COAL RESEARCH

New Zealand Herald, Volume LXXII, Issue 22006, 12 January 1935, Page 7 (Supplement)

COAL RESEARCH

NEW METHODS IN THE TRADE A visit to the Fuel Research Station near Greenwich gives one an added respect for coal, for research workers, and for all that coal implies. But it also makes one realise the wastefulness of the methods still in general use of applying the benefits of coal to the human race, writes the Herald's London correspondent. The Fuel Research Board maintains nine laboratories on the coalfields of England for the purpose of a national coal survey. Hitherto coal has been taken from the pits and sold on a very rough assessment of quality. Now that has changed, and both colliery owners and purchasers have a more intimate knowledge of quality and heat producing properties. The object of the coal survey is to examine the coal seams as they occur below the ground, tracing the variations in properties from floor to roof and from place to place. Pillars of coal containing sections of the seam from top to bottom are taken intact for examination, and it is interesting to learn that in such a pillar the quality of the coal may vary very greatly. The laboratory examination has, in some cases, indicated how the coal can be improved by modifying the method of working the seam in the mine. It provides information as to the correlation of the coal seams in different areas, a problem which is frequently of considerable practical importance. It indicates where coal possessing > particular properties can be obtained and suggests means of improving the quality of the coal for a particular purpose by cleaning or blending. The board has the satisfaction of knowing that the colliery owners make use of the information gained, not only in the utilisation of the coal, but in deciding questions as to the desirability of opening up or closing down certain seams. Formerly large lump coal selected by hand at the picking belts was in great demand because it contained the least ash and was relatively easy to handle. Great strides have, however, been made in the purification and grading of small sizes of coal, and now over 77 million tons of coal are cleaned every year in England either by washing or dry-cleaning processes. This is a very large proportion of the small coal raised. The result is that there is now less demand for large coal and an increased demand for small coal. This change in public demand, which applies both to domestic and industrial requirements at Home as well as to export coal, has been fostered by a number ot factors. Among these are the increase in the mechanically-fired furnaces as compared with, hand-fired, the utilisation of graded, small coal by the gas industry, and the diminished storage accommodation in the modern house or flat, together with the advantages associated with the sale of coal in bags. The householder is 110 longer favouring large coal; he finds it preferable to buy the coal in suitable sizes, and thus avoid not only the trouble of breaking it up, but the consequent wastage due to the formation of coal dust. The change in the demand for large and graded coal has come somewhat rapidly and is being felt in several oi the coalfields. The result is that a new problem has arisen—how to break down the large coal to the sizes most in demand without the undue formation of dust.