Substitutes for Coal.
In the present dearth of coal, it is satisfactory to know that efforts are being made in various directions to meet the public wants in the way of fuel. We have heard good deal lately of processes for the utilisation of peat —a substance which commends itself once in respect of its abundance, and of its richness in burning material. It has been generally felt that if the substance forming our vast moors could be converted into a fuel equal or nearly equal to coal, the question which has been causing so much anxiety to householders and manufacturers would be practically solved, while a new source of wealth would be opened up in districts hitherto comparatively unproductive. The difficulty to be overcome in the first instance was to devise a method of preparation which should give the peat the necessary solidity and heating power.
Among those who have turned attention to the subject is the Duke of Sutherland, a nobleman whose intelligent interest in all schemes of improvement adds additional lustre to his rank, and who, of course, is fully alive to the importance of any enterprise which promises indefinitely to enhance the value of moorland property. For some time past the Duke has been experimenting, with more or less success, in the preparation of peat by compression.
Latterly, however, his Grace has become connected with an undertaking which, by means of a more elaborate process, aims at the conversion of peat and coal waste into a fuel capable of meeting all requirements. We refer to a patent recently taken out by Mr Pender, M.P., for set of machinery contrived, we believe, by his factor, Mr Rae, with reference to system of fuel manufacture which presents some features novelty. For the working of this patent, a company is in course of formation, with the Duke of Sutherland at its head, and operations are about to be commenced at Seafield, near Bathgate, where, as well as in the adjacent property of Blackburn, leases of coal, shale, and peat have been obtained from Mr Pender.
The process in question is adapted for the production of two, it may be three or four varieties of fuel, the materials employed being coal dust, peat, crude shale oil and shale tar, or other similar substance. One compound proposed to be made is that of coal dust and tar; another will consist of peat and tar, with a certain admixture of oil. Or the coal dust fuel may be mixed with oil with a view to the production of gas-making material, or, again, it may be found desirable to mix coal-dust and peat in certain proportions. important feature of the process is the mode of preparation the tar, for which a portion of the machinery designed Mr Rae is specially appropriated. The tar is first steamed and washed with lime water, so as to extract any acid it may contain, after which, by the removal of a certain portion of oil, it is reduced to the condition of a mastic, or something of a consistency between tar and pitch. In this state it can be used in smaller quantity, and gives to the fuel made with it a toughness and solidity not to be attained by the use of pitchy substance.
Other portions of the machinery provide for the crushing of coal and the maceration of peat, the thorough drying those substances after having been so dealt with, and the subsequent mixing of them with tar or oil. The compound thus formed is next subjected to pressure, and having been cut into blocks, is delivered in that state upon a creeper or endless web, by which it is carried away from the machine, and by which, if thought necessary, it may be carried through a furnace and subjected to a process of roasting, with the view of rendering the surface impervious to atmospheric influences.
The fuel produced in this way has, we are told, been subjected to variety of tests, and with such results as seem to augur well for its general adoption. In regard to its capability for standing exposure to the weather, it appears that a quantity made at Dunrobin lay uncovered during the whole of last winter without deterioration. The question whether it is equally adapted to resist disintegration by heat is now being put to the test of experiment. The coal dust fuel, which consists of coal and tar in the proportion of 93 to 7, is found to be so compact that something like 90 tons can be stowed in the space occupied by about 50 tons of coal. In regard to other qualities, it has been tested the Admiralty at Portsmouth Dockyard, with satisfactory results ; and trial has also been made of it in railways and steamboats. Among other recommendations, it turns out to be particularly well adapted for the rapid raising of steam. Then again the amount of ash produced is so trifling that very little stocking is required ; and as for heating power, practical men will understand the value of a fuel which claims to have evaporated 9| lb. of water for each pound consumed. The peat fuel, which, in addition to tar, contains from 5 to per cent, of oil, has come out equally well in experimental trials. Whereas the condensed peat prepared at Dunrobin could only be got to evaporate lb. of water per pound consumed, the peat fuel produced by the process just described was found, when tested the Duke's railway, to have an evaporating power of lb.
One point which remains to be proved regard to this material whether it can be made of sufficient density to stand the heavy draught of locomotive engines. this respect the machinery now in course of erection is expected to realise all that can be required. In addition to the other advantages above specified, the new fuel claims the important merit of cheapness. With the present price of coal dust, it is expected that the fuel made from it may be offered to the public at something like 9s a ton. In the case of peat a cheaper raw material will render it possible to sell the manufactured article about 7s a ton. Such least are the prices spoken of as probable, and it seems clear enough that even higher rates a material offering anything like the advantages speeitied must command ready market. Besides the works in Linlithgowshire to which reference has been made, it is, believe, intended to prosecute the manufacture on the
Duke Sutherland's property at Brora. In that quarter there is peat ad libitum, together with plenty of shale and coal. The shale, of which two thick seams have been proved, is found to yield a very high percentage of oil, and that of a density which renders it peculiarly suitable for the production of tar. The coal was worked as early as Queen Elizabeth's time, but has been entirely neglected for the last fifty or sixty years. Now, however, there seems every probability of that, well as the other mineral wealth of the district, being turned to profitable account.— Scotsman.
The Falkirk Herald, 24th April 1873