DIRECT OIL FIRING use of oil for the production of power was first initiated in Russia and originated in the brain of a mechanic employed in the first refinery in that country. In those early days, when the market for oil was of a very restricted character, the intermediate oils were practically the only descriptions produced, the heavy residues and the very light oils being discarded as waste. On the suggestion of this man the question of burning the heavier oils as fuel was taken up and the first oil burner was invented by him in 1861. He adopted various contrivances, but ultimately settled on an apparatus consisting of a series of grates or griddles, over which the liquid trickled and burnt. A patent was taken out by him for this device in 1867 and many firms used it, but gave it up when improved appliances were available.
In 1962 attention was directed in America towards the application of petroleum for heating and power. Another early method of burning the oil was by means of a pan or step over which the oil flowed and was ignited, while almost at the same time Shaw and Linton patented in America a furnace in which the fuel was conveyed into the interior in a gaseous state, the oil being previously heated and made to give off its lighter oils, which were subsequently consumed inside the fur nace. Undoubtedly, this was a more advanced idea than that of burning the oil in its natural state openly in the bottom of the hearth. In the year following (1f363) the first spray furnace was introduced into America by a Mr. Brydges Adams for use on locomotives ; yet, in spite of this great improvement and the most perfect combustion of the fuel obtained, a year later Richardson introduced into England what was known as an oozing furnace. In this furnace, which was experimented with by the inventor in conjunction with the Admiralty, the bottom was lined with ordinary burned slack lime, spread evenly at the top, but with a number of small vaultings at the bottom of the layer. The oil entered these spaces from tanks, and pene trating the lime, which acted as a sort of wick, became ignited and was consumed. Later experiments were made with this method of burning the oil, with the result that a commission appointed by the Admiralty reported very favourably thereon, though the system was not adopted, owing to the prohibitive price of liquid fuel.
The experiments, however, served to show that unmixed oils had a greater evaporative power than mixed, the latter in this case consisting of tar oil and shale oil, and, in one instance, tar, shale, and American crude oils.
It is unnecessary to enter into more detail in regard to the early development of the oil fuel burner, as the instances given lead us to the stage where the main lines have been laid which led up to the evolution of the present types of burner. The year 1883, however, marked the opening of a new era, initiated by the invention of Sir (then Mr.) James Holden, of the burner known by his name. As Locomotive Superintendent of the Great Eastern Railway he turned his attention to the use of liquid fuel for steam raising for locomotives, with the object of using the waste tar obtained from the oil gas works at Stratford. His purpose was to devise one which would be independent of any extra brickwork, and also should be available for use in conjunction with coal, and he ultimately introduced a system by which it became possible to fire a boiler either with coal alone, as ordinarily used, with coal and oil combined, or with oil alone.
In the early days of oil-firing experience, Mr. Holden discovered that ordinary jet burners could not be relied on to spray efficiently enough oil for the generation of sufficient steam without the brick arrangements objected to, and a new burner was therefore devised which included many improvements.
The chief methods adopted in burning oil under boilers are : mixing oil with a steam jet and heating and atomizing it by means of a burner of small design through which the oil is forced, under low pressure, by the use of a pump or by gravitation from a settling tank ; compressed air burners, which act on the same principle but which involve the use of air compressors, thus rendering the installation somewhat complicated and expensive and reducing reliability ; and the pressure jet system, which eliminates the necessity of using either steam or compressed air for atomizing the fuel.