Nothing is in more general use than petroleum, and but few things are
known less about by the majority of persons. It is hydra-headed. It
appears in many forms and under many names. "Burning fluid" is a popular
name with many unscrupulous dealers in the cheap and nasty. "Burning
fluid" is usually another name for naphtha, or something worse.
Gasoline, naphtha, benzine, kerosene, paraffine, and many other
dangerous fluids which make the fireman's vocation necessary are all the
product of petroleum. These oils are produced by the distillation or
refining of crude petroleum, and inasmuch as the public, especially
firemen, are daily brought into contact with them it is proper that
they should know something of their properties. Refining as commonly
practiced involves three successive operations. The apparatus employed
consists of an iron still connected with a coil or worm of wrought-iron
pipe, which is submerged in a tank of water for the purpose of cooling
it. The end of this pipe is fixed with a movable spout, which can be
transferred or switched from one to another of half a dozen pipes which
come around close to it, but which lead into different tanks containing
different grades of the distillate. When the still has been filled with
crude oil the fire is lighted beneath it, and soon the oil begins to
boil. The first products of distillation are gases which, at ordinary
temperatures, pass through the coil without being condensed, and escape.
When the vapors begin to condense in the worm the oil trickles from the
end of the coil into the pipe leading to the appropriate receiving tank.
The first oil obtained is known as gasoline, used in portable gas
machines for making illuminating gas. Then, in turn, come naphthas of
a greater or less gravity, benzine, high test water white burning oil,
such as Pratt's Astral common burning oil or kerosene, and paraffine
oils. When the oil has been distilled it is by no means fit for use,
having a dirty color and most offensive smell; it is then refined. For
this purpose it is pumped into a large vat or agitator, which holds from
two hundred and fifty to one thousand barrels. There is then added to
the oil about two per cent, of its volume of the strongest sulphuric
acid. The whole mixture is then agitated by means of air pumps, which
bring as much as possible every particle of oil in contact with the
acid. The acid has no affinity for the oil, but it has for the tarry
substance in it which discolors it, and, after the agitation, the acid
with the tar settles to the bottom of the agitator, and the mixture is
drawn off into a lead-lined tank. After the removal of the acid and tar,
the clear oil is agitated with either caustic soda or ammonia and water.
The alkali neutralizes the acid remaining in the oil, and the water
removes the alkali, when the process of refining is finished. A few
refiners improve the quality of their refined oil by redistilling it
after treating it with acid and alkali. All distillates of petroleum
have to be treated with acid and alkali to refine them. There is one
thing peculiar about the distillates of petroleum, and that is that the
run which follows naphtha, which is called "the middle run oil," is the
highest test oil that is made, running as high as 150 and 160 degrees
flash, while the common oil which follows, viz., from 45 down to 33
degrees Baume, will range at only about 100 flash, or 115 and 120
degrees burning lest.
An oil that will stand 100 flash will stand 110 burning test every time.
Kerosene oil, at ordinary temperature, should extinguish a match as
readily as water. When heated it should not evolve an inflammable vapor
below 110 degrees, or, better, 120 degrees Fahrenheit, and should not
take fire below 125 to 140 degrees Fahrenheit. As the temperature in a
burning lamp rarely exceeds 100 degrees Fahrenheit, such an oil would
be safe. It would produce no vapors to mix with the air in the lamp and
make an explosive mixture; and, if the lamp should be overturned, or
broken, the oil would not be liable to take fire. The crude naphtha
sells at from three to five cents per gallon, while the refined
petroleum or kerosene sells at from fifteen to twenty cents. As great
competition exists among the refiners, there is a strong inducement to
turn the heavier portions of the naphtha into the kerosene tank, so as
to get for it the price of kerosene. In this way the inflammable naphtha
or benzine is sometimes mixed with the kerosene, rendering the whole
highly dangerous. Dr. D. B. White, President of the Board of Health
of New Orleans, found that experimenting on oil which flashed at 113
degrees Fahrenheit, an addition of one per cent. of naphtha caused it to
flash at 103 degrees; two per cent. brought the flashing point down to
92 degrees, five per cent. to 83 degrees, ten per cent. to 59 degrees,
and twenty per cent. of naphtha added brought the flashing point down to
40 degrees Fahrenheit. After the addition of twenty per cent. of naphtha
the oil burned at 50 degrees Fahrenheit. There are two distinct tests
for oil, the flashing test and the burning test. The flashing test
determines the flashing point of the oil, or the lowest temperature at
which it gives off an inflammable vapor. This is the most important
test, as it is the inflammable vapor, evolved at atmospheric
temperatures, that causes most accidents. Moreover, an oil which has
a high flashing test is sure to have a high burning test, while the
reverse is not true. The burning test fixes the burning point of the
oil, or the lowest temperature at which it takes fire. The burning
point of an oil is from ten to fifty degrees Fahrenheit higher than the
flashing point. The two points are quite independent of each other; the
flashing point depends upon the amount of the most volatile constituents
present, such as naphtha, etc., while the burning point depends upon the
general character of the whole oil. One per cent. of naphtha will lower
the flashing point of an oil ten degrees without materially affecting
the burning test. The burning test does not determine the real safety
of the oil, that is, the absence of naphtha. The flashing test should,
therefore, be the only test, and the higher the flashing point the safer
the oil.
In regard to the danger of using the lighter petroleum oils, the
following, under the head of "Naphtha and Benzine under False Names," is
taken from Prof. C. F. Chandler's article on "Petroleum" in Johnson's
Cyclopedia. He says: "Processes have been patented, and venders have
sold rights throughout the country, for patented and secret processes
for rendering gasoline, naphtha, and benzine non-explosive. Thus
treated, these explosive oils, just as explosive as before the
treatment, are sold throughout the country under trade names. These
processes are not only totally ineffective, but they are ridiculous.
Roots, gums, barks, and salts are turned indiscriminately into the
benzine, to leave it just as explosive as before. No wonder we have
kerosene accidents, with agents scattered through the country selling
county rights and teaching retail dealers how to make these murderous
'non-explosive' oils. The experiments these venders make to deceive
their dupes are very convincing. None of the petroleum products
are explosive _per se_, nor are their vapors explosive under all
circumstances when mixed with air. A certain ratio of air to vapor is
necessary to make an explosive mixture. Equal volumes of vapor and air
will not explode; three parts of air and one of vapor gives a vigorous
puff when ignited in a vessel; five volumes of air to one of vapor gives
a loud report. The maximum degree of violence results from the explosion
of eight or nine parts of air mixed with vapor. It requires considerable
skill to make at will an explosive mixture with air and naphtha, and it
is consequently very easy for the vender not to make one. In most cases
the proportion of vapor is too great, and on bringing a flame in contact
with the mixture it burns quietly. The vender, to make his oil appear
non-explosive, unscrews the wick-tube and applies a match, when the
vapor in the lamp quietly takes fire and burns without explosion. Or he
pours some of the 'safety oil' into a saucer and lights it. There is no
explosion, and ignorant persons, biased by the saving of a few cents
per gallon, purchase the most dangerous oils in the market. It is not
possible to make gasoline, naphtha, or benzine safe by any addition that
can be made to it. Nor is any oil safe that can be set on fire at the
ordinary temperature of the air. Nothing but the most stringent laws,
making it a State prison offense to mix naphtha and illuminating oil, or
to sell any product of petroleum as an illuminating oil or fluid to be
used in lamps, or to be burned, except in air gas machines, that will
evolve an inflammable vapor below 100 degrees, or better, 120 degrees
Fahrenheit, will be effectual in remedying the evil. In case of an
accident from the sale of oil below the standard, the seller should be
compelled to pay all damages to property, and, if a life is sacrificed,
should be punished for manslaughter. It should be made extremely
hazardous to sell such oils." Prof Chandler is professor of analytical
chemistry, School of Mines, Columbia College.
There is no substance on earth, or under the earth, which will
chemically combine with naphtha, or that will destroy its peculiar
volatile and explosive properties. The manufacturers of petroleum
products have exhausted the whole resources of chemistry to make this
product available as a safe burning oil, and their inability to do so
proclaims the fact that it cannot be done. Chemistry has shown that
naphtha, and, in fact, the other products of petroleum, will not part
with their hydrogen or change the nature of their compounds, except by
decomposition from a union with oxygen, that is, by combustion. These
humbugs, who deceive people for their own gains, may put camphor, salt,
alum, potatoes, etc., into naphtha, and call it by whatever fancy name
they please. The camphor is dissolved, the salt partially; potatoes have
no effect whatever. The camphor may disguise the smell of the naphtha,
and sometimes myrhane or burnt almonds may be used for the same purpose.
But, no matter what is used, the liability to explosion is not lessened
in any degree. The stuff is always dangerous and always will be. There
is not much danger in the use of kerosene, if it is of the standard
required by law in several of the States. At the same time petroleum is
dangerous under certain conditions. Where oil is heated it is more or
less inflammable, and, in fact, inflammability is only a question of
temperature of the oil, after all. Burning oils should be kept in a
moderately cool place, and always with care. Of course, if a lighted
lamp is dropped and broken, the oil is liable to take fire, though the
lamp may be put out in the fall, or the light drowned by the oil, or the
oil not take fire at all. This will be the effect if the oil is cool and
of high flash test. When a lamp is lighted, and remains burning for some
time, it should never be turned down and set aside. The theory is, that
while lighting, a certain supply of gas is created from the oil, and
that when the wick is turned down that supply still continues to flow
out, and not being consumed, forms an inflammable gas in the chimney,
which will explode when a sufficient quantity of air is mixed with it
in the presence of light, which may happen if a person blows down the
chimney; but a lamp should never be extinguished in that way. A good,
high test kerosene oil can be made with ordinary care as safe as sperm
oil, though, of course, it is not so safe as a matter of fact. We are
sure to hear of it when an accident happens, but we never hear of the
reckless use of kerosene where an accident does not occur, and yet
there are few things so generally carelessly handled as burning
oils.--_Fireman's Journal_
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