PETR OLEUM OILS.
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 practised 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 canbe 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 parrafine 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 naptha, 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 test.
An oil that will stand 100 flash will stand no burningtest 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 too degrees Fahrenheit, such an oil w’ould be safe. It would produce no vapors to mi* 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 fifleen 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 burningtest 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 naptha. 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 ‘nonexplosive ’ 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 offence 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 deg., or better, 120 deg. 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.