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By C. A. Allen

In presenting a summary of the uses of fine and pulverized coal the writer has borne in mind that we are not trying to determine what a combustion engineer should know but we are only trying to find out in what ways the consumption of slack can be stimulated. First discussing the use of powdered coal it can be stated that it has passed the first experimental stage but is still capable of much development and improvement. It has already found successful application in stationary and locomotive boilers, cement kilns, calcining furnaces, reverberatory smelting furnaces and many other types of furnaces, such as open hearth furnaces and annealing furnaces. For stationary boilers it seems to have been thoroughly demonstrated that powdered coal is more efficient than stoker installations. Over-all efficiences of boiler and furnace in stoker installations of the best type run from 70 to 76 per cent; whereas the efficiency of powdered coal installations averages slightly over 80 per cent. However, due to the increased cost of pulverized coal, the increased efficiency of these installations over stokers, from a money stand-point, will not be more than 1 or 2 per cent. The fusing of the ash in pulverized coal installations has given some trouble but apparently is easily overcome, on the other hand the fine ash, which is carried along with the draft, causes trouble both in the boiler and by settling on surrounding buildings or ground. Offsetting the disadvantages the great advantages of pulverized coal for stationary boilers seem to be: First-the ease with which a change in the load on the boiler can be taken care of. Second-when a boiler is cut out for a short period the "stand-by" losses are much less and, Third-a much poorer grade of fuel can be used. In many cases where pulverized coal has been used it has replaced slack coal which is of little advantage to the coal operator. However,, in other places it has replaced gas or oil and this is where the coal man is interested. Pulverized coal has the same advantages as the liquid or gas fuel but the question as to which is preferable depends on their relative cost at the point of use. In small stationary boilers where stokers are not used, very frequently the larger sizes of coal are, and it would be an advantage to the coal industry for them to be converted so as to burn pulverized coal, but so far there are only records of a few of such small installations having been a success and there is apparently room for a large amount of experimentation. In furnaces, such as smelting and assaying furnaces, annealing furnaces, etc., slack coal is not used and where pulverized coal has been installed it nearly always replaces fuel oil or gas. Just how much increased consumtion of coal can be made by pulverizing it for use in furnaces of this type can not be determined but it seems worthy of investigation. For locomotive boilers pulverized coal has found some application up to date but where it was being used in the United States it was stopped when we entered the war. In Brazil, however, the Central Railway has been using pulverized coal for locomotives with excellent results. If it could be possible to apply it to locomotive use where fuel oil is now used, or the larger sizes of coal, it would certainly make a big difference in the slack situation. Now as to the uses of slack coal without pulverizing. The writer's investigations lead him to believe that the greatest opportunities in this direction are in the line of increasing its use by apartment houses and small home owners. In fact in looking into the subject I found that a number of men in Salt Lake City are using run of mine coal in the usual type of house furnaces, some of them by separating the fines and wetting them down before feeding to the furnace claim they get no loss whatever through the grate. However, for best results with fine coal different types of furnaces must be installed and for apartment houses it would seem necessary to have either a small automatic stoker or else spray the fine coal in with an air blast from

Jan 1, 1922

By C. P. Crawford

Bureau of Mines Technical Paper 172, by S. H. Katz and H. C. Porter, entitled "Effects of Moisture on the Spontaneous Heating of Stored Coal", says at the outset, "Spontaneous fires in storage piles of bituminous coal' have been the source of trouble and loss since the industrial utilization of coal began. In Europe the idea arose that spontaneous combustion is more liable to happen during wet weather than during dry. Statements favoring or opposing this idea have crept into the literature. Conflicting conclusions, based on experiment as well as opinions based on observations of various degrees of reliability, are given in most of the recorded discussions of the subject. "Because of the uncertainty of the effect of moisture and its seeming importance among the conditions that affect spontaneous combustion in stored coal, the work described in this paper was undertaken by the Bureau of Mines. The experiments showed that a coal from Illinois oxidized faster when dry, whereas a sample of Pittsburgh coal oxidized faster when moist. These discordant results and similarly inconsistent results from the observations of different investigators may be coupled with the fact that under actual conditions of, storing, both coal and air always contain a considerable amount of moisture." The foregoing report of the investigations of the Bureau demonstrates that the mystery of spontaneous combustion has not yet been solved. This fact adds to the fascination of the subject. I became interested in the matter about ten years ago in observing what was probably one of the best exhibitions of this phenomenon. The old dump at Castle Gate No. 1 Mine contained boney coal and track cleanings generally. In winter when snow fell upon this old dump, the snow was soon melted by the heat of the dump which was comparatively warm at all times. Within 48 hours afterward little blue flames were in evidence on the surface of the pile. Few of the gas feeders were sufficiently constant to maintain a steady flame at any given point, but shifting emissions of gas were ignited one by another, resulting in a continuous popping and apparent running about of the flames. Another interesting exhibition of spontaneous heating was to be seen a few years ago in the storage coal piles of the local sugar factories. This coal was piled in concrete lined pits and the latter were filled with water. However, or this occasion the coal extended above the surface of the water. At every plant where this condition existed the coal was affected heating, and in each case the affected area was in a plane horizontal to and from 8 to 1.4 inches above the water level. The height of the hot area above the surface of the water appeared to be affected by the fineness of the coal. It is well known that oily rags have a tendency to heat when allowed to accumulate in some location protected from free air circulation. For some reason, as yet unknown, this does not apply to petroleum or its derivatives. Now, the most common explanation of spontaneous combustion is that the combustible material oxidizes by being brought into contact with air in the presence of moisture, the theory being that the moisture acts as a catalytic agent. My theory is that spontaneous combustion is due to oxidation of combustible matter by free oxygen carried in solution by a liquid, the oxidation taking place only as, when, and at the place where this oxygen is released from solution by the evaporation of the liquid. Also, this oxidation takes place to some degree regardless of the condition of the combustible-whether it be lump coal, coal dust, straw, wheat flour, coke, or any other combustible but, as the speed of oxidation is directly influenced by temperature, it follows that spontaneous combustion only becomes noticeable or serious in cases where the resulting heat' cannot escape as fast as it is generated.

Jan 1, 1925

Jan 1, 1926

By D. C. McClure

MR. McCLURE: Mr. Chairman, you sprang a surprise on me; I really came over here for a good time. Gentlemen, I am not at all qualified to pose as an expert on pulverized fuel; I have merely been making some rather interesting observations, and unfortunately at the present time, a great deal of substantial data, the technical data, I don't happen to have with me; it is still in the process of being calculated, but I will be very glad to tell you some of the observations as I have made them, and in as truthful and complete a way as I can. The question of how we would handle fuel became a very pressing subject in this new Valmont electric plant, which is now under progress. We have studied the methods of burning fuel for a number of years on different types of stokers at the existing plants in Denver; we are burning it with a natural draft chain grate and with underfeed and with forced draft chain grates, and I am very frank to confess at the present time that I have no answer as far as stokers are concerned for a better solution of the problem of burning lignite. In other words, I could not tell you that this or that is a better type of stoker to use for that coal. However, to boil the thing down, after considerable trials, the underfed stoker was chosen as the one most adaptable for the utilizing of lignite fuel if stokers are to be used. In other words, the chain grate was put aside. I might say in support of the chain grate, the prime reason for which that type of stoker was condemned, as far as lignite goes, is the initial investment charge and the large maintenance which is involved.

Jan 1, 1923

Our presiding officer for this session is someone we are all proud to be associated with. One who is dedicated to Public Service and Safety in the State of Colorado, and known in the mining field and the Colorado Mining Association. We are very pleased to introduce Mr. Donald Haske, Chief Mine Inspector for the State of Colorado: Donald Haske: Officers, Members and guests. It is certainly my pleasure to be here today and an extra special pleasure to be presiding over this session. As some of you know, from natural up, heavy equipment is rapidly coming to the field of mining. This may seem a long way off at the present, but it certainly isn't. We are getting all the old annuals (Bi) together to be compiled for a guide and public attraction. However, we are unable to locate an (1894 panel). If any of you know of any of these please let us know.

Jan 1, 1967

Jan 1, 1994

PRESIDENT MOSES: I think this will conclude our program for this afternoon, unless you have some- thing else. Mr. Holman, will you tell us what you are doing in the way of your local chapter, around Dawson? W. C. HOLMAN: (Chief Engineer, Phelps-Dodge Corporation, Dawson, New Mexico.) We have organized a local chapter of the Rocky Mountain Coal Mining Institute, and we invite all foremen, fire bosses, shot firers or anybody interested, either on the surface or in the mine. I think at the last meeting we had sixty to seventy men present. We hold meetings once a month; usually on a certain set Tuesday or second Friday of the month, or so on. We have a President, a Vice-President and a Secretary-Treasurer. There are no dues connected with it. We aim to take up the' papers that are presented at the various meetings of the Rocky Mountain Coal Mining Institute, and also any other subject that would be of interest, connected with our own mining operation. We usually ask two or three men to pre- sent papers, rather than one man. We find it difficult in getting one man to work up any subject, but two or three men work up very interesting papers. While we have just recently organized, we aim to have luncheons in connection with it, and possibly once a year a banquet or .some similar activity that we think would interest the men. We feel it is going to be a great help in carrying on the work of the present organization in presenting the activities around the mines. PRESIDENT MOSES: I thank you, Mr. Holman. Has any one any- thing to bring up at this time? MR. LITTLEJOHN: I would like to ask Mr. Holman if the Institute or the Chapter there is confined to Dawson alone, or open to other camps in New Mexico? MR. HOLMAN: At the present, Mr. Littlejohn, it is just confined to our own camp, although we intend to invite the members and the officials of the other camps later on, perhaps. Especially, if we gave a banquet, no doubt we would invite the others. MR. LITTLEJOHN: Is there any other Chapter in New Mexico besides yours in Dawson, Mr. Holman? MR. HOLMAN: None that I know of, right now.

Jan 1, 1926

MR. MARGOLF: Thank you very, very much Harris. There's sure a lot there to think about in terms, of our image, particularly. I think we should keep' in mind what Harris said about our history not being monolithic. Therefore our image can only be that, which is reflecting the weakest link in our industry and I think that's a burden on all of us. Perhaps to do some policing amongst ourselves to try to improve whatever might be our weakest link and thereby elevate our entire industry. Our third speaker this afternoon is another good friend of mine of long standing and I am very pleased to be able to introduce to the Rocky Mountain Coal Mining Institute Bob Golten. Bob is a graduate of the University of Michigan with a degree in Economics and Harvard Law School. His professional experience encompasses private practice in Chicago where he was born and in the federal government as a public defender in Washington, D.C. and in the Department of Justice as a tax , attorney. Some of us have come to know Bob more in his present role as the senior counsel for the I National Wildlife Federation. He's also Adjoint Professor of Law and Director of the National Wildlife Federation Resource Clinic, University of Colorado. Boulder campus. In addition, Bob has served with the Rocky Mountain Center on Environment as one of its directors for a number of years. He's very active in a number of areas that are not only civic but he does reflect what I would present by way of introduction as a perspective

Jan 1, 1982

By S. R. DeBoer

A study of Western cities reveals the fact that a city where people make their homes for permanent residence is always a city with, well-shaded avenues, with parks and playgrounds; in other words, a beautiful city. On the other hand, the average city that lacks these qualifications is usually a city of transient population. Many of our Western cities must be classified as such. Their inhabitants live in such a city only to the time that they will be able financially to retire from business and go to one of the other types of cities to live; or until opportunity offers itself for a position or a job in such a city. I believe that our Western coal camps could benefit by this truth. If conditions can be created in the camps that will encourage the workers to settle permanently or for a long time at least in the town, it would greatly aid in stabilizing employment. By the term "workers" I do not mean the pick and shovel men alone, but everybody from the superintendent or the manager down; for the educated part of the population suffers probably greater from a desire for better surroundings than the less educated part. Modern City Planning tries to show the way for more attractive towns; for more practical towns also, and at less expense. The grid-iron system of street planning is slowly being replaced by one that fits the contours of the site. Instead of streets that are cut through the hills and built over the valleys to get practical grades, it tries to show how these streets can be made to fit the ground and produce better traffic lines; greatly more attractive streets; better building sites and lots, and all of this at less expense. A well-planned town of this character should have as its nucleus, a central square around which the main stores and business houses are grouped. The main building of this group should be the church, the community meeting place, city hall or such other buildings of a public or semi-public character, that are imposing enough to add interest to the square. From this central square, streets should be built to radiate out in all directions, more or less like a spider-web. The main lines of these streets should be reserved for traffic purposes and they should be wide, for the town may grow into a city, and they should be direct, connecting the town center with outlying points at the shortest and easiest possible line. Between these radiating streets should be residential streets of narrower width and arranged in such a way that fast through traffic cannot pass over them and make them unsafe and unsanitary for family life. Following up the comparison with the spider-web, the town should have circular streets, encircling the whole town with rings at various distances out, along which circular lines parks should be located. In the West, where the need for shade is so great, the town should surround itself with a belt of forest trees. Such a forest belt would break the winds and shelter the town, and also make the whole town a cozier, nicer place to build a home in. A forest belt of this kind does not necessarily mean a great layout of money. Trees can be planted small and at little cost and a carefully studied irrigation system will make the maintenance cost small. If the town has any places of natural beauty they should be carefully preserved and made accessible. Natural parks of this type will often take the place of the artificial parks of large cities, and at no expense to the community. Playgrounds, a swimming pool, either of concrete or a sanded beach on a lake; a place for all to go skating in winter; a hill for sledding in

Jan 1, 1924

Jan 1, 1924

BENEDICT SHUBART: I am rather surprised at one statement of Mr. McKeehan, that he found it satisfactory to bond only one track. It has always been my idea of good practice to bond both tracks and cross bond frequently, so that in case of any break in the bonding of one track, which frequently occurs, there will be no interruption in the circuit.

Jan 1, 1923

By P. F. Patterson

It is a well established fact that 60 per cent of all accidents in coal mines occur from falls of roof and coal at or in the proximity of the working face. Notwithstanding that this is well known, and has been frequently discussed by mining men, this seems to be the irreducible minimum. It is even said by those in a position to know that the percentage stated is increasing. With this, information before us it would seem that not enough attention is being given to close supervision at the working face, and until this is done we may expect to continue experiencing an increase in the accidents in this area. No workman generally feels that it is more important to finish loading a car of coal than to set a timber for protection, and many accidents happen from this source, not from a lack of knowledge of the dangerous conditions existing, but negligence in taking remedies necessary to remove the danger. It is true that nearly all state laws require the mine foreman or his assistant to visit each working face every day, but with the constantly changing conditions on account of the advance of the working faces, these daily visits may be entirely inadequate to discover possible dangers and prevent accidents. The obvious remedy then is closer and more systematic inspection and supervision of the working faces. Many accidents are caused in mines on account of not enough clearance between the rib and track or between timber and track. On all main haulage ways. there should be a space of at least 30 inches between the rib and track, or timber and track, and on all rooms not less than two feet should be left between the track and upright timbers.. A great deal has been said and written with regard to systematic timbering. We doubt very much the feasibility of adopting any standard of timbering that would be suitable for all roof conditions, and any such system in our opinion would not tend to cause a decrease in the number of accidents. The proper place to put up a prop, regardless of whether it conforms to any established system, is under a piece of loose roof. No habit is becoming more prevalent among miners and other mine workers than wearing gloves, principally flimsy canvas gloves, which afford no protection to the wearers and are the direct cause of many hand injuries. If gloves must be worn, and no doubt they will be as the habit has become well established, then they should be made from some heavy material and should fit the hands fairly snug.

Jan 1, 1923

RMCMl PRESIDENT CHARLES W. MARGOLF on behalf of The RMCMI Board of Directors and Officers invites you and your family to attend The 81st Regular Meeting and Convention of The Rocky Mountain Coal Mining Institute to be held at Tamarron, Durango, Colorado JUNE 30, JULY 1 AND 2, 1985

Jan 1, 1984

PRESIDENT PRYDE: Any discussion on Mr. Poster's paper? MR. J. BEVAN: I would like to ask the gentleman how fine the dust has to be to cause an explosion? MR. T. FOSTER: According to the Bureau of Mines, it is claimed coal passing through a 100 mesh screen would be considered fine enough. That is all I can learn from the different bulletins. MR. BEVAN: Will the coal dust be that fine; going back in the empty cars on the tipple in the mine? MR. FOSTER: Possibly a great deal of it would be. MR. BEVAN: Will the coal dust be that fine, going back, in the empty the coal dust going back in the cars on the tipple, and into the mine? MR. FOSTER: In some places, they are wetting the cars at the tipple, -in the Rock Springs District, we have as the trip goes out, they have a big pipe, and they souse the car, and wet the load, and in some places, near the timbers; that helps to a certain extent. That does not absolutely eliminate it all, but it helps considerable. MR. WM. LITTLEJOHN (Utah Fuel Company) : I think we have all listened very attentively to the paper that Mr. Foster has just read. He has brought up a subject rather close to my heart, for a long time. He mentions particularly, the Scofield disaster, which happened the first of May, 1900; two hundred men lost their lives in the explosion; and I think it is generally conceded that is about the first time it had ever been brought to the attention of coal miners or operators that such a thing was possible, namely, a purely coal dust explosion. The term "Scofield disaster" is rather a mistake, in a way; while the mine that exploded at the time is in the Scofield District all right, it is now known, and probably was known at that time, as the Winter Quarters Mine, one of the mines which belongs to the Utah Fuel Company at the present time, and did at that time. This mine

Jan 1, 1924

Jan 1, 1926

Briefly, the machine consists of a steel frame mounted on roller bearing wheels and axles, an electric motor, a fully enclosed speed reduction gear unit, a specially designed centrifugal pump driven through a friction clutch and silent chain, a mixture tank and agitators, and all necessary operating and control mechanism. The wheels are mounted on solid roller bearings made of special roller bearing steel, and are cast with deep chilled threads. The axles are of high carbon axle steel. A General Electric Company motor, of special design to exclude dirt and moisture, is used. It has an unusual overload capacity and a maximum torque at starting speed. Special arrangement can be also made for storage battery operation. The motor drives from one end, through a flexible coupling, to the speed reduction unit, and from the opposite end, through a similar coupling, to the pump clutch. The design of the flexible couplings is such that the drive is reversible. The speed reduction gears are enclosed in an oil and dust proof housing. All spur gears, as well as the main drive clutch, are made of steel forgings, with accurately cut teeth. An aluminum bronze worm wheel and special heat treated alloy steel worm provide the speed reduction for the traction drive. The worm shaft is mounted on Hyatt roller bearings and the thrust is taken in each direction by ball thrust bearings. The main drive shafts are of special alloy steel and operate in Hyatt roller bearings. The slow speed shafts run in extra large bronze bushings. Ample and constant lubrication is provided by splash from the gears running in oil. The Mudite pump is of special de- sign. A renewable wearing plate protects the pump casing from the natural wear of the mixture. The open runner is mounted on an extra large shaft which runs in a Hyatt roller bearing on the pump end and in Timken roller bearings on the outboard end. A special cage prevents water and grit from reaching the pump bearing. All thrust from the runner is taken on the Tim- ken bearings and these bearings also provide for the accurate and easy adjustment of the runner. The pump is driven by a silent chain, which operates on cut steel sprockets, from a friction clutch. The clutch is designed to secure long wearing qualities with minimum attention and its adjustment is easily effected. It is mounted on Hyatt roller bearings and the clutch drive shaft also runs in the same type of bearings. The pump discharges through a nozzle, which is adjustable, and controlled by the operator. The mixture tank is of approximately 650 gallons capacity. It is provided with a mixing well constructed of perforated plate screen to prevent large hard particles from getting into the valve or pump. The tank is filled through an opening in the top directly into the mixing well. On a shaft running longitudinally through the tank are arms so arranged that the mixture is thoroughly mixed and kept in continuous circulation from end to end. This shaft is driven from the speed reduction unit by a steel roller chain operating on cut sprockets. The traction drive is taken from the worm wheel shaft through steel roller chains of extra large size that run on cut steel split sprockets on both axles. An idler sprocket provides for easy chain adjustment. The axles are mounted in solid roller bearings in fully-enclosed dust proof housings, which support the frame through coil springs. These springs eliminate twisting strains on the frame on account of track irregularities and also relieve the working mechanism from road shocks. The speed reduction from the motor to the wheels is such that it gives an operating speed of approximately ninety to one hundred thirty feet per minute. The brakes are of the conventional shoe type and engage the wheels on both axles. They are operated by a hand wheel conveniently located and

Jan 1, 1925

President John T. Atkins on behalf of The RMCMl officers and Executive Board, invites you and your family to attend The 80th Regular Meeting and Convention of 'The Rocky Mountain Coal Mining Institute to be held at Marriott's Mark Resort, Lionshead Village in Vail, Colorado JUNE 24 - JUNE 26, 1984

Jan 1, 1983

WILLIAM P BALAZ RMCMI PRESIDENT 1990-1991 on behalf of the RMCMI Board of Directors and Officers of The Rocky Mountain Coal Mining Institute cordially invites you and your family to attend the 87th Regular Meeting and Convention to be held June 30, July 1 & 2, 1991 Keystone Resort, Colorado

Jan 1, 1990

PRESIDENT LITTLEJOHN: I have every reason to know Mr. Pryde was carrying out some experiment a while ago in some of his mines. He and I had a little correspondence on the question, and I think he may have a word or two to say about it. He has not been on his feet today at all. I will ask Mr. Pryde to tell us what he has to say. MR. PRYDE: I have not very much to say about shooting coal with permissible powder as far as slack is concerned because we are not in the commercial business. All of our coal goes to the railroad and a very large part of it is crushed for use in the stokers of the locomotives. We are on a 100 per cent permissible powder basis and as far as I am able to see, I do not believe that the percentage of slack is increasing with its use. We find it hard to convince our commercial neighbors of this fact because they are naturally very much against increasing their percentage of slack on ac- count of the low price received for this grade of coal. I, personally, believe that where a change is made from black powder to permissible powder the percentage of slack will be increased for a time because the miners have been accustomed to using black powder and they are rather suspicious about going to the permissible powder and I do not believe that we can blame them very much. So the tendency with them is to use too much powder. We have gradually overcome this, although, as I said before, we have not kept close track of the production of slack. However, we try to get as large an amount of lump coal as possible. Broadly speaking, I can say from observation that in my opinion there is very little difference in the percentage of slack with the use of the permissible powder that we have today than there was with the use of black powder. I also get this information from our mine superintendents. Mr. Peterson and the other explosive men have been very helpful to us in the use of permissible powder and I confess I have to take everything back that I said several years ago. At that time I was against permissible powder, particularly on account of the cost, but, with the newer permissible powder, we have gotten the cost down very well. I know today that the cost of permissible powder in the coal mines of the Union Pacific Coal Company is less than when we were using black powder. I know this because of the fact that we kept a record of the number of tons we got with black powder, and the number of tons we get with permissible powder compares very favorably in cost. I know this, too, because of the fact that our employes, except in the first few weeks of using permissible powder, have made no demand upon us for any in- crease ill pay to offset any added cost that might accrue in the use of permissible powder and the fact that they have asked for no increase is very conclusive proof to me that it is not

Jan 1, 1925

MR. GIBSON (continuing): In connection with the coal from this mine, I will say that it is not a very dirty coal. The vein where most of the coal comes from is about eight feet thick, and two feet from the bottom there is a small boney band about two inches thick. The breaking shot has to be placed over the, band, therefore breaking the boney into fine particles which goes off with the slack. This coal is a very good domestic coal and the slack is in great demand for various power, plants, such as sugar plants, smelters and other industries, but where this, boney is broken up and goes into the slack, it is very injurious in effect and retards the sale of the slack. Therefore the Spring Canyon Coal Company went to the expense of' building this plant, costing over $250,000, just in order to get that, two inches of boney coal out of the rest of the vein. The market in, Utah is very critical, and in order to sell coal, the product must be thoroughly clean in every way and, as Mr. Murphy says, I believe they have succeeded in making a very good commercial product. In any event the Spring Canyon Coal Company put out more coal than any other one mine during the last year, 1924, they had the largest production. I thank, you. (Applause). PRESIDENT MARKS: With the assistance of Mr. Robinson and Mr. Miller, I am sorry you could not get the pictures a little better synchronized with the story. MR. F. C. MILLER (Chief Chemist The Colorado Fuel & Iron Company, Pueblo) : We had seven slides to show eighteen different views on the screen and we did remarkably well. (Laughter.) PRESIDENT MARKS: Is there : any further discussion on this paper? MR. G. B. JONES (Mining Inspector, Victor-American Fuel Co.) : I would like to ask a question on the

Jan 1, 1926