steamers is in
operation.

The scales for weighing in and out of cars are located
conveniently near the point where the yard trackage
joins the railway. The construction of the plant is such
and the method of unloading barges and steamers and
loading of cars and lighters so simple that operating costs
are exceptionally low. The total number of men
employed is eight—two tower men, two weighers, three
wharfmen and an electrician.__________________________

* Black Diamond.

FUEL ECONOMY AND THE SMOKE
NUISANCE.

Gas v. Low-Temperature Carbonisation.

Addressing the half-yearly meeting of the members
of the North of England Gas Managers’ Association, held
at Newcastle on October 7, Mr. Wm. Hardie, of Tyne-
mouth (acting president) stated that the question of fuel
economy was receiving considerable attention at present,
and was worthy of future research work. An important
point was the question of the most suitable temperature
at which to carbonise coal for its gaseous, solid and
liquid products. Since the commencement of the war
an idea had taken hold of some would-be leaders of
public opinion that the methods of using coal, and even
of carbonising coal, were all wrong, and that the time
had arrived when the Government should take in hand
and stop all present methods by drastic means, and
should practically prohibit the use of coal except in
the particular pet ways of these gentlemen. Such
action, to his mind, appeared to be rather in the
nature of dictating to research than being guided
by it. The scheme at present in favour of
coal was low-temperature carbonisation; but this had
not, so far as he could learn, been a commercial success.
With regard to waste in smoke, some had failed to
appreciate the remarkable extent to which the smoke
nuisance had been and was being abated by the gas
industry, in the gr adual displacing of crude coal by gas
coke and purified gas, both for domestic and industrial
purposes ; and it only needed the proper encouragement
and assistance by scientific men or the Government to
increase a thousandfold the effective work already done
in that direction. Apart from this, however, the gas
industry was in a sufficiently prosperous position to be

able to support a Research Committee which would be
able to thoroughly investigate and give an authoritative
opinion upon many subjects which required solution in
the interests of the gas industry. Such a Research
Committee could act undei- the guidance, if need were,
of the institution. If all, or the majority, of the gas
undertakings would agree to pay an annual subscription
fox’ this purpose, on somewhat similar lines to the grant
to the British Commercial Gas Association, they would,
he felt sure, be more than repaid by the valuable
research work achieved. Mr. Hardie concluded his
address with a detailed description of the high-pressure
distribution schemes which were being undertaken by
his company with a view to supplying distant townships
and colliery districts at Seaton Delaval, Hartley and
Seaton Sluice with gas.

A Coke Handling Plant.

Mr. A. B. Walker gave a description of the coke-
handling plant at the Howdon Lane Gasworks, where,
from the time the coals are tipped out of the trucks
until the coke is put into wagons or stacked in the
yard, the man with the shovel is never in evidence. On
leaving the mouthpiece of the retort the coke is
discharged on to a semi-spiral inclined shoot, arranged to
take the three levels of retorts (eight in each oven), and
to deposit the same gently on to the hot-coke conveyor.
This shoot obviates damage to trays, and reduces
the production of breeze. It can easily be managed by
one man, even without gearing. The hot-coke
conveyor is formed of a series of steel trays bolted
together so that each forms a link of the chain.
Corrosive action is scarcely noticeable. At first, each
tray was carried on wheels, which travel on a renewable
flat steel strip in the bottom of the trough, and also on
the return rail. During the past 12 months, however,
there has been only one set of wheels to each alternate
tray. The wheels and knuckle joints are bushed with
manganese steel bushes (also renewable). The original
wheels are still in use, but they have been re-bushed,
and new bolts fitted. This will in future be the
heaviest part of the renewals, as the bushes and bolts

wil require replacing at least every year. The knuckle
joint bolts show little or no wear, and will easily bear a
life of foni’ years. The trough of the conveyor is made
of cast iron, and is anchored at its centre to the
supporting cross joists, thus leaving it free to expand
eitbei- way. The bottom of the trough is kept clean
by a series of scrapers fastened to the trays at
intervals. The tension on the chain is given by
balance weights suspended over pulleys. To the
tension weights is fixed an adjustable lever arranged in
such a way that, were anything to break, the tension
weights would only drop J in., whereupon the lever
would engage the trigger of an ehctric cut-out and stop
the whole conveyor. The cutting-off of the current
prevents any piling up of the trays at the delivery end.
This device has only come into operation once, and its
efficacy was proved, on that occasion, by the fact that
the conveyoi’ did not travel more than a couple of feet
after the current was cut off. On the standard carrying
the tension gear is fixed a wood block, which can be
raised ox- lowered as required. The top of this block is
about Jin. below the trigger level, and serves to catch,
and hold, the balance weights should a breakdown
occur, saving labour in getting the weights into position
again as well as a lateral movement of the trays. The
conveyoi- is driven by means of worm gearing, all totally
enclosed. The wheel rail is raised at each end, fox- two
reasons : (1) to get as large driving and following wheels
as possible, and (2) to resist the rush or wave of the
water at the discharging end. The extra depth of
water at this point also acts in washing the small breeze
and dust out of the coke. This small breeze is carried
by the water into a filter. On leaving the horizontal
conveyor, the coke drops on to a shaker, which changes
the direction of travel by 90 degs., feeding it on to the
trays of the inclined conveyor. The rate of delivery by
this shaker is regulated by the length of the stroke ; the
adjustment being made on the eccentrics. It is operated
by the same drive as the horizontal conveyor. The
shakei’ is large enough to hold fully one charge of coke,
and is served by water’ sprays to be used when required
—i.e., when the three ovens nearest the discharging end of
the shoot are in commission. The elevating conveyor is
formed by trays carried on wheels; the tray being
fastened to the wheel spindle. The wheels travel on
renewable flat steel paths. At two points arrange-
ments have been made to tip the coke, the first
discharging into the yard and the second into the coke
breaker. At the top the coke falls on to a curved shoot,
which delivers into the centre of the hopper. By using
this curved shoot, the velocity of the coke leaving the
elevator is diminished; the result being that the breakage
through dropping into the hopper is lessened consider-
ably. The elevating conveyor is operated by means of
a worm drive at the top end. From the hoppei’ the
coke may be discharged into carts or over the screens
into railway trucks. These screens are of a new design,
and give the coke the same movement as it imparted to
it by shaking it on a coke fork. Sets of tapered fingers
are so arranged that the coke on leaving each set turns

1	art y over, thus allowing the loose bits of already
formed breeze to fall off the pieces of coke. The
delivery capacity of these screens is large. Coke,
properly screened, has been passed ovex’ one screen,

2	ft. 9 in. wide, at the rate of 60 tons pex- hour. The
tipping of the coke into the breaker- has already been
mentioned. The rollers of the breakei’ are set to give
coke broken into pieces about 2 in. cube The resultant
is screened into three sizes: duff, nuts and unscreened
coke, the lattei’ being discharged at the end of the
screen. The breakei’ is driven by a chain from a countei’
shaft at the top of the elevator, and can be put in or
out of action by means of a clutch. The broken coke
and breeze are collected in separate hoppers, from which
the material is loaded into carts. The stacking of the
coke is done by means of an electrically driven
crane, carrying 2 tons at 50 ft. radius, and a skip
with a bottom opening in two halves. The coke
is passed ovex’ the screens into the skip, hoisted and
swung to the spot, so that the bottom is about 3 ft.
above the level of the stack. The doors are then
opened, and the coke falls into position. The quenching
of the coke is done by town’s water on the “ A ” section
of the ovens, and by pump water on the “ B ” section
and the shaker. The watex’ runs off at the discharging
end of the trough, and at first was taken directly into a
well, from which it was pumped. Considerable trouble
was, however, caused by small pieces of coke fouling the
pump valves. On investigations being made, a large
amount of small breeze was found round tbe strum of
the suction pipe. Several methods fox- intercepting the
small breeze was tried, but it was not until a bi-eeze
filtei’ was erected that success was obtained. All tbe
water from the trough and shakei’ is conducted into a
square brick tank underneath the retort stage. This
tank fills gradually with the small breeze, which is
really the filtering medium. A portion of the deposit
is removed daily and carted to the boiler to be burned.
On leaving the filter, which it does by going ovex’ a weir
fitted with a breeze arrester, the watex- flows along a
brick trough towards the storage well. In this trough
weirs are placed at intervals, to arrest any breeze that
may settle, and brushes, through which the watex-
passes, arrest any glut that comes along. The result is
practically clear’ water, the storage tank having to be
cleaned out only once a year. The average percentage
of watex- in the coke during last yeax- was 3’92. The
starting switchboard is situated on the retort-house
floor, and is ari’anged so that the elevating conveyor
must be started before the hot-coke conveyor, and
again that the latter must be stopped before the former.
This prevents any possibility of jamming at the point
where the coke is fed on to the elevating conveyor. To
start up, the main switch is first put in, and then the
elevating conveyor’ is started by means of the rheostat,
aftei- which a button is pressed starting the horizontal
conveyor.