Coal oil

“ From the incineration of wood to the use of peat and coal would prove an easy stage in the advance toward present day practices, and with the attainment of coal as a fuel the first great era in man's fire-making habits may be said to end.
Beyond the coal stage, however, lies the more or less distinctively modern one of the utilization of gas and oil for fuel. The existence of great natural centers, or underground stores, of gas and oil is probably no new fact. ”

“ The advantages claimed for oil over coal as fuel are many. It is smokeless, produces more heat than coal, occupies less space for storage, can be loaded more quickly and easily, is cleaner, and reduces the engine-room force to one-fourth or one-third the number of men required when coal is used. ”

“ In the direct distillation of cannel-coal for the production of paraffin, it is necessary that the perpendicular tubes or retorts into which the coal is placed be heated only to a certain temperature, which is considerably lower than that applied when the object is the production of coal-gas. By this means nearly all the volatile matters pass over in the form of condensible vapours, and the crude oils are at once formed, from whence are obtained at different temperatures various volatile ethers, benzene, and artificial turpentine oil or petroleum spirit. ”

“ Evaporation by the sun was at one time the sole means of obtaining salt from seawater; now coal is used to boil the salt pans and to purify the brine from the salt-mines in the triassic strata of Cheshire. The extent to which gas is used for illuminating purposes reminds us of another important product obtained from coal. Paraffin oil and petroleum we obtain from coal, whilst candles, oils, dyes, lubricants, and many other useful articles go to attest the importance of the underground stores of that mineral which has well and deservedly been termed the "black diamond." ”

“ Ten per cent of the coal should be cannel; naphtha is, however, often employed to subserve the same purpose, one ton of ordinary bituminous coal requiring four gallons of oil.
In Boston, 7,000,000 cubic feet of gas have been burned in one day, consuming 500 tons of coal; the average is not more than half that quantity. Of the other products, coke is employed for heating purposes, gas carbon is used to some extent in electrical work, and coal-tar is the source of very many artificial products that were formerly only of natural origin. ”

“ The illuminating power of carburetted hydrogen obtained from coal tar when compared to the gas obtained from the best Newcastle coal is in the proportion as six to five. In fact the intensity of light evolved during the combustion of gazeous bodies composed of carbon, hydrogen, and oxigen, is always in the ratio of the quantity of carbon contained in equal quantities of the gazeous compound, and hence the gas from animal oil which is chiefly composed of supercarburetted hydrogen or olifiant gas, surpasses in illuminating power the gas obtained from coal. ”

“ Oils are also artificially produced from the so-called waste-products of the gas-works, but in some parts of the world the process of their manufacture has gone on naturally, and a yearly increasing quantity is being utilised. In England oil has been pumped up from the carboniferous strata of Coalbrook Dale, whilst in Sussex it has been found in smaller quantities, where, in all probability, it has had its origin in the lignitic beds of the Wealden strata. Immense quantities are used for fuel by the Russian steamers on the Caspian Sea, the Baku petroleum wells being a most valuable possession. ”

“ Ton for ton, petroleum has every advantage over coal, and there is every reason why it should drive coal out of its preeminent position in industry, except one—the limitations of the supply.
For petroleum is far cheaper to produce, not only in terms of money, but in terms of human effort and life. Compare with the labor and hazard of opening and working a coal mine Pogue and Gilbert's description of the opening of an oil well. ”

“ This, of course, is more fraught with danger to the coal master than to gas companies, inasmuch as, should this prove to be a more economical raw material from which to produce illuminating gas than coal, our present coal gas works could be easily remodeled and turned into oil gas works. ”

“ J. and P. Taylor [57] are the first persons who have resorted to oil as a substance from which gas for illumination could be easily and cheaply prepared; and in the construction of a convenient apparatus for the decomposition of this body, they have fully shewn its numerous advantages over coal, while they have afforded the means of producing the most pure and brilliant flame from the inferior and cheap oils, which could not be used in lamps. The apparatus for the purpose is much smaller, much simpler, and yet equally effectual, with the best coal gas apparatus. ”

“ Peat is said by geologists to be only "coal in the making," carbon that is in the state of changing from vegetable matter to coal. It is probable that in the course of centuries this would become coal, and in its present state it has many of the properties of coal, though it has not nearly so high a heating value.
In this country we have had such a wealth of fuel resources—coal, wood, oil, and gas—that up to the present time we have done little to develop our peat beds, although in European countries ten million tons are used annually for fuel, as well as large quantities for other purposes. ”

“ But as the gas is at present supposed to be the only object in view, for the sake of the light which it yields, the other products being only accidentally connected with its extraction, let us leave the idea of profit on them out of the question, and with the utmost latitude of concession, require them only to stand as in part for a portion of the coal employed in the process, we have still the gas, an article which performs the functions of the oil, the tallow, or the wax for which it is substituted ”

“ After the mixture, the gases must be screened from the light, otherwise the common carburetted hydrogen would also combine with the chlorine, while water and carbonic acid would make their appearance.
The oil employed for affording gas is the crudest and cheapest that can be bought; even the blubber and sediment of whale oil are employed with advantage. After all, however, coal is so much cheaper, and the gas produced from it is now so well purified, that oil and rosin are very little used in gas apparatus. ”

“ The gradually increasing amount of heat which we meet the deeper we go beneath the surface, has been the cause of a slow and continuous distillation, whilst the oil so distilled has found its way to the surface in the shape of mineral-oil springs, or has accumulated in troughs in the strata, ready for use, to be drawn up when a well has been sunk into it.
The plants which have gone to make up the coal are not at once apparent to the naked eye. ”

“ I am writing by a hard coal fire in a round oak stove, and it makes a splendid heat. Better soft coal than you ever burned can be had at $9.50 per ton, and hard coal is $13. Wood is plentiful in the parks, chiefly dry poplar and a species of willow.
"So far from town one needs big supplies of kerosene, so bring a steel barrel that will not become leaky. You can buy oil cheaper by the barrel and it saves trouble. Also bring a good oil stove. It will do the baking and save hauling fuel in the long working season. ”

“ It could, nevertheless, be made to yield gasoline, fuel oil, and other products if suitably processed.
The shale strata generally the richest in oil are found above coal seams, are black, and are sometimes called slate by coal miners. They are rarely more than 3 feet thick, but they extend over large areas. ”

“ Consequently, to make it carry any further quantity in a condition not easily deposited, the oil would have to be completely decomposed into permanent gases, and the temperature necessary to do this would seriously affect the quality of the gas given off by the coal. When, however, the distillation has gone on for three hours, the rich portions of coal have distilled off and the temperature of the retort has reached its highest point, and this is the best time to feed in the oil. ”

“ There are, of course, many reasons which have commended fuel oil to the experts as a substitute for coal. In the first place, inasmuch as one ton of fuel oil is equal to more than one-and-a-half tons of coal, the radius of action of units fitted for utilizing fuel oil is increased over 50 per cent.—I speak from the point of view of bunker weight. Again, one ton of oil occupies considerably less space than an equivalent weight of coal, while this advantage can be materially increased—as is now the usual practice—by carrying the fuel oil in double-bottom tanks. ”

“ The sp. gr. of oil-gas varies with the heat employed in its production. It averages from 0·76 to 0·90, but it may rise as high as 1·1.
The composition of coal gas, as given by Payen, is as follows:—
OILS (Drying) . All the fixed oils have an attraction more or less powerful for oxygen, and, by exposure to the air, they either become1120 hard and resinous, or they only thicken slightly, and become sour and rancid. Those which exhibit the first property in a marked degree, as the oils of linseed, poppy, rape, and walnut, are called ‘drying oils,’ and are used as vehicles for colours in painting. ”

“ Marsh gases often occur in great quantities in faulted zones in the coal measures, though the bituminous substances found in coal are not true bitumens that dissolve in the usual solvents, while the tars derived from the destructive distillation of coal in no way resemble natural petroleums or the products of oil-shale distillation. ”

“ The gas created by the process can be delivered by pipe lines over practically any distance to the centers of consumption, or, with the help of the internal-combustion engine, converted into electrical energy at the mine. Gas as a fuel has the great advantage that it eliminates both storage and haulage, and produces the same amount of heat from about one-half the amount of coal, and since it can be produced as needed all the year round it will go far to eliminate the seasonal character of coal mining. ”

“ This is not yet eighty years ago, and amongst the many wonderful things which have sprung up during the present century, perhaps we may place in the foremost rank for actual utility, the gas extracted from coal, conveyed as it is through miles upon miles of underground pipes into the very homes of the people, and constituting now almost as much a necessity of a comfortable existence as water itself. ”

“ The chemical changes which have taken place in the beds of vegetation of the carboniferous epoch, and which have transformed it into coal, are even now but imperfectly understood. All we know is that, under certain circumstances, one kind of coal is formed, whilst under other conditions, other kinds have resulted; whilst in some cases the processes have resulted in the preparation of large quantities of mineral oils, such as naphtha and petroleum. ”

“ And if we give credit to the assertion of those workmen, whose business it is to manufacture a given quantity of gas by means of a certain quantity of coal delivered to them, it would appear that coal which affords gas abounding in sulphuretted hydrogen, is the kind of coal most easily to be decomposed. This, as far as it regards the decomposition of Scotch Splent or cannel coal, is certainly true. No species of coal affords gas at a lower temperature, and of none is the gaseous product more loaded with sulphuretted hydrogen gas. ”

“ The gas which soon comes from the stem of the pipe does not take fire unless a light be applied, when it may be seen to burn with a bright flame, and after the flow of gas has ceased, nearly the whole of the carbon of the coal will be found unconsumed in the bowl of the pipe. This simple experiment illustrates perfectly the first step in the manufacture of coal-gas, namely, the process of heating coal to redness in closed vessels, by which operation the substances originally contained in coal are destroyed, and their elements enter into new combinations. ”

“ The coal measures are due to the storing under water of semi-aquatic plants which have been preserved by being silted up, and we know that coal is full of olefiant gas, marsh-gas, sulphuretted hydrogen and carbon monoxide, which are all combustible, and that the carbonaceous residue, charged with volatile and combustible hydrocarbons, forms the chief fuel of the civilised world. Peat is formed in ways analogous to that of coal, and the so-called mineral oils are certainly the products of organic matter which has been silted up. ”

“ For more than two years the Government has been conducting a series of experiments in a very thorough manner, endeavoring to ascertain the gas values of the great lignite coal fields between Boulder and Denver. It has been discovered that the converting of the coal into gas gives it double the efficiency for use as a motor power for engine or for fuel than can be gained from the coal in its natural state. ”

“ As we must deduct from the coke that quantity which is required for the heating of the retorts, and which, even when good gas producers are employed, amounts to 12% of the weight of the coal, or 10% of its heat value, the total loss of heat rises to 27%. Taking, further, into account the cost of labour, the wear and tear, and the capital interest on the plant, coal gas must always be an expensive fuel in comparison with coal itself, and cannot be thought of as a general substitute for the latter. ”