Petroleum

by Albert Lidgett

As I have mentioned in another chapter, enormous quantities of natural gas exude from the oil-wells, and this in the past has been for the most part allowed to go to waste in the air, causing an ever-present danger to oil-field operations on account of its liability to ignite. Being heavier than the air itself, for it is impregnated with oil gases, it remains for long periods in the lower air strata, and, consequently, not infrequently, has been the direct cause of great oil-field fires. This gas—casing-head gas, as it is termed—comes from the oil-wells between the casing and the tubing, and, in the case of numerous wells, the flow is remarkable, some wells giving forth 300,000 cubic feet of gas every 24 hours, and the only useful purpose that this vapour has served until recent years has been to light several towns situated comparatively near to the oil-producing fields. The great volume of the gas, however, has been allowed to go to waste.

But experiments have proved that the gas is capable of condensation into motor spirit, and the general yield of such spirit may be taken as fully 2 gallons per 1,000 cubic feet of natural gas treated. What wonderful possibilities lie in the direction of the conversion of this vapour into motor spirit! The oil-producers in the United States have not been slow to appreciate this, and to-day there are hundreds of plants in the United States which have been erected solely to condense these oil-well gas vapours. Some of these plants are dealing with as much as 3,000,000 cubic feet of gas a day. The most recent official returns available from the United States show that the production of gasoline (motor spirit) from this process of oil gas condensation is, approximately, 150,000,000 gallons per annum, and even this substantial figure is being steadily increased.

There is also another phase of the oil-refining industry which, during recent years, has materially altered. I refer to the production of solar oil during distillation. It is an apt saying that we can scarcely look to any section of our commercial or domestic life without being confronted with the fact that oil products play some part therein: there are few, however, who, without reflection, would agree that when they light their gas they are dependent upon petroleum for much of the light the gas gives. It is, nevertheless, a fact, as I will proceed to show.

Many years ago, the oil refiners in Baku were confronted with a problem which appeared for some time to be insurmountable. After the distillation of their kerosene, or illuminating oil, and before they could commence to take off the lubricating oil fractions, there was an intermediary product which, while being of no use for lamp oil, did not possess the necessary constituents of viscosity to make it acceptable as a lubricant. It was a fairly decent volume of something for which there was no market at the time.

Experiments were made, and with these the name of Dr. Paul Dvorkovitz will ever be associated, and it was found that by the passage of a current of gas over the surface of this intermediate product, the gas caught up as it were a richness which materially increased the lighting power of the gas. To cut a long, but highly interesting, story short, this solar or gas oil was subsequently introduced by Dr. Dvorkovitz to England for gas enrichment purposes, and the extent of its employment to-day may be judged from the fact that the United Kingdom regularly imports between 60,000,000 and 70,000,000 gallons per annum for the enrichment of the coal gas which finds useful employment in practically every home throughout the land. As is known, the gas companies have to produce gas of a certain lighting quality, and it is in the upholding of the lighting strength of the gas that solar oil to-day plays so important a part. At first, the oil came almost exclusively from Russia, but now the competition from the United States has secured for our American friends the vast bulk of the trade, which, as I have shown, has reached enormous proportions.

Solar oil is also largely utilized for the production of refined perfumery oils, which are quite colourless and inodorous, while the finest quality is used in pharmacy and known as paraffinum liquidum, and is in much demand, but in this connection it is the Russian petroleums that have gained distinction. It was held for many years that such tasteless and colourless oils could not be produced from the United States petroleums, but from the commencement of the European War, and the consequent closure of Russia’s export port, whereby all overseas trade in Russian petroleums was held up, much progress was made in the manufacture of tasteless medicinal petroleums in the United States, such articles having now become popular throughout the world.

One of the most important discoveries made during recent years has been the finding of large quantities of toluol in petroleum. This article is necessary for the manufacture of high explosives. In Borneo heavy petroleum, toluol exists to a very large extent, and it was its discovery and consequent use by the allies—thanks to the offer made to the Governments by Sir Marcus Samuel, Bart.—that almost unlimited quantities of high explosives were manufactured.

Vaseline is another useful commodity which is derived from the refining of crude petroleum, and this article is turned out of the American refineries as well as those of Russia and Galicia, in large quantities, but, beyond mentioning this fact, no useful purpose would here be served by relating the various processes employed.

With reference to the methods generally adopted in the refining of the products from the distillation of the Scottish oil shales, these are briefly dealt with in the chapter devoted to the Scottish oil industry.

It is safe to say that the past two or three decades have witnessed marked progress in perfecting the methods by which crude petroleums are refined into the innumerable common commodities of commerce, and it is doubtful whether in any branch of chemical research there has been such concerted energy shown as in regard to the refining of mineral oils. Signs, however, are not wanting to show that the zenith of this progress has by no means been reached.