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THE COLLIERY GUARDIAN.

May 11, 1917.

CURRENT SCIENCE

Ontario Nickel Commission Report.

The Royal Ontario Nickel Commission; composed of
Messrs. G. T. Holloway (chairman), W. G. Miller, and
McG. Young, K.C., Mr. T. W. Gibson, Deputy-
Minister of Mines, acting as secretary, has presented
its report to the Ontario Government.

The Commissioners say that in their opinion: —

(1)	The nickel ore deposits of Ontario are much
more extensive and offer better facilities for the pro-
duction of nickel at a low cost than do those of any
other country. Nickel-bearing ores occur in many parts
of the world, but the great extent of the deposits in
this province, their richness and uniformity in metal
contents, and the success of the industry, point
strongly to the conclusion that Ontario nickel has little
to fear from competition.

(2)	Any of the processes now in use for refining
nickel could be successfully worked in Ontario, and
conditions and facilities are at least as good in this
province as in any other part of Canada.

(3)	In view of the fact that practically no chemicals
are required, that there is a much more complete
saving of the precious metals, especially platinum and
palladium, and that electric power is cheap and abun-
dant, the most satisfactory method of refining in
Ontario will be the electrolytic.

(4)	The refining of nickel in Ontario will not only
benefit the nickel industry, but will promote . the
welfare of existing branches of the chemical and metal-
lurgical industries, and lead to the introduction of
others.

(5)	The methods employed at the Ontario plants of
the two operating nickel companies are modern and
efficient, although there are differences in both mining
and smelting practices. It is the consistent policy of
both companies to adopt all modern improvements in
plant or treatment. Even during the present time of
acute pressure, the Canadian Copper Company has
materially increased its output without substantial
enlargement of its plant, and the losses in smelting
are less, both at Copper Cliff and the Mond plant at
Coniston, than they were a year ago. These com-
panies have each had their experimental stage, neither
has asked nor received any Government assistance,
and both have earned the success which they have
achieved.

(6)	The present system of mining taxation in
Ontario is just and equitable, and in the public
interest, and is the best system for this province. Any
question of change is rather one of rate than of
principle.

(7)	Experiments have been undertaken by the Com-
mission in the production of nickel-copper steel direct
from Sudbury ore, and also in the electrolytic refining
of nickel. Certain improvements in the latter process
have been made the subject of application on behalf of
the Government of Ontario for patents in Canada, the
United States, and Great Britain.

In this connection, it is reported that the nickel '
refinery at Port Cojborne, now under construction,
which is expected to be in operation before the end of
the year, will consume annually 100,000 tons of
materials such as bituminous coal, coke, fuel oil, nitre
cake, and other chemicals. The output will be at the
rate of 15,000,000 lb. nickel per year.

Industrial Use of Coal Gas in War Time.

In a paper read before the Royal Society of Arts on
the 18th ult., Mr. H. M. Thornton gave a number of
reasons for the popularity of the gas furnace. It
economised valuable labour, as no stoking was
required; no fuel had to be transported or stored; no
clinkering had to be done ; no ashes had to be removed ;
very much less time was lost waiting for the furnace to
heat up. Existing factories had to be utilised to the
full extent of their capabilities; and here the gas
furnace, compact, self-contained, and mobile, showed
to advantage. It gave economy in space, and made
possible an increase in output per unit of factory area.
No smoke stack was required; the choice for the posi-
tion of the furnace was practically unlimited, enabling
it to be brought into close proximity to the machine
worker. No space was required for the storage of fuel
or ashes. The capital expenditure in many cases was
lower thaii for coal furnaces. No special structural
alterations to the factories were required ; no founda-
tions were necessary; no provision had to be made for
the extraction of smoke, soot, or dust from the
workshop.

The most vital need was for an instantaneous, and
yet abnormal, acceleration in production. The gas
furnace, with its easy, accurate control of tempera-
tures, and its constancy of action, “ speeded up ” the
output, increasing the number of operations—anneal-
ing, hardening, melting, etc.—per working day by, in
many cases, 100 per cent, over crude heating methods.
Its fuel was always available, and at a constant calorific
value. With reasonable care, there was no spoilt work
and no “rejects” owing to irregular heating. The
time required for each operation could be definitely
ascertained, and the work could be performed at a
uniform speed, enabling the works manager to depend
on a constant supply of his heat-treated materials for
the other departments of the factory.

In the production of munitions, the gas furnace is
used for annealing bars of tool steel and steel billets,
for the 11 nosing” or “bottling” operation of shells,
for the heat treatment of armour piercing shells, and
for stoving the shells after varnishing; in the manu-
facture and repair of howitzers and guns from the
short 4-5 in. howitzer to the long naval gun; for the
hardening and case-hardening of rifle parts, and for
annealing rifle breeches.

The use of gas furnaces in the manufacture of tools
of all kinds—cutters, reamers, lathes and planing tools,
broaches, etc.—has expanded enormously since the war
began. The careful heating of high-speed steel to
critical temperatures, so necessary for good results, is
accomplished perfectly with gas. Piercers or punches

AND TECHNOLOGY.

for shell bodies, spade cutters for shell boring, taps,
dies, twist drills, broaches, and many other tools neces-
sary for engineering work, are all hardened in gas
furnaces, and the heat treatment of the special alloy
steel used for the plates for the steel helmets of our
soldiers is performed in low-pressure gas and air fur-
naces. Case-hardening, annealing wire, and heating
the dope room for drying aeroplane wings, etc., are all
accomplished by means of gas furnaces or radiators.

The author Concluded by describing the application
of gas in the non-ferrous metal trades, in welfare
work in factories, and discussed the future possibilities
of the extended use of this fuel.

Refractories from Fused Bauxite.

In La Ceranlique, M. N. Lecesne gives the follow-
ing account of a method of preparing refractory
materials, suitable for furnace linings and similar
purposes, from fused bauxite: —

One part of crushed anthracite is mixed with three
parts of average bauxite — containing about 60 per
cent, of alumina, 10 per cent, of iron sesquioxide, and
10 per cent, of silica—in its natural state of moisture,
and the mass is charged into a furnace, lined with
refractory brick, previously heated up with an anthra-
cite fire. An air blast is employed, at an initial pres-
sure of about 40 in. water gauge, increasing to a maxi-
mum of 400 in. according to the thickness of * the
charge, though the average maximum pressure does
not exceed 160 in. water gauge. The temperature
quickly rises, and the bauxite is disintegrated by the
sudden evaporation of its contained moisture. The
mass is gradually transformed into aluminium carbide,
which burns and raises the charge to a high state of
incandescence—approximately 3,000 degs. Cent. At
the same time, the silica is driven off as dense white
fumes, and the iron oxide is reduced to the metallic
state, in which condition it is blown out of the furnace
as a shower of sparks, oxidising to magnesic oxide on
contact with the outer air. The air blast is continued
for some time, to burn off the surplus anthracite and
cool down the mass, the latter being discharged from
the furnace without difficulty. The product, which is
virtually corundum, intimately mixed with fine par-
ticles of unconsumed carbon, is ground, mixed with a
binding medium, shaped in moulds, dried, and fired in
the same way as calcined bauxite. If the fusing
process be carried out in about three hours, the product
will be of the desired degree of porosity. By mixing
nine parts of this corundum with one part of bauxite
and a little milk of lime, a product is obtained that is
suitable, when fired, for lining reverberatory furnaces,
and those heated by gas or liquid fuel.

The Nitration of Toluene.

In United States Bureau of Mines Technical Paper
No. 146, Mr. E. J. Hoffman outlines the most favour-
able method of preparing trinitrotoluene. The acid
used in the first stage of the nitration of the toluene
should be a mixture of two parts by weight of sulphuric
acid of specific gravity 1-84, and one part of nitric acid
of specific gravity 1-42, the weight of nitric acid taken
being 50 per cent, in excess of that required theoretic-
ally for the conversion of all the toluene into mono-
nitrotoluene. For 50 grms. of toluene, 73-38 grms. of
nitric acid is used. To the mixed acid contained in
the nitrating vessel, provided with apparatus for cool-
ing and stirrjng, and cooled to 20 degs. Cent, or lower,
the toluene is added gradually, with constant stirring,
the rate of introducing the toluene and the cooling of
the reacting mixture being so regulated that the tem-
perature does not exceed 30 degs. Cent. When
approximately 70 per cent, of the toluene has been
added, the nitration becomes much slower, and little
cooling of the mixture is required. When the total
amount of the toluene has been introduced, and the
temperature ceases to rise, the cold water surrounding
the nitrating vessel is allowed to run out, while the
operation is continued about half an hour longer.
After the contents of the nitrating vessel have stood
for some time, preferably over-night, the spent acids
are removed by gravity from the supernatant crude
mbnonitrotoluene, which consists of a mixture of
mononitrotoluenes and dinitrotoluenes.

The mixed acid used in the first step in the conver-
sion of the crude mononitrotoluene into trinitrotoluene
consists of equal weights of sulphuric acid of specific
gravity 1-84, and of nitric acid ©^specific gravity 1-5,
the nitric acid content being 50 per cent, in excess of
that required theoretically to convert the calculated
yield of mononitrotoluene into dinitrotoluene. For
the product derived . from 50 grms. of toluene,
54-58 grms. of nitric acid is taken. The crude mono-
nitrotoluene is dissolved in sulphuric acid having a
specific gravity of 1-84, the weight of the acid being
equal to the weight of mixed acid, and is heated to
50 degs. Cent. The mixed acid is added gradually,
with constant stirring, over a period of at least one
hour, during which time the temperature should not
exceed 100 degs. Cent. After all the acid has been
introduced, the mixture is heated for two hours at a
temperature of 90 to 100 degs. Cent.

At this point, the acids in the nitrating vessel,
cooled to about 90 degs. Cent., are concentrated by the
addition of 15 per cent, oleum, equal in weight to the
weight of the mixed acid to be. used in completing the
nitration. If the oleum is added slowly, little rise in
temperature occurs. The mixed acid used consists of
equal weights of nitric acid (specific gravity 1-5) and
15 per cent, oleum, the nitric acid taken being double
that required theoretically to convert into trinitro-
toluene the nitration products calculated as dinitro-
toluene. On the basis of 50 grms. of toluene,
72-78 grms. of nitric acid is used. The mixed acid is
added gradually, with continued stirring, while the
temperature is allowed *to rise up to, but not above,
115 degs. Cent. When approximately 75 per cent, of
the acid has been introduced, heating is required to
maintain the temperature above 100 degs. Cent. A

minimum time of two hours should be allowed for the
introduction of the acid. When the addition of acid
has been completed, the heating is continued for two
hours longer, a temperature of 90 to 117 degs. Cent,
being maintained, but the latter temperature should
not be exceeded.

Upon the completion of the nitration, the reaction
mixture is allowed to cool in a vessel adapted to the
subsequent removal of the spent acid. After standing
at least 18 hours, the crude trinitrotoluene will have
separated as a solid cake and suspended crystals.
After the underlying spent acid has been drained off,
the crude product is crushed, washed well with cold and
hot water, dried, etc., as previously described. A
higher degree of purity may be obtained by washing
with the alcohol-benzene mixture. The spent acid
contains in solution additional trinitrotoluene, as well
as lower nitration products, which may be recovered
by precipitation in water. In practice, the spent acid
is used over again after renewal by the addition of
fresh acids.

MINE WATER AS BOILER FEED*

By Edwin M. Chance.

Some years ago an unusually severe dry spell
threatened to cause the majority of the collieries in
the southern anthracite field of the United States to
suspend operations. This drought occurred in the fall
of the year, and as the water companies supplying this
region drew their supply for the most part from
reservoirs fed by surface water, and as these reser-
voirs, due to the shrinkage in their supply, were well
nigh dry, the situation was extremely serious.

The company with which the author was connected
at that time made every effort to meet the emergency
by installing small Dumping stations on streams within
a radius of about 10 miles of its mines, and hauling
water in tank cars for its boilers. The supply thus
secured proved entirely inadequate, so’ that other
means for maintaining a supply had to be resorted to,
if the mines were to be operated or even kept free of
water.

Under similar conditions, the practice in the past
had been to attempt to purify the mine water for use
as boiler feed by neutralising its acidity with slaked
lime, and for this purpose each boiler plant was
equipped with one or two treating tanks of about
10,000 gals, capacity, and from six to eight settling
tanks of about 5,000 gals. each. The results with this
method of treating mine water had been most unsatis-
factory, as the effect upon the boilers of this treated
water was decidedly unfortunate. As a matter of fact,
the use of lime tended to lessen the corrosive effect of
the raw mine water, but, on the other hand, increased,
if anything, its scale-forming proclivities.

Because of the high acidity of the waters to be
treated, and the great weight of encrusting solids to
be removed, it was obvious that only the cheapest of
chemicals could be used, were the cost of the treatment
to be kept within reasonable limits. The following
typical analysis will illustrate this point, if the fact
be kept in mind that the mean daily consumption of
boiler water per colliery was in the neighbourhood of
120,000 gals., and over 20 collieries were short of
water: —

Typical Analysis of Anthracite Mine Water.

Parts per
Appearance, yellow turbid.	million.

Free sulphuric acid, H2SOd (to methyl orange)... 160
Total acidity, H2SOd (to phenolphthalein) ... 1,200

Oxides of iron and aluminum (Fe —Al)203 ....... 500

Lime, CaO .........;........................... 200

Magnesia, Mg	............................... 200

' Total sulphuric	acid, SO3 (gravimetric) ..... 1,500

Total solids ............................... 3,000

It should be remembered that the water, the
analysis of which is given above, is only moderately
acid, many waters being 10 times as polluted as this.

Were this water treated with slaked lime, its acidity
would be destroyed, its iron and alumina, and about
half its magnesia, would be removed. Its lime con-
tent, however, ivould be increased to about 800 parts
per million, and such lime would exist entirely as
calcium sulphate. Such a water would be so fright-
fully encrusting as to quickly ruin the boilers in which
it was used.

Use of Slaked Lime and Soda Ash.

After a careful consideration of the urgency of the
case, and the means at hand, it was decided to destroy
the acidity of the waters to be treated by the use of
slaked lime, and then to precipitate as much of the
calcium sulphate as possible by the use of soda ash
(crude dry sodium carbonate).

In carrying out this process, the water was pumped
to one of the large treating tanks, and there heated to
as high a temperature as possible by exhaust steam
from the breaker engine, or any other prime movers
in the vicinity. As a general rule, there was no diffi-
culty in heating the water to a temperature of 65 degs.
Cent. (150 degs. Fahr.). In some cases, it was found
advisable to use some live steam with the exhaust, as
a slight increase in the temperature of the water
greatly increases the rapidity, efficiency, and complete-
ness of the treatment. After the water had reached
the desired temperature, slaked lime was run into the
tank, the contents of which were stirred vigorously,
until a sample of the water gave a pronounced and
permanent pink colour when a few drops of phenol-
phthalein solution were added to it.

It is to be noted that the addition of the slaked lime
causes a voluminous precipitate of the hydroxides of
iron and aluminum, and that when the point of com-
plete neutralisation is approached, this precipitate
begins to settle rapidly, leaving a foot or so of per-
fectly clear water at the top of the tank. This appear-
ance is characteristic, and permits the man in charge
of the treatment to judge, with fair accuracy, when
sufficient slaked lime has been added. Thus, it is only
necessary to test the water with the phenolphthalein

* Coal Age.