Co a l A ge Established 1911 — McGraw-Hill Publishing Company, Inc, DEVOTED TO THE OPERATING, TECHNICAL AND BUSINESS PROBLEMS OF THE COAL-MINING INDUSTRY SYDNEY A. HALE, Editor New York, July, 1935 ♦ Vacuum Cleaning Miners can avoid many such accidents by going slow, but they either do not take this precau­ I n a W estern mine, men used to be sent tion or, taking it, become less efficient. along the haulageways at night to sweep the At the face, bad lighting slows operation and- tops of the crossbars to remov e dangerous dust, makes it impossible to clean coal effectively. thereby doing little but throwing it down to Here, even time and pains will not make alight on ribs and floor. By working with the amends for inefficient lighting. W ith coal inef­ air current, the dust could be dislodged a second fectively cleaned, the cars are loaded with dirt, or third time if it settled on other crossbars, which decreases transportation efficiency and and thus in the end all were clean. It was not makes the use of more cars, locomotives and a safe operation with open lights nor an effi­ transportation men inevitable. Arriving at the cient one. A motor and vacuum cleaner on a surface, the coal requires more men on the pick­ truck would have cleaned the timbers more ing table to remove the dirt that should have effectively and rapidly, but in those days vac­ been thrown away by the miner. He may be uum cleaners had not been invented. docked for dirty coal, causing labor discontent Today, vacuum cleaners could be adapted to and possible trouble. If he is not, then the com­ the work and to clean ribs, and even the floor, pany has to stand the loss for the labor of especially in places where fine dust is swept off cleaning, the disposal of the reject and, even the cars or is formed and swept by the current more important, the mining of the dirt. in dumping coal for hoisting by skids and belts. Bad lighting hinders and renders imperfect In dumping, of course, nothing is better than a the work of others than miners. In fact, it current of air to take the dust from the mine takes toll at every point of the operation— and to the surface. Where possible, this should be especially in compensation, cutting, loading, provided, though here again it will lodge on transportation, preparation, equipment, ton­ timbers and buntons in the slope or shaft by nage, administration and regularity of opera­ which the surface is approached, establishing a tion, and does it in such insidious ways that the hazard. losses are not readily apprehended— but a care­ ful analysis will suggest the magnitude of these hidden costs. Toll of Darkness Though bad lighting is the basal cause Hardly Helpful of most accidents, they are invariably credited to more obvious hazards. Bad lighting makes A m e n d m e n t s embodied in the revised it difficult to note roof and coal defects that Guffey-Snyder bill, reintroduced in Congress may cause falls of both. Falls of persons last month, hardly can be expected to bring largely come from bad lighting and such falls opponents of that particular proposal for bitu­ often cause accidents listed as transportation minous control into camp. Aside from making casualties. In coupling cars darkness is a fre­ the allocation provision a mandate for further quent hazard and in the darkness the men on study instead of an order for immediate action, the cars are exposed to the risk of low roof. few of the major objections to the original ferrous sulphate in its formation is not certain, draft appear to have been eliminated. Indeed, but assuming seven molecules, the volume of some of the modifications incorporated into the the ferrous sulphate crystal will be 6.1 times new version will only provoke fresh attack and as great as the volume of the pyrite from widen the breach already made in the industry which it is formed. Larger crystals of pyrite over this bill. Provision for excluding the ten per cent of may be acted on only at their surface, but the the tonnage in each district “represented by the microscopic kinds would respond to oxidation highest cost mine production” from minimum in their entirety. Consequently the coal is com­ price calculations has disappeared in the re­ pressed all over its mass by the expansion of drafting. In its place is a “minimum-price- particles of pyrite. This involves not only area” scheme which would place all the Appa­ chemical but physical action, which in turn lachian region except three counties in Tennes­ opens up the coal to the adsorption of oxygen see, Michigan, Illinois, Indiana, western Ken­ and carbon dioxide, which are both heat-creat­ tucky and Iowa into one group and split the ing actions. If pyrite also acts as a catalyst in remaining producing districts into eight “mini- the oxidation of coal and in other physical mum-price areas.” Ostensibly offered as a solu­ changes it will be easy to accept the idea for­ tion to the vexatious problem of price correla­ merly so prevalent that pyrite is the main cause tion, the new scheme is so confused and contra­ of spontaneous combustion. dictory in its terms that it cries aloud for clari­ fication. Storage Helps Anthracite Title II, creating a national reserve with the use of government credit to purchase marginal T e s t s have shown that stored anthracite coal lands— a grandiose plan which the May- has a greater heat value than fresh coals, but end conferences of operators had suggested such analyses are subject to error and the fresh- should be deferred for further study— reap­ mined anthracite might not be representative pears in the revised bill in all its monopolistic of the coal put in storage; so some question the vulnerability. The recommendation that the value of such indications. However, a few control system set up expire by statutory limi­ years’ exposure to weather should improve an­ tation at the end of four years is ignored in thracite, oxidize its pyrite and wash most of the the Guffey-Neely redraft and loosely handled products away and remove also not a little lime in the Snyder revision. Unilaterality still char­ and magnesia. acterizes the labor provisions of the bill, with Granting that the proportion of pyritic sul­ freedom from strikes dependent upon the will phur is 0.5 per cent, the pyrite content will be and the graciousness of organized labor. 0.93 and possibly 1 per cent, for the other im­ Legislation to prevent a return to the chaotic purities associated with the pyrite will come and degrading conditions of a few years ago is with it. Its heat in burning would be 20 highly desirable. The Guffey-Snyder bill B.t.u. per pound of coal. W ith coal of 13,000 should be a convenient framework upon which B.t.u. the thermal value of the 99 per cent of to build such legislation. But simply because the product remaining after pyrite oxidation the need is so pressing, however, is no reason will be 12,980 B.t.u. Hence, a full pound of why anything less than legislation soundly con­ coal will have 13,111 B.t.u. ceived and equitable in its terms should be The solution of lime and magnesium sul­ jammed through. Shotgun weddings which phates would still further decrease the volume impose a galling yoke can lead only to strife of coal without decreasing its heating value, and disaster. but some gas is lost which has a heat value greater than that of the coal, weight for weight; but this loss, though not determined, is Role of Pyrite unfortunate, more because it makes the coal C h e m is ts say that the seat of formation slow to ignite than because it reduces its heat­ of ferrous sulphate from pyrite is not enough ing quality. However, the loss of the iron of to explain the spontaneous ignition of coal, but pyrite decreases the clinkering tendency of the they overlook the important physical effects coal, so while appearance and response to igni­ which accompany that transformation. Just tion decline, the actual heat value increases and what the quantity of water would combine with clinkering troubles decrease when coal is stored. 282 COAL AGE — Vol.40, No.7 ANTHRACITE ELECTRIFICATION + Shows Increase of Synchronous Drives And Adoption of Lighter Power Cables By J. H . E D W A R D S Associate Editor, Coal Age VEN without consideration of the moment consider installing converters. E number of substations operated by Apparently this widespread use of synchronous motors, these motors motor generators is one of the reasons are far more generally employed in the for the limited use of capacitors in the Coal Co., Penn Anthracite Mining Co., anthracite region than in any of the anthracite region. Other reasons are and Madeira, Hill & Co. For the most bituminous fields of the United States. the extensive use of synchronous motors part these installations were made dur­ This exhibits advanced practice, but in on mine pumps and the fact that several ing 1932 and 1933. one application—mine-fan drives— of the larger companies generate most One of the early applications of syn­ anthracite mines have fewer installa­ of or all of their own power. chronous motors was to the driving of tions than bituminous. Shaft and bore­ Only seven or eight collieries make large stationary air compressors, and the hole cable installation practices of the use of capacitors, and four of the large anthracite region was among the first anthracite region show a wide diversity companies have yet to make their first few that installed this type of equip­ —certain companies use leadless cables installations.