- j
Left Cottrell experimental
PP.r.tU4 ,n cement plant, with current off; right Pl.ot under identical
conditions with the current. Note .11 .b.ence of .moke or duSt fumes.
Turning Smoke Into Money
AMERICA sends million- "up in smoke" vcarly be
cause of the enormoui watte in the fuel used by
our industries. On the other hand, there is a mail
in Washington who has discovered how to turn smoke
into money, and he is now busily engaged in teaching
the rest of the country how to perform the same trick.
He does this by means of devices which, through elec
trical precipitation, not only reclaim vast wealth from
the smoke, dust and fumes of smelters, but at the same
tune redeem thousands of acres of near by land. As a
matter of fact, the curb which this man has put on
the smoke and dust nuisance his original aim now ac
tually bids fair to be, in some directions, the primary
reason for the running of certain of our industries.
The .smoke wizard who has accomplished these remark
able things is Dr. Frederick G. Cottrell, chief of one
of the government's greatest scientific agencies the
Bureau of Mine-. Dr. Cottrell has many claims to the
appreciation of his fellow
scientists. He is a man
who does things and says
little. He is that rare
thing, an American who
cares little for either
money or publicity. The
clearest proof of the pos
lessioa of the qualities of
the true scientist that Dr.
Cottrell has ever given, a
demonstration deemed to
be a model to be followed
by those of his kind, came
a decade ago, when he
made a discovery of such
practical value that it was
obviously capable of being
made to yield all the riches
any man might desire.
After having demonstrated
it possibilities Dr. Cot
trell gave it away. He
consistently refused all of
fers to make a fortune
out of his work, an!
when money began to pour
in on him in spite 01
himself he promptly got his friends together, formed
what is known as the "Research Corporation," and
turned the financial stream into the corporation, with
the provision that the funds were to be used to assist
struggling scientists whose hardships he alreal kl ew
An ironclad agreement was made that all profits from
his work go to the corporation and not to Dr. Cottrell
himself.
The first big contribution of Dr. Cottrell to science
was the electrical precipitation of particles of liquids
and solids, or, in popular terms, the elimination ot
smoke and rescue of smoke constituents hv a process ot
electricity. Undertaken at first to eliminate smoke as
a nuisance, the process showed that tin - called smoke
dust precipitated at big plants was worth m some cases
more than the product being manufactured.
It was in 1906, while he was working as assistant
prot.sor of chemistrv at the University ot California,
that the idea first came to I r Cottrell. California at
that time was much annoyed over fumes from smelters.
There were examples of it close to the university. AW
fumes were admittedly necessary to the running of the
smelters, but were a nuisance to everyone within their
radius. There was continued talk about it, but no om
suggested a possible remedy, excepting to remove the
Mneltera, Dr. Cottrell said little, but it was notice !
that he began spending all Ml -pare tune in the lahora
lory, He worked whenever he got I chance during the
lay and far into the night Finally he surprised his
friends at the universitv bv telling them that he had
discovered an "electrical precipitation process WWW
WOtlld do away with the smkc.
In a general wav his idea wai to renjOYe the sus
pended particles from the gates by the aid Ol electrical
discharges. His process was to ope rate b pacing tm
Kases, carrying the suspended, finely divided pai rtlCies,
between two systems of electrodes. ,,ne oi which WM
marie to carry a negative electrical charge, while tne
other carried a positive charge. .
The electrodes were to be charged by being cou
nted with a source of high voltage electricity, con
' ;,K of a high voltage transformer tor increasing the
By ROBERT H. MOULTON
'Ciwtcnt,,al UIt0 a work,ng voItage of from 20,000
to IUU,UO0 volts. A rectifier for changing alternating
current into direct current and a switchboard were to
provide the necessary control equipment. Dr. Cottrell
figured that the suspended particles, while passing be
tween the electrodes, would become electrically charged
and would be driven into pipes by the forces of the
electric field. The original laboratory experiments con
ducted by Dr. Cottrell were made with the apparatus
shown in the accompanying photographs, which clearly
show the effect of turning the electric current on and
off in a precipitator in which sulphuric acid mist had
been generated.
Dr. Cottrell had no money at the time he perfected
his invention. He
was distinctly
n a r u up in
those days, but
he was certain
he could elimi
nate the smoke
nuisance if given
a chance. It hap
pened about this
time that at Riv
erdale, a town
not far away,
there was a huge
cement factory,
which had like
wise become a
nuisance in the
communitv be-
Kich potash (in bats) reclaim
ed through dust precipitator at
a finuiil plant.
m ntfaffTMiMh "S& .3 KhIBS
DR P REDBRICK G COTTRBLL
cause the dust from it found
its way into the blossoms of
Ofinge groves near b) and 111
tcrfered with the development
of the fruit
The orange growers took
the matter into the courts and
spent hundreds of thousands
of dollars pressing and winning
their cases. The company then
tried the expedient of buyim
up the land at $1,000 an acft,
but found it couldn't Jtondgg
mcc More than $1,000,000
bad been ipent by the company
in hatio!l and still there was
no reliet m sigm. m
tCottnr'7oW th. firm that fie behoved his proc
Vi 5v its difficulty, but that it would CO a
" 'I n t of money to install it. He was
considerable an "um ' ' . . . The proc-
? 2 12 H HU i charm I, did
,ss was tatt " completfv. and it was
lrfA community to sacrfi.ee e.ther fa
H Ju ffm cement
collect on eetation and
cement plant or its oranges. The electrodes in the
smoke stacks of the cement plant yielded every day 100
tons of minute particles which would otherwise have
been spread out on the community. Although the plant
had a capacity of 5,000 barrels of cement a dav and
business was good, Dr. Cottrell suggested that the
concern might find it profitable to examine the dust
which his process collected. The firm did so and found
that it contained large quantities of potash, and potash
is the basis of one of the most valuable fertilizers in
the world. Since that time the company has manu
factured chiefly potash, obtained from the smoke dust
by the Cottrell process, and is only making cement as
a by-product. Thus a new and profitable means of
getting potash has been discovered. This is certainly
a romantic development of modern industry, where an
apparatus installed to save the life of the factory
turns out to be the center of the operations, around
which the entire plant is adjusted, the incidental profits
being sufficient to make the former operation of the
factory of secondary importance.
The success of the experiment at Riverdale at
tracted the attention of a smelter at Vallejo Junction,
located a few miles from the former place, which was
at that time the subject of injunction proceedings
brought by the farmers of the surrounding country.
Three separate stacks of the smelter contributed to the
alleged nuisance, the most serious offender of the lot
being one which handled the gases from the lead blast
furnace and discharged several tons of lead fume
daily into the air.
While this particular trouble was overcome by the
installation of a bag house before work was begun
with the electrical precipitators, there still remained a
stack which, besides discharging the gases from the
roasters, furnished dense white clouds, consisting chiefly
of sulphuric acid, arsenic, and lead salts, and to which
the bag house was not applicable because of the cor
rosive action of these gases on the bags. There was
still another stack which carried the mists escaping
from the pots of boiling sulphuric acid used in dis
solving the silver out of the gold and silver alloy com
ing from the cupels. The electrical precipitators in
stalled at this smelter by Dr. Cottrell proved eminently
satisfactory and was the first commercially successful
use of the method applied to this type of smelter. The
precipitators have now been in regular daily operation
for more than 12 years at a cost for
labor attendance and repairs of less than
$20 a month. As a matter of fact, the
plant made enough bluestone to utilize
all the weak acid recovered, so that the
saving on the purchase of the latter paid
for the entire cost of operating at least
five times over.
While the solution of the coal smoke
problem lies in better combustion, and
while what is here needed is not so much
I method of collecting smoke as one for
preventing its original formation, Dr.
Cottrell expresses the opinion that in
SOIM special cases, and probably for
some time to come, precipitation meth
ods may prove a stepping stone and a
useful adjunct. As an example, he
points to power plants which have a
very high power demand for a short
period during the day, as compared with
the rest of the time. Under such con
ditions it is impracticable to prevent the
production of a certain amount of black
smoke during the high power period
without providing a much larger fur
nace and boiler equipment than is re
quired for the average load. The in
stallation of precipitation apparatus
would prove more economic than the
addition of boilers and furnaces that
would otherwise be required.
The waste in metallurgical smoke which means
gases, vapors, and fine dust that issues from blast,
smelting and roasting furnaces runs into hundreds of
millions in money. To prevent that waste was really
the problem to which Dr. Cottrell addressed himself.
It is thought Dr. Cottrell's device will be generally
applied throughout industry in the near future, but none
of the earnings will benefit Dr. Cottrell the money
will all go to aid other struggling scientists.
manufacture
destroys life.
15