Powdered Coal for Fuel.

Huntly Press and District Gazette, Volume 3, 13 November 1914, Page 3

Powdered Coal for Fuel.

That a saving of 50 to 60 per cent, over other fuels may be effected by' using powdered coal in industrial furnaces is asserted in The American Machinist (New York), by E. A. Suverkrop. He bases this statement on statistics furnished by the American Locomotive Company, at whose Schenectady works a coal-mil-ling and distributing plant capable of handling five tons an hour is in sucessful operation. The use of powdered coal as fuel, Mr Suverkrop notes at the outset, has been known for sixty years, but in the early days little success was met in handling it, and large sums of money were spent in research work. The principal cause of failure

was the use of high pressures, which produced a sand-blasting effect, cutting the furnace linings so badly that their life was only two weeks. But early difficulties have been overcome. “ The first really sucessful system of burning powdered coal j>in metallurgical furnaces was in the plant of the American Iron and Steel Company. They mastered the basic principles and evolved a device to control the fuel. This was more than ten years ago, and ypey now have about eighty furnaces in one of their plants. “ The cost of fuels is dependent upon a number of factors, such, as location and quantities used. The work to be done must also he taken into consideration, and no one fuel will be found the best under all circumstances. However, where the consumption great enough to warrant the installation of an equipment for handling, milling, distributing, and burning, pulverised coal will effect great savings. “To give the best results, powdered coal must be dry, that is to say, it must not contain over \A per cent, of moisture. Dry coal also requires less power to pulverise it. It must be definitely divided: from 93 to 95 per cent, should pass a 100-mesh sieve, or 80 to 85 percent, a 200mesh sieve,. When in tins state in a proper burning apparatus, each particle is surrounded by the necessary amount of air for combustion, and the entire energy of the fuel is liberated at once. The volatile gases ignite, i and the fixed carbon is consumed instantly when the fuel enters i the combustion chamber. “ The flame from powdered coal > resembles that obtained with I either oil or gas, and it can be ; regulated by increasing or decreasing the air or fuel supplies by opening or closing the valves • governing them. The fire is under absolute control . . .and the entire inflammable portion of the coal is converted into r heat.” ; The present plant ctSchenectadv replaced one for the use of fuel-oil about two years ago. i “Thefir.es are usually started r with oily waste or wood in front . of the burner, much in the same 5 way that oil or gas fires are . kindled. The cost of installation , is less than that for producerr gas. High temperature can be , obtained without regeneration, and the loss in gasifying is , eliminated. The writer gives the number , of British thermal units yielded j by an expenditure of one cent. , with powered coal as 114.036 as ] compared with 27,282 for fuel-oil and 91,228 for producer gas. At .! the Schenectady plant the cost of operation is said to he only 48 1 per cent, of that with oil —a saving of more than one-half.