831 
 T35- 
 
 '^'y 
 
 •J. %«*^(^' 
 
 y'- ^ 
 
 k^ 
 
 '~^V, 
 
 5i£ji.: 
 
 X. 
 
 ;f¥« 
 
 .M 
 
 S-Su^.,,.,/- 
 
 ■ /-.<* 
 
 j^^-^il^^mti 
 
 C- 
 

 THE GIFT OF 
 
 batg 
 
 
 J\v..V..0.1.|.^^ 
 
 
 
 
 ul'Min 
 
 tWGINEERING LIBRARY 
 
 ' 
 
Cornell University 
 Library 
 
 The original of tiiis book is in 
 tine Cornell University Library. 
 
 There are no known copyright restrictions in 
 the United States on the use of the text. 
 
 http://www.archive.org/details/cu31924004675249 
 
PRELIMINARY REPORT 
 
 ON THE 
 
 UTILIZATION OF LIGNITES. 
 
 E. T. DUMBIvE, Statb Geoi,ogist. 
 
 Hon. John E. HolUngsworth, Commissioner of Agriculture, Insurance, Statistics 
 and History: 
 
 Sir — In accordance with your instructions, under an act of the I,eg-' 
 islature directing an investigation into the methods of using lignite in 
 Europe, I visited the principal deposits of browncoals in Germany and 
 Austria, compared the different varieties with those of Texas, and ex- 
 amined the various methods of utilizing them. 
 
 While the limited time which I could give to this investigation pre- 
 vented my visiting the deposits of France and Italy, the results are so 
 satisfactory, full and conclusive, that an inspection of these localities 
 was not absolutely necessary, although it would doubtless have been 
 instructive in many ways. 
 
 Throughout my entire trip I met with the kindest attention and with 
 the most ready and valuable assistance from the geologists and mining 
 officers, both public and private; and it was only through the opportu- 
 nities thus afforded that I was enabled, in the time at my disposal, to 
 cover so much ground and gather the necessary information. In the fol- 
 lowing report, which must be regarded as merely preliminary,! have sum- 
 marized the results of my investigations. As soon as I can prepare it, 
 a full report will be made which will contain many details, references 
 and descriptions which cannot be included here. 
 
 EUROPEAN BROWNCOAI,. 
 
 The browncoal of Europe may be divided into four general classes, 
 viz.: 1, Lignite; 2, Common Browncoal; 3, Pech Coal; 4, Glance 
 Coal — all of which have representatives in Texas. 
 
 , LIGNITE. 
 
 In Germany and Austria this term is only used to designate such 
 fossil fuel as fully retains its woody character and fiber. It is usually 
 found accompanying other varieties of browncoal, and consists of those 
 fragments of the original woody material from which the beds were 
 formed that have escaped maceration and decomposition. In some 
 places, however, when conditions were favorable to its preservation it 
 forms the main body of the deposit. Sometimes it occurs surrounded 
 by earthy browncoal, and often has particles of fatty browncoal or jet 
 inclosed with it, following the rings of growth. Much of it as it comes 
 
z UTILIZATION OF LIGNITES. 
 
 from the mine retains its form and character so completely as to be 
 almost indistinguishable from the ordinary wood of the present time, 
 except that it is somewhat darker in Color. 
 
 COMMON BROWNCOAL. 
 
 This name covers a number of varieties, varying in color from yellow 
 to brownish black, "and from those having a specific gravity less than 
 water to those of 1.2 and 1.3. Their common qualities are their large 
 percentage of water and their earthy, friable nature. The two most 
 important of these varieties are "Schweelkohl" and Earthy Brown- 
 coal. 
 
 ScHWEEL Coal. — This variety, in its purest form, resembles a yel- 
 low clay much more closely than it does coal. Its composition and 
 character, as revealed by chemical analysis and the microscope, vary 
 somewhat from the other browneoals, and it is the variety which has 
 the least specific gravity. It is the richest in tarry matter, and is 
 therefore especially desirable for the manufacture of parafiine and oils. 
 It occurs most frequently with earthy browncoal and often in alternat- 
 ing layers with that variety. 
 
 Earthy Browncoal. — This variety of browncoal is, as its name 
 indicates, of an earthy character, brown to brownish black in color, in 
 its ordinary condition containing as much as forty-five or even fifty 
 per cent of moisture. While it somewhat resembles our Texas brown- 
 coal, especially in the fatty streaks which occur in it, the German is 
 much more friable than ours and also much inferior to it in heat- 
 ing value in the raw state on account of the great percentage of water 
 it contains. This is the character of browncoal that is found most 
 largely developed in the district around Halle, a. S., and in the Rhine 
 provinces. Much of it lies very near the surface, in beds varying from 
 a few inches to sixty feet in thickness, and is most often mixed with 
 Schweel coal to a greater or less extent. From this variety of brown- 
 coal is manufactured the ' ' nass-press-stein ' ' and browncoal briquettes 
 without bond. 
 
 PECH coal. 
 
 A darker and firmer variety of browncoal, which contains a smaller 
 amount of water, and which often closely resembles pitch both in color 
 and fracture, is called Pech coal. The coal of the Bohemian basins is 
 very largely a mixture of common browncoal (of somewhat drier na- 
 ture than the German) and Pech coal, together with some lignite, and 
 is the equivalent of the larger part of our Texas deposits. 
 
 GLANCE coal. 
 
 This is the finest variety of lignitic or browncoal, in certain instan- 
 ces passing into jet. It occurs principally in Styria with other varie- 
 ties of browncoal, although smaller quantities occur in many locali- 
 ties. 
 
 These varieties are again subdivided into minor divisions, and they 
 pass by insensible gradations one into the other, frequently in one and 
 the same bed. » 
 
 STATISTICS. 
 
 The following statistics, taken from the government reports of the 
 
UTILIZATION OF LIGNITES. O 
 
 empires of Germany and Austria, show to what extent these brown- 
 coals were used during the year 1890: 
 
 Tons mined. Value at mine. 
 
 Germany. ~ 1.5,468,434 $9,967, 812 00 
 
 Austria.. 1.5,329,056 12,482,603 00 
 
 Total.. , 30,697,490 $22,450,415 00 
 
 Of which — 
 
 Rhine Provinces 661, .590 $381,139 00 
 
 Halle, a. S 14,077,382 9,031,238 00 
 
 Styria 2,270,023 2,942,327 00 
 
 Bohemia 12,190,932 8,240,780 00 
 
 This amount, over three hundred thousand car loads, is nearly thirty 
 per cent of the entire coal fstone coal and browncoal) production of 
 these empires, which was (for 1890) 104,702,370 tons. Of the total 
 amount of browncoal mined, the district around Halle, Germany, and 
 Bohemia and Styria, in Austria, produced eighty per cent. 
 
 The amount of browncoal used in the manufacture of briquettes, 
 coal bricks, tar, paraffine, etc., during the year was a little less than 
 seven million tons, and the remainder — over twenty-three million tons 
 — was used "raw," or just as it came from the mine, without prepara- 
 tion of any kind. 
 
 USES OF EUROPEAN BROWNCOAL. 
 
 As has already been stated in our circular No. 8 and in the various 
 reports of this Survey, the uses of browncoal are as varied, general and 
 important as those of stone coal. The results of my personal investi- 
 gations not only fully confirm the statements made heretofore by my- 
 self and other members of the Survey, in regard to the availability of 
 the Texas browncoal for fuel purpos'es, but add greatly to them. 
 
 LIGNITE. 
 
 When lignite is found in sufficient quantity, it is chari-ed in meilers, 
 kilns or retorts, in the same manner as ordinary wood, and yields a 
 charcoal of similar quality and equally suitable for all fuel purposes. 
 Thus, in lower Styria, where it occurs in great quantities as a part of 
 a browncoal deposit, having a total thickness of over three hundred 
 feet, it is charred in ovens arranged for the recovery of the by-products 
 as well as the charcoal. The charcoal made here is used in iron smelt- 
 ing. 
 
 Where the lignite occurs in smaller quantities, as in the province of 
 Saxony and on the Rhine, it is used with the browncoals under steam 
 boilers and for various other fuel purposes. 
 
 COMMON BROWNCOAL. 
 
 The Schweelcoal, as has already been stated, contains large amounts 
 of tarry matter, and for this reason is especially desired by the Schweel- 
 eries or factories which manufacture from it the tar and its derivatives, 
 paraffine and oils of various grades. These oils vary in quality from 
 one especially adapted for the manufacture of gas for lighting pur- 
 poses, through heavy and light oils to a solar oil about equivalent to 
 
4 UTILIZATION OF LIGNITES. 
 
 our best refined petroleum. While the introduction of American and 
 Russian petroleum into Germany has in some measure checked the 
 working of the Schweeleries for oil purposes, the demand for paraffine 
 is so great as to keep the factories still at full work. This industry, 
 as shown by the statistics given, is one of great importance to these 
 districts of Germany, amounting as it does to over four millions of. 
 dollars annually and giving employment to several thousand men. 
 The records of the German Browncoal Association show that in the 
 year 1890 the amount of browncoal used by the companies belonging 
 to the association for the manufacture of tar and paraffine was over 
 twenty millions hectolitres, and the value of the product seventeen 
 million one hundred and twenty thousand marks ($4,280,000.) The 
 coke made from the Schweelcoal by this process is called ' 'grude coke, ' ' 
 and experience has proved it to be such an excellent fuel for house- 
 hold purposes that the demand is in excess of the supply. It is used 
 in stoves of special construction for cooking and heating. It is of too 
 fine a grain and not compact enough to.be of any use in smelting iron. 
 
 The earthy browncoal is used "raw," or as it is mined, for house- 
 hold, manufacturing, or steam purposes, and is also manufactured 
 into nass-press-stein and briquettes. 
 
 Nass-press-stein, or coal bricks, are made .by mixing the browncoal 
 with water until it is of a putty like consistency, compressing by rna- 
 chinery similar to that used in making pressed brick, and then drying 
 these brick in the air. While the amount of this fuel is small in com- 
 parison with that of briquettes made by the dry method, it is never- 
 theless a useful and serviceable fuel for household purposes. 
 
 Dry briquettes, made from this variety of browncoal, are in_ great 
 demand, and the output is increasing yearly. The process of manu- 
 facture consists of drying the browncoal by one of the several methods 
 until the water contained in it is reduced to a certain percentage and 
 then compressing it under a pressure equal to that of fifteen hundred 
 to two thousand atmospheres. The resulting briquette is of a lozenge 
 or elliptical shape, some six inches in length and about one inch in 
 thickness, very firm and durable. The compression is so perfect that 
 the. briquette will not absorb water even if it be laid in it for some 
 time. The earthy browncoal is preferred for briquette making on ac- 
 count of the ease with which it is pulverized. 
 
 In a raw state browncoal is also used for burning bricks, stoneware', 
 and drain tile, for which purposes it is preferred to any other fuel. 
 Brick clays and fire clays are often found in close proximity to the 
 browncoal, and the manufacture of bricks, fire brick and tiles, at an 
 extremely low price, is thus rendered practicable, and a great number 
 of mines have brick yards in connection with them by means of which 
 they are enabled to make use of all their coal, even what would other- 
 wise be refuse. 
 
 At one of the larger brick works on the Rhine the experience of 
 several years trial proved that a firing with a mixture of browncoal 
 briquettes^ and raw browncoal gave better results in actual work than 
 stone coal alone, stone coal with briquettes, or stone coal and raw 
 browncoal, and at the time of my visit works were just being com- 
 pleted for briquetting their browncoal for use in this manner. 
 
 In using this earthy browncoal for such firing purposes, or under 
 steam boilers and elsewhere, due attention is given to the arrangement 
 of the fire-boxes and grates to suit the fuel. If a flat grate is used the 
 
UTILIZATION OP LIGNITES. O 
 
 grate bars are made very narrow and with small intervals between 
 each. The favorite grate, however, is called the ' ' treppen rost, ' ' and 
 is a grate arranged in a series of steps by which the air gets proper 
 access to the browncoal without need of a blast suiEcient to carry 
 away the smaller particles unburned. 
 
 For household purposes stoves of suitable construction for cooking 
 and heating, using raw browncoal or briquettes as fuel, are for sale 
 everywhere in Germany. The briquettes are preferred for fuel on ac- 
 count of their cleanliness and freedom from smoke in burning. 
 
 The comparative extent of the use of the various fuels in the ordi- 
 nary way may be seen from the statistics of the fuel supply of the 
 City of Berlin for the year 1890, taken from the annual report of the 
 Kohlenzeitung: 
 
 Stone coal, coke, etc. 1,755,383 tons. 
 
 Bohemian larowncoal 242,027 tons. 
 
 German browncoal briquettes 577,674 tons.. 
 
 German browncoal 21,534 tons. 
 
 Total browncoal ■.• 841,235 tons. 
 
 or about thirty-one per cent of the entire fuel supply. 
 
 A great many tests have been made to determine the ratio of fuel 
 value of the German browncoal and stone coal. The results give the 
 ratio between the Westphalian coal and earthy browncoal and briquettes 
 about the following relation in amounts required to produce the same 
 amount of steam: 
 
 Westphalian Coal. German Browncoal. Briquettes. 
 
 1. 2 to 2J^ 1% toiy^ 
 
 The Bohemian browncoal contains less moisture than the common 
 browncoal of Germany, and is therefore a better fuel in its raw state. 
 Throughout Bohemia it is put to every use — domestic, manufacturing 
 or metallurgical — for which stone coal is used, except the smelting of 
 iron ores and production of pig iron. The locomotives, which have 
 very heavy work over the mountain railways, use it exclusively. 
 Brick works, chemical works, glass factories, firebrick and tile works, 
 potteries, cement factories and limekilns are all run successfully and 
 economically with this browncoal as their only fuel. It is used as fuel 
 exclusively by the largest iron and steel works of the country for the 
 processes of converting pig iron into wrought iron and steel and for 
 rolling this into rails, bars, wire, sheet iron and all similar products. 
 
 The use of this fuel in this manner was made possible by a close 
 technical study of its character and a practical application of the results 
 to manufacturing purposes. The construction of the fireboxes and 
 grates is such tha:t the necessary conditions to its best utilization are 
 fulfilled, and when high heats are wanted for smelting iron or heating 
 ingots, as in the manufacture of wrought iron and steel and in rolling 
 mill work generally, gas firing is resorted to. 
 
 This kind of firing, which is the one most generally in use with the 
 browncoal for all purposes where the higher temperatures are required, 
 has several different methods of application, varying with the purpose 
 for which the heat is required, but all having the same general principle 
 at the foundation. 
 
 The browncoal is first converted into gas by burning in a producer 
 of some description, usually a rectangular firebox with treppen rost 
 
b UTILIZATION OF LIGNITES. 
 
 grate, fed from above. The gases produced in burning are carried off 
 by proper conduits, the tarry matters separated, in part at least, by 
 passing through an hydraulic main, and the remaining fixed gases pass 
 either directly to the turnace or more often through a Siemens re- 
 generative furnace to the place where they are burned. Here they 
 are mixed with heated air and the heat produced by the combustion is 
 ample for any and all purposes for which it may be required. The 
 Bohemian browncoal has also been successfully briquetted after the 
 German or dry method, already mentioned, and a factory has been in 
 operation for several years at Koenigsberg, near Carlsbad. 
 
 This coal has also been coked by several methods, but up to the 
 present time the coke has not been brought into use as fuel. In 
 some places this was prevented by the character of the coke itself, 
 which was unsuited for blast furnace purposes. In other cases, 
 when the coke was suitable for such use, the cost of producing it was 
 so great that it.could not successfully compete with the cheap Silesian 
 coke from stone coal. 
 
 In Styria there is found a still drier browncoal which in places very 
 closely resembles jet. It is probably the equivalent of our I^aredo coal, 
 except that it contains very much less ash. This browncoal is of ex- 
 cellent quality, and has also been coked by methods similar to those 
 used with the Bohemian, but the coke is not in use at present for the 
 same reasons given above. It has, however, been found not only prac- 
 ticable but economical to use thirty per cent and upward of this raw coal 
 in connection with coke from stone coal in the blast furnace for smelt- 
 ing iron ore and there are iron furnaces which have been in operation 
 for years using this character of fuel. ' 
 
 This browncoal, mixed with a lignitic coal, is used in the same 
 vicinity for rolling mills,- steel and wrought iron production, etc. The 
 browncoal of Bohemia aiid Styria is also used in the manufacture of 
 gas for lighting purposes. It is distilled in retorts of the usual 
 form and the operation differs in nowise from that with ordinary bitu- 
 minous coal, except that the heated air from the furnace is used to 
 evaporate the surplus moisture from the raw browncoal before it is put 
 in the retort. The gas coke made from the browncoal in Bohemia is 
 sold for use in the zinc works. 
 
 In Styria a browncoal similar to that of Texas is briquetted with a 
 bond of stone coal pitch. Only the smalls are used, because there is 
 usually a demand for all the lump coal that can be mined throughout 
 this w^hole region and the briquette industry is therefore not needed. 
 The briquettes are, notwithstanding, sold at a price fully equal to that 
 of stone coal. The system used is the Coufinhal, and the briquettes 
 are like those now in the Museum of the Survey, which were made 
 during my earlier experiments. 
 
 From these facts it will be seen that the browncoals of Germany and . 
 Austria are not only adapted for use as fuel for all purposes, but that 
 they are so used, and used successfully. Moreover, the statistics show 
 conclusively that the browncoal industry of Germany and Austria is 
 one of very great magnitude, and it will be shown by a comparison of 
 statistics for twenty or thirty years past that the increase in the pro- 
 duction of browncoal has kept fully abreast of that of stone coal. 
 
UTILIZATION OF LIGNITES. I 
 
 COMPARISON OF EUROPEAN AND TEXAS LIGNITES. 
 
 As stated in the beginning of this report, I have compared our 
 Texas lignites with those of Germany and x\ustria, and find that we 
 have representatives of the various classes mentioned. I have per- 
 sonally examined the various classes of browncoal as they occur in 
 the deposits, as thej' come from the mine, and as they are used in 
 their various applications, and I have compared them with our Texas 
 lignites, both in their physical character and chemical composition, 
 with the result as stated. I have submitted average specimens of our 
 Texas browncoals to the highest authorities on this subject in Ger- 
 many and Austria, and they, without exception, confirm my state- 
 ment, and unite in pronouncing the Texas browncoals of excellent 
 quality, fully equal to the Bohemian, and equally suitable for use for 
 all domestic, industrial and metallurgical purposes. I have therefore 
 the pleasure of reiterating the statement made several times already, 
 and each time supported by stronger evidence, that Texas has in the 
 immense deposits of browncoal a cheap fuel which can be used for 
 every purpose for which fuel is needed. 
 
 It should, however, be plainly understood in the beginning, that 
 the browncoals of Texas will be found to differ very widely in quality, 
 and it will require analyses of each deposit to tell with certainty for 
 what purpose it is best adapted. Deposits will be found containing 
 too large a percentage of ash, and some perhaps too large a percentage 
 of sulphur, to be of value as fuel, although other uses may be found 
 for them. Those that are suited for briquetting without bond may 
 not serve equally well for other purposes, and some of the varieties of 
 browncoal will not form a briquette at all by the dry method. 
 
 It is impossible, "with detached basins of browncoal, formed under 
 somewhat diverse conditions and stretching across an area seven 
 hundred miles in length, that all should be equally good. That there 
 is an abundance of the material that is of a most excellent quality is 
 .shown by the examinations and analyses already made by the Survey 
 of deposits and specimens from all portions of the lignite belt, and yet 
 other of these analyses also prove the existence of deposits which are 
 comparatively worthless. 
 
 Therefore, in any undertaking having browncoal as its basis of 
 supply, either as fuel or raw material for manufacturing purposes, an 
 accurate knowledge of the material should be obtained before opera- 
 tions are begun. 
 
 UTILIZATION OF TEXAS BROWNCOAL. 
 
 The fact of the great fuel value of the browncoal having been thus 
 fully decided, I have endeavored to secure all possible information, 
 and when practicable the detailed drawings or plans of the various 
 kinds of ovens, fireboxes, grates and appliances for using browncoal. 
 Some of these are the subjects of patents, and can therefore only be 
 used under royalty or purchase; others, and some of these the most 
 important, are not patented and are free to all. 
 
 Through the kindness of the owners of the iron works and rolling 
 mills in Bohemia and Styria, I have secured plans in detail of the fire- 
 boxes, gas producers, and arrangements by means of which they use 
 the raw browncoal for the purposes stated. I have also the plan of the 
 
o UTILIZATION OF LIGNITES. 
 
 blast furnaces which are now in operation using a mixed fuel of coke 
 and raw browncoal. 
 
 From the manufacturers of locomotives I will have detailed plans of 
 the fireboxes used on such locomotives as are intended for browncoal. 
 All of these plans and methods are applicable for the use of our Texas 
 browncoal for similar purposes. 
 
 The machinery for the production^of briquettes by the dry method is 
 manufactured in Germany, the most of it under patents. General 
 descriptions and estimates of the cost of erection are in the oflBce. 
 
 Presses and machinery for the production of briquettes using pitch as 
 a bond are manufactured in Germany, France and England. I have 
 plans and estimates of the different styles and sizes of these showing 
 approximate cost of erection and operation. 
 
 Plants for the prodiiction of tar, paraflBne, oils, etc. , from the brown- 
 coals are of a much more complex nature. General plans and estimates 
 are now in the ofiice, and details will be furnished me as soon as they 
 can be prepared. 
 
 Some of the principal uses of our browncoal will undoubtedly be in 
 the manufacture of brick, firebrick, drain tile, paving tile, stoneware, 
 pottery, glassware, cement and lime. Plans for the construction of 
 ovens especially designed for these purposes and in successful use in 
 Germany with browncoal firing are also being prepared. 
 
 All of these are at the service of those interested in the subject. 
 
 It can be stated now from experiments and analyses already made, 
 both by private individuals and by the Survey, that we know that we 
 have in the Texas browncoals certain varieties that are rich in tarry 
 matter which will serve as a spurce of paraffine, and that some varieties 
 can be briquetted with pitch as a bond and others .by the dry method. 
 
 Special examinations and tests of our Texas browncoal by the largest 
 browncoal manufacturing establishment in Europe, by the various 
 methods of briquette manufacture in Germany and France, and by 
 other specialists are now in progress, and as soon as their final reports 
 are received the results will be published, together with the details of 
 the various plants, estimates of the cost of erection, operation, etc. 
 
 Austin, Texas, November, 18, 1891.